script

script plugin

This plugin execute a script.

Warn: This plugin will keep running until the execution is done

Runtime(s) must be accessible on the host you deploy µTask if you want to execute interpreted scripts: verify shebang and available packages

Files must be located under scripts folder, you should set exec permissions (+x). Otherwise the script plugin will try to set the exec permissions.

The step will be considered successful if the script returns exit code 0, otherwise, it will be considered as a SERVER_ERROR (and will be retried). For unrecoverable errors (for instance, invalid parameters), it is possible to configure a list of exit codes (see exit_codes_unrecoverable) that should halt the execution (CLIENT_ERROR).

Configuration

Example

An action of type script requires the following kind of configuration:

action:
  type: script
  configuration:
    # mandatory, string
    # file_path field must be related to you scripts path (./scripts)
    # and could modified /w `scripts-path` flag when you run binary
    file_path: hello-world.sh
    # optional, a collection of string
    argv:
        - world
    # optional, string as Duration
    # Valid time units are "ns", "us" (or "µs"), "ms", "s", "m", "h".
    # default is 2m
    timeout: "25s"
    # this is the default mode
    output_mode: manual-lastline
    # optional delimiters to look for an output -- requires output_mode set to manual-delimiters
    #output_manual_delimiters: ["JSON_START", "JSON_END"]
    exit_codes_unrecoverable:
      - "1-10"
      - "100"
      - "110"
    environment:
      FOO: '{{eval `foo`}}'

Note

The plugin returns two objects, output and metadata.

output depends on the output_mode configuration. It is read from the stdout of the script, either on the last line (output_mode set to manual-lastline) or between given delimiters (output_mode set to manual-delimiters, delimiters defined in output_manual_delimiters).

{"dumb_string":"Hello world!","random_object":{"foo":"bar"}}

metadata contains information about the script execution:

{
  "exit_code":"0",
  "process_state":"exit status 0",
  // Output combine Stdout and Stderr streams without any distinction
  "output":"Hello world script\n{\"dumb_string\":\"Hello world!\",\"random_object\":{\"foo\":\"bar\"}}\n",
  "execution_time":"846.889µs",
  "error":""
}

Resources

The script plugin declares automatically resources for its steps:

• fork to rate-limit concurrent execution on the number of forked processes started by the uTask instance
• script:file_path (where file_path is the script path of the plugin configuration) to rate-limit concurrent execution of a specific script