IoT Tips

    Step 4: Write Data to External Database You’ve connected to the database, you’re able to query the database. Now let’s handle inserting new data into the database. The update statements and data shown below are based on the table scripts provided in the download. Examples of how the ThingWorx entity should look can be seen in the SQLServerDatabaseController and OracleDatabaseController entities. Running an Insert Follow the steps below to set up a helper service to perform queries for the database. While other services might generate the query to be used, this helper service will be your shared execution service. In the DatabaseController entity, go to the Services tab.   Create a new service of type SQL (Command) called RunDatabaseCommand. Keep the Output as Integer. Add the following parameter:  Name           Base Type       Required command String True 5. Add the following code to your new service: <<command>> 6. Click Save and Continue. Your service signature should look like the below example. You now have a service that can run commands to the database. Run your service with a simple insert. There are two ways to go from here. You can either query the database using services that call this service, or you can create more SQL Command services that query the database directly. Let’s go over each method next, starting with a service to call the helper. In the Services tab of the DatabaseController entity, create a new service of type JavaScript. Name the service JavaScriptInsert_PersonsTable. Set the Output as InfoTable, but do not set the DataShape for the InfoTable. Add the following code to your new service: try { var command = "INSERT INTO Persons (person_key, person_name_first, person_name_last, person_email, person_company_name, " + "person_company_position, person_addr1_line1, person_addr1_line2, person_addr1_line3, person_addr1_city, person_addr1_state, " + "person_addr1_postal_code, person_addr1_country_code, person_addr1_phone_number, person_addr1_fax_number, person_created_by, " + "person_updated_by, person_created_date, person_updated_date) VALUES ('" + key + "', '" + name_first + "', '" + name_last + "', '" + email + "', '" + company_name + "', '" + company_position + "', '" + addr1_line1 + "', '" + addr1_line2 + "', '" + addr1_line3 + "', '" + addr1_city + "', '" + addr1_state + "', '" + addr1_postal_code + "', '" + addr1_country_code + "', '" + addr1_phone_number + "', '" + addr1_fax_number + "', '" + created_by + "', '" + updated_by + "', '" + created_date + "', '" + updated_date + "')"; logger.debug("DatabaseController.JavaScriptInsert_PersonsTable(): Query - " + command); var result = me.RunDatabaseCommand({command: command}); } catch(error) { logger.error("DatabaseController.JavaScriptInsert_PersonsTable(): Error - " + error.message); } 5. Add the following parameter:  Name                                   Base Type           Required key String True name_first String True name_last String True company_name String True company_position String True addr1_line1 String True addr1_line2 String True addr1_line3 String True addr1_city String True addr1_state String True addr1_postal_code String True addr1_country_code String True addr1_phone_number String True addr1_fax_number String True created_by String True updated_by String True created_date String True updated_date String True 6. Click Save and Continue. Any parameter, especially those that were entered by users, that is being passed into a SQL Statement using the Database Connectors should be fully validated and sanitized before executing the statement! Failure to do so could result in the service becoming an SQL Injection vector. Now, let’s utilize a second method to create a query directly to the database. You can use open and close brackets for parameters for the insert. You can also use <> as a method to mark a value that will need to be replaced. As you build your insert statement, use [[Parameter Name]] for parameters/variables substitution and <<string replacement >> for string substitution. In the Services tab of the DatabaseController entity, create a new service of type SQL (Command).   Name the service SQLInsert_PersonsTable. Add the following code to your new service: INSERT INTO Persons (person_key ,person_name_first ,person_name_last ,person_email ,person_company_name ,person_company_position ,person_addr1_line1 ,person_addr1_line2 ,person_addr1_line3 ,person_addr1_city ,person_addr1_state ,person_addr1_postal_code ,person_addr1_country_code ,person_addr1_phone_number ,person_addr1_fax_number ,person_created_by ,person_updated_by ,person_created_date ,person_updated_date) VALUES ([[key]] ,[[name_first]] ,[[name_last]] ,[[email]] ,[[company_name]] ,[[company_position]] ,[[addr1_line1]] ,[[addr1_line2]] ,[[addr1_line3]] ,[[addr1_city]]]] ,[[addr1_state]] ,[[addr1_postal_code]] ,[[addr1_country_code]] ,[[addr1_phone_number]] ,[[addr1_fax_number]] ,[[created_by]] ,[[updated_by]] ,[[created_date]] ,[[updated_date]]); 4. Add the following parameter:  Name                                  Base Type       Required key String True name_first String True name_last String True company_name String True company_position String True addr1_line1 String True addr1_line2 String True addr1_line3 String True addr1_city String True addr1_state String True addr1_postal_code String True addr1_country_code String True addr1_phone_number String True addr1_fax_number String True created_by String True updated_by String True created_date String True updated_date String True 5. Click Save and Continue. Examples of insert services can be seen in the provided downloads.   Step 5: Executing Stored Procedures There will be times when a singular query will not be enough to get the job done. This is when you'll need to incorporate stored procedures into your database design. ThingWorx is able to use the same SQL Command when executing a stored procedure with no data return and a SQL query when executing a stored procedure with an expected result set. Before executing these services or stored procedures, ensure they exist in your database. They can be found in the example file provided. Execute Stored Procedure Now, let's create the service to handle calling/executing a stored procedure. If you are expecting data from this stored procedure, use EXEC to execute the stored procedure. If you only need to execute the stored procedure and do not expect a result set, then using the EXECUTE statement is good enough. You're also able to use the string substitution similar to what we've shown you in the earlier steps. In the DatabaseController entity, go to the Services tab. Create a new service of type SQL (Command) called RunAssignStudentStoredProcedure. Add the following parameter:  Name                      Base Type        Required student_key String True course_key String True 4. Add the following code to your new service: EXECUTE AddStudentsToCourse @person_key = N'<<person_key>>', @course_key = N'<<course_key>>';   You can also perform this execute in a service based on JavaScript using the following code: try { var command = "EXECUTE AddStudentsToCourse " + " @student_key = N'" + student_key + "', " + " @course_key = N'" + course_key + "'"; logger.debug("DatabaseController.RunAssignStudentStoredProcedure(): Command - " + command); var result = me.RunDatabaseCommand({command:command}); } catch(error) { logger.error("DatabaseController.RunAssignStudentStoredProcedure(): Error - " + error.message); } 5. Click Save and Continue. Execute Stored Procedure for Data Let's create the entity you will use for both methods. This can be seen in the example below:   In the DatabaseController entity, go to the Services tab. Create a new service of type SQL (Query) called GetStudentCoursesStoredProcedure. Set the Output as InfoTable, but do not set the DataShape for the InfoTable. Add the following parameter:  Name                    Base Type        Required course_key String True 5. Add the following code to your new service: EXEC GetStudentsInCourse @course_key = N'<<course_key>>'   You can also perform this execute in a service based on JavaScript using the following code: try { var query = "EXEC GetStudentsInCourse " + " @course_key = N'" + course_key + "'"; logger.debug("DatabaseController.GetStudentCoursesStoredProcedure(): Query - " + query); var result = me.RunDatabaseQuery({query:query}); } catch(error) { logger.error("DatabaseController.GetStudentCoursesStoredProcedure(): Error - " + error.message); } 6. Click Save and Continue. You've now created your first set of services used to call stored procedures for data. Of course, these stored procedures will need to be in the database before they can successfully run. Step 6: Next Steps Congratulations! You've successfully completed the guide for External Database, and learned how to use the ThingWorx Platform to connect to database, query for data, and write new data. Learn More We recommend the following resources to continue your learning experience:  Capability       Guide Build Design Your Data Model Build Configure Permissions Additional Resources If you have questions, issues, or need additional information, refer to:  Resource           Link Community Developer Community Forum

