Sharing the Renovate configuration across multiple projects

Renovate is a tool that helps keep your dependencies up-to-date. You configure it using a configuration file at the root of each repository. This post covers how to share that configuration across multiple projects.

Maintaining the same configuration across multiple repositories is error-prone and time-consuming. Sharing the configuration centralizes the logic and makes it easier to maintain.

Sharing is also valuable in a corporate environment to enforce rules across all repositories. For example, you may want to ensure all Docker images are pulled from a specific internal registry. Renovate can enforce this by automatically updating Docker image names in the Dockerfile. You can also replace deprecated packages by creating rules such as: replace my_old_package with my_new_package. Sharing these rules ensures all repositories stay consistent automatically.

Renovate uses the concept of presets: a named set of rules for updating dependencies. You can create a preset and share it across multiple projects. Presets can be hosted on GitHub, GitLab, Bitbucket, or a custom URL. This post shows how to host a preset on GitHub.

#How to share the configuration?

1. Create a GitHub repository to host the preset. The common name for this repository is renovate-config. Renovate auto-detects this repository when onboarding a project in the same GitHub organization.

2. Create a file named default.json in the repository. The file contains the configuration for Renovate. Here's an example of the configuration:

   JSONcopy

   {
     "description": "Meziantou's default preset",
     "extends": [
       "config:recommended",
       "schedule:nonOfficeHours",
       ":semanticCommits",
       ":enableVulnerabilityAlerts",
       "docker:pinDigests",
       "helpers:pinGitHubActionDigests",
       ":pinDevDependencies"
     ],
     "packageRules": [
       {
         "matchPackageNames": ["alpine"],
         "matchCategories": ["docker"],
         "replacementName": "docker.io/alpine"
       },
       {
         "matchPackageNames": ["Sample.DeprecatedPackage"],
         "matchCategories": ["nuget"],
         "replacementName": "Sample.NewPackage"
       }
     ]
   }

3. Reference the configuration in your project by creating a renovate.json file at the root of the repository. To reference a shared configuration hosted on GitHub, use the extends property with the value github>{GitHub Repository}:{file name}. {GitHub Repository} is the GitHub project path (e.g., meziantou/renovate-config), and {file name} is the name of the file in the repository. The {file name} part is optional; if omitted, Renovate defaults to default.json. The two examples below show renovate.json files referencing default.json and custom_preset.json5 respectively:

   JSONcopy

   {
       "$schema": "https://docs.renovatebot.com/renovate-schema.json",
       "extends": ["github>meziantou/renovate-config"]
   }

   JSONcopy

   {
       "$schema": "https://docs.renovatebot.com/renovate-schema.json",
       "extends": ["github>meziantou/renovate-config:custom_preset.json5"]
   }

For repository-specific settings, add them to the renovate.json file. Local configuration takes precedence over the shared preset.

#Additional resources

• Shareable Config Presets

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