fix: Add read-file action (#107)

.github/workflows/example-read-file.yaml

@@ -0,0 +1,27 @@
+name: '📗 Example Set Output'
+
+on:
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+jobs:
+  run-example:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Read a File
+        id: read-file
+        uses: ./public/read-file
+        with:
+          path: 'README.md'
+
+      - name: Summary
+        uses: streetsidesoftware/actions/public/summary@v1
+        with:
+          text: |
+            # Summary
+            File:
+            ```````````markdown
+            ${{ steps.read-file.outputs.result }}
+            ```````````

public/read-file/README.md

@@ -0,0 +1,7 @@
+## `read-file` Action
+
+Read a file from the filesystem and return it in `output.result`.
+
+Example:
+
+<!--- @@inject: ../../.github/workflows/example-read-file.yaml --->

public/read-file/action.yaml

@@ -0,0 +1,24 @@
+name: read-file
+description: Read a file and return the contents.
+
+inputs:
+  path:
+    description: The path to the file to read.
+    required: true
+outputs:
+  result:
+    description: The contents of the file.
+    value: ${{ steps.read-file.outputs.result }}
+runs:
+  using: composite
+  steps:
+    - name: Read File
+      id: read-file
+      uses: actions/github-script@v3
+      env:
+        INPUT_PATH: ${{ inputs.path }}
+      with:
+        result-encoding: string
+        script: |
+          const fs = require('fs');
+          return fs.readFileSync(process.env.GITHUB_WORKSPACE + '/' + process.env.INPUT_PATH, 'utf8') };