Implement ping

Author: offa

include/InfluxDB/InfluxDB.h

@@ -92,6 +92,9 @@ namespace influxdb
         /// \param precision
         void setTimePrecision(TimePrecision precision);
 
+        /// Check instance is up and running
+        bool ping();
+
     private:
         void addPointToBatch(Point&& point);
         std::string joinLineProtocolBatch() const;

include/InfluxDB/Transport.h

@@ -75,6 +75,11 @@ namespace influxdb
         {
             throw InfluxDBException{"Time precision is not supported by the selected transport"};
         }
+
+        virtual bool ping()
+        {
+            throw InfluxDBException{"Ping is not supported by the selected transport"};
+        }
     };
 
 } // namespace influxdb

src/HTTP.cxx

@@ -173,6 +173,14 @@ namespace influxdb::transports
         }
     }
 
+    bool HTTP::ping()
+    {
+        session.SetUrl(cpr::Url{endpointUrl + "/ping"});
+
+        const auto response = session.Get();
+        return response.status_code == cpr::status::HTTP_NO_CONTENT;
+    }
+
     std::string HTTP::execute(const std::string& cmd)
     {
         session.SetUrl(cpr::Url{endpointUrl + "/query"});

src/HTTP.h

@@ -75,6 +75,7 @@ namespace influxdb::transports
         void setVerifyCertificate(bool verify);
         void setTimeout(std::chrono::milliseconds timeout);
         void setTimePrecision(TimePrecision precision) override;
+        bool ping() override;
 
     private:
         std::string endpointUrl;

src/InfluxDB.cxx

@@ -151,6 +151,11 @@ namespace influxdb
         mTransport->setTimePrecision(precision);
     }
 
+    bool InfluxDB::ping()
+    {
+        return mTransport->ping();
+    }
+
     void InfluxDB::addPointToBatch(Point&& point)
     {
         mPointBatch.emplace_back(std::move(point));

test/HttpTest.cxx

@@ -399,4 +399,21 @@ namespace influxdb::test
         REQUIRE_THROWS_AS(http.execute("fail-execution"), InfluxDBException);
     }
 
+    TEST_CASE("Ping returns true if successful", "[HttpTest]")
+    {
+        REQUIRE_CALL(sessionMock, Get()).RETURN(createResponse(cpr::ErrorCode::OK, cpr::status::HTTP_NO_CONTENT, "response-content"));
+        ALLOW_CALL(sessionMock, SetUrl(_));
+
+        auto http = createHttp();
+        CHECK(http.ping());
+    }
+
+    TEST_CASE("Ping returns false if unsuccessful", "[HttpTest]")
+    {
+        REQUIRE_CALL(sessionMock, Get()).RETURN(createResponse(cpr::ErrorCode::COULDNT_CONNECT, cpr::status::HTTP_NOT_FOUND, "response-content"));
+        ALLOW_CALL(sessionMock, SetUrl(_));
+
+        auto http = createHttp();
+        CHECK_FALSE(http.ping());
+    }
 }

test/InfluxDBTest.cxx

@@ -208,4 +208,13 @@ namespace influxdb::test
         db.write(Point{"p"}.addField("f", 1).setTimestamp(std::chrono::time_point<std::chrono::system_clock>{std::chrono::milliseconds{67}}));
     }
 
+    TEST_CASE("Ping instance", "[InfluxDBTest]")
+    {
+        auto mock = std::make_shared<TransportMock>();
+        REQUIRE_CALL(*mock, ping()).RETURN(true);
+
+        InfluxDB db{std::make_unique<TransportAdapter>(mock)};
+        CHECK(db.ping());
+    }
+
 }

test/mock/TransportMock.h

@@ -35,6 +35,7 @@ namespace influxdb::test
         MAKE_MOCK0(createDatabase, void(), override);
         MAKE_MOCK1(execute, std::string(const std::string&), override);
         MAKE_MOCK1(setTimePrecision, void(TimePrecision), override);
+        MAKE_MOCK0(ping, bool(), override);
     };
 
 
@@ -71,6 +72,11 @@ namespace influxdb::test
             mockImpl->setTimePrecision(precision);
         }
 
+        bool ping() override
+        {
+            return mockImpl->ping();
+        }
+
     private:
         std::shared_ptr<TransportMock> mockImpl;
     };

test/system/InfluxDBST.cxx

@@ -66,6 +66,18 @@ namespace influxdb::test
 
         auto db = configure("st_db");
 
+        SECTION("Ping up and running instance")
+        {
+            CHECK(db->ping());
+        }
+
+        SECTION("Ping on an up and running instance")
+        {
+            auto nonexistent = InfluxDBBuilder::http("http://not-existing-instance:8086?db=ignore")
+                                   .setTimeout(std::chrono::seconds{2})
+                                   .connect();
+            CHECK_FALSE(nonexistent->ping());
+        }
 
         SECTION("Database does not exist")
         {