Migrating labels between GitLab instances can be a daunting task, especially when dealing with numerous projects. Labels are crucial for organizing issues and merge requests, and ensuring they are consistent across instances is essential for maintaining workflow efficiency. This article will guide you through the process of migrating labels from one GitLab instance to another using GitLab’s API and a simple Python script.

Prerequisites

Before you begin, ensure you have the following:

1. Access to both GitLab instances: You need to have the necessary permissions to access the API on both the source and destination GitLab instances.

2. API Tokens: Generate personal access tokens for both instances with the necessary scopes (at least api scope).

3. Python Environment: Ensure you have Python installed on your machine along with the requests library. You can install it using pip:

   pip install requests
   

Step 1: Fetch Labels from the Source Instance

First, you’ll need to fetch the labels from the source GitLab instance. The following Python script will help you do that:

import requests

SOURCE_GITLAB_URL = 'https://source.gitlab.com'
SOURCE_PROJECT_ID = 'your-source-project-id'
SOURCE_API_TOKEN = 'your-source-api-token'

def fetch_labels():
    headers = {'PRIVATE-TOKEN': SOURCE_API_TOKEN}
    response = requests.get(f'{SOURCE_GITLAB_URL}/api/v4/projects/{SOURCE_PROJECT_ID}/labels', headers=headers)
    
    if response.status_code == 200:
        return response.json()
    else:
        raise Exception(f"Failed to fetch labels: {response.status_code} - {response.text}")

labels = fetch_labels()
print("Fetched labels:", labels)

Replace SOURCE_GITLAB_URL, SOURCE_PROJECT_ID, and SOURCE_API_TOKEN with your source instance details.

Step 2: Create Labels in the Destination Instance

Once you have the labels, the next step is to create them in the destination GitLab instance. Use the following script to achieve this:

DESTINATION_GITLAB_URL = 'https://destination.gitlab.com'
DESTINATION_PROJECT_ID = 'your-destination-project-id'
DESTINATION_API_TOKEN = 'your-destination-api-token'

def create_label(label):
    headers = {'PRIVATE-TOKEN': DESTINATION_API_TOKEN}
    data = {
        'name': label['name'],
        'color': label['color'],
        'description': label.get('description', '')
    }
    response = requests.post(f'{DESTINATION_GITLAB_URL}/api/v4/projects/{DESTINATION_PROJECT_ID}/labels', headers=headers, json=data)
    
    if response.status_code == 201:
        print(f"Label '{label['name']}' created successfully.")
    else:
        print(f"Failed to create label '{label['name']}': {response.status_code} - {response.text}")

for label in labels:
    create_label(label)

Replace DESTINATION_GITLAB_URL, DESTINATION_PROJECT_ID, and DESTINATION_API_TOKEN with your destination instance details.

Step 3: Verify the Migration

After running the scripts, verify that all labels have been successfully migrated to the destination instance. You can do this by checking the labels section in your destination project settings.

Conclusion

Migrating labels between GitLab instances can be efficiently handled using GitLab’s API and a bit of Python scripting. This approach not only saves time but also ensures accuracy and consistency across your projects. By automating the process, you reduce the risk of human error and streamline your DevOps workflows.

References

• GitLab API Documentation
• Python Requests Library

By following this guide, you can ensure a smooth transition of labels between GitLab instances, maintaining the integrity and organization of your projects.