Add custom headers to HttpsCallableReference

Author: svenjacobs

firebase-functions/src/androidTest/backend/functions/index.js

@@ -122,3 +122,7 @@ exports.timeoutTest = functions.https.onRequest((request, response) => {
   // Wait for longer than 500ms.
   setTimeout(() => response.send({data: true}), 500);
 });
+
+exports.headersTest = functions.https.onRequest((request, response) => {
+  response.status(200).send({data: request.headers});
+});

firebase-functions/src/androidTest/java/com/google/firebase/functions/CallTests.kt

@@ -90,4 +90,18 @@ class CallTests {
 
     assertThat(actual).isNull()
   }
+
+  @Test
+  fun testCustomHeaders() {
+    val functions = Firebase.functions(app)
+    val function = functions.getHttpsCallable("headersTest")
+      .addHeader("Header1", "value1")
+      .addHeader("Header2", "value2")
+      .addHeader("Header1", "value3")
+    val actual = Tasks.await(function.call()).getData() as? Map<*, *>
+
+    assertThat(actual).isNotNull()
+    assertThat(actual?.get("Header1")).isEqualTo("value3")
+    assertThat(actual?.get("Header2")).isEqualTo("value2")
+  }
 }

firebase-functions/src/main/java/com/google/firebase/functions/FirebaseFunctions.kt

@@ -38,6 +38,7 @@ import java.util.concurrent.Executor
 import javax.inject.Named
 import okhttp3.Call
 import okhttp3.Callback
+import okhttp3.Headers
 import okhttp3.MediaType
 import okhttp3.OkHttpClient
 import okhttp3.Request
@@ -174,7 +175,8 @@ internal constructor(
   internal fun call(
     name: String,
     data: Any?,
-    options: HttpsCallOptions
+    options: HttpsCallOptions,
+    headers: Map<String, String>,
   ): Task<HttpsCallableResult> {
     return providerInstalled.task
       .continueWithTask(executor) { contextProvider.getContext(options.limitedUseAppCheckTokens) }
@@ -184,7 +186,7 @@ internal constructor(
         }
         val context = task.result
         val url = getURL(name)
-        call(url, data, context, options)
+        call(url, data, context, options, headers)
       }
   }
 
@@ -195,15 +197,20 @@ internal constructor(
    * @param data Parameters to pass to the function. Can be anything encodable as JSON.
    * @return A Task that will be completed when the request is complete.
    */
-  internal fun call(url: URL, data: Any?, options: HttpsCallOptions): Task<HttpsCallableResult> {
+  internal fun call(
+    url: URL,
+    data: Any?,
+    options: HttpsCallOptions,
+    headers: Map<String, String>,
+  ): Task<HttpsCallableResult> {
     return providerInstalled.task
       .continueWithTask(executor) { contextProvider.getContext(options.limitedUseAppCheckTokens) }
       .continueWithTask(executor) { task: Task<HttpsCallableContext?> ->
         if (!task.isSuccessful) {
           return@continueWithTask Tasks.forException<HttpsCallableResult>(task.exception!!)
         }
         val context = task.result
-        call(url, data, context, options)
+        call(url, data, context, options, headers)
       }
   }
 
@@ -219,7 +226,8 @@ internal constructor(
     url: URL,
     data: Any?,
     context: HttpsCallableContext?,
-    options: HttpsCallOptions
+    options: HttpsCallOptions,
+    headers: Map<String, String>,
   ): Task<HttpsCallableResult?> {
     Preconditions.checkNotNull(url, "url cannot be null")
     val body: MutableMap<String?, Any?> = HashMap()
@@ -228,7 +236,9 @@ internal constructor(
     val bodyJSON = JSONObject(body)
     val contentType = MediaType.parse("application/json")
     val requestBody = RequestBody.create(contentType, bodyJSON.toString())
-    var request = Request.Builder().url(url).post(requestBody)
+    // Add custom headers first so that internal headers cannot be overwritten
+    val customHeaders = Headers.of(headers)
+    var request = Request.Builder().url(url).post(requestBody).headers(customHeaders)
     if (context!!.authToken != null) {
       request = request.header("Authorization", "Bearer " + context.authToken)
     }

firebase-functions/src/main/java/com/google/firebase/functions/HttpsCallableReference.kt

@@ -34,16 +34,33 @@ public class HttpsCallableReference {
   // Options for how to do the HTTPS call.
   @VisibleForTesting public val options: HttpsCallOptions
 
+  private val headers: MutableMap<String, String>
+
+  /** Creates a new reference with the given options. */
+  internal constructor(
+    functionsClient: FirebaseFunctions,
+    name: String?,
+    options: HttpsCallOptions,
+    headers: MutableMap<String, String>,
+  ) {
+    this.functionsClient = functionsClient
+    this.name = name
+    url = null
+    this.options = options
+    this.headers = headers
+  }
+
   /** Creates a new reference with the given options. */
   internal constructor(
     functionsClient: FirebaseFunctions,
     name: String?,
-    options: HttpsCallOptions
+    options: HttpsCallOptions,
   ) {
     this.functionsClient = functionsClient
     this.name = name
     url = null
     this.options = options
+    this.headers = mutableMapOf()
   }
 
   /** Creates a new reference with the given options. */
@@ -52,6 +69,7 @@ public class HttpsCallableReference {
     name = null
     this.url = url
     this.options = options
+    this.headers = mutableMapOf()
   }
 
   /**
@@ -97,9 +115,9 @@ public class HttpsCallableReference {
    */
   public fun call(data: Any?): Task<HttpsCallableResult> {
     return if (name != null) {
-      functionsClient.call(name, data, options)
+      functionsClient.call(name, data, options, headers)
     } else {
-      functionsClient.call(url!!, data, options)
+      functionsClient.call(url!!, data, options, headers)
     }
   }
 
@@ -119,9 +137,9 @@ public class HttpsCallableReference {
    */
   public fun call(): Task<HttpsCallableResult> {
     return if (name != null) {
-      functionsClient.call(name, null, options)
+      functionsClient.call(name, null, options, headers)
     } else {
-      functionsClient.call(url!!, null, options)
+      functionsClient.call(url!!, null, options, headers)
     }
   }
 
@@ -150,8 +168,21 @@ public class HttpsCallableReference {
    * @param units The units for the specified timeout.
    */
   public fun withTimeout(timeout: Long, units: TimeUnit): HttpsCallableReference {
-    val other = HttpsCallableReference(functionsClient, name, options)
+    val other = HttpsCallableReference(functionsClient, name, options, headers)
     other.setTimeout(timeout, units)
     return other
   }
+
+  /**
+   * Adds an HTTP header for calls from this instance of Functions.
+   *
+   * Note that an existing header with the same name will be overwritten.
+   *
+   * @param name Name of HTTP header
+   * @param value Value of HTTP header
+   */
+  public fun addHeader(name: String, value: String): HttpsCallableReference {
+    headers[name] = value
+    return this
+  }
 }