exponential backoff bug fix

client/app/src/main/java/com/birdthedeveloper/prometheus/android/prometheus/android/exporter/worker/ExponentialBackoff.kt

@@ -1,10 +1,13 @@
 package com.birdthedeveloper.prometheus.android.prometheus.android.exporter.worker
 
+import android.util.Log
 import kotlinx.coroutines.CancellationException
 import kotlinx.coroutines.delay
 import kotlin.math.min
 import kotlin.math.pow
 
+private const val TAG : String = "EXPONENTIAL_BACKOFF"
+
 class ExponentialBackoff {
     companion object {
         private const val multiplier: Double = 2.0
@@ -26,12 +29,12 @@ class ExponentialBackoff {
                     function()
                     successfull = true
                 } catch (e: CancellationException) {
-                    break
+                    throw e
                 } catch (e: Exception) {
                     // check for suppressed exceptions
                     for (exception in e.suppressed) {
                         if (exception is CancellationException) {
-                            break
+                            throw exception
                         }
                     }
 
@@ -47,6 +50,8 @@ class ExponentialBackoff {
                         break
                     }
 
+                    Log.d(TAG, "Backoff with delay: $currentDelay seconds")
+
                     delay(currentDelay.toLong() * 1000)
                 }
             }

client/app/src/main/java/com/birdthedeveloper/prometheus/android/prometheus/android/exporter/worker/PromWorker.kt

@@ -48,7 +48,7 @@ class PromWorker(
         return writer.toString()
     }
 
-    private suspend fun countSuccessfulScrape() {
+    private fun countSuccessfulScrape() {
         Log.d(TAG, "Counting successful scrape")
         remoteWriteSender?.countSuccessfulScrape()
     }

client/app/src/main/java/com/birdthedeveloper/prometheus/android/prometheus/android/exporter/worker/PushProxClient.kt

@@ -112,11 +112,13 @@ class PushProxClient(private val pushProxConfig: PushProxConfig) {
 
     // Continuously poll from pushprox gateway
     private suspend fun doPoll(context: PushProxContext) {
+        Log.d(TAG, "Polling now")
         val response: HttpResponse = context.client.post(context.pollUrl) {
             setBody(context.fqdn)
         }
         val responseBody: String = response.body<String>()
         doPush(context, responseBody)
+        Log.d(TAG, "Polling finished")
     }
 
     // get value of HTTP header "Id" from response body

client/app/src/main/java/com/birdthedeveloper/prometheus/android/prometheus/android/exporter/worker/RemoteWriteSender.kt

@@ -6,12 +6,12 @@ import android.net.NetworkCapabilities
 import android.util.Log
 import androidx.work.impl.utils.getActiveNetworkCompat
 import io.ktor.client.HttpClient
-import io.ktor.client.call.body
 import io.ktor.client.request.header
 import io.ktor.client.request.headers
 import io.ktor.client.request.post
 import io.ktor.client.request.setBody
 import io.ktor.http.HttpHeaders
+import io.ktor.http.HttpStatusCode
 import io.prometheus.client.CollectorRegistry
 import kotlinx.coroutines.NonCancellable
 import kotlinx.coroutines.channels.BufferOverflow
@@ -109,12 +109,19 @@ class RemoteWriteSender(private val config: RemoteWriteConfiguration) {
 
     private suspend fun sendAll() {
         Log.d(TAG, "sendAll")
-        scrapesAreBeingSent = true
-        while (!storage.isEmpty()) {
-            val body = storage.getScrapedSamplesCompressedProtobuf(config.maxSamplesPerExport)
-            ExponentialBackoff.runWithBackoff({ sendRequestToRemoteWrite(body) }, {}, false)
+        if (!scrapesAreBeingSent) {
+            scrapesAreBeingSent = true
+
+            while (!storage.isEmpty()) {
+                val body = storage.getScrapedSamplesCompressedProtobuf(config.maxSamplesPerExport)
+                Log.d(TAG, "Exponential backoff to export remote write started")
+                ExponentialBackoff.runWithBackoff({
+                    sendRequestToRemoteWrite(body, config.maxSamplesPerExport)
+                }, {}, false)
+                Log.d(TAG, "Exponential backoff to export remote write finish")
+            }
+            lastTimeRemoteWriteSent = System.currentTimeMillis()
         }
-        lastTimeRemoteWriteSent = System.currentTimeMillis()
     }
 
     private fun deviceHasInternet(): Boolean {
@@ -193,7 +200,7 @@ class RemoteWriteSender(private val config: RemoteWriteConfiguration) {
         lastTimeRingBuffer.setLastTime(System.currentTimeMillis())
     }
 
-    private suspend fun sendRequestToRemoteWrite(body: ByteArray) {
+    private suspend fun sendRequestToRemoteWrite(body: ByteArray, numOfMetricScrapes : Int) {
         Log.d(TAG, "Exporting remote write to prometheus now")
         val response = client.post(config.remoteWriteEndpoint) {
             setBody(body)
@@ -206,5 +213,10 @@ class RemoteWriteSender(private val config: RemoteWriteConfiguration) {
         }
 
         Log.d(TAG, "Response status: ${response.status}")
+
+        if (response.status == HttpStatusCode.NoContent){
+            // this export was successful
+            storage.removeNumberOfScrapedSamples(numOfMetricScrapes)
+        }
     }
 }