chore: parallelize config fetch

sdk/nextjs/src/server/bucketing.ts

@@ -88,21 +88,14 @@ class CDNConfigSource extends ConfigSource {
     }
 }
 
-/**
- * Retrieve the config from CDN for the current request's SDK Key. This data will often be cached
- * Compute the bucketed config for the current request's user using that data, with local bucketing library
- * Cache the bucketed config for this request so that repeated calls to this function are memoized
- */
-export const getBucketedConfig = async (
+export const getConfigFromSource = async (
     sdkKey: string,
     clientSDKKey: string,
-    user: DevCycleUser,
     options: DevCycleNextOptions,
-    userAgent?: string,
-): Promise<BucketedConfigWithAdditionalFields> => {
+): Promise<{ config: ConfigBody; lastModified: string | null }> => {
     const cdnConfigSource = new CDNConfigSource(clientSDKKey)
-
     const configSource = options.configSource ?? cdnConfigSource
+
     const { config, lastModified } = await configSource.getConfig(
         sdkKey,
         'bootstrap',
@@ -111,6 +104,20 @@ export const getBucketedConfig = async (
         true,
     )
 
+    return { config, lastModified }
+}
+
+/**
+ * Compute the bucketed config for the current request's user using raw config data, with local bucketing library
+ * Cache the bucketed config for this request so that repeated calls to this function are memoized
+ */
+export const getBucketedConfig = async (
+    config: ConfigBody,
+    lastModified: string | null,
+    user: DevCycleUser,
+    options: DevCycleNextOptions,
+    userAgent?: string,
+): Promise<BucketedConfigWithAdditionalFields> => {
     const { bucketedConfig } = await generateBucketedConfigCached(
         !!options.enableObfuscation,
         user,

sdk/nextjs/src/server/initialize.ts

@@ -3,7 +3,7 @@ import { getClient, setClient } from './requestContext'
 import { getUserAgent } from './userAgent'
 import { DevCycleNextOptions, DevCycleServerData } from '../common/types'
 import { cache } from 'react'
-import { getBucketedConfig } from './bucketing'
+import { getBucketedConfig, getConfigFromSource } from './bucketing'
 
 const jsClientOptions = {
     // pass next object to enable "next" mode in JS SDK
@@ -29,11 +29,12 @@ export const initialize = async (
     userGetter: () => DevCycleUser | Promise<DevCycleUser>,
     options: DevCycleNextOptions = {},
 ): Promise<DevCycleServerData> => {
-    // TODO moving this call to inside `getBucketedConfig` appears to cause static build issues from reading headers
-    // Might be a bug in Next, if moving this make sure to verify you can `yarn next build` the e2e app router app
-    const userAgent = await getUserAgent(options)
+    const [userAgent, user, configData] = await Promise.all([
+        getUserAgent(options),
+        cachedUserGetter(userGetter),
+        getConfigFromSource(sdkKey, clientSDKKey, options),
+    ])
 
-    const user = await cachedUserGetter(userGetter)
     if (!user || typeof user.user_id !== 'string') {
         throw new Error('DevCycle user getter must return a user')
     }
@@ -53,8 +54,8 @@ export const initialize = async (
     let config = null
     try {
         config = await getBucketedConfig(
-            sdkKey,
-            clientSDKKey,
+            configData.config,
+            configData.lastModified,
             user,
             options,
             userAgent,