    Step 8: Tasks   If you are using the built-in Tasker to drive data collection or other types of repetitive or periodic activities, create a function for the task. Task functions are registered with the Tasker and then called at the rate specified after they are registered. The Tasker is a very simple, cooperative multitasker, so these functions should not take long to return and most certainly must not go into an infinite loop.   The signature for a task function is found in [C SDK HOME DIR]/src/utils/twTasker.h. The function is passed a DATETIME value with the current time and a void pointer that is passed into the Tasker when the task is registered. After creating this function, it will need to be registered using the twApi_CreateTask function after the connection is created. Below shows an example of creating this function, registering this function, and how this function can be used.   #define DATA_COLLECTION_RATE_MSEC 2000 void dataCollectionTask(DATETIME now, void * params) { /* TW_LOG(TW_TRACE,"dataCollectionTask: Executing"); */ properties.TotalFlow = rand()/(RAND_MAX/10.0); properties.Pressure = 18 + rand()/(RAND_MAX/5.0); properties.Location.latitude = properties.Location.latitude + ((double)(rand() - RAND_MAX))/RAND_MAX/5; properties.Location.longitude = properties.Location.longitude + ((double)(rand() - RAND_MAX))/RAND_MAX/5; properties.Temperature = 400 + rand()/(RAND_MAX/40); /* Check for a fault. Only do something if we haven't already */ if (properties.Temperature > properties.TemperatureLimit && properties.FaultStatus == FALSE) { twInfoTable * faultData = 0; char msg[140]; properties.FaultStatus = TRUE; properties.InletValve = TRUE; sprintf(msg,"%s Temperature %2f exceeds threshold of %2f", thingName, properties.Temperature, properties.TemperatureLimit); faultData = twInfoTable_CreateFromString("message", msg, TRUE); twApi_FireEvent(TW_THING, thingName, "SteamSensorFault", faultData, -1, TRUE); twInfoTable_Delete(faultData); } /* Update the properties on the server */ sendPropertyUpdate(); } … twApi_CreateTask(DATA_COLLECTION_RATE_MSEC, dataCollectionTask); … while(1) { char in = 0; #ifndef ENABLE_TASKER DATETIME now = twGetSystemTime(TRUE); twApi_TaskerFunction(now, NULL); twMessageHandler_msgHandlerTask(now, NULL); if (twTimeGreaterThan(now, nextDataCollectionTime)) { dataCollectionTask(now, NULL); nextDataCollectionTime = twAddMilliseconds(now, DATA_COLLECTION_RATE_MSEC); } #else in = getch(); if (in == 'q') break; else printf("\n"); #endif twSleepMsec(5); }      Step 9: File Transfer Example    To handle file transfers, a virtual directory is created in the SteamSensor1 entity and in the [C SDK HOME DIR]/examples/FileTransferExample application directory. The source code used for this example is found in [C SDK HOME DIR]/examples/FileTransferExample/src/main.c.   Inside of the [C SDK HOME DIR]/examples/FileTransferExample folder, create the folder structure shown below: /transfer/ /transfer/incoming/ /transfer/outgoing/ Inside of the /transfer/outgoing/ directory, create and open a file with the name outgoing.txt. Once the outgoing.txt document is open, add the following text, save, and close the file: Hello. This is a file coming from the client application. Navigate to the [C SDK HOME DIR]/examples/FileTransferExample/src/main.c code and update the lines below with the appropriate information for your IP, port, and the “admin_key” Application Key’s keyId value in the ThingWorx Composer: /* Server Details */ #define TW_HOST "127.0.0.1" #define TW_PORT 80 #define TW_APP_KEY "ce22e9e4-2834-419c-9656-ef9f844c784c" To support file transfers in your client application, you must use the twFileManager_AddVirtualDir function in order to create the virtual directories in the entity with such a capability. It will also define the directories available for file operations. A virtual directory maps a unique name to an absolute path of a directory in the file system. All subdirectories of the specified directory are exposed to the server. You can define multiple virtual directories. The directories do not need to be contiguous.   Staging Directory   As an optional, but recommended step, you should set the directory that the application should use for staging when performing file transfers. This can be seen in the line below and should be done before initializing the FileManager. The default directory of the FileManager is most likely owned by root and will require a change to either the location of the staging directory and the ownership of the staging directory, or running the application as a User with the correct permissions.   twcfg.file_xfer_staging_dir = "staging"; The example provided uses the TW_SHARE_DIRECTORY macro to create two virtual directories that will act as the root directories in the virtual file system of this application are added. The client is then started as follows with the necessary TW_ADD_FILE_TRANSFER_SHAPE function being called: TW_ADD_FILE_TRANSFER_SHAPE(); TW_SHARE_DIRECTORY("in", "/transfer/incoming/"); TW_SHARE_DIRECTORY("out", "/transfer/outgoing/"); The creations of the payloads used to create the remote directories on the platform have been moved to a helper function below to make the design cleaner: int setupSystemRepo(const char * remoteInPath, const char * remoteOutPath, const char * remoteFile); After our remote directories and files have been setup, it is time to perform the file transfers. Normally, this would mean invoking the Copy service for a Subsystem, but two functions have been created to make this process easier: int twFileManager_GetFile(const char * sourceRepo, const char * sourcePath, const char * sourceFile, const char * targetRepo, const char * targetPath, const char * targetFile, uint32_t timeout, char asynch, char ** tid) int twFileManager_SendFile(const char * sourceRepo, const char * sourcePath, const char * sourceFile, const char * targetRepo, const char * targetPath, const char * targetFile, uint32_t timeout, char asynch, char ** tid) The table below displays an example of the first set of parameters:    Parameter     Example                             Description sourceRepo SystemRepository The name of FileRepository or RemoteThing to transfer the file FROM. sourcePath outgoing The path specifying the location of the source file. sourceFile The name of the source file.   targetRepo SteamSensor1 The name of FileRepository or RemoteThing to transfer the file TO. targetPath incoming The path specifying the destination location of the file. targetFile incoming.txt The name of the file at the target. This name can differ from the sourceName. timeout 15,000 The amount of time (in seconds) to wait for a synchronous transfer to complete before cancelling the transfer. async false If false, the service call will block for timeout seconds or until the transfer completes. tid incoming0123 The unique TID associated with the file.   The C SDK also provides the ability to create a FileCallback function that the FileManager will call that function when any file transfer events occur. You can provide a wildcard filter so that only file transfer Events of files that match the filter call the callback function. In addition, callbacks can be set up as “one-shots” such that the callback is unregistered automatically after it is invoked the first time.   NOTE: An optional file transfer callback is registered in the code and provided. You will see the output from the function as files are sent and received.   After running this application, you will notice a new file in the transfer/incoming folder after refreshing. This is the file that we created in the ThingWorx Composer file system for the SystemRepository Entity and was able to copy from that location to our local project. We have also sent a file to the server’s SystemRepository. The BrowseFileSystem and GetFileListing services can be used to check for the folders and files created.   twFileManager_RegisterFileCallback(fileCallbackFunc, NULL, FALSE, NULL);     Step 10: Support Other Platforms   All Websocket errors indicate some general issue communicating with the ThingWorx platform. If you experience an issue connecting, refer to the table below for a list of websocket errors, their corresponding codes, and an explanation of the issue.    