fix discovery, add metrics to receiver

3d_party/mongoose/install.sh

+wget https://raw.githubusercontent.com/cesanta/mongoose/7.4/mongoose.c
+wget https://raw.githubusercontent.com/cesanta/mongoose/7.4/mongoose.h
\ No newline at end of file

discovery/src/asapo_discovery/server/server.go

 package server
 
 import (
-	"asapo_discovery/request_handler"
 	"asapo_discovery/common"
+	"asapo_discovery/request_handler"
+	"github.com/prometheus/client_golang/prometheus"
 )
 
 var requestHandler request_handler.Agent
@@ -10,6 +11,15 @@ var requestHandler request_handler.Agent
 
 var settings common.Settings
 
+var (
+	nReqests = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Name: "http_requests",
+			Help: "Number of discovery requests",
+		},
+	)
+)
+
 func SetHandler(rh request_handler.Agent) error {
 	requestHandler = rh
 	err := requestHandler.Init(settings)

discovery/src/asapo_discovery/server/server_nottested.go

@@ -13,15 +13,6 @@ import (
 	"strconv"
 )
 
-var (
-	nReqests = prometheus.NewCounter(
-		prometheus.CounterOpts{
-			Name: "http_requests",
-			Help: "Number of discovery requests",
-		},
-	)
-)
-
 func init() {
 	prometheus.MustRegister(nReqests)
 }

receiver/CMakeLists.txt

@@ -28,6 +28,8 @@ set(RECEIVER_CORE_FILES
         src/file_processors/write_file_processor.cpp
         src/file_processors/file_processor.cpp
         src/file_processors/receive_file_processor.cpp
+        src/metrics/receiver_prometheus_metrics.cpp
+        src/metrics/receiver_mongoose_server.cpp
         )
 
 set(RDS_FILES

receiver/src/main.cpp

@@ -12,6 +12,9 @@
 #include "receiver_data_server/net_server/rds_tcp_server.h"
 #include "receiver_data_server/net_server/rds_fabric_server.h"
 
+#include "metrics/receiver_prometheus_metrics.h"
+#include "metrics/receiver_mongoose_server.h"
+
 asapo::Error ReadConfigFile(int argc, char* argv[]) {
     if (argc != 2) {
         std::cerr << "Usage: " << argv[0] << " <config file>" << std::endl;
@@ -88,10 +91,18 @@ int StartReceiver(const asapo::ReceiverConfig* config, asapo::SharedCache cache,
     return 0;
 }
 
+asapo::Error StartMetricsServer() {
+    auto srv = std::unique_ptr<asapo::ReceiverMetricsServer>(new asapo::ReceiverMongooseServer());
+    auto* provider = new asapo::ReceiverPrometheusMetrics();
+    srv->ListenAndServe("7009", std::unique_ptr<asapo::ReceiverMetricsProvider>(provider));
+    return nullptr;
+}
 
 int main (int argc, char* argv[]) {
     asapo::ExitAfterPrintVersionIfNeeded("ASAPO Receiver", argc, argv);
 
+//    StartMetricsServer();
+
     auto err = ReadConfigFile(argc, argv);
     const auto& logger = asapo::GetDefaultReceiverLogger();
     if (err) {

receiver/src/metrics/receiver_metrics_provider.h

+#ifndef ASAPO_RECEIVER_SRC_METRICS_RECEIVER_METRICS_PROVIDER_H_
+#define ASAPO_RECEIVER_SRC_METRICS_RECEIVER_METRICS_PROVIDER_H_
+
+#include <string>
+
+namespace asapo {
+
+class ReceiverMetricsProvider {
+  public:
+    virtual std::string Metrics() const = 0;
+    virtual ~ReceiverMetricsProvider() = default;
+};
+
+
+}
+
+
+
+#endif //ASAPO_RECEIVER_SRC_METRICS_RECEIVER_METRICS_PROVIDER_H_

