go.uber.org/yarpc@v1.72.1/etc/bin/update-deps.sh

#!/usr/bin/env bash
set -euo pipefail
IFS=$'\n\t'

# This script will update the dependencies for the branch that it was executed
# with. If the update didn't cause any generated code to change and the tests
# continue to pass, the change will be pushed directly to the branch. If the
# generated code changed or the tests failed, the change will be pushed to a
# new branch and a pull request will be created.
#
# Variables to control the behavior of this script:
#
# GITHUB_USER (required)
#   GitHub username used to authenticate requests.
# GITHUB_TOKEN (required)
#   GitHub token to authenticate $GITHUB_USER.
# GITHUB_EMAIL (optional)
#   Email address of the GitHub user.
# GITHUB_REPO (optional)
#   GitHub repository in the form $user/$repo. This will usually be inferred
#   automatically from BUILDKITE_REPO.
# GIT_REMOTE (optional)
#   Name of the git remote to which changes will be pushed. Defaults to
#   "origin".
#
# The following variables set by BuildKite are also accepted.
#
#   BUILDKITE_BRANCH
#   BUILDKITE_BUILD_CREATOR (optional)
#   BUILDKITE_BUILD_CREATOR_EMAIL (optional)
#   BUILDKITE_BUILD_NUMBER (optional)
#   BUILDKITE_REPO (optional)
#
# See https://buildkite.com/docs/builds/environment-variables for what they mean.
#
# Either BUILDKITE_BUILD_CREATOR_EMAIL or GITHUB_EMAIL must be present. If
# BUILDKITE_BUILD_CREATOR_EMAIL was specified, BUILDKITE_BUILD_CREATOR must
# also be present.

if [ -z "${GITHUB_USER:-}" ] || [ -z "${GITHUB_TOKEN:-}" ]; then
  echo "GITHUB_USER or GITHUB_TOKEN is unset."
  echo "Please set these variables."
  exit 1
fi

if [ -z "${BUILDKITE_BRANCH:-}" ]; then
  echo "BUILDKITE_BRANCH is unset. Is this running on BuildKite?"
  exit 1
fi

AUTHOR="$GITHUB_USER"
EMAIL=""
if [ -z "${GITHUB_EMAIL:-}" ]; then
  if [ -z "${BUILDKITE_BUILD_CREATOR_EMAIL:-}" ]; then
    echo "Either GITHUB_EMAIL or BUILDKITE_BUILD_CREATOR_EMAIL is required."
    exit 1
  elif [ -z "${BUILDKITE_BUILD_CREATOR:-}" ]; then
    echo "BUILDKITE_BUILD_CREATOR is required if BUILDKITE_BUILD_CREATOR_EMAIL was provided."
    exit 1
  else
    # If we're using the build creator's email address, we should use their name
    # too.
    AUTHOR="$BUILDKITE_BUILD_CREATOR"
    EMAIL="$BUILDKITE_BUILD_CREATOR_EMAIL"
  fi
else
  EMAIL="$GITHUB_EMAIL"
fi


export GIT_AUTHOR_NAME="$AUTHOR"
export GIT_COMMITTER_NAME="$AUTHOR"
export GIT_AUTHOR_EMAIL="$EMAIL"
export GIT_COMMITTER_EMAIL="$EMAIL"

REMOTE="${GIT_REMOTE:-origin}"
BRANCH="$BUILDKITE_BRANCH"

GITHUB_REPO=${GITHUB_REPO:-}
if [ -z "$GITHUB_REPO" ]; then
  case "${BUILDKITE_REPO:-}" in
    "git@github.com:"*)
      GITHUB_REPO="${BUILDKITE_REPO#git@github.com:}"
      GITHUB_REPO="${GITHUB_REPO%.git}"
      ;;
    "https://github.com/"*)
      GITHUB_REPO="${BUILDKITE_REPO#https://github.com/}"
      GITHUB_REPO="${GITHUB_REPO%.git}"
      ;;
    *)
      echo "Could not determine GITHUB_REPO from BUILDKITE_REPO."
      echo "You can set it explicitly if you're not running this from CI."
      exit 1
  esac
fi

# When pushing over ssh, automatically add the host to known_hosts instead of
# prompting with,
#
#   The authenticity of host '...' can't be established.
#   RSA key fingerprint is ...
#   Are you sure you want to continue connecting (yes/no)?
export GIT_SSH_COMMAND="ssh -o StrictHostKeyChecking=no"

# Returns the current date in ISO8601 format.
now() {
  date +%Y-%m-%dT%H:%M:%S
}

changed_files()
{
  # BuildKite's docker-compose plugin generates a fake docker-compose so we
  # need to ignore it anytime we do git status.
  git --no-pager diff --name-only "$@" | grep -v '^docker-compose.buildkite'
}

# update_module $DIR updates the Go module in $DIR.
update_module()
{
  echo "--- Updating module $1"
  (cd "$1" && go get -u all && go mod tidy)
  if [ -n "$(changed_files)" ]; then
    git add --verbose "$1/go.mod" "$1/go.sum"
  fi
}

if [ -n "$(changed_files)" ]; then
  echo "Working tree is dirty."
  echo "Please verify that you don't have any uncommitted changes."
  git status
  exit 1
fi

echo "--- Updating dependencies"
update_module "."
update_module "internal/examples"
update_module "internal/crossdock"

if [ -z "$(changed_files --staged)" ]; then
  echo "Nothing changed. Exiting."
  exit 0
fi

echo "--- Committing update"
git commit -m "Update dependencies at $(now)"

echo "--- Updating generated code"
make generate

# Generated code might affect dependencies.
go mod tidy
(cd internal/examples && go mod tidy)
(cd internal/crossdock && go mod tidy)

# We want to push directly to the remote only if the generated code did not
# change and all tests pass.
if [ -z "$(changed_files)" ]; then
  if make lint test examples; then
    echo "--- Generated code did not change and the tests passed."
    echo "--- Pushing changes and exiting."
    git push "$REMOTE" HEAD:"$BRANCH"
    exit 0
  fi
else
  # Check in the generated code ignoring the BuildKite docker-compose.
  changed_files | xargs git add --verbose
  git commit -m "Update generated code at $(now)"
fi

PR_BRANCH=""
if [ -z "${BUILDKITE_BUILD_NUMBER:-}" ]; then
  # Use a different branch namespace if we're not running in BuildKite.
  PR_BRANCH="update-deps/$(now)"
else
  PR_BRANCH="update-deps/buildkite/$BUILDKITE_BUILD_NUMBER"
fi

echo "--- Creating a pull request using branch $PR_BRANCH"
git push "$REMOTE" HEAD:"refs/heads/$PR_BRANCH"

# This needs to be a function so that we can pipe into it from the python
# command with the heredoc without making an overly long line. That is, we
# want to avoid,
#
#   python - foo bar <<EOF | curl --user ... -X POST [very long line]
create_pull_request()
{
  curl --user "$GITHUB_USER:$GITHUB_TOKEN" -X POST \
    --data @- "https://api.github.com/repos/$GITHUB_REPO/pulls"
}

python - "$PR_BRANCH" "$BRANCH" <<EOF | create_pull_request
import sys, json

print(json.dumps({
  "title": "Update dependencies on $(now)",
  "head": sys.argv[1],
  "base": sys.argv[2],
  "maintainer_can_modify": True,
  "body": """I tried to update the dependencies but either the generated
code changed or some tests failed, so I need someone to validate or fix this
change.

Thanks!""",
}))
EOF

# vim:ts=2 sw=2 et: