expo-constants/src/Constants.ts

Provides system information that remains constant throughout the lifetime of your app.

import type { ExpoConfig } from 'expo/config';
// @ts-ignore -- optional interface, will gracefully degrade to `any` if not installed
import type {
  EmbeddedManifest,
  EASConfig,
  ExpoGoConfig,
  ExpoUpdatesManifest,
  // @ts-ignore -- optional interface, will gracefully degrade to `any` if not installed
} from 'expo-manifests';
import { CodedError, requireOptionalNativeModule } from 'expo-modules-core';
// @ts-ignore -- optional interface, will gracefully degrade to `any` if not installed
import type { Manifest as UpdatesManifest, ExpoUpdatesModule } from 'expo-updates';
import { Platform, NativeModules } from 'react-native';

import {
  AndroidManifest,
  AppOwnership,
  Constants,
  ExecutionEnvironment,
  IOSManifest,
  NativeConstants,
  PlatformManifest,
  UserInterfaceIdiom,
  WebManifest,
} from './Constants.types';
import ExponentConstants from './ExponentConstants';
type DevLauncherManifest = ExpoUpdatesManifest;

export {
  AndroidManifest,
  AppOwnership,
  Constants,
  ExecutionEnvironment,
  IOSManifest,
  NativeConstants,
  PlatformManifest,
  UserInterfaceIdiom,
  WebManifest,
};

if (!ExponentConstants) {
  console.warn(
    "No native ExponentConstants module found, are you sure the expo-constants's module is linked properly?"
  );
}

const ExpoUpdates = requireOptionalNativeModule<ExpoUpdatesModule>('ExpoUpdates');

let rawUpdatesManifest: UpdatesManifest | null = null;
// If expo-updates defines a non-empty manifest, prefer that one
if (ExpoUpdates) {
  let updatesManifest: object | undefined;
  if (ExpoUpdates.manifest) {
    updatesManifest = ExpoUpdates.manifest;
  } else if (ExpoUpdates.manifestString) {
    updatesManifest = JSON.parse(ExpoUpdates.manifestString);
  }
  if (updatesManifest && Object.keys(updatesManifest).length > 0) {
    rawUpdatesManifest = updatesManifest as any;
  }
}

// If dev-launcher defines a non-empty manifest, prefer that one
let rawDevLauncherManifest: DevLauncherManifest | null = null;
if (NativeModules.EXDevLauncher) {
  let devLauncherManifest;
  if (NativeModules.EXDevLauncher.manifestString) {
    devLauncherManifest = JSON.parse(NativeModules.EXDevLauncher.manifestString);
  }

  if (devLauncherManifest && Object.keys(devLauncherManifest).length > 0) {
    rawDevLauncherManifest = devLauncherManifest as any;
  }
}

// Fall back to ExponentConstants.manifest if we don't have one from Updates
let rawAppConfig: ExpoConfig | null = null;
if (ExponentConstants && ExponentConstants.manifest) {
  const appConfig: object | string = ExponentConstants.manifest;

  // On Android we pass the manifest in JSON form so this step is necessary
  if (typeof appConfig === 'string') {
    rawAppConfig = JSON.parse(appConfig);
  } else {
    rawAppConfig = appConfig as any;
  }
}

type RawManifest = UpdatesManifest | DevLauncherManifest | ExpoConfig;
let rawManifest: RawManifest | null = rawUpdatesManifest ?? rawDevLauncherManifest ?? rawAppConfig;

const { name, appOwnership, ...nativeConstants } = (ExponentConstants || {}) as any;

const constants: Constants = {
  ...nativeConstants,
  // Ensure this is null in bare workflow
  appOwnership: appOwnership ?? null,
};

