GitLab Runner执行Ember生产构建时报错：Cannot read property 'length' of undefined

Hey there, let's break down why your Ember build works locally but fails on GitLab Runner with that frustrating length property error. The key clues here are that the error comes from the broccoli-persistent-filter:TemplateCompiler while processing siemens-addon-help-desk/templates/components/issue-create.hbs, and it only pops up in the production CI environment. Here are the most likely fixes to try:

1. Reset CI Cache & Ensure Fresh Dependencies #

Local builds often rely on cached dependencies or untracked files that aren't present in the GitLab Runner environment. Let's force a clean state for the CI build:

• Add these steps to your GitLab CI configuration to wipe old caches and install dependencies from scratch:

  before_script:
    - rm -rf node_modules dist tmp
    - npm install --no-shrinkwrap
  

• Double-check your .gitignore file to make sure it isn't excluding any template files or related assets that should be committed to Git—missing files in the runner can lead to unexpected undefined values during compilation.

2. Reproduce the Error Locally First #

Your local development build is more forgiving, but the production build runs stricter optimizations and checks. Reproduce the issue locally to simplify debugging:

• Run the exact production build command on your machine:

  ./node_modules/ember-cli/bin/ember build --environment=production
  

• If the error appears locally, inspect issue-create.hbs for:
  • Handlebars {{#each}} blocks iterating over a property that might be undefined (the length error strongly suggests code is trying to check array.length on a non-array value).
  • Custom helpers or dynamic path references that assume a value exists, but aren't properly guarded (e.g., {{someHelper model.missingProperty}} where missingProperty is undefined in production).

3. Lock Down Broccoli Plugin Versions #

Your Ember CLI version (2.16.2) is quite dated, and version mismatches in broccoli plugins between local and CI environments can cause unexpected errors:

• Check the version of broccoli-persistent-filter used in your working local build:

  npm ls broccoli-persistent-filter
  

• Add that exact version to your package.json dependencies to ensure the CI environment uses the same plugin version as your local setup:

  "dependencies": {
    // ... other existing dependencies
    "broccoli-persistent-filter": "X.X.X"
  }
  

4. Audit Environment-Specific Configurations #

Production environment settings might be causing data discrepancies that lead to undefined values in your template:

• Open config/environment.js and review any production-specific overrides. Look for things like:
  • API endpoints that return incomplete data in production
  • Feature flags or settings that disable data loading for production builds
• Ensure that all data required by issue-create.hbs is properly initialized and available in the production environment context.

内容的提问来源于stack exchange，提问作者Ambuk Nag