pushprox works

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

@@ -1,42 +1,28 @@
 package com.birdthedeveloper.prometheus.android.prometheus.android.exporter
 
-import android.preference.PreferenceActivity.Header
 import android.util.Log
 import io.github.reugn.kotlin.backoff.StrategyBackoff
 import io.github.reugn.kotlin.backoff.strategy.ExponentialStrategy
 import io.ktor.client.HttpClient
 import io.ktor.client.call.body
 import io.ktor.client.engine.cio.CIO
-import io.ktor.client.request.HttpRequestBuilder
-import io.ktor.client.request.get
-import io.ktor.client.request.header
 import io.ktor.client.request.post
 import io.ktor.client.request.request
 import io.ktor.client.request.setBody
 import io.ktor.client.statement.HttpResponse
-import io.ktor.http.HttpHeaders
 import io.ktor.http.HttpMethod
-import io.ktor.http.URLBuilder
-import io.ktor.http.Url
-import io.ktor.http.maxAge
 import io.prometheus.client.CollectorRegistry
 import io.prometheus.client.Counter
-import kotlinx.coroutines.Deferred
 import kotlinx.coroutines.GlobalScope
-import kotlinx.coroutines.async
-import kotlinx.coroutines.delay
 import kotlinx.coroutines.launch
-import kotlinx.coroutines.runBlocking
-import kotlin.system.exitProcess
-import kotlin.time.Duration
 
-// Counters for monitoring the pushprox itself, compatible with the reference implementation in go.
+// Counters for monitoring the pushprox itself, compatible with the reference
+// implementation in golang, source: https://github.dev/prometheus-community/PushProx
 private class Counters(collectorRegistry: CollectorRegistry?) {
     private val collectorRegistry : CollectorRegistry?
     private lateinit var scrapeErrorCounter : Counter
     private lateinit var pushErrorCounter : Counter
     private lateinit var pollErrorCounter : Counter
-    private lateinit var pollSuccessCounter : Counter
     private var enabled : Boolean = false
 
     init {
@@ -57,12 +43,6 @@ private class Counters(collectorRegistry: CollectorRegistry?) {
                 .name("pushprox_client_poll_errors_total")
                 .help("Number of poll errors")
                 .register(collectorRegistry)
-
-            // custom
-            pollSuccessCounter = Counter.build()
-                .name("pushprox_client_poll_total")
-                .help("Number of succesfull polls")
-                .register(collectorRegistry)
         }
     }
 
@@ -71,8 +51,6 @@ private class Counters(collectorRegistry: CollectorRegistry?) {
     fun pushError(){ if (enabled) pushErrorCounter.inc() }
 
     fun pollError(){ if (enabled) pollErrorCounter.inc() }
-
-    fun pollSuccess(){ if (enabled) pollSuccessCounter.inc() }
 }
 
 // Configuration object for this pushprox client
@@ -85,18 +63,22 @@ data class PushProxConfig(
     val performScrape: suspend () -> String,
 )
 
-// error in parsing HTTP header "Id" from HTTP request from Prometheus
+// Error in parsing HTTP header "Id" from HTTP request from Prometheus
 class PushProxIdParseException(message: String) : Exception(message)
 
 // This is a stripped down kotlin implementation of github.com/prometheus-community/PushProx client
 class PushProxClient(config: PushProxConfig) {
-    //TODO dispose this thing - delete http client
+
+    //TODO dispose this thing - delete http client - something like the bellow stuff
+    //val status = HttpClient().use { client ->
+    //    // ...
+    //}
+
     private val config: PushProxConfig
     private val pollURL: String
     private val pushURL: String
     private lateinit var client: HttpClient
     private lateinit var counters : Counters
-    private var running : Boolean = false
 
     init {
         this.config = config
@@ -109,19 +91,20 @@ class PushProxClient(config: PushProxConfig) {
         pushURL = "$modifiedProxyURL/push"
     }
 
