Support using a file

action.yml

@@ -7,7 +7,8 @@ branding:
 inputs:
   script:
     description: The script to run
-    required: true
+  file:
+    description: The javascript file to run
   github-token:
     description: The GitHub token used to create an authenticated client
     default: ${{ github.token }}

src/main.ts

@@ -1,6 +1,7 @@
 import * as core from '@actions/core'
 import {context, GitHub} from '@actions/github'
 import {callAsyncFunction} from './async-function'
+import { existsSync, readFileSync } from 'fs'
 
 process.on('unhandledRejection', handleError)
 main().catch(handleError)
@@ -15,8 +16,8 @@ async function main() {
   if (userAgent != null) opts.userAgent = userAgent
   if (previews != null) opts.previews = previews.split(',')
   const github = new GitHub(token, opts)
-  const script = core.getInput('script', {required: true})
-
+  const script = loadScript()
+  
   // Using property/value shorthand on `require` (e.g. `{require}`) causes compilatin errors.
   const result = await callAsyncFunction(
     {require: require, github, context, core},
@@ -42,6 +43,25 @@ async function main() {
   core.setOutput('result', output)
 }
 
+function loadScript(){
+  const file = core.getInput('file')
+  let script = core.getInput('script')
+
+  if(!script && !file){
+    throw new Error('either "script" or "file" must be a "string')
+  }
+
+  if(file){
+    if(!existsSync(file)){
+      throw new Error('file can\'t be found: ' + file)
+    }
+
+    script = readFileSync(file, 'utf-8')
+  }
+
+  return script
+}
+
 function handleError(err: any) {
   console.error(err)