feat: Allow specifying inputs as environment variables (#214)

Author: ytausch

.github/workflows/test.yml

@@ -943,6 +943,54 @@ jobs:
             py311 py312
           activate-environment: py311
 
+  env-variable-input-custom-bin-path:
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+    runs-on: ${{ matrix.os }}
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      - name: Move pixi.toml
+        run: mv test/default/* .
+      - uses: ./
+        env:
+          SETUP_PIXI_PIXI_BIN_PATH: custom-bin/pixi${{ matrix.os == 'windows-latest' && '.exe' || '' }}
+        with:
+          cache: false
+      - run: |
+          test -f custom-bin/pixi${{ matrix.os == 'windows-latest' && '.exe' || '' }}
+          pixi --help
+          which pixi | grep -q custom-bin/pixi
+          # which pixi should be absolute
+          which pixi | grep -q "^/"
+
+  env-variable-input-custom-pixi-url:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      - name: Move pixi.toml
+        run: mv test/old-pixi-lockfiles/* .
+      - uses: ./
+        env:
+          SETUP_PIXI_PIXI_URL: https://github.com/prefix-dev/pixi/releases/download/v0.14.0/pixi-x86_64-unknown-linux-musl
+        with:
+          cache: false
+      - run: pixi --version | grep -q "pixi 0.14.0"
+
+  env-variable-input-precendence:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      - name: Move pixi.toml
+        run: mv test/old-pixi-lockfiles/* .
+      - uses: ./
+        env:
+          SETUP_PIXI_PIXI_URL: https://github.com/prefix-dev/pixi/releases/download/v0.14.0/pixi-x86_64-unknown-linux-musl
+        with:
+          cache: false
+          pixi-url: https://github.com/prefix-dev/pixi/releases/download/v0.49.0/pixi-x86_64-unknown-linux-musl
+      - run: pixi --version | grep -q "pixi 0.49.0"
+
   test-cache-fail-no-lockfile:
     runs-on: ${{ matrix.os }}
     strategy:

README.md

@@ -405,6 +405,17 @@ Optionally, you can combine this with the `pixi-url-bearer-token` input argument
     pixi-url-bearer-token: ${{ secrets.PIXI_MIRROR_BEARER_TOKEN }}
 ```
 
+### Setting inputs from environment variables
+
+Alternatively to setting the inputs in the `with` section, you can also set each of them using environment variables.
+The corresponding environment variable names are derived from the input names by converting them to uppercase, replacing hyphens with underscores, and prefixing them with `SETUP_PIXI_`.
+
+For example, the `pixi-bin-path` input can be set using the `SETUP_PIXI_PIXI_BIN_PATH` environment variable.
+
+This is particularly useful if executing the action on a self-hosted runner.
+
+Inputs always take precedence over environment variables.
+
 ## More examples
 
 If you want to see more examples, you can take a look at the [GitHub Workflows of this repository](.github/workflows/test.yml).

dist/index.js

@@ -94,10 +94,30 @@ export const PATHS = {
   pixiBin: path.join(os.homedir(), '.pixi', 'bin', `pixi${os.platform() === 'win32' ? '.exe' : ''}`)
 }
 
+const getEnvironmentVariableName = (key: string): string => {
+  return `SETUP_PIXI_${key.toUpperCase().replace(/-/g, '_')}`
+}
+
+const inputOrEnvironmentVariable = (key: string): string | undefined => {
+  const inputValue = core.getInput(key)
+  // GitHub actions sets empty inputs to the empty string
+  if (inputValue !== '') {
+    return inputValue
+  }
+
+  const envVarName = getEnvironmentVariableName(key)
+  const envVarValue = process.env[envVarName]
+  // Empty environment variables are treated as undefined
+  if (envVarValue !== undefined && envVarValue !== '') {
+    core.debug(`Using environment variable ${envVarName} with value: ${envVarValue}`)
+    return envVarValue
+  }
+  return undefined
+}
+
 const parseOrUndefined = <T>(key: string, schema: z.ZodSchema<T>, errorMessage?: string): T | undefined => {
-  const input = core.getInput(key)
-  // GitHub actions sets empty inputs to the empty string, but we want undefined
-  if (input === '') {
+  const input = inputOrEnvironmentVariable(key)
+  if (input === undefined) {
     return undefined
   }
   const maybeResult = schema.safeParse(input)
@@ -111,18 +131,16 @@ const parseOrUndefined = <T>(key: string, schema: z.ZodSchema<T>, errorMessage?:
 }
 
 const parseOrUndefinedJSON = <T>(key: string, schema: z.ZodSchema<T>): T | undefined => {
-  const input = core.getInput(key)
-  // GitHub actions sets empty inputs to the empty string, but we want undefined
-  if (input === '') {
+  const input = inputOrEnvironmentVariable(key)
+  if (input === undefined) {
     return undefined
   }
   return schema.parse(JSON.parse(input))
 }
 
 const parseOrUndefinedList = <T>(key: string, schema: z.ZodSchema<T>): T[] | undefined => {
-  const input = core.getInput(key)
-  // GitHub actions sets empty inputs to the empty string, but we want undefined
-  if (input === '') {
+  const input = inputOrEnvironmentVariable(key)
+  if (input === undefined) {
     return undefined
   }
   return input