mirror_repos

#! /bin/bash

set -ueo pipefail

export AWS_REGION=eu-west-2
export AWS_DEFAULT_REGION=eu-west-2

base_dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"

function with_credentials {
  unset AWS_ACCESS_KEY_ID
  unset AWS_SECRET_ACCESS_KEY
  unset AWS_SESSION_TOKEN
  eval $(./set_credentials)
}

with_credentials

echo "Finding Github repos tagged with 'govuk'..."
repos=$(${base_dir}/get_github_repos)

[[ $(uname) == 'Darwin' ]] && md5=md5 || md5=md5sum

for repo in ${repos}; do

  with_credentials

  git config --global credential.helper '!aws codecommit credential-helper $@'
  git config --global credential.UseHttpPath true

  echo -n "Checking if ${repo} is up to date... "

  github_md5=$(git ls-remote --heads --tags https://${GITHUB_ACCESS_TOKEN}@github.com/alphagov/${repo} | $md5 | cut -d" " -f1)
  aws_cc_md5=$(git ls-remote --heads --tags https://git-codecommit.${AWS_REGION}.amazonaws.com/v1/repos/${repo} | $md5 | cut -d" " -f1)

  if [ ${github_md5} != ${aws_cc_md5} ]; then
    echo "updating"
    git="git --git-dir ${repo}.git"

    github_remote="ssh://git@github.com/alphagov/${repo}"
    aws_remote="ssh://${AWS_CODECOMMIT_USER_ID}@git-codecommit.${AWS_REGION}.amazonaws.com/v1/repos/${repo}"

    echo "Cleaning the workspace"
    rm -rf "${repo}.git"

    echo "Fetching ${repo}"
    ${git} clone --mirror "${github_remote}"

    echo "Doing some cleanup for ${repo}"
    ${git} reflog expire --expire-unreachable=now --all
    ${git} gc            --prune=now

    echo "Pushing latest ${repo} tags"
    ${git} push "${aws_remote}" --force $(git for-each-ref --sort=taggerdate --format '%(refname:short)' refs/tags | tail -4000 | tr '\n' ' ')

    echo "Pushing all ${repo} repo branches"
    ${git} push --force --quiet --all "${aws_remote}"

    echo "Manually pushing ${repo} git heads information"
    ${git} push ${aws_remote} +refs/remotes/origin/*:refs/heads/*

    echo "Deleting local copy ${repo}.git"
    rm -rf "${repo}.git"
  else
    echo "ok"
  fi

  sleep 2
done