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Scripting

Inline scripting involves embedding and executing code directly within Godspeed YAML code (e.g. workflows, datasources, eventsource, events, etc.,) enhancing seamless integration of script-based logic or functionality.
It is used directly by embedding the code/variables in <% %> tags. This code is evaluated whenever the yaml is needed to be evaluated e.g. at loadtime or runtime.

Loadtime evaluation There are some variables/code which should be evaluated at loadtime. For example, using configs and mappings in datasources, events, or eventsources as given below:

type: axios
base_url: <% config.api.base_url %>
"http.post./helloworld":
  fn: helloworld
  body:
    content:
      application/json:
        schema:
          type: object
          properties:
            name:
              type: string
            gender:
              type: string
              enum: <% mappings.gender %>

Runtime evaluation There are some variables/code which should be evaluated at runtime. For example, using GSContext properties in workflows as given below:

id: helloworld
tasks:
  - id: first_task
    fn: com.gs.return
    args: <% "Hello, The gender of " + inputs.body.name + " is " + inputs.body.gender %>

Default language at global level​

The default language is js. You can change the default language globally in defaults.lang key in config/default.yaml. It will be applicable everywhere unless overridden explicitly.

defaults:
  lang: js #coffee

Override the default language​

You can override the default language by specifying the language inside the starting tag like <coffee% or <js%

type: axios
base_url: <js% config.api.base_url %>
port: <coffee% config.port %>

Scripting in datasources​

Within datasources, config or mappings, can be accessed at loadtime.

type: axios
base_url: <% config.api.base_url %>

Scripting in eventsources and events​

Within datasources, you can use scripting as given in the below examples:

type: express
port: <% config.http.port %>
docs:
  endpoint: /api-docs
jwt:
  issuer: <% config.jwt.iss %>
  audience: <% config.jwt.aud %>
  secretOrKey: <%  config.jwt.sec %>
authz:
  - fn: com.gs.transform 
    id: authz_task
    args: | # if this condition fails, the else gets executed
      <js% 
        if (inputs.user.role !== 'admin') { 
            return {
            success: false, 
            code: 403,
            message: "Authorization failed"
          }
        }
      %>  
"http.post./helloworld":
  fn: helloworld
  body:
    content:
      application/json:
        schema:
          type: object
          properties:
            name:
              type: string
            gender:
              type: string
              enum: <% mappings.gender %>
  authz:
    - fn: com.gs.transform 
      id: authz_task
      args: | # if this condition fails, the else gets executed
        <js% 
          if (inputs.user.role !== 'system admin') { 
              return {
              success: false, 
              code: 403,
              message: "Authorization failed"
            }
          }
        %>