Code     Message                                                                      Troubleshooting 200 TW_UNKNOWN_WEBSOCKET_ERROR An unknown error occurred on the websocket. 201 TW_ERROR_INITIALIZING_WEBSOCKET An error occurred while initializing the websocket. Check your websocket configuration parameters for validity. 202 TW_TIMEOUT_INITIALIZING_WEBSOCKET A timeout occurred while initializing the websocket. Check the status of the connection to ThingWorx. 203 TW_WEBSOCKET_NOT_CONNECTED The websocket is not connected to ThingWorx. The requested operation cannot be performed. 204 TW_ERROR_PARSING_WEBSOCKET_DATA An error occurred while parsing websocket data. The parser could not break down the data from the websocket. 205 TW_ERROR_READING_FROM_WEBSOCKET An error occurred while reading data from the websocket. Retry the read operation. If necessary, resend the data. 206 TW_WEBSOCKET_FRAME_TOO_LARGE The SDK is attempting to send a websocket frame that is too large. The Maximum Frame Size is set when calling twAPI_Initialize and should always be set to the Message Chunk Size (twcfg.message_chunk_size). 207 TW_INVALID_WEBSOCKET_FRAME_TYPE The type of the frame coming in over the websocket is invalid. 208 TW_WEBSOCKET_MSG_TOO_LARGE The application is attempting to send a message that has been broken up in to chunks that are too large to fit in a frame. You should not see this error. 209 TW_ERROR_WRITING_TO_WEBSOCKET An error occurred while writing to the Web socket. 210 TW_INVALID_ACCEPT_KEY The Accept key sent earlier from ThingWorx is not valid.     Step 11: Next Steps   Congratulations! You've successfully completed the Low Level Device Connect Guide, and learned how to utilize the resources provided in the Edge SDK to create your own application.   The next guide in the Utilizing ThingWorx to Secure Your Aerospace and Defense Systems learning path is Tracking Activities and Statistics.    Learn More   We recommend the following resources to continue your learning experience:    Capability      Guide Build Design Your Data Model Build Implement Services, Events, and Subscriptions   Additional Resources   If you have questions, issues, or need additional information, refer to:    Resource       Link Community Developer Community Forum Support C Edge SDK Help Center      

    Send data from an MXChip Developer kit to your Azure IoT Hub   GUIDE CONCEPT   Users of the MXChip IoT DevKit (a.k.a. MXChip), follow these quick steps to send temperature and humidity data from built-in IoT DevKit sensors to the Azure IoT Hub.   YOU'LL LEARN HOW TO   Connect the IoT DevKit to a wireless access point Create an Azure IoT Hub and register a device for the IoT DevKit Connect IoT Devkit to Azure IoT Hub   NOTE: This guide's content aligns with ThingWorx 9.3. The estimated time to complete this guide is 80 minutes   Step 1: Create an Azure IoT Hub   Choose +Create a resource, then choose Internet of Things. Click Iot Hub from the list on the right. You see the first screen for creating an IoT hub.   Fill in the fields.   Subscription: Select the subscription to use for your IoT hub.   Resource Group: You can create a new resource group or use an existing one. To create a new one, click Create new and fill in the name you want to use. To use an existing resource group, click Use existing and select the resource group from the dropdown list.   Region: This is the region in which you want your hub to be located. Select the location closest to you from the dropdown list.   IoT Hub Name: Put in the name for your IoT Hub. This name must be globally unique. If the name you enter is available, a green check mark appears.         3. Click Next: Size and scale to continue creating your IoT hub.     On this screen, you can take the defaults and just click Review + create at the bottom.   Pricing and scale tier: You can choose from several tiers depending on how many features you want and how many messages you send through your solution per day. The free tier is intended for testing and evaluation. It allows 500 devices to be connected to the IoT hub and up to 8,000 messages per day. Each Azure subscription can create one IoT Hub in the free tier.   IoT Hub units: The number of messages allowed per unit per day depends on your hub’s pricing tier. For example, if you want the IoT hub to support ingress of 700,000 messages, you choose two S1 tier units.   Advanced / Device-to-cloud partitions: This property relates the device-to-cloud messages to the number of simultaneous readers of the messages. Most IoT hubs only need four partitions.               4. Click Review + create to review your choices. You see something similar to this screen.           5. Click Create to create your new IoT hub. Creating the hub takes a few minutes.     Step 2: Create IoT device   Navigate to the IoT Hub created and in the IoT Devices page, click + New.   2. Enter the device ID used by the demo MXChip application MyNodeDevice. Use the default settings for auto-generating authentication keys and connecting the new device to your hub. Click Save.   3. Navigate to the device created and make a note of the device connection string, which looks like: HostName={YourIoTHubName}.azure-devices.net;DeviceId=MyNodeDevice;SharedAccessKey={YourSharedAccessKey}.   Create Azure Storage   The ThingWorx Azure IoT Connector we will install in the next guide requires an Azure Storage Account. Follow the Microsoft documentation to create an Azure Storage account. NOTE: Select Blob storage as the account type and the Hot Access Tier.     Step 3: Connect to Azure IoT Hub   Download the latest version of GetStarted firmware for IoT DevKit. Connect IoT DevKit to your computer via USB. In Windows you see a new USB mass storage device in Windows Explorer called AZ3166. Drag and drop the .bin file you downloaded from step 1 into the disk named AZ3166 and wait for IoT Devkit to restart. Internet connectivity is required to connect to Azure IoT Hub. Use AP Mode on the DevKit to configure and connect to Wi-Fi.Hold down button B, push and release the Reset button, and then release button B. Your IoT DevKit enters AP mode for configuring the Wi-Fi connection. The screen displays the service set identifier (SSID) of the DevKit and the configuration portal IP address:     5. Use a Web browser on a different Wi-Fi enabled device (computer or mobile phone) to connect to the IoT DevKit SSID displayed in the previous step. If it asks for a password, leave it empty.     6. Open 192.168.0.1 in the browser. Select or input the Wi-Fi network that you want the IoT DevKit to connect to, type the password for the Wi-Fi conection and input the device connection string you made notge of in step 1. Then click Connect.     7. The WiFi credentials and device connection string will be saved in the IoT DevKit even after power cycliong. The following page will be displayed in the browser:     8. The IoT DevKit reboots in a few seconds. You then see the assigned Wi-Fi IP address on the screen of the IoT DevKit:     9. Wait for the IoT DevKit to connect to Azure IoT Hub and you will see it sending telemetry data including temperature and humidity value to Azure IoT Hub. The screen of the IoT Devkit would show message count and temperature/humidity data.       Step 4: Next Steps   Congratulations! You've successfully completed the Connect MXChip to Azure IoT guide. By following the steps in this lesson, you created an Azure IoT Hub and device.     The next guide in the Azure MXChip Development Kit learning path is Create an Application Key.   Learn More   We recommend the following resources to continue your learning experience:   Capability Guide Analyze Build a Predictive Analytics Model Build Get Started with ThingWorx for IoT   Additional Resources   If you have questions, issues, or need additional information, refer to:   Resource Link Community Developer Community Forum Support Azure Support Page    

