Examples: Parsing a Streamed Response

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Scenario: You receive streamed (SSE-style) responses from an action and want to parse it into objects.

An HTTP action returns a streamed response in this format:

data: {"thread_id": "d7b653f6-076a-4dfe-ae1f-cba4c442jd34", "date": "2025-11-11T20:37:49.053856Z"}

data: {"chunk": "echo bravo papa juliet oscar echo kilo mike kilo. (topic: hello from azure)"}

data: {"chunk": "charlie delta lima victor zulu whiskey delta uniform november. (topic: hello from azure)"}

data: {"chunk": "victor tango foxtrot india hotel tango papa xray alpha romeo. (topic: hello from azure)"}

data: {"chunk": "lima hotel oscar november uniform whiskey zulu india whiskey papa. (topic: hello from azure)"}

You want to produce:

• thread_id from the first object
• date from the first object
• textas a concatenation of all chunk values

Approach

Treat the streamed output as a JSON array encoded as text:

1. Remove the data: prefix
2. Create JSON Strings
3. Parse with $PARSE_JSON()
4. Extract metadata from index [0] and chunks from [1:]

In your compound action the return can reference the SSE action

- return:
    output_mapper:
      thread_id: $CONCAT("[", data.action_output.$REPLACE("data: ", ",").$TRIM(),"]"], "").$PARSE_JSON([0].thread_id
      date: $CONCAT(["[", data.action_output.$REPLACE("data: ", ",").$TRIM(),"]"], "").$PARSE_JSON()[0].date
      text:
        EVAL():
          expression: $CONCAT(x, " ")
          args:
            x:
              MAP():
                items: >
                  $CONCAT(
                    ["[", data.action_output.$REPLACE("data: ", ",").$TRIM()[1:], "]"],
                    ""
                  ).$PARSE_JSON()[1:]
                converter: item.chunk

Or

MERGE():
  - data.action_output.$SPLIT("\n\n")[0].$REPLACE("^data: ", "").$PARSE_JSON()
  - text: data.action_output.$TRIM().$SPLIT("\n\n").$MAP(x => x.$REPLACE("^data: ", "").$PARSE_JSON().chunk).$CONCAT("\n", true)