feat: enable passing extra configurable headers to postgrest client. (#191)

Author: jianhan

.env.sample

@@ -23,4 +23,7 @@ LOGFLARE_ENABLED=false
 LOGFLARE_API_KEY=api_key
 LOGFLARE_SOURCE_TOKEN=source_token
 
-IMGPROXY_URL=http://localhost:50020
+IMGPROXY_URL=http://localhost:50020
+
+# specify the extra headers will be persisted and passed into Postgrest client, for instance, "x-foo,x-bar"
+POSTGREST_FORWARD_HEADERS=

Dockerfile

@@ -15,7 +15,7 @@ FROM node:18-alpine
 RUN npm install -g pm2
 WORKDIR /app
 COPY migrations migrations
-COPY ecosystem.config.js package.json .
+COPY ecosystem.config.js package.json ./
 COPY --from=0 /app/node_modules node_modules
 COPY --from=1 /app/dist dist
 EXPOSE 5000

src/plugins/postgrest.ts

@@ -12,6 +12,29 @@ declare module 'fastify' {
   }
 }
 
+function generatePostgrestForwardHeaders(
+  forwardHeaders: string | undefined,
+  request: FastifyRequest,
+  ignore: string[] = []
+): Record<string, string> {
+  if (!forwardHeaders) {
+    return {}
+  }
+
+  return forwardHeaders
+    .split(',')
+    .map((headerName) => headerName.trim())
+    .filter((headerName) => headerName in request.headers && !ignore.includes(headerName))
+    .reduce((extraHeaders, headerName) => {
+      const headerValue = request.headers[headerName]
+      if (typeof headerValue !== 'string') {
+        throw new Error(`header ${headerName} must be string`)
+      }
+      extraHeaders[headerName] = headerValue
+      return extraHeaders
+    }, {} as Record<string, string>)
+}
+
 async function getPostgrestClient(request: FastifyRequest, jwt: string): Promise<PostgrestClient> {
   const {
     anonKey,
@@ -20,6 +43,7 @@ async function getPostgrestClient(request: FastifyRequest, jwt: string): Promise
     postgrestURLScheme,
     postgrestURLSuffix,
     xForwardedHostRegExp,
+    postgrestForwardHeaders,
   } = getConfig()
 
   let url = postgrestURL
@@ -35,14 +59,22 @@ async function getPostgrestClient(request: FastifyRequest, jwt: string): Promise
     url = `${postgrestURLScheme}://${xForwardedHost}${postgrestURLSuffix}`
     apiKey = await getAnonKey(request.tenantId)
   }
-  const postgrest = new PostgrestClient(url, {
+
+  const pgClientHeaders = {
+    apiKey,
+    Authorization: `Bearer ${jwt}`,
+  }
+  return new PostgrestClient(url, {
     headers: {
-      apiKey,
-      Authorization: `Bearer ${jwt}`,
+      ...pgClientHeaders,
+      ...generatePostgrestForwardHeaders(
+        postgrestForwardHeaders,
+        request,
+        Object.keys(pgClientHeaders)
+      ), // extra forwarded headers
     },
     schema: 'storage',
   })
-  return postgrest
 }
 
 export const postgrest = fastifyPlugin(async (fastify) => {

src/test/postgrest-forward-headers.test.ts

@@ -0,0 +1,58 @@
+'use strict'
+import app from '../app'
+import dotenv from 'dotenv'
+import { PostgrestClient } from '@supabase/postgrest-js'
+jest.mock('@supabase/postgrest-js')
+
+dotenv.config({ path: '.env.test' })
+
+beforeEach(() => {
+  jest.clearAllMocks()
+})
+
+describe('Extra headers should be forwarded to postgrest client', () => {
+  test('it should only preserve the headers that are defined in environment variable', async () => {
+    process.env.POSTGREST_FORWARD_HEADERS = 'x-foo, x-bar'
+    const extraHeaders = { 'x-foo': 1, 'x-bar': 2, 'x-none-exist': 3 }
+    await app().inject({
+      method: 'GET',
+      url: `/bucket`,
+      headers: {
+        authorization: `Bearer ${process.env.AUTHENTICATED_KEY}`,
+        ...extraHeaders,
+      },
+    })
+
+    expect(PostgrestClient).toBeCalledWith(process.env.POSTGREST_URL, {
+      headers: {
+        Authorization: `Bearer ${process.env.AUTHENTICATED_KEY}`,
+        apiKey: process.env.ANON_KEY,
+        'x-foo': '1',
+        'x-bar': '2',
+      },
+      schema: 'storage',
+    })
+  })
+
+  test('it should not preserve any extra headers when environment variable is not set', async () => {
+    delete process.env.POSTGREST_FORWARD_HEADERS
+    const extraHeaders = { 'x-foo': 1, 'x-bar': 2 }
+
+    await app().inject({
+      method: 'GET',
+      url: `/bucket`,
+      headers: {
+        authorization: `Bearer ${process.env.AUTHENTICATED_KEY}`,
+        ...extraHeaders,
+      },
+    })
+
+    expect(PostgrestClient).toBeCalledWith(process.env.POSTGREST_URL, {
+      headers: {
+        Authorization: `Bearer ${process.env.AUTHENTICATED_KEY}`,
+        apiKey: process.env.ANON_KEY,
+      },
+      schema: 'storage',
+    })
+  })
+})

src/utils/config.ts

@@ -34,6 +34,7 @@ type StorageConfigType = {
       max: number
     }
   }
+  postgrestForwardHeaders?: string
 }
 
 function getOptionalConfigFromEnv(key: string): string | undefined {
@@ -93,5 +94,6 @@ export function getConfig(): StorageConfigType {
         max: parseInt(getOptionalConfigFromEnv('IMG_LIMITS_MAX_SIZE') || '5000', 10),
       },
     },
+    postgrestForwardHeaders: getOptionalConfigFromEnv('POSTGREST_FORWARD_HEADERS'),
   }
 }