  Send voice and text messages with Twilio.   GUIDE CONCEPT   This project will demonstrate how you can create applications that provide information to users, even when they are away from their computer. Users who are on the go can benefit from your application by receiving text and voice messages.   Following the steps in this guide, you will learn how to configure and use the Twilio Widget and explore it’s ability to send messages.   We will teach you how data can be used to send pertinent information to any cell phone.   YOU'LL LEARN HOW TO   Download and import the Twilio Widget extension Create a Thing using the Twilio Thing Template Configure the Twilio Thing to use your Twilio account Send text messages using a Service   NOTE:  The estimated time to complete this guide is 30 minutes.     Step 1: Install Twilio Extension   Download the Twilio Extension from IQNOX.com. Note:  IQNOX is a PTC Partner and will be maintaining and supporting specific extensions going forward.  It will be necessary to create an account on the IQNOX website, but the ThingWorx extensions are free. In the lower-left side of Composer, click Import/Export, then Import.   In the Import From File pop-up, under Import Option select Extension from the drop-down, then click Browse. Navigate to the .zip file you downloaded.   Click Import in the Import From File pop-up, then click Close after file is successfully imported.     Step 2: Create Twilio Thing   In this step, you will create a Thing that represents a connection with the Twilio service.   Start on the Browse, folder icon tab on the far left of ThingWorx Composer.  Under the Modeling tab, hover over Things then click the + button. Type twilio-connector in the Name field.   NOTE: This name, with matching capitalization, is required for the example code which will be entered in a later step. If Project is not already set, click the + in the Project text box and select the PTCDefaultProject. In the Base Thing Template text box, click the + and select Twilio.     Click Save.     Step 3: Configure Twilio Thing   Now that we have created a Thing to represent the Twilio connection, we will configure it with your Twilio account credentials.   When the Twilio Extension is installed, it does not include the Twilio account credentials required to send messages.   You will need Twilio account credentials to complete this step. If you do not already have a Twilio account, you can click on this link to create a Twilio account.   Open the twilio-connection Thing if it is not already open. Click on the Configuration tab. Click the pencil icon next to the authToken field.   Copy your AUTH TOKEN from your Twilio account dashboard.   Paste your AUTH TOKEN into the New Password and Confirm Password fields under authToken.   Click the pencil icon next to the accountSID field. Copy your ACCOUNT SID from your Twilio account dashboard, and paste it into the New Password and Confirm Password fields under accountSID. Follow the steps in your Twilio account dashboard to get a trial phone number.   Copy your PHONE NUMBER from your Twilio account dashboard, and paste it into the callerID field.   Click Save.     Step 4: Test Twilio Thing   Now that we have created a Thing to represent the Twilio connection and configured it with Twilio account credentials, we will confirm that everything is working.   Click the Services tab at the top of the twilio-connector Thing.     Click the link to the SendSMSMessage Service in the Services Name column. Enter a phone number in the to field. Enter a test message in the text field.   Click the Execute button to send the SMS message. The service should execute without any errors within a couple of seconds and the phone number will receive your message. Click Close to end testing the service.     Step 5: Sample Alerting App   At this point, you have created and tested a Thing that can send text messages. This step will demonstrate sending a message when a Property Value is out of the desired range.   Import Simulated Freezer Thing   Download and unzip the attached sample Things_freezer.zip. In Composer, click the Import/Export icon at the lower-left of the page.   Click Import. Leave all default values and click Browse to select the Things_freezer.twx file that you just downloaded. Click Open, then Import. When you see the success message, click Close.   Explore Imported Entities   Navigate to the freezer Thing by using the search bar at the top of the screen. Click the Subscriptions tab.   Click reportFreezer under Name. Open the Subscription Info tab. Select the Enabled checkbox.   Click Done then Save to save any changes.   Verify Data Simulation   Open the freezer Thing and click Properties and Alerts tab. Click the Set value in the alertedPhone Property row, in the Value column.   Enter a phone number to receive the SMS alert, then click the Check icon above where you entered the phone number. Click the pencil icon in the temp Property row, in the Value column. Enter a value for the temp property that is greater than 30, and click the Check icon. In a couple seconds, the phone number you entered will receive an alert that includes the value you entered.      Step 6: Next Steps   Congratulations!   In this guide, you learned how to:   Create a Thing using the Twilio Thing Template Configure the Twilio Thing to use your Twilio account Send text messages using a Service   Additional Resources   If you have questions, issues, or need additional information, refer to:   Resource Link Community Developer Community Forum Support Twilio Extension Help Center

  Use the C SDK to build an app that connects to ThingWorx with persistent bi-directional communication.     GUIDE CONCEPT   This project will introduce more complex aspects of the ThingWorx C SDK and help you to get started with development.   Following the steps in this this guide, you will be ready to develop your own IoT application with the ThingWorx C SDK.   We will teach you how to use the C programming language to connect and build IoT applications to be used with the ThingWorx Platform.   YOU'LL LEARN HOW TO   Establish and manage a secure connection with a ThingWorx server, including SSL negotiation and connection maintenance Enable easy programmatic interaction with the Properties, Services, and Events that are exposed by Entities running on a ThingWorx server Create applications that can be directly used with your device running the C programming language Basic concepts of the C Edge SDK How to use the C Edge API to build a real-world application How to utilize resources provided in the Edge SDK to help create your own application    Note: The estimated time to complete ALL 4 parts of this guide is 60 minutes.      Step 1: Completed Examples   Download the completed files for this tutorial: ThingWorx C Edge SDK Sample Files.zip.   This tutorial will guide you through working with the C SDK on differing levels. Utilize this file to see a finished example and return to it as a reference if you become stuck creating your own fully fleshed out application.   Keep in mind, this download uses the exact names for Entities used in this tutorial. If you would like to import this example and also create Entities on your own, change the names of the Entities you create.     Step 2: Environment Setup   In order to compile C code, you need a C compiler and the ThingWorx C Edge SDK. It will be helpful to have CMake installed on your system. CMake is a build tool that will generate make or project files for many different platforms and IDEs.   Operating System Notes Windows You will need a 3rd party compiler such as MinGW GCC, Cygwin GCC or you can follow these Microsoft instructions to download and use the Microsoft Visual C++ Build Tool. Mac Download the Apple Developer Tools. Linux/Ubuntu A compiler is included by default.   NOTE: You can use CMake, version 2.6.1 or later to build projects or make files, which then are used to build the applications that you develop with the C SDK.   Before you can begin developing with the ThingWorx C SDK, you need to generate an Application Key and modify the source code file. You can use the Create an Application Key guide as a reference.   Modify Source File   Extract the files from the C SDK samples zip file. At the top level of the extracted files, you will see a folder called examples. This directory provides examples of how to utilize the C SDK. Open a terminal, go to your workspace, and create a new directory. You can also just switch to the unzipped directory in your system. After you've created this directory in your workspace, copy the downloaded files and folders into your new directory. You can start creating your connection code or open the main.c source file in the examples\SteamSensor\src directory for an example.   Operating System Code Linux/Ubuntu gedit main.c OR vi main.c Mac open –e main.c Windows start main.c        5. Modify the Server Details section at the top with the IP address for your ThingWorx Platform instance and the Application Key you would like to use.   Change the TW_HOST definition accordingly. Change the TW_PORT definition accordingly. Change the TW_APP_KEY definition to the keyId value saved from the last step.   /* Server Details */ #define TW_HOST "https://pp-XXXXXXXXX.devportal.ptc.i" #define TW_PORT 80 #define TW_APP_KEY "e1d78abf-cfd2-47a6-92b7-37ddc6dd34618" NOTE: Using the Application Key for the default Administrator is not recommended. If administrative access is absolutely necessary, create a User and place the user as a member of Admins.   