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jsongithub-actions

Loop through JSON data and run the job for each set of inputs

I have an input.json file that looks like below

{
  "appname": "apple",
  "category": "fruit",
  "buildapp": [
    {
      "workdir": "work1",
      "tesdir": "test1",
      "setdata": {
        "set1": "value1",
        "set2": "value2"
      }
     },
     {
      "workdir": "work2",
      "tesdir": "test2",
      "setdata": {
        "set1": "value3",
        "set2": "value4"
      }
   }
  ]
}

I have to read it in GitHub Actions and loop through each buildapp section and print all the "key" and corresponding "value" pair.

Solution

  • You can use the matrix strategy to define inputs for your publishing step.

    In this case, the workflow can be divided into two separate jobs: the first job should provide the output with a tags array and the second job should use this output as a matrix input:

    name: 'Loop JSON'

on:
  workflow_dispatch:

jobs:
  read-json:
    runs-on: ubuntu-latest
    outputs:
      json-content: ${{ steps.file.outputs.content }}
    steps:
      - uses: actions/checkout@v4

      - name: Read the file
        id: file
        uses: juliangruber/read-file-action@v1
        with:
          path: ./file.json

  loop-json:
    runs-on: ubuntu-latest
    needs: read-json
    strategy:
      matrix:
        app: ${{ fromJSON(needs.read-json.outputs.json-content).buildapp }}
    steps:
      - run: echo ${{ matrix.app.workdir }}

    Resulting workflow:

    enter image description here

    In this example, I used the Read file Action to read the json file from my repository.

    Each job will print the value of the workdir node. Following this example, you can access the other values.

    The file:

    {
  "appname" : "apple",
  "category" : "fruit",
  "buildapp": [
    {
      "workdir": "work1",
      "tesdir" : "test1",
      "setdata" : {
        "set1": "value1",
        "set2": "value2"
      }
    },
    {
      "workdir": "work2",
      "tesdir" : "test2",
      "setdata" : {
        "set1": "value3",
        "set2": "value4"
      }
    }
  ]
}

    Similar cases with the matrix usage: