[eas-cli] Pass _expo/.routes.json for SSG exports as routes.json to Hosting deployments (#3211)

* Derive `routes.json` payload from static export `_expo/.routes.json`

* Add CHANGELOG entry

Author: kitten

CHANGELOG.md

@@ -8,6 +8,8 @@ This is the log of notable changes to EAS CLI and related packages.
 
 ### 🎉 New features
 
+- Support `_expo/.routes.json` metadata file exported by `@expo/cli` for headers configuration on static deployments ([#3211](https://github.com/expo/eas-cli/pull/3211) by [@kitten](https://github.com/kitten))
+
 ### 🐛 Bug fixes
 
 ### 🧹 Chores

packages/eas-cli/src/commands/deploy/index.ts

@@ -138,6 +138,7 @@ export default class WorkerDeploy extends EasCommand {
     logExportedProjectInfo(projectDist);
 
     async function* emitWorkerTarballAsync(params: {
+      routesConfig: WorkerAssets.RoutesConfigEntry | null;
       assetMap: WorkerAssets.AssetMap;
       manifest: WorkerAssets.Manifest;
     }): AsyncGenerator<WorkerAssets.FileEntry> {
@@ -148,6 +149,8 @@ export default class WorkerDeploy extends EasCommand {
         for await (const workerFile of workerFiles) {
           yield [`server/${workerFile.normalizedPath}`, workerFile.data];
         }
+      } else if (projectDist.type === 'static' && params.routesConfig) {
+        yield ['routes.json', JSON.stringify(params.routesConfig)];
       }
     }
 
@@ -284,12 +287,13 @@ export default class WorkerDeploy extends EasCommand {
             manifestResult.conflictingVariableNames.join(' ')
         );
       }
-      assetFiles = await WorkerAssets.collectAssetsAsync(
-        projectDist.type === 'server' ? projectDist.clientPath : projectDist.path,
-        { maxFileSize: MAX_UPLOAD_SIZE }
-      );
+      const assetPath = projectDist.type === 'server' ? projectDist.clientPath : projectDist.path;
+      assetFiles = await WorkerAssets.collectAssetsAsync(assetPath, {
+        maxFileSize: MAX_UPLOAD_SIZE,
+      });
       tarPath = await WorkerAssets.packFilesIterableAsync(
         emitWorkerTarballAsync({
+          routesConfig: await WorkerAssets.getRoutesConfigAsync(assetPath),
           assetMap: WorkerAssets.assetsToAssetsMap(assetFiles),
           manifest: manifestResult.manifest,
         })

packages/eas-cli/src/worker/assets.ts

@@ -12,6 +12,8 @@ import { EnvironmentVariableEnvironment } from '../build/utils/environment';
 import { ExpoGraphqlClient } from '../commandUtils/context/contextUtils/createGraphqlClient';
 import { EnvironmentVariablesQuery } from '../graphql/queries/EnvironmentVariablesQuery';
 
+const EXPO_ROUTES_PATHS = new Set(['_expo/routes.json', '_expo/.routes.json', '.expo-routes.json']);
+
 /** Returns whether a file or folder is ignored */
 function isIgnoredName(name: string): boolean {
   switch (name) {
@@ -114,6 +116,8 @@ export async function collectAssetsAsync(
         throw new Error(
           `Upload of "${file.normalizedPath}" aborted: File size is greater than the upload limit (>500MB)`
         );
+      } else if (EXPO_ROUTES_PATHS.has(file.normalizedPath)) {
+        continue;
       }
       const sha512$ = computeSha512HashAsync(file.path);
       const contentType$ = determineMimeTypeAsync(file.path);
@@ -129,6 +133,31 @@ export async function collectAssetsAsync(
   return assets;
 }
 
+export interface RoutesConfigEntry {
+  headers?: Record<string, unknown>;
+  redirects?: Record<string, unknown>[];
+}
+
+export async function getRoutesConfigAsync(
+  assetPath: string | undefined
+): Promise<RoutesConfigEntry | null> {
+  if (assetPath) {
+    for (const candidatePath of EXPO_ROUTES_PATHS) {
+      const targetPath = path.resolve(assetPath, candidatePath);
+      let json: unknown;
+      try {
+        json = JSON.parse(await fs.promises.readFile(targetPath, 'utf8'));
+      } catch {
+        continue;
+      }
+      if (typeof json === 'object' && json) {
+        return json as RoutesConfigEntry;
+      }
+    }
+  }
+  return null;
+}
+
 /** Mapping of normalized file paths to a SHA512 hash */
 export type AssetMap = Record<
   string,