react-native-windows/packages/react-native-platform-override

react-native-platform-override

Tools to manage "platform overrides" for out of tree React Native platforms. Facilities for inventorying changes and integrating new upstream changes are included.

Override Manifests

react-native-platform-override operates on a JSON "override manifest" placed at the root of an npm package. It is expected that these are named overrides.json.

An example override manifest

{
  "includePatterns": [
    "src/**"
  ],
  "excludePatterns": [
    "src/README.md"
  ],
  "baseVersion": "0.0.0-10b4b9505",
  "overrides": [
    {
      "type": "derived",
      "file": ".flowconfig",
      "baseFile": ".flowconfig",
      "baseVersion": "0.0.0-56cf99a96",
      "baseHash": "8eab29258f5ad573e478324f10f850b7ccfb49c7"
    },
  ]
}

Name	Required	Description	Default
includePatterns	Optional	A list of globs of files to enforce are listed in the manifest.	["**"]
excludePatterns	Optional	Globs to be excluded from the above list.	[]
baseVersion	Optional	The default react-native version of an override
overrides	Required	List of registered overrides, added by the tooling

Override Types

Overrides can be registered as different types, each with differing behavior.

Platform	Platform-specific logic that doesn't map to an upstream file
Derived	An override derived from an upstream file. Changes to the original file will be merged into the override.
Patch	An upstream file with changes made to it. Changes to the original file will be merged into the override.
Copy	An exact copy of an upstream file or directory. Overrides of this type will remain identical to their originals.

CLI

react-native-platform-override offers multiple commands to manipulate and verify the override manifest.

validate

Verifies that overrides are recorded and up-to-date.

Option	Required	Description	Default
--manifest <file>	Optional	Path to an override manifest to validate	Package root above cwd
--version <v>	Optional	A version of React Native to check against	The currently installed version

add <override>

Adds an override to the manifest, prompting for details.

Option	Required	Description
<override>	Required	The override to add

remove <override>

Removes an override to the manifest.

Option	Required	Description
<override>	Required	The override to remove

upgrade

Attempts to automatically merge new changes into out-of-date overrides.

Option	Required	Description	Default
--manifest <file>	Optional	Path to an override manifest to validate	Package root above cwd
--version <v>	Optional	A version of React Native to check against	The currently installed version
--no-conflicts	Optional	Whether to allow upgraded files to contain conlict markers	--conflicts

diff <override>

Diffs an override against its base file. It it compared to the base file of the override's current version, even if a newer verison of react-native is installed.

Option	Required	Description	Default
<override>	Required	The override to diff against

GitHub Tokens

react-native-platform-override makes requests to GitHub's API. An OAuth token may optionally be provided by using the --githubToken parameter or setting the PLATFORM_OVERRIDE_GITHUB_TOKEN environment variable.

Programmatic Use

react-native-platform-override offers a programmatic API with similar capabilities to the CLI. Take a look here for details.

E.g.

import {validateManifest} from 'react-native-platform-override';

const validationErrors = await validateManifest({manifestPath: 'src/overrides.json'});