-    // initialize resource - heavier objects
+    // Initialize resources - heavier objects
     private fun setup(){
         // init counters if they are enabled
         counters = Counters(config.collectorRegistry)
         client = HttpClient(CIO)
     }
 
-    // use this function to start exporting metrics to pushprox in the background
+    // Use this function to start exporting metrics to pushprox in the background
     public fun startBackground() {
         setup()
         loop(newBackoffFromFlags())
     }
 
+    // Continuous poll from android phone to pushprox gateway
     private suspend fun doPoll(){
         log("poll", "polling now")
         log(pollURL, pollURL)
@@ -131,12 +114,6 @@ class PushProxClient(config: PushProxConfig) {
         log("here", "here")
         val responseBody: String = response.body<String>()
         doPush(responseBody)
-        // response body is not needed
-        log("responseBody in poll", responseBody)
-        log("got scrape request", responseBody)
-
-        //TODO asap
-
     }
 
     // get value of HTTP header "Id" from response body
@@ -150,10 +127,19 @@ class PushProxClient(config: PushProxConfig) {
         return id
     }
 
-    // responseBody: response body of /poll request
-    private suspend fun doPush(responseBody : String) {
-        //TODO implement
+    private fun composeRequestBody(scrapedMetrics: String, id : String) : String {
+        val httpHeaders = "HTTP/1.1 200 OK\r\n" +
+            "Content-Type: text/plain; version=0.0.4; charset=utf-8\r\n" +
+            "Id: $id\r\n" +
+            "X-Prometheus-Scrape-Timeout: 9.5\r\n"
 
+        val result : String = httpHeaders + "\r\n" + scrapedMetrics
+        log("result", result)
+        return result
+    }
+
+    // Parameter responseBody: response body of /poll request
+    private suspend fun doPush(pollResponseBody : String) {
         // perform scrape
         lateinit var scrapedMetrics : String
         try {
@@ -165,15 +151,12 @@ class PushProxClient(config: PushProxConfig) {
         }
 
         try{
-            log("scraped metrics in doPush", scrapedMetrics)
-            val scrapeId : String = getIdFromResponseBody(responseBody)
-            log("scrapeId", scrapeId)
-            val response : HttpResponse = client.request(pushURL) {
-                header("id", scrapeId)
-                //header("X-prometheus-scrape-timeout", "4") //TODO this is dummy for now
-                method = HttpMethod.Post
+            val scrapeId : String = getIdFromResponseBody(pollResponseBody)
+            val pushResponseBody: String = composeRequestBody(scrapedMetrics, scrapeId)
 
-                setBody(scrapedMetrics)
+            val response : HttpResponse = client.request(pushURL) {
+                method = HttpMethod.Post
+                setBody(pushResponseBody)
             }
 
         }catch(e : Exception){
@@ -184,10 +167,6 @@ class PushProxClient(config: PushProxConfig) {
 
     }
 
-    private fun handleErr(){
-        //TODO implement
-    }
-
     private fun newBackoffFromFlags() : StrategyBackoff<Unit> {
         return StrategyBackoff<Unit>(
             strategy = ExponentialStrategy(
@@ -198,8 +177,7 @@ class PushProxClient(config: PushProxConfig) {
         )
     }
 
-
-
+    //TODO migrate to work manager
     private fun loop(backoff: StrategyBackoff<Unit>) {
         // fire and forget a new coroutine
         GlobalScope.launch {
@@ -217,9 +195,8 @@ class PushProxClient(config: PushProxConfig) {
                                 throw e
                             }
                         }
-                        log("pushprox main loop", "loop end")
                     }
-                    job.join()
+                    job.join() // wait for the job to finish
                 }
             }
         }

server/configuration/prometheus.yaml

@@ -10,8 +10,9 @@ scrape_configs:
   
   - job_name: "android phones"
     proxy_url: "http://pushprox:8080" #TODO add mobile phones here
+    tls_config:
+      insecure_skip_verify: true
     static_configs:
       - targets: [
           "test.example.com"
         ]
-