github.com/kyma-project/kyma-environment-broker@v0.0.1/scripts/label_validator.sh

#!/usr/bin/env bash

# standard bash error handling
set -o nounset  # treat unset variables as an error and exit immediately.
set -o errexit  # exit immediately when a command fails.
set -E          # must be set if you want the ERR trap
set -o pipefail # prevents errors in a pipeline from being masked

GITHUB_ORG="kyma-project"

# From Github API Docs on why use API for Issue
#   You can use the REST API to create comments on issues and pull requests. Every pull request is an issue, but not every issue is a pull request.

# Event which triggers execution of script. Can be RELEASE or PR
TRIGGER_EVENT=$1 
PR_ID=${2:-NA}

function runOnRelease() {
  latest=$(curl -sL \
                -H "X-GitHub-Api-Version: 2022-11-28" \
                -H "Authorization: Bearer ${GITHUB_TOKEN}" \
                -sS "https://api.github.com/repos/$GITHUB_ORG/kyma-environment-broker/releases/latest" |
                jq -r 'if has("tag_name") then .tag_name else empty end')

  if [[ -z $latest ]]; then 
    echo 'not found latest release, nothing to compare'
    exit 1
  fi 

  echo "latest release found: $latest"

  supported_labels=$(yq eval '.changelog.categories.[].labels' ./.github/release.yml | grep "\- kind"| sed -e 's/- //g' | cut -d "#" -f 1)
  supported_labels=$(echo "${supported_labels[*]}" | tr " " "\n" )

  notValidPrs=()
  while read -r commit; do
    if [[ -z $commit ]]; then 
      continue
    fi
        
    pr_id=$(curl -sL \
              -H "Accept: application/vnd.github+json" \
              -H "X-GitHub-Api-Version: 2022-11-28" \
              -H "Authorization: Bearer ${GITHUB_TOKEN}" \
              "https://api.github.com/search/issues?q=$commit+repo:$GITHUB_ORG/btp-manager+type:pr" |
              jq 'if (.items | length) == 1 then .items[0].number else empty end')

    if [[ -z $pr_id ]]; then
      echo "not found PR for commit $commit"
      continue
    fi 

    echo "for commit $commit found PR $pr_id"

    if [[ " ${notValidPrs[*]} " =~ " ${pr_id} " ]]; then
       continue
    fi

    present_labels=$(curl -sL \
                    -H "Accept: application/vnd.github+json" \
                    -H "X-GitHub-Api-Version: 2022-11-28" \
                    https://api.github.com/repos/$GITHUB_ORG/btp-manager/issues/${pr_id} | 
                    jq -r 'if (.labels | length) > 0 then .labels[] | objects | .name else empty end')
                    
    if [[ -z $present_labels ]]; then 
      echo "PR $pr_id dosent have any label"
      notValidPrs+=("$pr_id")
      continue
    fi 

    count_of_required_labels=$(grep -o -w -F -c "${supported_labels}" <<< "$present_labels" || true)
    if [[ $count_of_required_labels -eq 0 ]]; then 
      echo "PR $pr_id dosent have any /kind label"
      notValidPrs+=("$pr_id")
      continue
    fi
    if [[ $count_of_required_labels -gt 1 ]]; then 
      (echo -n "PR $pr_id have $count_of_required_labels /kind labels -> " && echo $present_labels | tr "," "\t")
      notValidPrs+=("$pr_id")
      continue
    fi
    echo "commit $commit in PR $pr_id have 1 label $present_labels"
  done <<< "$(git log "$latest"..HEAD --pretty=tformat:"%h")"

  if [ ${#notValidPrs[@]} -gt 0 ]; then
      echo "following PRs do not have correct number of /kind labels"
      for pr in "${notValidPrs[@]}"
      do
        echo "https://github.com/$GITHUB_ORG/btp-manager/pull/$pr"
      done
      exit 1
  fi

  echo "label validation OK"
  exit 0
} 

function runOnPr() {
  if [[ $PR_ID == "NA" ]]; then
    echo "PR ID not passed"
    exit 1
  fi

  supported_labels=()

  help_message="**Add one of following labels** <br/><br/>"

  while IFS= read -r label; do
    parts=$(tr "#" " " <<< "$label")
    set $parts
    label_part=$1; help_message_part=$@
    help_message="${help_message} - $label_part -> $help_message_part <br/><br/>"
    supported_labels+=($label_part)
  done <<< "$(yq eval '.changelog.categories.[].labels' ./.github/release.yml | grep "\- kind"| sed -e 's/- //g')"
  supported_labels=$(echo "${supported_labels[*]}" | tr " " "\n" )
  
  comments=$(curl -sL \
              -H "Accept: application/vnd.github+json" \
              -H "X-GitHub-Api-Version: 2022-11-28" \
              -H "Authorization: Bearer ${GITHUB_TOKEN}" \
              https://api.github.com/repos/$GITHUB_ORG/btp-manager/issues/${PR_ID}/comments |
              jq -r 'if (.[] | length) > 0 then .[] | objects | .body else empty end')

  if [[ ! " ${comments[*]} " =~ " ${help_message} " ]]; then

    payload=$(jq -n \
      --arg body "$help_message" \
      '{
        "body": $body,
      }') 

    response=$(curl -sL \
            -X POST \
            -H "Accept: application/vnd.github+json" \
            -H "Authorization: Bearer ${GITHUB_TOKEN}" \
            -H "X-GitHub-Api-Version: 2022-11-28" \
            https://api.github.com/repos/$GITHUB_ORG/btp-manager/issues/${PR_ID}/comments \
            -d "$payload")

    echo "create comment with help result: $response"
  fi

  present_labels=$(curl -sL \
                    -H "Accept: application/vnd.github+json" \
                    -H "X-GitHub-Api-Version: 2022-11-28" \
                    -H "Authorization: Bearer ${GITHUB_TOKEN}" \
                    https://api.github.com/repos/$GITHUB_ORG/btp-manager/issues/${PR_ID} | 
                    jq -r 'if (.labels | length) > 0 then .labels[] | objects | .name else empty end')

  count_of_required_labels=$(grep -o -w -F -c "${supported_labels}" <<< "$present_labels" || true)
  if [[ $count_of_required_labels -eq 1 ]]; then 
    echo "label validation OK"
    exit 0
  fi

  echo "error: only 1 of following labels must be added to each PR before merge but found $count_of_required_labels:"
  echo "${supported_labels}"
  exit 1
}

case $TRIGGER_EVENT in
  "RELEASE")
    runOnRelease
    ;;
  "PR")
    runOnPr
    ;;
  *)
    echo "unsupported trigger event: $TRIGGER_EVENT"
    exit 1
    ;;
esac