Read YAML Github action

This action reads a .yaml file, and sets one output for every key it has. These outputs can be used in later steps, which allows a yaml file to function as a configuration file within a Github workflow.

Furthermore it supports variables interpolation, using the $(var) syntax. This allows for complex dependencies and relationship between keys, enabling great flexibility when creating the yaml file.

It supports hierarchy of nested values, representing the output through dot notation.

It also supports filtering dot notations keys in the output so that a specific keys dynamically can be selected in the github workflow.

Finally, it supports adding dot notations keys delimited with _ as environment variables.

For more information, check the example below.

Configuration keys

There are 1 mandatody configuration as 'config' and two optional configurations as 'env-var-prefx' and 'key-path-pattern'

config

This configuration is mandatory and is the path to the yaml file that action should use as its source configuration.

env-var-prefix

This configuration is optional and is a prefix to the environment variables generated by the action.

for example if the dot notation key in th eoutput will be like a.b.c.d.x and the value for this config is myVars then the environment variable set by the action will be like myVars_a_b_c_d_x .

By omitting this config the action will not generate any environment variable.

key-path-pattern

This configuration is optional and is a regular expression that filters out keys that matches with the pattern.

It also remove that pattern from the key string, so if the dot notation key is like a.b.c.d.x and the key-path-pattern is ^a\.b\. the output key will be c.d.x .

By omitting this config the action will not do any filteration and key string replacement.

Example usage

Four examples are provided in the examples folder.

Basic config

The config file contains the following keys:

namespace: namespace_example
location: location_example
environment: dev

resource_group_name: $(namespace)-$(location)-$(environment) # this will be replaced with the variables above

Note that the key resource_group_name uses variable interpolation. The key value will resolve to: namespace_example-location_example-dev.

The action reads the yaml file as following:

name: helpers-read-yaml

on:
  push:
  workflow_dispatch:

jobs:
  read-yaml:
    runs-on: ubuntu-latest
    steps:
      - name: checkout
        uses: actions/checkout@v3

      - name: read-yaml-file
        uses: pietrobolcato/action-read-yaml@1.0.0
        id: read_action_js
        with:
          config: ${{ github.workspace }}/examples/config_example.yaml

      - name: use-yaml-file
        run: |
          echo namespace: ${{ steps.read_action_js.outputs['namespace'] }}
          echo location: ${{ steps.read_action_js.outputs['location'] }}
          echo environment: ${{ steps.read_action_js.outputs['environment'] }}
          echo resource_group_name: ${{ steps.read_action_js.outputs['resource_group_name'] }}

And outputs:

namespace: namespace_example
location: location_example
environment: dev
resource_group_name: namespace_example-location_example-dev

Nested config

The config file contains the following keys:

name: example
environment:
  name: example
  permissions:
    - name: example
      permission: read
    - name: example2
      permission: write
deployment:
  code:
    source:
      libs: path/to/libs
      entry: path/to/entry

Note that this is contained nested values. The action reads the yaml file in the same way as the example above, and outputs:

name: example
environment.name: example
environment.permissions.0.name: example
environment.permissions.0.permission: read
environment.permissions.1.name: example2
environment.permissions.1.permission: write
deployment.code.source.libs: path/to/libs
deployment.code.source.entry: path/to/entry

Environment variable output and filter pattern

The config file contains the following keys:

name: example
environment:
  name: example
  permissions:
    - name: example
      permission: read
    - name: example2
      permission: write
deployment:
  code:
    source:
      libs: path/to/libs
      entry: path/to/entry

The action reads the yaml file as following:

name: helpers-read-yaml

on:
  push:
  workflow_dispatch:

jobs:
  read-yaml:
    runs-on: ubuntu-latest
    steps:
      - name: checkout
        uses: actions/checkout@v3

      - name: read-yaml-file-1
        uses: ehsandanesh/action-read-yaml@env-var-and-filter
        id: deployments
        with:
          config: ${{ github.workspace }}/examples/filter/config_example.yaml
          # This key is optional, omitting that will cause the action to skip environment variables output generation
          # This key will be the prefix for the environment variables generated by this action
          env-var-prefix: myEnv
          # This RegEx is the pattern that will filter out the dot notation keys and also the pattern itself will be removed from the key name
          key-path-pattern: ^deployment\.code\.

      - name: use-yaml-file-1
        run: |
          echo deployment source libs: ${{ steps.deployments.outputs['source.libs'] }}
          echo deployment source entry: ${{ steps.deployments.outputs['source.entry'] }}
          echo
          env | grep "myEnv_"
          echo
          echo deployment source libs: $myEnv_source_libs
          echo deployment source entry: $myEnv_source_entry

      - name: read-yaml-file-2
        uses: ehsandanesh/action-read-yaml@env-var-and-filter
        id: permissions
        with:
          config: ${{ github.workspace }}/examples/filter/config_example.yaml
          env-var-prefix: myEnv
          key-path-pattern: ^environment\.permissions\.

      - name: use-yaml-file-2
        run: |
          echo first permission name: ${{ steps.permissions.outputs['0.name'] }}
          echo first permission permissions: ${{ steps.permissions.outputs['0.permission'] }}
          echo second permission name: ${{ steps.permissions.outputs['1.name'] }}
          echo second permission permissions: ${{ steps.permissions.outputs['1.permission'] }}
          echo
          env | grep "myEnv_"
          echo
          for i in 0 1
          do
            name="myEnv_${i}_name"
            permission="myEnv_${i}_permission"
            echo first permission name: $(eval "echo \${$name}")
            echo first permission permissions: $(eval "echo \${$permission}")

          done

use-yaml-file-1 outputs:

deployment source libs: path/to/libs
deployment source entry: path/to/entry

myEnv_source_entry=path/to/entry
myEnv_source_libs=path/to/libs

deployment source libs: path/to/libs
deployment source entry: path/to/entry

use-yaml-file-2 outputs:

first permission name: example
first permission permissions: read
second permission name: example2
second permission permissions: write

myEnv_0_name=example
myEnv_source_entry=path/to/entry
myEnv_source_libs=path/to/libs
myEnv_1_permission=write
myEnv_1_name=example2
myEnv_0_permission=read

first permission name: example
first permission permissions: read
first permission name: example2
first permission permissions: write