feat: Support exporter metadata in Android provider

openfeature/providers/kotlin-provider/gofeatureflag-kotlin-provider/src/main/java/org/gofeatureflag/openfeature/bean/GoFeatureFlagOptions.kt

@@ -47,6 +47,15 @@ data class GoFeatureFlagOptions(
      * when calling the evaluation API.
      * default: 1000 ms
      */
-    val flushIntervalMs: Long = 300000
+    val flushIntervalMs: Long = 300000,
+
+    /**
+     *  (optional) exporter metadata is a set of key-value that will be added to the metadata when calling the
+     *  exporter API. All those informations will be added to the event produce by the exporter.
+     *
+     * ‼️Important: If you are using a GO Feature Flag relay proxy before version v1.41.0, the information
+     * of this field will not be added to your feature events.
+     */
+    val exporterMetadata: Map<String, Any> = emptyMap(),
 )
 

openfeature/providers/kotlin-provider/gofeatureflag-kotlin-provider/src/main/java/org/gofeatureflag/openfeature/controller/GoFeatureFlagApi.kt

@@ -52,7 +52,11 @@ class GoFeatureFlagApi(private val options: GoFeatureFlagOptions) {
         }
 
         val mediaType = "application/json".toMediaTypeOrNull()
-        val requestBody = gson.toJson(Events(events)).toRequestBody(mediaType)
+
+        val metadata = options.exporterMetadata.toMutableMap()
+        metadata["provider"] = "android"
+        metadata["openfeature"] = true
+        val requestBody = gson.toJson(Events(events, metadata)).toRequestBody(mediaType)
         val reqBuilder = okhttp3.Request.Builder()
             .url(urlBuilder.build())
             .post(requestBody)

openfeature/providers/kotlin-provider/gofeatureflag-kotlin-provider/src/main/java/org/gofeatureflag/openfeature/hook/Events.kt

@@ -3,5 +3,5 @@ package org.gofeatureflag.openfeature.hook
 
 data class Events(
     val events: List<Event>?,
-    val meta: Map<String, String> = mapOf("provider" to "android", "openfeature" to "true")
+    val meta: Map<String, Any> = emptyMap()
 )

openfeature/providers/kotlin-provider/gofeatureflag-kotlin-provider/src/test/java/org/gofeatureflag/openfeature/GoFeatureFlagProviderTest.kt

@@ -176,4 +176,59 @@ class GoFeatureFlagProviderTest {
         val got2 = Gson().fromJson(recordedRequest2.body.readUtf8(), Events::class.java)
         assertEquals(3, got2.events?.size)
     }
+
+    @Test
+    fun `should call the hook and send metadata`() {
+        val jsonFilePath =
+            javaClass.classLoader?.getResource("org.gofeatureflag.openfeature.ofrep/valid_api_response.json")?.file
+        val jsonString = String(Files.readAllBytes(Paths.get(jsonFilePath)))
+        mockWebServer!!.enqueue(MockResponse().setBody(jsonString).setResponseCode(200))
+        mockWebServer!!.enqueue(MockResponse().setBody("{}").setResponseCode(200))
+        mockWebServer!!.enqueue(MockResponse().setBody("{}").setResponseCode(200))
+        val options =
+            GoFeatureFlagOptions(
+                endpoint = mockWebServer!!.url("/").toString(),
+                flushIntervalMs = 100,
+                pollingIntervalInMillis = 10000,
+                exporterMetadata = mapOf("device" to "Pixel 4", "appVersion" to "1.0.0")
+            )
+
+        val provider = GoFeatureFlagProvider(options)
+        val ctx = ImmutableContext(targetingKey = "123")
+        runBlocking {
+            OpenFeatureAPI.setProviderAndWait(
+                provider = provider,
+                dispatcher = Dispatchers.IO,
+                initialContext = ctx
+            )
+        }
+
+        val client = OpenFeatureAPI.getClient()
+        client.getStringValue("title-flag", "default")
+        client.getStringValue("title-flag", "default")
+        client.getStringValue("title-flag", "default")
+        client.getStringValue("title-flag", "default")
+        client.getStringValue("title-flag", "default")
+        client.getStringValue("title-flag", "default")
+        Thread.sleep(1000)
+        client.getStringValue("title-flag", "default")
+        client.getStringValue("title-flag", "default")
+        client.getStringValue("title-flag", "default")
+        Thread.sleep(1000)
+        mockWebServer!!.takeRequest()
+        val recordedRequest: RecordedRequest = mockWebServer!!.takeRequest()
+        val got = Gson().fromJson(recordedRequest.body.readUtf8(), Events::class.java)
+        assertEquals(6, got.events?.size)
+        assertEquals("Pixel 4", got.meta["device"])
+        assertEquals("1.0.0", got.meta["appVersion"])
+        assertEquals("android", got.meta["provider"])
+        assertEquals(true, got.meta["openfeature"])
+        val recordedRequest2: RecordedRequest = mockWebServer!!.takeRequest()
+        val got2 = Gson().fromJson(recordedRequest2.body.readUtf8(), Events::class.java)
+        assertEquals(3, got2.events?.size)
+        assertEquals("Pixel 4", got2.meta["device"])
+        assertEquals("1.0.0", got2.meta["appVersion"])
+        assertEquals("android", got2.meta["provider"])
+        assertEquals(true, got2.meta["openfeature"])
+    }
 }