Compile and Run Code   To test your connection, you will only need to update the main.c in the SteamSensor example folder. CMake can generate Visual Studio projects, make build files or even target IDEs such as Eclipse, or XCode. CMake generates a general description into a build for your specific toolchain or IDE.   Inside the specific example folder you would like to run, ie SteamSensor. Create a directory to build in, for this example call it bin. mkdir bin  cd bin      5. Run the CMake command listed below. This assumes CMake is already on your PATH. cmake ..      6. CMake has now produced a set of project files which should be compatible with your development environment.   Operating System Command Note Unix make A set of make files Windows msbuild tw-c-sdk.sln /t:build A visual studio solution   NOTE: CMake does its best to determine what version of Visual Studio you have but you may wish to specify which version to use if you have more than one installed on your computer. Below is an example of forcing CMake to use a specific version of Visual Studio: cmake -G "Visual Studio 15 2017" .. If your version of Visual Studio or other IDE is unknown, use cmake -G to see a list of supported IDEs.   You also have the alternative of opening the tw-c-sdk.sln from within Visual Studio and building in this IDE.   NOTE: By default, CMake will generate a build for the creation of a release binary. If you want to generate a debug build, use the command-> cmake -DBUILD_DEBUG=ON ..       7. Once your build completes you will find the build products in the CMake directory (see example below). From here, open the project in your IDE of choice.   NOTE: You should receive messages confirming successful binding, authentication, and connection after the main.c file edits have been made.   Operating System Files Description Unix ./bin/src/libtwCSdk_static.a  Static Library Unix ./bin/src/libtwCSdk.so  Shared Library Unix ./bin/examples/SteamSensor/SteamSensor   Sample Application Windows .\bin\src\<Debug/Release>\twCSdk_static.lib  Static Library Windows .\bin\src\<Debug/Release>\twCSdk.dll  Shared Library Windows .\bin\examples\<Debug/Release>\SteamSensor\SteamSensor.exe  Sample Application     Step 3: Run Sample Code   The C code in the sample download is configured to run and connect to the Entities provided in the ThingWorxEntitiesExport.xml file. Make note of the IP address of your ThingWorx Composer instance. The top level of the exported zip file will be referred to as [C SDK HOME DIR].   Navigate to the [C SDK HOME DIR]/examples/ExampleClient/src directory. Open the main.c source file.   Operating System Command Linux/Ubuntu gedit main.c OR vi main.c Mac open –e main.c Windows start main.c   Modify the Server Details section at the top with the IP address for your ThingWorx Platform instance and the Application Key you would like to use. Change the TW_HOST definition accordingly.   NOTE: By default, TW_APP_KEY has been set to the Application Key from the admin_key in the import step completed earlier. Using the Application Key for the default Administrator is not recommended. If administrative access is absolutely necessary, create a user and place the user as a member of the Admins security group.   /* Server Details */ #define TW_HOST "127.0.0.1" #define TW_APP_KEY "ce22e9e4-2834-419c-9656-e98f9f844c784c"   If you are working on a port other than 80, you will need to update the conditional statement within the main.c source file. Search for and edit the first line within the main function. Based on your settings, set the int16_t port to the ThingWorx platform port. Click Save and close the file. Create a directory to build in, for this example call it bin.   Operating System Command Linux/Ubuntu mkdir bin Mac mkdir bin Windows mkdir bin   Change to the newly created bin directory.   Operating System Command Linux/Ubuntu cd bin Mac cd bin Windows cd bin   Run the CMake command using your specific IDE of choice.    NOTE: Include the two periods at the end of the code as shown below. Use cmake -G to see a list of supported IDEs.   cmake ..   Once your build completes, you will find the build products in the bin directory, and you can open the project in your IDE of choice. NOTE: You should receive messages confirming successful binding, authentication, and connection after building and running the application    10. You should be able to see a Thing in your ThingWorx Composer called SimpleThing_1 with updated last Connection and isConnected properties. SimpleThing_1 is bound for the duration of the application run time                                                                                                                                                                                The below instructions will help to verify the connection.   Click Monitoring. Click Remote Things from the list to see the connection status.   You will now be able to see and select the Entity within the list.   Step 4: ExampleClient Connection   The C code provided in the main.c source file is preconfigured to initialize the ThingWorx C Edge SDK API with a connection to the ThingWorx platform and register handlers. In order to set up the connection, a number of parameters must be defined. This can be seen in the code below.   #define TW_HOST "127.0.0.1" #define TW_APP_KEY "ce22e9e4-2834-419c-9656-ef9f844c784c #if defined NO_TLS #define TW_PORT = 80; #else #define TW_PORT = 443; #endif The first step of connecting to the platform: Establish Physical Websocket, we call the   twApi_Initialize function with the information needed to point to the websocket of the ThingWorx Composer. This function:   Registers messaging handlers Allocates space for the API structures Creates a secure websocket   err = twApi_Initialize(hostname, port, TW_URI, appKey, NULL, MESSAGE_CHUNK_SIZE, MESSAGE_CHUNK_SIZE, TRUE); if (TW_OK != err) { TW_LOG(TW_ERROR, "Error initializing the API"); exit(err); }   If you are not using SSL/TLS, use the following line to test against a server with a self-signed certificate:   twApi_SetSelfSignedOk();   In order to disable HTTPS support and use HTTP only, call the twApi_DisableEncryption function. This is needed when using ports such as 80 or 8080. A call can be seen below:   twApi_DisableEncryption();   The following event handlers are all optional. The twApi_RegisterBindEventCallback function registers a function that will be called on the event of a Thing being bound or unbound to the ThingWorx platform. The twApi_RegisterOnAuthenticatedCallback function registered a function that will be called on the event the SDK has been authenticated by the ThingWorx Platform.  The twApi_RegisterSynchronizeStateEventCallback function registers a function that will be called after binding and used to notify your application about fields that have been bound to the Thingworx Platform.   twApi_RegisterOnAuthenticatedCallback(authEventHandler, TW_NO_USER_DATA); twApi_RegisterBindEventCallback(NULL, bindEventHandler, TW_NO_USER_DATA); twApi_RegisterSynchronizeStateEventCallback(NULL, synchronizeStateHandler, TW_NO_USER_DATA);   NOTE: Binding a Thing within the ThingWorx platform is not mandatory, but there are a number of advantages, including updating Properties while offline.   You can then start the client, which will establish the AlwaysOn protocol with the ThingWorx Composer. This protocol provides bi-directional communication between the ThingWorx Composer and the running client application. To start this connection, use the line below:   err = twApi_Connect(CONNECT_TIMEOUT, RETRY_COUNT); if(TW_OK != err){ exit(-1); }     Click here to view Part 2 of this guide

