added generate-release-notes-from-changelog task

Author: patrickcrocker

README.md

@@ -5,13 +5,13 @@ Common Concourse Pipeline Tasks
 
 All examples use the following resources:
 
-```
+```yaml
 resource_types:
 - name: cf-cli-resource
   type: docker-image
   source:
-    repository: patrickcrocker/cf-cli-resource
-    tag: 2.0.0
+    repository: pivotalpa/cf-cli-resource
+    tag: latest
 
 resources:
 - name: pipeline-tasks
@@ -33,7 +33,7 @@ resources:
 
 ## Generate a Cloud Foundry Manifest
 
-```
+```yaml
 - name: test
   plan:
   - aggregate:
@@ -57,3 +57,42 @@ resources:
       path: artifact/myapp-*.jar
       current_app_name: {{cf-test-app-name}}
 ```
+
+## Generate release information
+
+This example showcases tasks commonly used with [github-release](https://github.com/concourse/github-release-resource):
+* `generate-github-release`: Generates a version string (ex: v1.0.0) for the `release-name` and `release-tag` files.
+* `generate-commitish`: Generates the [commitish](https://stackoverflow.com/questions/23303549/what-are-commit-ish-and-tree-ish-in-git) file.
+* `generate-release-notes`: Generates the release notes for a particular version by parsing a change log format based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/) and [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
+
+```yaml
+- name: shipit
+  serial_groups: [version]
+  plan:
+  - aggregate:
+    - get: pipeline-tasks
+    - get: project
+      passed: [build]
+    - get: version
+      passed: [build]
+      params: {bump: final}
+  - task: generate-github-release
+    file: pipeline-tasks/generate-github-release/task.yml
+    output_mapping: {task-output: generate-github-release-output}
+  - task: generate-commitish
+    file: pipeline-tasks/generate-commitish/task.yml
+    output_mapping: {task-output: generate-commitish-output}
+  - task: generate-release-notes
+    file: pipeline-tasks/generate-release-notes-from-changelog/task.yml
+    input-mapping: {task-input: project}
+    output-mapping: {task-output: generate-release-notes-output}
+  - put: github-release
+    params:
+      name: generate-github-release-output/release-name
+      tag: generate-github-release-output/release-tag
+      commitish: generate-commitish-output/commitish
+      body: generate-release-notes-output/RELEASE_NOTES.md
+  - put: version
+    params: {file: version/version}
+
+```

generate-release-notes-from-changelog/task.sh

@@ -0,0 +1,49 @@
+#!/bin/bash
+
+set -eu
+set -o pipefail
+
+[ 'true' = "${DEBUG:-}" ] && set -x
+
+: "${CHANGELOG_FILE:?not set or empty}"
+: "${VERSION_FILE:?not set or empty}"
+: "${RELEASE_NOTES_FILE:?not set or empty}"
+
+function error_and_exit() {
+  local message=${1:-<no message set>}
+  echo "ERROR: $message" >&2
+  exit 1
+}
+
+[ ! -f "version/$VERSION_FILE" ] && error_and_exit "version file does not exist: version/$VERSION_FILE"
+version=$(cat "version/$VERSION_FILE")
+
+[ ! -f "task-input/$CHANGELOG_FILE" ] && error_and_exit "changelog file does not exist: task-input/$CHANGELOG_FILE"
+capture=false
+content=
+while read line; do
+
+  # Matches variations of start line: ## [2.0.0] - some other text
+  if ! $capture && echo $line | grep -oEq "^##\s\[{0,}$version]{0,}\s{0,}.*$"; then
+    capture=true
+  fi
+
+  # Matches variations of stop line: ## [1.0.0] - some other text
+  if $capture && [ -n "$content" ] && echo $line | grep -oEq "^##\s\[{0,}.*]{0,}\s{0,}.*$"; then
+    capture=false
+  fi
+
+  # Matches markdown links at bottom of file: [1.0.0]: https://...
+  if $capture && [ -n "$content" ] && echo $line | grep -oEq "^\[.*$"; then
+    capture=false
+  fi
+
+  [ $capture = true ] && content+="$line"$'\n'
+
+done <"task-input/$CHANGELOG_FILE"
+
+echo "$content" > task-output/${RELEASE_NOTES_FILE}
+
+echo "Release Notes:"
+echo "-------------"
+cat task-output/${RELEASE_NOTES_FILE}

generate-release-notes-from-changelog/task.yml

@@ -0,0 +1,24 @@
+---
+platform: linux
+
+image_resource:
+  type: docker-image
+  source:
+    repository: concourse/git-resource
+
+params:
+  CHANGELOG_FILE: CHANGELOG.md
+  VERSION_FILE: version
+  RELEASE_NOTES_FILE: RELEASE_NOTES.md
+  DEBUG: false
+
+inputs:
+- name: pipeline-tasks
+- name: task-input
+- name: version
+
+outputs:
+- name: task-output
+
+run:
+  path: pipeline-tasks/generate-release-notes-from-changelog/task.sh