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You can access data passed at runtime by adding a params field to your
workflow, which names the argument the workflow uses to store the data you
pass in. If passing in a JSON object, you can then use dot notation to access
the arguments. For example:
YAML
main: params: [ARG_NAME] steps: - step1: return: ${ARG_NAME.PARAM_NAME}
JSON
{ "main": { "params": ["ARG_NAME",] "steps": [ { "step1": { "return": "${ARG_NAME.PARAM_NAME}" } } ] } }
Note the following:
For a workflow to receive runtime arguments there must be a
mainblock.The
mainblock accepts a single argument that is the name of any valid JSON data type: an array, an object, or a string.As a best practice, passing in an object with multiple, named arguments makes it easier to understand their purpose, and to add arguments. You can also then use dot notation to access the arguments.
Other subworkflows can have multiple arguments.
The following workflow returns a "Hello" greeting to a person whose first and
last name you pass as a string in JSON format to the workflow in an execution
request. For example, if you pass in the argument
{"firstName":"Workflows","lastName":"User"}, the results of the
execution should include the output "Hello, Workflows User".
YAML
main: params: [person] steps: - step1: assign: - outputVar: ${"Hello, " + person.firstName + " " + person.lastName} - step2: return: ${outputVar}
JSON
{ "main": { "params": [ "person" ], "steps": [ { "step1": { "assign": [ { "outputVar": "${"Hello " + person.firstName + " " + person.lastName}" } ] } }, { "step2": { "return": "${outputVar}" } } ] } }
For more information about using runtime arguments, see Pass runtime arguments in an execution request.