Object.defineProperties(constants, {
  /**
   * Use `manifest` property by default.
   * This property is only used for internal purposes.
   * It behaves similarly to the original one, but suppresses warning upon no manifest available.
   * `expo-asset` uses it to prevent users from seeing mentioned warning.
   */
  __unsafeNoWarnManifest: {
    get(): EmbeddedManifest | null {
      const maybeManifest = getManifest(true);
      if (!maybeManifest || !isEmbeddedManifest(maybeManifest)) {
        return null;
      }
      return maybeManifest;
    },
    enumerable: false,
  },
  __unsafeNoWarnManifest2: {
    get(): ExpoUpdatesManifest | null {
      const maybeManifest = getManifest(true);
      if (!maybeManifest || !isExpoUpdatesManifest(maybeManifest)) {
        return null;
      }
      return maybeManifest;
    },
    enumerable: false,
  },
  manifest: {
    get(): EmbeddedManifest | null {
      const maybeManifest = getManifest();
      if (!maybeManifest || !isEmbeddedManifest(maybeManifest)) {
        return null;
      }
      return maybeManifest;
    },
    enumerable: true,
  },
  manifest2: {
    get(): ExpoUpdatesManifest | null {
      const maybeManifest = getManifest();
      if (!maybeManifest || !isExpoUpdatesManifest(maybeManifest)) {
        return null;
      }
      return maybeManifest;
    },
    enumerable: true,
  },
  expoConfig: {
    get():
      | (ExpoConfig & {
          /**
           * Only present during development using @expo/cli.
           */
          hostUri?: string;
        })
      | null {
      const maybeManifest = getManifest(true);
      if (!maybeManifest) {
        return null;
      }

      // if running an embedded update, maybeManifest is a EmbeddedManifest which doesn't have
      // the expo config. Instead, the embedded expo-constants app.config should be used.
      if (ExpoUpdates && ExpoUpdates.isEmbeddedLaunch) {
        return rawAppConfig;
      }

      if (isExpoUpdatesManifest(maybeManifest)) {
        return maybeManifest.extra?.expoClient ?? null;
      } else if (isEmbeddedManifest(maybeManifest)) {
        return maybeManifest as any;
      }

      return null;
    },
    enumerable: true,
  },
  expoGoConfig: {
    get(): ExpoGoConfig | null {
      const maybeManifest = getManifest(true);
      if (!maybeManifest) {
        return null;
      }

      if (isExpoUpdatesManifest(maybeManifest)) {
        return maybeManifest.extra?.expoGo ?? null;
      } else if (isEmbeddedManifest(maybeManifest)) {
        return maybeManifest as any;
      }

      return null;
    },
    enumerable: true,
  },
  easConfig: {
    get(): EASConfig | null {
      const maybeManifest = getManifest(true);
      if (!maybeManifest) {
        return null;
      }

      if (isExpoUpdatesManifest(maybeManifest)) {
        return maybeManifest.extra?.eas ?? null;
      } else if (isEmbeddedManifest(maybeManifest)) {
        return maybeManifest as any;
      }

      return null;
    },
    enumerable: true,
  },
  __rawManifest_TEST: {
    get(): RawManifest | null {
      return rawManifest;
    },
    set(value: RawManifest | null) {
      rawManifest = value;
    },
    enumerable: false,
  },
});

function isEmbeddedManifest(manifest: RawManifest): manifest is EmbeddedManifest {
  return !isExpoUpdatesManifest(manifest);
}

function isExpoUpdatesManifest(manifest: RawManifest): manifest is ExpoUpdatesManifest {
  return 'metadata' in manifest;
}

function getManifest(suppressWarning = false): RawManifest | null {
  if (!rawManifest) {
    const invalidManifestType = rawManifest === null ? 'null' : 'undefined';
    if (
      nativeConstants.executionEnvironment === ExecutionEnvironment.Bare &&
      Platform.OS !== 'web'
    ) {
      if (!suppressWarning) {
        console.warn(
          `Constants.manifest is ${invalidManifestType} because the embedded app.config could not be read. Ensure that you have installed the expo-constants build scripts if you need to read from Constants.manifest.`
        );
      }
    } else if (
      nativeConstants.executionEnvironment === ExecutionEnvironment.StoreClient ||
      nativeConstants.executionEnvironment === ExecutionEnvironment.Standalone
    ) {
      // If we somehow get here, this is a truly exceptional state to be in.
      // Constants.manifest should *always* be defined in those contexts.
      throw new CodedError(
        'ERR_CONSTANTS_MANIFEST_UNAVAILABLE',
        `Constants.manifest is ${invalidManifestType}, must be an object.`
      );
    }
  }
  return rawManifest;
}

export default constants as Constants;