receiver/src/metrics/receiver_metrics_server.h

+#ifndef ASAPO_RECEIVER_SRC_METRICS_RECEIVER_METRICS_SERVER_H_
+#define ASAPO_RECEIVER_SRC_METRICS_RECEIVER_METRICS_SERVER_H_
+
+#include "asapo/common/error.h"
+#include "receiver_metrics_provider.h"
+
+namespace asapo {
+
+class ReceiverMetricsServer {
+  public:
+    virtual Error ListenAndServe(std::string port, std::unique_ptr<ReceiverMetricsProvider> provider) = 0;
+    virtual ~ReceiverMetricsServer() = default;
+};
+
+}
+
+#endif //ASAPO_RECEIVER_SRC_METRICS_RECEIVER_METRICS_SERVER_H_

receiver/src/metrics/receiver_mongoose_server.cpp

+#include "receiver_mongoose_server.h"
+
+#include "../../../3d_party/mongoose/mongoose.h"
+#include "../../../3d_party/mongoose/mongoose.c"
+
+namespace asapo {
+
+static void fn(struct mg_connection* c, int ev, void* ev_data, void* fn_data) {
+    auto provider = static_cast<const ReceiverMetricsProvider*>(fn_data);
+    if (ev == MG_EV_HTTP_MSG) {
+        struct mg_http_message* hm = (struct mg_http_message*) ev_data;
+        if (mg_http_match_uri(hm, "/metrics")) {
+            mg_http_reply(c, 200, "", "{\"result\": %s}\n", provider->Metrics().c_str());
+        } else {
+            mg_http_reply(c, 404, "", "%s", "Not found\n");
+        }
+    }
+}
+
+asapo::Error asapo::ReceiverMongooseServer::ListenAndServe(std::string port,
+        std::unique_ptr<ReceiverMetricsProvider> provider) {
+    struct mg_mgr mgr;                            // Event manager
+    mg_mgr_init(&mgr);                            // Initialise event manager
+    auto uri = "0.0.0.0:" + port;
+    if (mg_http_listen(&mgr, uri.c_str(), fn, (void*) provider.get()) == NULL) {
+        LOG(LL_ERROR, ("Cannot listen on %s. Use http://ADDR:PORT or :PORT",
+                       port.c_str()));
+        exit(EXIT_FAILURE);
+    }
+    for (;;) mg_mgr_poll(&mgr, 1000);                    // Infinite event loop
+    mg_mgr_free(&mgr);
+    return nullptr;
+}
+
+}
+
+

receiver/src/metrics/receiver_mongoose_server.h

+#ifndef ASAPO_RECEIVER_SRC_METRICS_RECEIVER_MONGOOSE_SERVER_H_
+#define ASAPO_RECEIVER_SRC_METRICS_RECEIVER_MONGOOSE_SERVER_H_
+
+#include "receiver_metrics_server.h"
+
+namespace asapo {
+class ReceiverMongooseServer final :  public ReceiverMetricsServer {
+  public:
+    Error ListenAndServe(std::string port, std::unique_ptr<ReceiverMetricsProvider> provider) override;
+
+};
+
+}
+
+
+
+#endif //ASAPO_RECEIVER_SRC_METRICS_RECEIVER_MONGOOSE_SERVER_H_

receiver/src/metrics/receiver_prometheus_metrics.cpp

+#include "receiver_prometheus_metrics.h"
+
+namespace  asapo {
+
+std::string ReceiverPrometheusMetrics::Metrics() const {
+    return "hello";
+}
+
+}
+
+

receiver/src/metrics/receiver_prometheus_metrics.h

+#ifndef ASAPO_RECEIVER_SRC_METRICS_RECEIVER_PROMETHEUS_METRICS_H_
+#define ASAPO_RECEIVER_SRC_METRICS_RECEIVER_PROMETHEUS_METRICS_H_
+
+#include "receiver_metrics_provider.h"
+
+namespace asapo {
+
+class ReceiverPrometheusMetrics final : public ReceiverMetricsProvider {
+  public:
+    std::string Metrics() const override;
+
+};
+
+}
+
+#endif //ASAPO_RECEIVER_SRC_METRICS_RECEIVER_PROMETHEUS_METRICS_H_