Travis CI中iOS/tvOS项目构建优化及YML脚本问题咨询

Hey there! Let's tackle your Travis CI build optimization questions step by step—covering Carthage caching, general speed-ups, and checking your .travis.yml for common issues.

Carthage is a major contributor to long build times since it compiles dependencies from scratch by default. Here's how to cache those pre-built frameworks effectively:

Basic Cache Configuration #

Add this block to your .travis.yml to preserve Carthage's build artifacts between runs:

cache:
  directories:
    - Carthage/Build  # Cache pre-compiled iOS/tvOS frameworks
  bundler: true  # Cache Bundler gems if you use them

before_install:
  # Only run Carthage bootstrap if the cached Build folder doesn't exist
  - if [ ! -d "Carthage/Build" ]; then carthage bootstrap --platform iOS,tvOS --cache-builds; fi

Key Details to Remember: #

• Use carthage bootstrap instead of update: Bootstrap installs dependencies exactly as defined in your Cartfile.resolved, which keeps builds stable for CI. update pulls the latest versions, which is unnecessary and slow.
• Add the --cache-builds flag: This tells Carthage to reuse its own local cache, even if Travis's global cache is missed.
• Commit Cartfile.resolved to your repo: Travis automatically invalidates the cache if this file changes (since dependencies would need rebuilding)—this is exactly the behavior you want.

Beyond Carthage caching, here are actionable ways to cut your 18-20 minute build down:

• Use the latest macOS/Xcode image: Older images are slower and have outdated tools. Specify a recent stable image like:

  osx_image: xcode15  # Check Travis's docs for the current stable version
  

• Reduce git clone depth: Only pull the latest commit instead of the entire repo history to save time:

  git:
    depth: 1
  

• Optimize Xcodebuild commands:
  • Skip unnecessary steps like package validation or automatic resolution:

    xcodebuild -scheme "Your-iOS-Scheme" -destination "platform=iOS Simulator,name=iPhone 15" -configuration Release build -disableAutomaticPackageResolution -skipPackagePluginValidation
    

  • Parallelize scheme builds: Split iOS and tvOS builds into separate Travis jobs to run them at the same time:

    jobs:
      include:
        - name: "iOS Build"
          osx_image: xcode15
          script: xcodebuild -scheme "Your-iOS-Scheme" ... build
        - name: "tvOS Build"
          osx_image: xcode15
          script: xcodebuild -scheme "Your-tvOS-Scheme" ... build
    

• Cache DerivedData (carefully): Xcode's DerivedData stores intermediate build files. Caching it can speed up incremental builds, though it may cause occasional conflicts. Add it to your cache to test:

  cache:
    directories:
      - Carthage/Build
      - ~/Library/Developer/Xcode/DerivedData
  

• Skip unnecessary steps: If you don't need to run tests during this build phase, remove test commands. If using Fastlane, use gym with skip_testing: true to skip test runs.
• Leverage Fastlane: Fastlane has built-in CI optimizations. For example, gym automatically handles dependency caching and Xcode build tweaks. A basic setup would replace raw xcodebuild commands with:

  fastlane gym --scheme "Your-iOS-Scheme" --destination "platform=iOS Simulator,name=iPhone 15" --configuration Release
  

Since you're new to CI, here are common pitfalls to watch for in your script:

• Invalid destination flags: Ensure your -destination matches a simulator available in your chosen Xcode image (e.g., "iPhone 15" exists in Xcode 15+, but not older versions).
• Unnecessary sudo: Travis's macOS environment doesn't require sudo for most commands—remove sudo: required if it's present.
• Sequential multi-scheme builds: If you're building iOS and tvOS back-to-back, splitting them into parallel jobs can halve your build time.
• Missing configuration: Without -configuration Release, Xcode builds in Debug mode by default, which is slower and includes extra debug artifacts.
• Redundant dependency installs: If you're running carthage update every time, switch to bootstrap to avoid re-downloading and rebuilding unchanged dependencies.

If you share your actual .travis.yml content, we can spot more specific issues, but these are the most common mistakes to check first.

内容的提问来源于stack exchange，提问作者Abin Baby