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jsonify permalink

convert object to json string permalink

Use jsonify to serialize a pypyr context object to a json string.

- name: pypyr.steps.set
  in:
    set:
        myJsonDict: !jsonify
            k1: v1
            k2: 123
            k3: False
            k4:
            - 1
            - 2
            - a: b
                c: d
        myJsonList: !jsonify
            - zero
            - one
            - two
        myJsonNull: !jsonify null
        myJsonNumber: !jsonify 99
        myJsonQuotedString: !jsonify "0123"
        myJsonBareString: !jsonify arbitrary string
- name: pypyr.steps.echo
  in:
    echoMe: |
        myJsonDict: {myJsonDict}
        myJsonList: {myJsonList}
        myJsonNull: {myJsonNull}
        myJsonNumber: {myJsonNumber}
        myJsonQuotedString: {myJsonQuotedString}
        myJsonBareString: {myJsonBareString}

This gives output:

myJsonDict: {"k1": "v1", "k2": 123, "k3": false, "k4": [1, 2, {"a": "b", "c": "d"}]}
myJsonList: ["zero", "one", "two"]
myJsonNull: null
myJsonNumber: 99
myJsonQuotedString: "0123"
myJsonBareString: "arbitrary string"

You could think of this as converting yaml to json, however, in actuality under the hood pypyr will serialize any given object in context to json with jsonify so it’s not necessarily just yaml as the input. It just so happens that yaml from pipeline is the likeliest input, but jsonify will work equally well if you manipulate context directly via the api.

use with substitutions permalink

A jsonify structure can contain pypyr formatting expressions for substitutions, including py strings for inline python and sic strings to avoid processing curly braces.

- name: pypyr.steps.set
  comment: combine jsonify with other formatting expressions
  in:
    a_string: hello there
    replace_me: 123
    
    set:
      arb_payload: !jsonify
        k1: value {a_string}
        k2: !py hex(255)
        k3: !sic a string with {literal} curly braces
        k4: '{replace_me}'
        k5: False

- name: pypyr.steps.cmd
  comment: post the json payload string to a web-server via curl
  in:
    cmd: |
      curl -H 'Content-Type: application/json' -d '{arb_payload}' -X POST 'https://httpbin.org/post'

The json payload posted to the web-server looks like this:

{
  "k1": "value hello there",
  "k2": "0xff",
  "k3": "a string with {literal} curly braces",
  "k4": 123,
  "k5": false
}

use with flat format permalink

If you want to assign a jsonified string to another context key using a single replacement token expression, use the ff flat format directive to prevent pypyr from interpreting the json string’s {curly braces} as pypyr formatting expressions:

- name: pypyr.steps.set
  comment: combine jsonify with other formatting expressions
  in:
    a_string: hello there
    replace_me: 123
    
    set:
      arb_payload: !jsonify
        k1: value {a_string}
        k2: !py hex(255)
        k3: !sic a string with {literal} curly braces
        k4: '{replace_me}'
        k5: False
    
- name: pypyr.steps.echo
  comment: arb_payload contains a string with json curly braces
           since pypyr recurses single token expressions by default,
           use Flat Format (ff).
  in:
    echoMe: '{arb_payload:ff}'

see also

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