text: # Datasources
  
  Datasources are used in Renovate primarily to fetch released versions of packages.
  
  ### getReleases
  
  The minimum exported interface for a datasource is a function called `getReleases` that takes a lookup config as input.
  
  The config contains:
  
  - `lookupName`: the package's full name including scope if present (e.g. `@foo/bar`)
  - `registryUrls`: an array of registry Urls to try
  
  `getReleases` should return an object containing:
  
  - `releases`: an array of strings of matched versions. This is the only mandatory field.
  - `deprecationMessage`: a string description of the package's deprecation notice, if applicable
  - `sourceUrl`: a HTTP URL pointing to the source code (e.g. on GitHub)
  - `homepage`: a HTTP URL for the package's homepage. Ideally should be empty if the homepage and sourceUrl are the same
  - `changelogUrl`: a URL pointing to the package's Changelog (could be a markdown file, for example). If not present then Renovate will search the `sourceUrl` for a changelog file.
  - `tags`: an object mapping tag -> version, e.g. `tags: { latest: '3.0.0' }`. This is only used by the `followTags` function.
  
  ### getDigest
  
  Datasources that support the concept of digests (e.g. docker digests and git commit hashes) also can export a `getDigest` function.
  
  The `getDigest` function has two inputs:
  
  - `config`: the Renovate config for the package being updated, contains same fields as `getReleases`
  - `newValue`: the version or value to retrieve the digest for
  
  The `getDigest` function returns a string output representing the digest value. If none is found then a return value of `null` should be returned.
  