Developing Extensions Using Low Code

Data Input of Custom Extensions

The information obtained during extension development mainly consists of three parts: low-code GUI input, pipeline running parameters and other information.

• Low-code GUI input: Obtain the low-code GUI output through environment variables, for example, echo ${Control ID}.
• Pipeline running parameters: Some pipeline running parameters are delivered to environment variables. Currently supported environment variables are listed as follows:

  Variable	Description
  STEP_NAME	Step name of the pipeline.
  STEP_ID	Step ID of the pipeline.
  PLUGIN_VERSION	Version of the extension.
  PIPELINE_ID	Pipeline ID.
  PIPELINE_RUN_ID	Pipeline execution ID.
  PLUGIN_NAME	Extension name.
  PROJECT_ID	Project ID.
  JOB_ID	Task ID of the pipeline.

• Other information is obtained from the interaction with external data through git, wget, and curl.

Data Output of Custom Extensions

Once executed, the custom extension can read file information in a specified path and obtain the metric data output.

1. On the low-code GUI, drag the metrics widget to configure the output threshold of the extension.

   

2. During development, the ${STEP_ID}_result.json and ${STEP_ID}_metrics.json files are exported to the specified path so that metric values can be parsed after the extension is executed.

   Table 1 Output files

   File	Description
   /var/devcloud/workspace/temp-mnt/result/${STEP_ID}_result.json	The output is a text file in {"par1":123, "par2":456} format. After the pipeline is executed, the result is displayed as the corresponding task result. NOTE: Only check extensions can display the result.
   /var/devcloud/workspace/temp-mnt/result/${STEP_ID}_metrics.json	The output is a text file in {"par1":123, "par2":456} format. The metrics control is also used. After the extension is executed, the threshold of the metrics control and the actual file content ${STEP_ID}_metrics.json are parsed and compared for pipeline exit. Precautions: During parsing, empty key values will be ignored. If the corresponding key value cannot be found in the ${STEP_ID}_result.json file, the specified threshold value is used.

   Example: par1 and par2 metrics for exit interception and par3 and par4 for task result display. The sample code is as follows:

   # Optionally, construct the extension output.
   echo '{"par1":100,"par2":200}' > /var/devcloud/workspace/temp-mnt/result/${STEP_ID}_metrics.json
   echo '{"par3":300,"par4":400}' > /var/devcloud/workspace/temp-mnt/result/${STEP_ID}_result.json

3. After the extension is run, click the corresponding step card to view the output.

   

   If a policy is configured for the current extension and applied to the pipeline pass condition, click the pass condition to view the interception.