openfeature/providers/kotlin-provider/gofeatureflag-kotlin-provider/src/test/java/org/gofeatureflag/openfeature/controller/GoFeatureFlagApiTest.kt

@@ -140,4 +140,24 @@ class GoFeatureFlagApiTest {
         val got = recordedRequest.body.readUtf8()
         JSONAssert.assertEquals(want, got, false)
     }
+
+    @Test
+    fun `should have a valid body request when using exporter metadata`(): Unit = runBlocking {
+        mockWebServer!!.enqueue(MockResponse().setBody("{}").setResponseCode(200))
+        val api =
+            GoFeatureFlagApi(
+                GoFeatureFlagOptions(
+                    endpoint = mockWebServer!!.url("/").toString(),
+                    apiKey = "my-api-key",
+                    exporterMetadata = mapOf("appVersion" to "1.0.0", "device" to "Pixel 4")
+                )
+            )
+        api.postEventsToDataCollector(defaultEventList)
+        val recordedRequest: RecordedRequest = mockWebServer!!.takeRequest()
+        val jsonFilePath =
+            javaClass.classLoader?.getResource("org/gofeatureflag/openfeature/hook/valid_result_metadata.json")?.file
+        val want = File(jsonFilePath.toString()).readText(Charsets.UTF_8)
+        val got = recordedRequest.body.readUtf8()
+        JSONAssert.assertEquals(want, got, false)
+    }
 }

openfeature/providers/kotlin-provider/gofeatureflag-kotlin-provider/src/test/resources/org/gofeatureflag/openfeature/hook/valid_result.json

@@ -13,6 +13,6 @@
   ],
   "meta": {
     "provider": "android",
-    "openfeature": "true"
+    "openfeature": true
   }
 }

openfeature/providers/kotlin-provider/gofeatureflag-kotlin-provider/src/test/resources/org/gofeatureflag/openfeature/hook/valid_result_metadata.json

@@ -0,0 +1,20 @@
+{
+  "events": [
+    {
+      "contextKind": "contextKind",
+      "creationDate": 1721650841,
+      "key": "flag-1",
+      "kind": "feature",
+      "userKey": "981f2662-1fb4-4732-ac6d-8399d9205aa9",
+      "value": true,
+      "default": false,
+      "variation": "enabled"
+    }
+  ],
+  "meta": {
+    "provider": "android",
+    "openfeature": true,
+    "appVersion": "1.0.0",
+    "device": "Pixel 4"
+  }
+}