Dispose of http client in tests

OhmGraphite.Test/GraphiteTest.cs

@@ -16,10 +16,12 @@ namespace OhmGraphite.Test
             // wait for carbon to sync to disk
             Thread.Sleep(TimeSpan.FromSeconds(4));
 
-            var client = new HttpClient();
-            var resp = await client.GetAsync("http://graphite/render?format=csv&target=ohm.my-pc.intelcpu.0.temperature.cpucore.1");
-            var content = await resp.Content.ReadAsStringAsync();
-            Assert.Contains("ohm.my-pc.intelcpu.0.temperature.cpucore.1", content);
+            using (var client = new HttpClient())
+            {
+                var resp = await client.GetAsync("http://graphite/render?format=csv&target=ohm.my-pc.intelcpu.0.temperature.cpucore.1");
+                var content = await resp.Content.ReadAsStringAsync();
+                Assert.Contains("ohm.my-pc.intelcpu.0.temperature.cpucore.1", content);
+            }
         }
 
         [Fact, Trait("Category", "integration")]
@@ -34,12 +36,14 @@ namespace OhmGraphite.Test
             // wait for carbon to sync to disk
             Thread.Sleep(TimeSpan.FromSeconds(4));
 
-            var client = new HttpClient();
-            var resp = await client.GetAsync("http://graphite/render?format=csv&target=seriesByTag('sensor_type=Temperature','hardware_type=CPU')");
-            var content = await resp.Content.ReadAsStringAsync();
-            Assert.Contains("host=my-pc", content);
-            Assert.Contains("app=ohm", content);
-            Assert.Contains("sensor_type=Temperature", content);
+            using (var client = new HttpClient())
+            {
+                var resp = await client.GetAsync("http://graphite/render?format=csv&target=seriesByTag('sensor_type=Temperature','hardware_type=CPU')");
+                var content = await resp.Content.ReadAsStringAsync();
+                Assert.Contains("host=my-pc", content);
+                Assert.Contains("app=ohm", content);
+                Assert.Contains("sensor_type=Temperature", content);
+            }
         }
     }
 }

OhmGraphite.Test/InfluxTest.cs

@@ -15,11 +15,13 @@ namespace OhmGraphite.Test
             await writer.ReportMetrics(DateTime.Now, TestSensorCreator.Values());
 
             Thread.Sleep(TimeSpan.FromSeconds(1));
-            var client = new HttpClient();
-            var resp = await client.GetAsync("http://influx:8086/query?pretty=true&db=mydb&q=SELECT%20*%20FROM%20Temperature");
-            Assert.True(resp.IsSuccessStatusCode);
-            var content = await resp.Content.ReadAsStringAsync();
-            Assert.Contains("/intelcpu/0/temperature/0", content);
+            using (var client = new HttpClient())
+            {
+                var resp = await client.GetAsync("http://influx:8086/query?pretty=true&db=mydb&q=SELECT%20*%20FROM%20Temperature");
+                Assert.True(resp.IsSuccessStatusCode);
+                var content = await resp.Content.ReadAsStringAsync();
+                Assert.Contains("/intelcpu/0/temperature/0", content);
+            }
         }
     }
 }

OhmGraphite.Test/PrometheusTest.cs

@@ -15,9 +15,9 @@ namespace OhmGraphite.Test
             var registry = PrometheusCollection.SetupDefault(collector);
             var mserver = new MetricServer("localhost", 21881, registry: registry);
             using (var server = new PrometheusServer(mserver, collector))
+            using (var client = new HttpClient())
             {
                 server.Start();
-                var client = new HttpClient();
                 var resp = await client.GetAsync("http://localhost:21881/metrics");
                 Assert.True(resp.IsSuccessStatusCode);
                 var content = await resp.Content.ReadAsStringAsync();
@@ -32,9 +32,9 @@ namespace OhmGraphite.Test
             var registry = PrometheusCollection.SetupDefault(collector);
             var mserver = new MetricServer("localhost", 21882, registry: registry);
             using (var server = new PrometheusServer(mserver, collector))
+            using (var client = new HttpClient())
             {
                 server.Start();
-                var client = new HttpClient();
                 var resp = await client.GetAsync("http://localhost:21882/metrics");
                 Assert.True(resp.IsSuccessStatusCode);
                 var content = await resp.Content.ReadAsStringAsync();