  Step 6: Data Shapes   Data Shapes are an important part of creating/firing Events and also invoking Services   Define With Macros   In order to define a Data Shape using a macro, use TW_MAKE_DATASHAPE.   NOTE: The macros are all defined in the twMacros.h header file.   TW_MAKE_DATASHAPE("SteamSensorReadingShape", TW_DS_ENTRY("ActivationTime", TW_NO_DESCRIPTION ,TW_DATETIME), TW_DS_ENTRY("SensorName", TW_NO_DESCRIPTION ,TW_NUMBER), TW_DS_ENTRY("Temperature", TW_NO_DESCRIPTION ,TW_NUMBER), TW_DS_ENTRY("Pressure", TW_NO_DESCRIPTION ,TW_NUMBER), TW_DS_ENTRY("FaultStatus", TW_NO_DESCRIPTION ,TW_BOOLEAN), TW_DS_ENTRY("InletValve", TW_NO_DESCRIPTION ,TW_BOOLEAN), TW_DS_ENTRY("TemperatureLimit", TW_NO_DESCRIPTION ,TW_NUMBER), TW_DS_ENTRY("TotalFlow", TW_NO_DESCRIPTION ,TW_INTEGER) );   Define Without Macros   In order to define a Data Shape without using a macro, use the  twDataShape_CreateFromEntries  function. In the example below, we are creating a Data Shape called SteamSensorReadings that has two numbers as Field Definitions.   twDataShape * ds = twDataShape_Create(twDataShapeEntry_Create("a",NULL,TW_NUMBER)); twDataShape_AddEntry(ds, twDataShapeEntry_Create("b",NULL,TW_NUMBER)); /* Name the DataShape for the SteamSensorReadings service output */ twDataShape_SetName(ds, "SteamSensorReadings");     Step 7: Events and Services   Events and Services provide useful functionality. Events are a good way to make a Service be asynchronous. You can call a Service, let it return, then your Entity can subscribe to your Event and not keep the original Service function waiting. Events are also a good way to allow the platform to respond to data when it arrives on the edge device without it having to poll the edge device for updates.   Fire Events   To fire an Event you first need to register the Event and load it with the necessary fields for the Data Shape of that Event using the twApi_RegisterEvent function. Afterwards, you would send a request to the ThingWorx server with the collected values using the twApi_FireEvent function. An example is as follows:   twDataShape * ds = twDataShape_Create(twDataShapeEntry_Create("message", NULL,TW_STRING)); /* Event datashapes require a name */ twDataShape_SetName(ds, "SteamSensorFault"); /* Register the service */ twApi_RegisterEvent(TW_THING, thingName, "SteamSensorFault", "Steam sensor event", ds); …. struct { char FaultStatus; double Temperature; double TemperatureLimit; } properties; …. properties. TemperatureLimit = rand() + RAND_MAX/5.0; properties.Temperature = rand() + RAND_MAX/5.0; properties.FaultStatus = FALSE; if (properties.Temperature > properties.TemperatureLimit && properties.FaultStatus == FALSE) { twInfoTable * faultData = 0; char msg[140]; properties.FaultStatus = TRUE; sprintf(msg,"%s Temperature %2f exceeds threshold of %2f", thingName, properties.Temperature, properties.TemperatureLimit); faultData = twInfoTable_CreateFromString("message", msg, TRUE); twApi_FireEvent(TW_THING, thingName, "SteamSensorFault", faultData, -1, TRUE); twInfoTable_Delete(faultData); }   Invoke Services   In order to invoke a Service, you will use the twApi_InvokeService function. The full documentation for this function can be found in [C SDK HOME DIR]/src/api/twApi.h. Refer to the table below for additional information.   Parameter Type Description entityType Input The type of Entity that the service belongs to. Enumeration values can be found in twDefinitions.h. entityName Input The name of the Entity that the service belongs to. serviceName Input The name of the Service to execute. params Input A pointer to an Info Table containing the parameters to be passed into the Service. The calling function will retain ownership of this pointer and is responsible for cleaning up the memory after the call is complete. result Input/Output A pointer to a twInfoTable pointer. In a successful request, this parameter will end up with a valid pointer to a twInfoTable that is the result of the Service invocation. The caller is responsible for deleting the returned primitive using twInfoTable_Delete. It is possible for the returned pointer to be NULL if an error occurred or no data is returned. timeout Input The time (in milliseconds) to wait for a response from the server. A value of -1 uses the DEFAULT_MESSAGE_TIMEOUT as defined in twDefaultSettings.h. forceConnect Input A Boolean value. If TRUE and the API is in the disconnected state of the duty cycle, the API will force a reconnect to send the request.   See below for an example in which the Copy service from the FileTransferSubsystem is called:   twDataShape * ds = NULL; twInfoTable * it = NULL; twInfoTableRow * row = NULL; twInfoTable * transferInfo = NULL; int res = 0; const char * sourceRepo = "SimpleThing_1"; const char * sourcePath = "tw/hotfolder/"; const char * sourceFile = "source.txt"; const char * targetRepo = "SystemRepository"; const char * targetPath = "/"; const char * targetFile = "source.txt"; uint32_t timeout = 60; char asynch = TRUE; char * tid = 0; /* Create an infotable out of the parameters */ ds = twDataShape_Create(twDataShapeEntry_Create("sourceRepo", NULL, TW_STRING)); res = twDataShape_AddEntry(ds, twDataShapeEntry_Create("sourcePath", NULL, TW_STRING)); res |= twDataShape_AddEntry(ds, twDataShapeEntry_Create("sourceFile", NULL, TW_STRING)); res |= twDataShape_AddEntry(ds, twDataShapeEntry_Create("targetRepo", NULL, TW_STRING)); res |= twDataShape_AddEntry(ds, twDataShapeEntry_Create("targetPath", NULL, TW_STRING)); res |= twDataShape_AddEntry(ds, twDataShapeEntry_Create("targetFile", NULL, TW_STRING)); res |= twDataShape_AddEntry(ds, twDataShapeEntry_Create("async", NULL, TW_BOOLEAN)); res |= twDataShape_AddEntry(ds, twDataShapeEntry_Create("timeout", NULL, TW_INTEGER)); it = twInfoTable_Create(ds); row = twInfoTableRow_Create(twPrimitive_CreateFromString(sourceRepo, TRUE)); res = twInfoTableRow_AddEntry(row, twPrimitive_CreateFromString(sourcePath, TRUE)); res |= twInfoTableRow_AddEntry(row, twPrimitive_CreateFromString(sourceFile, TRUE)); res |= twInfoTableRow_AddEntry(row, twPrimitive_CreateFromString(targetRepo, TRUE)); res |= twInfoTableRow_AddEntry(row, twPrimitive_CreateFromString(targetPath, TRUE)); res |= twInfoTableRow_AddEntry(row, twPrimitive_CreateFromString(targetFile, TRUE)); res |= twInfoTableRow_AddEntry(row, twPrimitive_CreateFromBoolean(asynch)); res |= twInfoTableRow_AddEntry(row, twPrimitive_CreateFromInteger(timeout)); twInfoTable_AddRow(it,row); /* Make the service call */ res = twApi_InvokeService(TW_SUBSYSTEM, "FileTransferSubsystem", "Copy", it, &transferInfo, timeout ? (timeout * 2): -1, FALSE); twInfoTable_Delete(it); /* Grab the tid */ res = twInfoTable_GetString(transferInfo,"transferId",0, &tid);   Bind Event Handling You may want to track exactly when your edge Entities are successfully bound to or unbound from the server. The reason for this is that only bound items should be interacting with the ThingWorx Platform and the ThingWorx Platform will never send any requests targeted at an Entity that is not bound. A simple example that only logs the bound Thing can be seen below. After creating this function, it will need to be registered using the twApi_RegisterBindEventCallback function before the connection is made.   void BindEventHandler(char * entityName, char isBound, void * userdata) { if (isBound) TW_LOG(TW_FORCE,"BindEventHandler: Entity %s was Bound", entityName); else TW_LOG(TW_FORCE,"BindEventHandler: Entity %s was Unbound", entityName); } …. twApi_RegisterBindEventCallback(thingName, BindEventHandler, NULL);   OnAuthenticated Event Handling   You may also want to know exactly when your Edge device has successfully authenticated and made a connection to the ThingWorx platform. Like the bind Event handling, this function will need to be made and registered. To register this handler, use the   twApi_RegisterOnAuthenticated Callback function before the connection is made. This handler form can also be used to do a delay bind for all Things.   void AuthEventHandler(char * credType, char * credValue, void * userdata) { if (!credType || !credValue) return; TW_LOG(TW_FORCE,"AuthEventHandler: Authenticated using %s = %s. Userdata = 0x%x", credType, credValue, userdata); /* Could do a delayed bind here */ /* twApi_BindThing(thingName); */ } … twApi_RegisterOnAuthenticatedCallback(AuthEventHandler, NULL);     Step 8: Tasks   If you are using the built-in Tasker to drive data collection or other types of repetitive or periodic activities, create a function for the task. Task functions are registered with the Tasker and then called at the rate specified after they are registered. The Tasker is a very simple, cooperative multitasker, so these functions should not take long to return and most certainly must not go into an infinite loop.   The signature for a task function is found in [C SDK HOME DIR]/src/utils/twTasker.h. The function is passed a DATETIME value with the current time and a void pointer that is passed into the Tasker when the task is registered. After creating this function, it will need to be registered using the twApi_CreateTask function after the connection is created. Below shows an example of creating this function, registering this function, and how this function can be used.   #define DATA_COLLECTION_RATE_MSEC 2000 void dataCollectionTask(DATETIME now, void * params) { /* TW_LOG(TW_TRACE,"dataCollectionTask: Executing"); */ properties.TotalFlow = rand()/(RAND_MAX/10.0); properties.Pressure = 18 + rand()/(RAND_MAX/5.0); properties.Location.latitude = properties.Location.latitude + ((double)(rand() - RAND_MAX))/RAND_MAX/5; properties.Location.longitude = properties.Location.longitude + ((double)(rand() - RAND_MAX))/RAND_MAX/5; properties.Temperature = 400 + rand()/(RAND_MAX/40); /* Check for a fault. Only do something if we haven't already */ if (properties.Temperature > properties.TemperatureLimit && properties.FaultStatus == FALSE) { twInfoTable * faultData = 0; char msg[140]; properties.FaultStatus = TRUE; properties.InletValve = TRUE; sprintf(msg,"%s Temperature %2f exceeds threshold of %2f", thingName, properties.Temperature, properties.TemperatureLimit); faultData = twInfoTable_CreateFromString("message", msg, TRUE); twApi_FireEvent(TW_THING, thingName, "SteamSensorFault", faultData, -1, TRUE); twInfoTable_Delete(faultData); } /* Update the properties on the server */ sendPropertyUpdate(); } … twApi_CreateTask(DATA_COLLECTION_RATE_MSEC, dataCollectionTask); … while(1) { char in = 0; #ifndef ENABLE_TASKER DATETIME now = twGetSystemTime(TRUE); twApi_TaskerFunction(now, NULL); twMessageHandler_msgHandlerTask(now, NULL); if (twTimeGreaterThan(now, nextDataCollectionTime)) { dataCollectionTask(now, NULL); nextDataCollectionTime = twAddMilliseconds(now, DATA_COLLECTION_RATE_MSEC); } #else in = getch(); if (in == 'q') break; else printf("\n"); #endif twSleepMsec(5); }   Click here to view Part 4 of this guide

