Add git cliff toml to support generation of changelog

CONTRIBUTING.md

@@ -85,6 +85,25 @@ All PRs require an approval from at least one CODEOWNER before merge. PRs which
 - If you sat down with the PR submitter and did a pairing review please note that in the `Approval`, or your PR comments.
 - If you are only making "surface level" reviews, submit any notes as `Comments` without adding a review.
 
+### Commit Messages
+
+Commit messages should be [conventional](https://www.conventionalcommits.org/en/v1.0.0/).
+
+The commit message type should be one of:
+
+* `feat` / `feature` for feature work.
+* `bug` / `fix` for bug fixes.
+* `imp` / `improvements` for improvements.
+* `doc` / `docs` / `documentation` for any documentation changes.
+* `test` / `e2e` for any tests added.
+* `deprecated` for deprecation changes.
+* `deps` / `build` for changes to dependencies.
+* `chore` / `misc` / `nit` for any miscellaneous changes that don't fit into another category.
+
+**Note**: If any change breaking, the following format must be used:
+* `type` + `(api)!` for api breaking changes, e.g. `fix(api)!: api breaking fix`
+* `type` + `(statemachine)!` for state machine breaking changes, e.g. `fix(statemachine)!: state machine breaking fix`
+
 ### Updating Documentation
 
 If you open a PR on ibc-go, it is mandatory to update the relevant documentation in /docs.

Makefile

@@ -171,6 +171,10 @@ view-docs:
 		@cd docs && \
     npm install && npm run serve
 
+
+changelog:
+	docker run --rm -v "$$(pwd)"/.git:/app/ -v "$$(pwd)/cliff.toml":/app/cliff.toml orhunp/git-cliff:latest --unreleased --tag $(tag)
+
 .PHONY: build-docs
 
 ###############################################################################

cliff.toml

@@ -0,0 +1,99 @@
+# configuration file for git-cliff (0.1.0)
+
+[changelog]
+# changelog header
+header = """
+<!--
+Usage:
+
+Change log entries are generated by git cliff ref: https://github.com/orhun/git-cliff
+This can be run using "make changelog tag=vx.y.z"
+
+Each commit should be conventional, the following message groups are supported.
+
+* feat, feature
+* imp
+* bug, fix
+* deprecated
+* (api)!
+* (statemachine)!
+
+Types of changes (Stanzas):
+
+"Features" for new features. (feat, feature)
+"Improvements" for changes in existing functionality. (imp)
+"Deprecated" for soon-to-be removed features.
+"Bug Fixes" for any bug fixes. (bug, fix)
+"API Breaking" for breaking exported APIs used by developers building on SDK. Add (api)! e.g. fix(api)!: api breaking fix
+"State Machine Breaking" for any changes that result in a different AppState given same genesisState and txList. Add (statemachine)! e.g. fix(statemachine)!: state machine breaking fix
+Ref: https://keepachangelog.com/en/1.0.0/
+-->
+
+# Changelog
+All notable changes to this project will be documented in this file.
+"""
+# template for the changelog body
+# https://tera.netlify.app/docs/#introduction
+body = """
+{% if version %}\
+    ## [{{ version | trim_start_matches(pat="v") }}] - {{ timestamp | date(format="%Y-%m-%d") }}
+{% else %}\
+    ## [unreleased]
+{% endif %}\
+{% for group, commits in commits | group_by(attribute="group") %}
+    ### {{ group | striptags | trim | upper_first }}
+    {% for commit in commits %}
+        * {{ commit.message | upper_first }}\
+    {% endfor %}
+{% endfor %}\n
+"""
+# remove the leading and trailing whitespace from the template
+trim = true
+# changelog footer
+footer = """
+<!-- generated by git-cliff -->
+"""
+
+[git]
+# parse the commits based on https://www.conventionalcommits.org
+conventional_commits = true
+# filter out the commits that are not conventional
+filter_unconventional = true
+# process each line of a commit as an individual commit
+split_commits = false
+# regex for preprocessing the commit messages
+commit_preprocessors = [
+    # A reference to an issue is appened to commits that looks like "(#1234)", this will be replaced
+    # with a link to that issue, e.g. "[#$1234](https://github.com/cosmos/ibc-go/issues/1234)".
+    { pattern = '\((\w+\s)?#([0-9]+)\)', replace = "([#${2}](https://github.com/cosmos/ibc-go/issues/${2}))" },
+    # any reference to a pr like "pr-1234" will be replaced with a link to the PR.
+    { pattern = '\(pr-([0-9]+)\)', replace = "([#${1}](https://github.com/cosmos/ibc-go/pulls/${1}))" },
+]
+# regex for parsing and grouping commits
+commit_parsers = [
+    # specifying the number in a comment is a workaround to enable ordering of groups.
+    # these comments are stripped out of the markdown with the filter "{{ group | striptags | trim | upper_first }}"
+    # above in the body template.
+    { message = "^((?i)deps|(?i)dep|(?i)build)", group = "<!-- 0 -->Dependencies" },
+    { message = '^.*\(api\)!', group = "<!-- 1 -->API Breaking" },
+    { message = '^.*\(statemachine\)!', group = "<!-- 2 -->State Machine Breaking" },
+    { message = "^((?i)improvements|(?i)imp)", group = "<!-- 3 -->Improvements" },
+    { message = "^((?i)feature|(?i)feat)", group = "<!-- 4 -->Features" },
+    { message = "^((?i)fix|(?i)bug)", group = "<!-- 5 -->Bug Fixes" },
+    { message = "^((?i)doc|(?i)docs|(?i)documentation)", group = "<!-- 6 -->Documentation" },
+    { message = "^((?i)test|(?i)e2e)", group = "<!-- 7 -->Testing" },
+    { message = "^((?i)deprecated)", group = "<!-- 8 -->Deprecated" },
+    { message = "^((?i)chore|(?i)misc|(?i)nit)", group = "<!-- 9 -->Miscellaneous Tasks" },
+]
+# filter out the commits that are not matched by commit parsers
+filter_commits = false
+# glob pattern for matching git tags
+tag_pattern = "v[0-9]*"
+# regex for skipping tags
+skip_tags = ""
+# regex for ignoring tags
+ignore_tags = ""
+# sort the tags chronologically
+date_order = false
+# sort the commits inside sections by oldest/newest order
+sort_commits = "oldest"