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13-advanced-jenkinsfile.md

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+# Building Continuous Delivery (CD) Pipelines
+
+## Enhancing a pipeline with advanced features
+
+We'll want to enhance the pipeline by additional stages and implement a release workflow. The project is going to use an external tool called GoReleaser to publish cross-compiled artifacts to GitHub Releases. The binaries should only be released if the commit has been tagged.
+
+1. Add stage named `Test` that executes the Go `test` command.
+    * Add a build step that runs the shell command `go test ./...`.
+    * Generate code coverage metrics by adding the option `-coverprofile=coverage.txt` to the build step.
+    * Publish the code coverage metrics to CodeCov by sending a curl command `curl -s https://codecov.io/bash | bash -s -`.
+    * Create an account on CodeCov, determine the CodeCov token (aka Repository Upload Token) and set it up as credential in Jenkins.
+    * Retrieve the credential and set the value as environment variable named `CODECOV_TOKEN`.
+2. Add a stage named `Code Analysis` that uses [golangci-lint](https://github.com/golangci/golangci-lint) to detect issues with the code.
+    * Add a build step for installing the `golangci-lint` with the shell command `curl -sfL https://install.goreleaser.com/github.com/golangci/golangci-lint.sh | bash -s -- -b $GOPATH/bin v1.17.1`
+    * Add a build step that runs `golangci-lint` with the shell command `golangci-lint run`.
+3. Add a stage named `Release` that uses [GoReleaser](https://github.com/goreleaser/goreleaser).
+    * Only build this step if the commit has been tagged.
+    * Set up a credential in Jenkins named `github_token` and set your GitHub token. 
+    * Retrieve the credential and set the value as environment variable named `GITHUB_TOKEN`.
+    * Add a build step that runs the shell command `curl -sL https://git.io/goreleaser | bash`.
+
+<details><summary>Show Solution</summary>
+<p>
+
+Create the CodeCov credentials.
+
+![CodeCov Credentials](./images/13-advanced-jenkinsfile/codecov_token_credentials.png)
+
+You can implement the "Test" stage as follows.
+
+```groovy
+stage('Test') {
+    environment {
+        CODECOV_TOKEN = credentials('codecov_token')
+    }
+    steps {
+        sh 'go test ./... -coverprofile=coverage.txt'
+        sh "curl -s https://codecov.io/bash | bash -s -"
+    }
+}
+```
+
+You can implement the "Code Analysis" stage as follows.
+
+```groovy
+stage('Code Analysis') {
+    steps {
+        sh 'curl -sfL https://install.goreleaser.com/github.com/golangci/golangci-lint.sh | bash -s -- -b $GOPATH/bin v1.17.1'
+        sh 'golangci-lint run'
+    }
+}
+```
+
+Create the CodeCov credentials.
+
+![GitHub Credentials](./images/13-advanced-jenkinsfile/github_token_credentials.png)
+
+You can implement the "Release" stage as follows.
+
+```groovy
+stage('Release') {
+    when {
+        buildingTag()
+    }
+    environment {
+        GITHUB_TOKEN = credentials('github_token')
+    }
+    steps {
+        sh 'curl -sL https://git.io/goreleaser | bash'
+    }
+}
+```
+
+</p>
+</details>