  Step 5: Properties   In the Delivery Truck application, there are three Delivery Truck Things. Each Thing has a number of Properties based on its location, speed, and its deliveries carried out. In this design, when a delivery is made or the truck is no longer moving, the Property values are updated.   The deliveryTruck.c helper C file is based on the DeliveryTruck Entities in the Composer. After calling the construct function, there are a number of steps necessary to get going. For the SimpleThing application, there are a number of methods for creating Properties, Events, Services, and Data Shapes for ease of use.   Properties can be created in the client or just registered and utilized. In the  SimpleThingClient  application, Properties are created. In the DeliveryTruckClient application, Properties are bound to their ThingWorx Platform counterpart. Two types of structures are used by the C SDK to define Properties when it is seen fit to do so and can be found in [C SDK HOME DIR]/src/api/twProperties.h:   Name Structure Description Property Definitions twPropertyDef Describes the basic information for the Properties that will be available to ThingWorx and can be added to a client application. Property Values twProperty Associates the Property name with a value, timestamp, and quality.   NOTE: The C SDK provides a number of Macros located in [C SDK HOME DIR]/src/api/twMacros.h. This guide will use these Macros while providing input on the use of pure function calls.   The Macro example below can be found in the main source file for the   SimpleThingClient   application and the accompanying helper file simple_thing.c.   TW_PROPERTY("TempProperty", "Description for TempProperty", TW_NUMBER); TW_ADD_BOOLEAN_ASPECT("TempProperty", TW_ASPECT_ISREADONLY,TRUE); TW_ADD_BOOLEAN_ASPECT("TempProperty", TW_ASPECT_ISLOGGED,TRUE); NOTE: The list of aspect configurations can be seen in [C SDK HOME DIR]/src/api/twConstants.h. Property values can be set with defaults using the aspects setting. Setting a default value in the client will affect the Property in the ThingWorx platform after binding. It will not set a local value in the client application.   For the DeliveryTruckClient, we registered, read, and update Properties without using the Property definitions. Which method of using Properties is based on the application being built.   NOTE: Updating Properties in the ThingWorx Platform while the application is running, will update the values in the client application. To update the values in the platform to match, end the Property read section of your property handler function with a function to set the platform value.   The createTruckThing function for the deliveryTruck.c source code takes a truck name as a parameter and is used to register the Properties, functions, and handlers for each truck.   The updateTruckThing function for the deliveryTruck.c source code takes a truck name as a parameter and is used to either initialize a struct for DeliveryTruck Properties, or simulate a truck stop Event, update Properties, then fire an Event for the ThingWorx platform.   Connecting properties to be used on the platform is as easy as registering the property and optionally adding aspects. The following shows the properties that correlate to those in the DeliveryTruck entities in the Composer. To do this within the code, you would use the  TW_PROPERTY macro as shown in the deliveryTruck.c. This macro must be proceeded by either TW_DECLARE_SHAPE, TW_DECLARE_TEMPLATE or TW_MAKE_THING because these macros declare variables used by the TW_PROPERTY that follow them.   //TW_PROPERTY(propertyName,description,type) TW_PROPERTY(PROPERTY_NAME_DRIVER, NO_DESCRIPTION, TW_STRING); TW_PROPERTY(PROPERTY_NAME_DELIVERIES_LEFT, NO_DESCRIPTION, TW_NUMBER); TW_PROPERTY(PROPERTY_NAME_TOTAL_DELIVERIES, NO_DESCRIPTION, TW_NUMBER); TW_PROPERTY(PROPERTY_NAME_DELIVERIES_MADE, NO_DESCRIPTION, TW_NUMBER); TW_PROPERTY(PROPERTY_NAME_LOCATION, NO_DESCRIPTION, TW_LOCATION); TW_PROPERTY(PROPERTY_NAME_SPEED, NO_DESCRIPTION, "TW_NUMBER);   Read Properties   Reading Properties from a ThingWorx platform Thing or the returned Properties of a Service can be done using the TW_GET_PROPERTY macro. Examples of its use can be seen in all of the provided applications. An example can be seen below:   int flow = TW_GET_PROPERTY(thingName, "TotalFlow").number; int pressue = TW_GET_PROPERTY(thingName, "Pressure").number; twLocation location = TW_GET_PROPERTY(thingName, "Location").location; int temperature = TW_GET_PROPERTY(thingName, "Temperature").number;   Write Properties   Writing Properties to a ThingWorx platform Thing from a variable storing is value uses a similarly named method. Using the TW_SET_PROPERTY macro will be able to send values to the platform. Examples of its use can be seen in all of the provided applications. An example is shown below:   TW_SET_PROPERTY(thingName, "TotalFlow", TW_MAKE_NUMBER(rand() / (RAND_MAX / 10.0))); TW_SET_PROPERTY(thingName, "Pressure", TW_MAKE_NUMBER(18 + rand() / (RAND_MAX / 5.0))); TW_SET_PROPERTY(thingName, "Location", TW_MAKE_LOC(gpsroute[location_step].latitude,gpsroute[location_step].longitude,gpsroute[location_step].elevation));   This macro utilizes the twApi_PushSubscribedProperties function call to pushe all property updates to the server. This can be seen in the updateTruckThing function in deliveryTruck.c.   Property Change Listeners   Using the Observer pattern, you can take advantage of the Property change listener functionality. With this pattern, you create functions that will be notified when a value of a Property has been changed (whether on the server or locally by your program when the TW_SET_PROPERTY macro is called).   Add a Property Change Listener   In order to add a Property change listener, call the twExt_AddPropertyChangeListener function using the:   Name of the Thing (entityName) Property this listener should watch Function that will be called when the property has changed void simplePropertyObserver(const char * entityName, const char * thingName,twPrimitive* newValue){ printf("My Value has changed\n"); } void test_simplePropertyChangeListener() { { TW_MAKE_THING("observedThing",TW_THING_TEMPLATE_GENERIC); TW_PROPERTY("TotalFlow", TW_NO_DESCRIPTION, TW_NUMBER); } twExt_AddPropertyChangeListener("observedThing",TW_OBSERVE_ALL_PROPERTIES,simplePropertyObserver); TW_SET_PROPERTY("observedThing","TotalFlow",TW_MAKE_NUMBER(50)); }   NOTE: Setting the propertyName parameter to NULL or TW_OBSERVE_ALL_PROPERTIES, the function specified by the propertyChangeListenerFunction parameter will be used for ALL properties.   Remove a Property Change Listener   In order to release the memory for your application when done with utilizing listeners for the Property, call the twExt_RemovePropertyChangeListener function.   void simplePropertyObserver(const char * entityName, const char * thingName,twPrimitive* newValue){ printf("My Value has changed\n"); } twExt_RemovePropertyChangeListener(simplePropertyObserver);   Click here to view Part 3 of this guide  

