GitLab CI: Update MR With Jira Issue Id

In my previous article, we enforced branch names and commit messages to certain rules. Now I will go a step further. When an MR is opened, if there is a Jira issue id (eg. ISSUE-0000) in the title, we will pull the Jira title and description and update MR. CI will fail if there is no Jira Issue Id in the title.

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To do this, we can briefly follow these steps.

1. Check if there is an issue id in the MR title. Otherwise, return fail exit code. We will use regex for this. $CI_MERGE_REQUEST_TITLE will give us the MR header.
2. Extract Issue Id and pull data from Jira API. When you make a GET request to the https://jira.<your-hostname>/rest/api/2/issue/ISSUE-0000 Jira address, Issue details will be returned to you as JSON.
3. Take the summary and description parts from the JSON data returned by Jira API with jq and assign them to variables.
4. Update MR's title and description using GitLab API.

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Curl ve jq Setup

We need curl for our API requests and jq to parse JSON.

apk add --update curl && apk add --update jq && rm -rf /var/cache/apk/*

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Issue Id Check

REGEX_ISSUE_ID="^(ISSUE-[0-9]+)"
ISSUE_ID_IN_MR=$(echo "$CI_MERGE_REQUEST_TITLE" | grep -o -E "$REGEX_ISSUE_ID")
[[ -z "$ISSUE_ID_IN_MR" ]]; then exit 1; fi 

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Jira Issue Parsing

We store new lines (eg. \n) as characters in DESCRIPTION_JSON variable because newlines are the problem when sending curl requests.

JSON=$(curl -s -u <jira-username>:<jira-password> -X GET -H "Content-Type:application/json" "https://jira.<your-hostname>/rest/api/2/issue/$ISSUE_ID_IN_MR")

SUMMARY=$(echo "$JSON" | jq -r ".fields.summary")
DESCRIPTION=$(echo "$JSON" | jq -r ".fields.description")
DESCRIPTION_JSON=$(jq --null-input --compact-output --arg msg "$DESCRIPTION" '$msg')

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Updating Merge Request

You need a private token for this check GitLab documentation and learn how to do that.

curl -v \
--data "{\"title\": \"${ISSUE_ID_IN_MR} ${SUMMARY}\"\"description\": ${DESCRIPTION_JSON}}" \
--fail \
--header "Content-Type:application/json; charset=utf-8" \
--header "PRIVATE-TOKEN:<private-token>" \
--output "/dev/null" \
--request PUT \
--show-error \
--silent \
--trace-ascii "/dev/stderr" \
--write-out "HTTP response: %{http_code}\n\n" \
"${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/merge_request$CI_MERGE_REQUEST_IID"

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Result

When we combine all this into one GitLab CI yml file it will look like this.

check_mr:
  image: alpine
  stage: test
  script:
    - apk add --update curl && apk add --update jq && rm -rf /var/cache/apk/*
    - IFS=$"\n"
    - REGEX_ISSUE_ID="^(ISSUE-[0-9]+)"
    - ISSUE_ID_IN_MR=$(echo "$CI_MERGE_REQUEST_TITLE" | grep -o -E "$REGEX_ISSUE_ID")
    - if [[ -z "$ISSUE_ID_IN_MR" ]]; then exit 1; fi 
    - JSON=$(curl -s -u <jira-username>:<jira-password> -X GET -H "Content-Type:application/json" "https://jira.<your-hostname>/rest/api/2/issue/$ISSUE_ID_IN_MR")
    - SUMMARY=$(echo "$JSON" | jq -r ".fields.summary")
    - DESCRIPTION=$(echo "$JSON" | jq -r ".fields.description")
    - DESCRIPTION_JSON=$(jq --null-input --compact-output --arg msg "$DESCRIPTION" '$msg')
    - |
      curl -v \
      --data "{\"title\": \"${ISSUE_ID_IN_MR} ${SUMMARY}\", \"description\": ${DESCRIPTION_JSON}}" \
      --fail \
      --header "Content-Type:application/json; charset=utf-8" \
      --header "PRIVATE-TOKEN:<private-token>" \
      --output "/dev/null" \
      --request PUT \
      --show-error \
      --silent \
      --trace-ascii "/dev/stderr" \
      --write-out "HTTP response: %{http_code}\n\n" \
      "${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/merge_requests/$CI_MERGE_REQUEST_IID"
    only:
      - merge_requests

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You should add this file you created to your GitLab project as a CI file. After all these processes, your MR titles and descriptions will now be much more organized and understandable!