feat: add env var to disable firebase v2 fallback

Author: pastelsky

cache-service/middlewares/exports-size.middleware.js

@@ -42,7 +42,11 @@ async function getPackageResult({ name, version, readKey }) {
   }
 
   // If reading from default v3 and not found, fall back to "exports" (v2)
-  if (targetReadKey === 'exports-v3' && !readKey) {
+  if (
+    targetReadKey === 'exports-v3' &&
+    !readKey &&
+    !process.env.DISABLE_FIREBASE_V2_FALLBACK
+  ) {
     const fallbackResult = await getPackageResultFromKey('exports', {
       name,
       version,

cache-service/middlewares/package-size.middleware.js

@@ -42,7 +42,11 @@ async function getPackageResult({ name, version, readKey }) {
   }
 
   // If reading from default v3 and not found, fall back to v2
-  if (targetReadKey === 'modules-v3' && !readKey) {
+  if (
+    targetReadKey === 'modules-v3' &&
+    !readKey &&
+    !process.env.DISABLE_FIREBASE_V2_FALLBACK
+  ) {
     const fallbackResult = await getPackageResultFromKey('modules-v2', {
       name,
       version,

utils/firebase.utils.js

@@ -85,7 +85,10 @@ class FirebaseUtils {
         return result
       }
       // Fallback to v2 if reading from v3
-      if (FIREBASE_READ_KEY === 'modules-v3') {
+      if (
+        FIREBASE_READ_KEY === 'modules-v3' &&
+        !process.env.DISABLE_FIREBASE_V2_FALLBACK
+      ) {
         const fallback = await getHistoryFromKey('modules-v2')
         if (fallback) {
           debug('package history from modules-v2 (fallback)')