  Step 9: File Transfer Example   To handle file transfers, a virtual directory is created in the SteamSensor1 entity and in the [C SDK HOME DIR]/examples/FileTransferExample application directory. The source code used for this example is found in [C SDK HOME DIR]/examples/FileTransferExample/src/main.c.   Inside of the [C SDK HOME DIR]/examples/FileTransferExample folder, create the folder structure shown below:   /transfer/ /transfer/incoming/ /transfer/outgoing/   Inside of the /transfer/outgoing/ directory, create and open a file with the name outgoing.txt. Once the outgoing.txt document is open, add the following text, save, and close the file: Hello. This is a file coming from the client application. Navigate to the [C SDK HOME DIR]/examples/FileTransferExample/src/main.c code and update the lines below with the appropriate information for your IP, port, and the “admin_key” Application Key’s keyId value in the ThingWorx Composer:   /* Server Details */ #define TW_HOST "127.0.0.1" #define TW_PORT 80 #define TW_APP_KEY "ce22e9e4-2834-419c-9656-ef9f844c784c"   To support file transfers in your client application, you must use the   twFileManager_AddVirtualDir function in order to create the virtual directories in the entity with such a capability. It will also define the directories available for file operations. A virtual directory maps a unique name to an absolute path of a directory in the file system. All subdirectories of the specified directory are exposed to the server. You can define multiple virtual directories. The directories do not need to be contiguous. Staging Directory   As an optional, but recommended step, you should set the directory that the application should use for staging when performing file transfers. This can be seen in the line below and should be done before initializing the FileManager. The default directory of the FileManager is most likely owned by root and will require a change to either the location of the staging directory and the ownership of the staging directory, or running the application as a User with the correct permissions.   twcfg.file_xfer_staging_dir = "staging";   The example provided uses the TW_SHARE_DIRECTORY macro to create two virtual directories that will act as the root directories in the virtual file system of this application are added. The client is then started as follows with the necessary TW_ADD_FILE_TRANSFER_SHAPE function being called:   TW_ADD_FILE_TRANSFER_SHAPE(); TW_SHARE_DIRECTORY("in", "/transfer/incoming/"); TW_SHARE_DIRECTORY("out", "/transfer/outgoing/");   The creations of the payloads used to create the remote directories on the platform have been moved to a helper function below to make the design cleaner:   int setupSystemRepo(const char * remoteInPath, const char * remoteOutPath, const char * remoteFile);   After our remote directories and files have been setup, it is time to perform the file transfers. Normally, this would mean invoking the Copy service for a Subsystem, but two functions have been created to make this process easier:   int twFileManager_GetFile(const char * sourceRepo, const char * sourcePath, const char * sourceFile, const char * targetRepo, const char * targetPath, const char * targetFile, uint32_t timeout, char asynch, char ** tid) int twFileManager_SendFile(const char * sourceRepo, const char * sourcePath, const char * sourceFile, const char * targetRepo, const char * targetPath, const char * targetFile, uint32_t timeout, char asynch, char ** tid)   The table below displays an example of the first set of parameters:   Parameter Example Description sourceRepo SystemRepository The name of FileRepository or RemoteThing to transfer the file FROM. sourcePath outgoing The path specifying the location of the source file. sourceFile The name of the source file.   targetRepo SteamSensor1 The name of FileRepository or RemoteThing to transfer the file TO. targetPath incoming The path specifying the destination location of the file. targetFile incoming.txt The name of the file at the target. This name can differ from the sourceName. timeout 15,000 The amount of time (in seconds) to wait for a synchronous transfer to complete before cancelling the transfer. async false If false, the service call will block for timeout seconds or until the transfer completes. tid incoming0123 The unique TID associated with the file.   The C SDK also provides the ability to create a FileCallback function that the FileManager will call that function when any file transfer events occur. You can provide a wildcard filter so that only file transfer Events of files that match the filter call the callback function. In addition, callbacks can be set up as “one-shots” such that the callback is unregistered automatically after it is invoked the first time.   NOTE: An optional file transfer callback is registered in the code and provided. You will see the output from the function as files are sent and received.   After running this application, you will notice a new file in the transfer/incoming folder after refreshing. This is the file that we created in the ThingWorx Composer file system for the SystemRepository Entity and was able to copy from that location to our local project. We have also sent a file to the server’s SystemRepository. The BrowseFileSystem and GetFileListing services can be used to check for the folders and files created.   twFileManager_RegisterFileCallback(fileCallbackFunc, NULL, FALSE, NULL);     Step 10: Support Other Platforms   All Websocket errors indicate some general issue communicating with the ThingWorx platform. If you experience an issue connecting, refer to the table below for a list of websocket errors, their corresponding codes, and an explanation of the issue.   Code Message Troubleshooting 200 TW_UNKNOWN_WEBSOCKET_ERROR An unknown error occurred on the websocket. 201 TW_ERROR_INITIALIZING_WEBSOCKET An error occurred while initializing the websocket. Check your websocket configuration parameters for validity. 202 TW_TIMEOUT_INITIALIZING_WEBSOCKET A timeout occurred while initializing the websocket. Check the status of the connection to ThingWorx. 203 TW_WEBSOCKET_NOT_CONNECTED The websocket is not connected to ThingWorx. The requested operation cannot be performed. 204 TW_ERROR_PARSING_WEBSOCKET_DATA An error occurred while parsing websocket data. The parser could not break down the data from the websocket. 205 TW_ERROR_READING_FROM_WEBSOCKET An error occurred while reading data from the websocket. Retry the read operation. If necessary, resend the data. 206 TW_WEBSOCKET_FRAME_TOO_LARGE The SDK is attempting to send a websocket frame that is too large. The Maximum Frame Size is set when calling twAPI_Initialize and should always be set to the Message Chunk Size (twcfg.message_chunk_size). 207 TW_INVALID_WEBSOCKET_FRAME_TYPE The type of the frame coming in over the websocket is invalid. 208 TW_WEBSOCKET_MSG_TOO_LARGE The application is attempting to send a message that has been broken up in to chunks that are too large to fit in a frame. You should not see this error. 209 TW_ERROR_WRITING_TO_WEBSOCKET An error occurred while writing to the Web socket. 210 TW_INVALID_ACCEPT_KEY The Accept key sent earlier from ThingWorx is not valid.     Step 11: Next Steps   Congratulations! You've successfully completed the C SDK Tutorial, and learned how to utilize the resources provided in the Edge SDK to create your own application.   Learn More   We recommend the following resources to continue your learning experience:   Capability Link Build Design Your Data Model Build Implement Services, Events, and Subscriptions   Additional Resources   If you have questions, issues, or need additional information, refer to:   Resource Link Community Developer Community Forum Support C Edge SDK Help Center    

  Step 6: Create OPC UA Tag in ThingWorx   We will now create a Device in Kepware with a Tag whose value will be shown in ThingWorx.   Right-click on Channel1 that was just created, then click Next to accept the default name Device1       Click Next six times to accept the default settings, Then click the Select import items button.     Expand the remote OPC UA server URL, then expand OpcPlc and Telemetry.     Click SlowUint1 to select it, then click Add items >>. Click OK, Next, Finish. Return to ThingWorx Composer. Under Browse > Modeling > Industrial Connections, open IndConn_Server. Expand Channel1 > Device1 > OpcPlc, then click Telemetry.     Click the check-box next to SlowUint1. Click Bind to New Entity.     Select RemoteThing, then click OK. Enter azure-opcua-plc in the Name field, then click Save.     Click Properties and Alerts, then Click Refresh to see the property value changing every 10 seconds.     Step 7: Next Steps   Congratulations! You've successfully completed the Connect to an Azure OPC UA Server guide, and learned how to:   Create an OPC UA Server in Azure Configure Kepware as on OPC UA Client Connect Kepware to ThingWorx Foundation Monitor OPC UA data in ThingWorx Composer   Learn More   We recommend the following resources to continue your learning experience: Capability Guide Experience Create Your Application UI   Additional Resources   If you have questions, issues, or need additional information, refer to:   Resource Link Community Developer Community Forum Support Getting Started with ThingWorx Documentation Kepware documentation Support Kepware Support site