refactor: use useshouldbase64encode from @netlify/dev-utils (#7445)

* Refactor useShouldBase64Encode util from dev-utils

* Moved import to correct grouping

Author: keanu-a

src/lib/functions/server.ts

@@ -3,6 +3,7 @@ import { promises as fs } from 'fs'
 import type { IncomingHttpHeaders } from 'http'
 import path from 'path'
 
+import { shouldBase64Encode } from '@netlify/dev-utils'
 import express, { type Request, type RequestHandler } from 'express'
 import expressLogging from 'express-logging'
 import { jwtDecode } from 'jwt-decode'
@@ -29,7 +30,6 @@ import { createFormSubmissionHandler } from './form-submissions-handler.js'
 import { FunctionsRegistry } from './registry.js'
 import { handleScheduledFunction } from './scheduled.js'
 import { handleSynchronousFunction } from './synchronous.js'
-import { shouldBase64Encode } from './utils.js'
 
 type FunctionsSettings = Pick<ServerSettings, 'functions' | 'functionsPort'>
 
@@ -122,7 +122,7 @@ export const createHandler = function (options: GetFunctionsServerOptions): Requ
       return
     }
 
-    const isBase64Encoded = shouldBase64Encode(request.header('content-type'))
+    const isBase64Encoded = shouldBase64Encode(request.header('content-type') ?? '')
     let body
     if (hasBody(request)) {
       body = request.body.toString(isBase64Encoded ? 'base64' : 'utf8')

src/lib/functions/utils.ts

@@ -20,39 +20,4 @@ export const formatLambdaError = (err: Error | InvocationError): string =>
     `${'errorType' in err ? err.errorType : 'Error'}: ${'errorMessage' in err ? err.errorMessage : err.message}`,
   )
 
-// should be equivalent to https://github.com/netlify/proxy/blob/main/pkg/functions/request.go#L105
-const exceptionsList = new Set([
-  'application/csp-report',
-  'application/graphql',
-  'application/json',
-  'application/javascript',
-  'application/x-www-form-urlencoded',
-  'application/x-ndjson',
-  'application/xml',
-])
-
-export const shouldBase64Encode = function (contentType?: string): boolean {
-  if (!contentType) {
-    return true
-  }
-
-  const [contentTypeSegment] = contentType.split(';')
-  contentType = contentTypeSegment
-  contentType = contentType.toLowerCase()
-
-  if (contentType.startsWith('text/')) {
-    return false
-  }
-
-  if (contentType.endsWith('+json') || contentType.endsWith('+xml')) {
-    return false
-  }
-
-  if (exceptionsList.has(contentType)) {
-    return false
-  }
-
-  return true
-}
-
 export const styleFunctionName = (name: string): string => chalk.magenta(name)