You can use the data forwarding feature of the rules engine to forward device data to an MNS topic. Your business server subscribes to the messages of the topic. This implements high-performance message transmission between your business server and devices.This article describes the data forwarding process. In this example, a Thing Specification Language (TSL) communication topic is used as the source topic.
- A data source named DataSource is created and a TSL communication topic is added the data source. For more information, see Create a data source.
- An MNS topic is created. A subscription whose Push Type parameter is set to HTTP or
Queue is created for the topic. For more information, see the MNS documentation.
Notice If you use an IoT Platform instance of the Enterprise Edition, the region where the MNS topic resides must be the same as that of the IoT Platform instance.
Create a data destination
- Log on to the IoT Platform console.
- On the Overview page, find the instance and click the instance name to go to the Instance Details page. Notice Enterprise Edition instances are available only in the Japan (Tokyo) region. If your IoT Platform is not activated in the Japan (Tokyo) region, skip this step.
- In the left-side navigation pane, choose .
- Optional:On the Data Forwarding page, click Go to New Version in the upper-right corner to go to the new version. Note If you have performed this step, the Data Forwarding page of the new version appears after you choose Rules > Data Forwarding.
- Click the Data Destination tab. On this tab, click Create Data Destination.
- In the Create Data Destination dialog box, enter a data destination name. In this example, enter DataPurpose. Set the parameters and then click OK.
Parameter Description Operation Select Send Data to MNS. Region Select a region where MNS runs. Topic Select an MNS topic that is used to receive data.
MNS sends received messages to a subscription of the topic. The Push Type parameter value of the subscription is HTTP or Queue. You can subscribe to messages that IoT Platform pushes to MNS through only the HTTP or queue method.
To create an MNS topic and subscription in the MNS console, click Create Topic. For more information, see the MNS documentation.
Role Authorize IoT Platform to write data to MNS.
If you have not created a Resource Access Management (RAM) role, click Create RAM Role to go to the RAM console, create a RAM role, and then grant permissions. For more information, see Create a RAM role.
Configure and start a parser
- Create a parser named DataParser. For more information, see Create a parser.
- On the Parser Details page, associate the parser with the created data source.
- In the Data Source step of the wizard, click Associate Data Source.
- In the dialog box that appears, select DataSource from the Data Source drop-down list, and then click OK.
- On the Parser Details page, associate the parser with the created data destination.
- Click Data Destination in the wizard. In the Data Destination section, click Associate Data Destination.
- In the dialog box that appears, select DataPurpose from the Data Destination drop-down list, and then click OK.
- In the Data Destination section, view and save the data destination ID. In this example, the ID is 1000. When you write the parser script, you must use the data destination ID.
- On the Parser Details page, click Parser.
- In the code editor, enter a script. For more information about how to write a script,
see Sample script.For more information about the function parameters, see Functions.
// Use the payload() function to obtain the data that is submitted by devices and convert the data by using the JSON format. var data = payload("json"); // Forward submitted TSL data. writeMns(1000, data)
- Click Debugging. In the dialog box that appears, select a product and a device, specify a topic,
and enter payload data to verify whether the script can run properly.The following figure shows the parameters.
The following result indicates that the script is implemented.
- Click Publish.
- Go to the Parser tab of the Data Forwarding page. Find the DataParser parser and click Start in the Actions column to start the parser.