Add File Commands (#571)

* Add File Commands

* pr updates w/ feedback

* run format

* fix lint/format

* slight update with an example in the docs

* pr feedback

packages/core/src/command.ts

@@ -1,4 +1,5 @@
 import * as os from 'os'
+import {toCommandValue} from './utils'
 
 // For internal use, subject to change.
 
@@ -76,19 +77,6 @@ class Command {
   }
 }
 
-/**
- * Sanitizes an input into a string so it can be passed into issueCommand safely
- * @param input input to sanitize into a string
- */
-export function toCommandValue(input: any): string {
-  if (input === null || input === undefined) {
-    return ''
-  } else if (typeof input === 'string' || input instanceof String) {
-    return input as string
-  }
-  return JSON.stringify(input)
-}
-
 function escapeData(s: any): string {
   return toCommandValue(s)
     .replace(/%/g, '%25')

packages/core/src/core.ts

@@ -1,4 +1,6 @@
-import {issue, issueCommand, toCommandValue} from './command'
+import {issue, issueCommand} from './command'
+import {issueCommand as issueFileCommand} from './file-command'
+import {toCommandValue} from './utils'
 
 import * as os from 'os'
 import * as path from 'path'
@@ -39,7 +41,15 @@ export enum ExitCode {
 export function exportVariable(name: string, val: any): void {
   const convertedVal = toCommandValue(val)
   process.env[name] = convertedVal
-  issueCommand('set-env', {name}, convertedVal)
+
+  const filePath = process.env['GITHUB_ENV'] || ''
+  if (filePath) {
+    const delimiter = '_GitHubActionsFileCommandDelimeter_'
+    const commandValue = `${name}<<${delimiter}${os.EOL}${convertedVal}${os.EOL}${delimiter}`
+    issueFileCommand('ENV', commandValue)
+  } else {
+    issueCommand('set-env', {name}, convertedVal)
+  }
 }
 
 /**
@@ -55,7 +65,12 @@ export function setSecret(secret: string): void {
  * @param inputPath
  */
 export function addPath(inputPath: string): void {
-  issueCommand('add-path', {}, inputPath)
+  const filePath = process.env['GITHUB_PATH'] || ''
+  if (filePath) {
+    issueFileCommand('PATH', inputPath)
+  } else {
+    issueCommand('add-path', {}, inputPath)
+  }
   process.env['PATH'] = `${inputPath}${path.delimiter}${process.env['PATH']}`
 }
 

packages/core/src/file-command.ts

@@ -0,0 +1,24 @@
+// For internal use, subject to change.
+
+// We use any as a valid input type
+/* eslint-disable @typescript-eslint/no-explicit-any */
+
+import * as fs from 'fs'
+import * as os from 'os'
+import {toCommandValue} from './utils'
+
+export function issueCommand(command: string, message: any): void {
+  const filePath = process.env[`GITHUB_${command}`]
+  if (!filePath) {
+    throw new Error(
+      `Unable to find environment variable for file command ${command}`
+    )
+  }
+  if (!fs.existsSync(filePath)) {
+    throw new Error(`Missing file at path: ${filePath}`)
+  }
+
+  fs.appendFileSync(filePath, `${toCommandValue(message)}${os.EOL}`, {
+    encoding: 'utf8'
+  })
+}

packages/core/src/utils.ts

@@ -0,0 +1,15 @@
+// We use any as a valid input type
+/* eslint-disable @typescript-eslint/no-explicit-any */
+
+/**
+ * Sanitizes an input into a string so it can be passed into issueCommand safely
+ * @param input input to sanitize into a string
+ */
+export function toCommandValue(input: any): string {
+  if (input === null || input === undefined) {
+    return ''
+  } else if (typeof input === 'string' || input instanceof String) {
+    return input as string
+  }
+  return JSON.stringify(input)
+}