Callback to receive raw response body from featurevisor data request (#26)

Author: klauudiaa

src/main/kotlin/com/featurevisor/sdk/Instance+Fetch.kt

@@ -13,18 +13,20 @@ import java.lang.IllegalArgumentException
 internal fun FeaturevisorInstance.fetchDatafileContent(
     url: String,
     handleDatafileFetch: DatafileFetchHandler? = null,
+    rawResponseReady: (ResponseBody) -> Unit,
     completion: (Result<DatafileContent>) -> Unit,
 ) {
     handleDatafileFetch?.let { handleFetch ->
         val result = handleFetch(url)
         completion(result)
     } ?: run {
-        fetchDatafileContentFromUrl(url, completion)
+        fetchDatafileContentFromUrl(url, rawResponseReady, completion)
     }
 }
 
 private fun fetchDatafileContentFromUrl(
     url: String,
+    rawResponseReady: (ResponseBody) -> Unit,
     completion: (Result<DatafileContent>) -> Unit,
 ) {
     try {
@@ -34,7 +36,7 @@ private fun fetchDatafileContentFromUrl(
             .addHeader("Content-Type", "application/json")
             .build()
 
-        fetch(request, completion)
+        fetch(request, rawResponseReady, completion)
     } catch (throwable: IllegalArgumentException) {
         completion(Result.failure(FeaturevisorError.InvalidUrl(url)))
     }
@@ -43,13 +45,15 @@ private fun fetchDatafileContentFromUrl(
 const val BODY_BYTE_COUNT = 1000000L
 private inline fun fetch(
     request: Request,
+    crossinline rawResponseReady: (ResponseBody) -> Unit,
     crossinline completion: (Result<DatafileContent>) -> Unit,
 ) {
     val client = OkHttpClient()
     val call = client.newCall(request)
     call.enqueue(object : Callback {
         override fun onResponse(call: Call, response: Response) {
             val responseBody = response.peekBody(BODY_BYTE_COUNT)
+            rawResponseReady(responseBody)
             if (response.isSuccessful) {
                 val json = Json {
                     ignoreUnknownKeys = true

src/main/kotlin/com/featurevisor/sdk/Instance+Refresh.kt

@@ -42,6 +42,7 @@ private fun FeaturevisorInstance.refresh() {
             fetchDatafileContent(
                 datafileUrl,
                 handleDatafileFetch,
+                rawResponseReady,
             ) { result ->
 
                 if (result.isSuccess) {

src/main/kotlin/com/featurevisor/sdk/Instance.kt

@@ -9,6 +9,7 @@ import com.featurevisor.types.EventName.*
 import kotlinx.coroutines.Job
 import kotlinx.serialization.decodeFromString
 import kotlinx.serialization.json.Json
+import okhttp3.ResponseBody
 
 typealias ConfigureBucketKey = (Feature, Context, BucketKey) -> BucketKey
 typealias ConfigureBucketValue = (Feature, Context, BucketValue) -> BucketValue
@@ -56,6 +57,7 @@ class FeaturevisorInstance private constructor(options: InstanceOptions) {
     internal var configureBucketKey = options.configureBucketKey
     internal var configureBucketValue = options.configureBucketValue
     internal var refreshJob: Job? = null
+    internal var rawResponseReady: (ResponseBody) -> Unit = options.rawResponseReady
 
     init {
         with(options) {
@@ -100,7 +102,7 @@ class FeaturevisorInstance private constructor(options: InstanceOptions) {
 
                 datafileUrl != null -> {
                     datafileReader = DatafileReader(options.datafile?: emptyDatafile)
-                    fetchDatafileContent(datafileUrl, handleDatafileFetch) { result ->
+                    fetchDatafileContent(datafileUrl, handleDatafileFetch, rawResponseReady) { result ->
                         if (result.isSuccess) {
                             datafileReader = DatafileReader(result.getOrThrow())
                             statuses.ready = true

src/main/kotlin/com/featurevisor/sdk/InstanceOptions.kt

@@ -3,6 +3,7 @@ package com.featurevisor.sdk
 import com.featurevisor.types.DatafileContent
 import com.featurevisor.types.InitialFeatures
 import com.featurevisor.types.StickyFeatures
+import okhttp3.ResponseBody
 
 typealias Listener = (Array<out Any>) -> Unit
 
@@ -23,6 +24,7 @@ data class InstanceOptions(
     val onError: Listener? = null,
     val refreshInterval: Long? = null, // seconds
     val stickyFeatures: StickyFeatures? = null,
+    val rawResponseReady: (ResponseBody) -> Unit = {},
 ) {
     companion object {
         private const val defaultBucketKeySeparator = "."