Intermediate everything in DevOps & Cloud, page 29
Code Coverage: What Your Tests Don't Tell You
Code coverage measures which lines of code your tests execute, not how well they're tested. It's used in CI to enforce a testing baseline, but the footgun is mistaking high coverage for high quality—100% coverage can exist with zero useful assertions.
Maven's Build Lifecycle: A Sequence of Build Phases
Maven's build lifecycle is a predefined sequence of phases like compile, test, and package. Running a phase executes all preceding ones, ensuring a consistent build.
Gradle: Code-Based Builds, Not XML
Gradle treats your build process like code, not configuration, using a flexible Groovy or Kotlin DSL instead of rigid XML. It's used for compiling and packaging multi-language projects.
Apache Maven: Convention Over Configuration for Builds
Maven standardizes your build process using a 'convention over configuration' model, defining project structure and dependencies declaratively. It's the backbone of many Java projects, ensuring consistent builds. The footgun is fighting its conventions.
Static Analysis: Read Code, Don't Run It
Static analysis is like a spell checker for your code, catching errors before you run the program. It powers linters and security scanners in CI pipelines to find bugs and vulnerabilities. The footgun: it can't understand intent, leading to false positives.
GitHub Flow: A Simple, Branch-Based Workflow
GitHub Flow is a simple workflow where main is always stable and new work happens on a feature branch. It's used for continuous delivery, from code to documentation.
Git Rebase: Rewriting History for a Cleaner Timeline
Git rebase rewrites history by transplanting your commits onto a new base, creating a clean, linear project history instead of a merge bubble. It's used to catch a feature branch up with main. Never rebase a branch others are using; it rewrites history.
Git Merge: Combining Development Histories
Git merge combines separate lines of development into one branch. It creates a special merge commit that ties the two histories together, preserving the context of each. Use it to integrate a feature branch into your main line.
Pull Requests: A Structured Conversation About Code
A Pull Request (PR) is a structured conversation about a proposed code change. It's used in team projects to review new features and fixes, ensuring quality and sharing knowledge. The footgun is treating PRs as a rubber-stamp approval instead of a real review.
Canary Release: Test New Code on Real Users, Safely
A canary release is like sending a canary into a coal mine: expose a new version to a small group of users to detect problems before a full rollout. It's used to safely test changes in production by gradually shifting traffic.
Blue-Green Deployment: Zero-Downtime Releases
Run two identical production environments, Blue (live) and Green (new). To deploy, just flip a switch routing traffic to Green. This enables zero-downtime releases and instant rollbacks. The footgun is using DNS for the switch, which can lag due to caching.
Infrastructure as Code: Manage Servers with Code, Not Clicks
Infrastructure as Code (IaC) treats servers and networks like software: defined in files and versioned in Git. It's used to automate cloud resource provisioning on AWS or GCP, ensuring consistent, repeatable environments.
Artifact Repository: Your CI/CD's Private Library
An artifact repository is your CI/CD's private library for build outputs like packages and images. CI pipelines publish artifacts here, and deployment scripts pull from it.
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