Pre-commit hook to validate a .gitlab-ci.yml by uploading to gitlab server and validating using API

pre-commit

#!/usr/bin/env bash

###########################
# Validate .gitlab-ci.yml #
#    by  Peter Weinert    #
###########################

lif [[ "$OSTYPE" == "darwin"* ]]; then
  SED_BIN="gsed"
  command -v "gsed" >/dev/null 2>&1 || { echo >&2 "I require gsed but it's not installed. Install with 'brew install gnu-sed'.  Aborting."; exit 1; }
else
  SED_BIN="sed"
fi

# https://gitlab.lrz.de/snippets/234

GITLAB_URL="https://your.gitlab.com"
GITLAB_API_LINT="${GITLAB_URL}/api/v4/ci/lint"
GITLAB_WEB_LINT="${GITLAB_URL}/ci/lint"

ANSI_RED="\e[31m"
ANSI_YELLOW="\e[33m"
ANSI_LIGHT="\e[1m"
ANSI_OFF="\e[0m"

# Check if .gitlab-ci.yml is added or modified in index
CI_CHANGED=`git diff-index --name-only --diff-filter MA HEAD | grep '^.gitlab-ci.yml$'`

if [ ! -z "$CI_CHANGED" ]
then
  # checkout from index to a temporary file named $temp_file
  temp_file_assoc=$(git checkout-index --temp -- .gitlab-ci.yml)
  set -f
  temp_file=($temp_file_assoc)
  set +f
  temp_file=${temp_file[0]}
  trap "rm -f $temp_file" EXIT INT TERM

  # Sanitize: read the whole file in a loop (:a;N;$!ba), see https://stackoverflow.com/questions/1251999/how-can-i-replace-a-newline-n-using-sed
  # and escape special json characters (\ \f \n \r \t / ") with a backslash.
  SANE_CONTENT="$( cat "$temp_file" | "$SED_BIN" -e ':a' -e 'N' -e '$!ba' -e 's/\\/\\\\/g' -e 's/\f/\\f/g' -e 's/\n/\\n/g' -e 's/\r/\\r/g' -e 's/\t/\\t/g' -e 's/\//\\\//g' -e 's/"/\\"/g' )"
  # Pack YAML in JSON
  JSON="{\"content\": \"${SANE_CONTENT}\"}"

  # Use Lint - if timeout is reached the validation will succeed nevertheless
  ANSWER=`curl -s --connect-timeout 2 --max-time 4 --header "Content-Type: application/json" ${GITLAB_API_LINT} --data "$JSON"`
  ERROR_CODE=$?
  if [[ "$ERROR_CODE" != "0" ]]; then
    echo -e "${ANSI_LIGHT}${ANSI_YELLOW}WARNING: .gitlab-ci.yml not validated!${ANSI_OFF} Curl failed with error code ${ANSI_LIGHT}${ANSI_RED}${ERROR_CODE}${ANSI_OFF}" >&2
  else
    if [[ $ANSWER =~ "invalid" ]]; then
      echo -e "${ANSI_LIGHT}${ANSI_RED}ERROR: Invalid .gitlab-ci.yml.${ANSI_OFF} Lint reports ${ANSWER}." >&2
      echo -e "Use your Gitlab Lint (${GITLAB_WEB_LINT}) for more information." >&2
      echo -e "Aborting commit." >&2
      exit 1
    elif [[ ! $ANSWER =~ "valid" ]]; then
      echo -e "${ANSI_LIGHT}${ANSI_YELLOW}WARNING: No regular answer received.${ANSI_OFF} Lint reports '${ANSWER}'." >&2
      echo -e "This is most likely a bug in the JSON to YAML converter section of this script." >&2
      echo -e "Please report includung the exact .gitlab-ci.yml." >&2
      echo -e "Data send was (backslashes escaped) $( echo "$JSON" | "$SED_BIN" -e 's/\\/\\\\/g' )" >&2
#   else
#     echo -e "File .gitlab-ci.yml is valid."
    fi
  fi
fi