Datasource: Shared HTTP client provider for core backend data sources and any data source using the data source proxy (#33439)

Uses new httpclient package from grafana-plugin-sdk-go introduced via grafana/grafana-plugin-sdk-go#328. Replaces the GetHTTPClient, GetTransport, GetTLSConfig methods defined on DataSource model. Longer-term the goal is to migrate core HTTP backend data sources to use the SDK contracts and using httpclient.Provider for creating HTTP clients and such. Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com>
2021-05-19 23:53:41 +02:00
parent 7a83d1f9ff
commit 348e76fc8e
46 changed files with 1082 additions and 467 deletions
@@ -0,0 +1,130 @@
+package httpclientprovider
+
+import (
+	"net/http"
+	"testing"
+
+	"github.com/grafana/grafana-plugin-sdk-go/backend/httpclient"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/stretchr/testify/require"
+)
+
+func TestDataSourceMetricsMiddleware(t *testing.T) {
+	t.Run("Without label options set should return next http.RoundTripper", func(t *testing.T) {
+		origExecuteMiddlewareFunc := executeMiddlewareFunc
+		executeMiddlewareCalled := false
+		middlewareCalled := false
+		executeMiddlewareFunc = func(next http.RoundTripper, datasourceLabel prometheus.Labels) http.RoundTripper {
+			executeMiddlewareCalled = true
+			return httpclient.RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
+				middlewareCalled = true
+				return next.RoundTrip(r)
+			})
+		}
+		t.Cleanup(func() {
+			executeMiddlewareFunc = origExecuteMiddlewareFunc
+		})
+
+		ctx := &testContext{}
+		finalRoundTripper := ctx.createRoundTripper("finalrt")
+		mw := DataSourceMetricsMiddleware()
+		rt := mw.CreateMiddleware(httpclient.Options{}, finalRoundTripper)
+		require.NotNil(t, rt)
+		middlewareName, ok := mw.(httpclient.MiddlewareName)
+		require.True(t, ok)
+		require.Equal(t, DataSourceMetricsMiddlewareName, middlewareName.MiddlewareName())
+
+		req, err := http.NewRequest(http.MethodGet, "http://", nil)
+		require.NoError(t, err)
+		res, err := rt.RoundTrip(req)
+		require.NoError(t, err)
+		require.NotNil(t, res)
+		if res.Body != nil {
+			require.NoError(t, res.Body.Close())
+		}
+		require.Len(t, ctx.callChain, 1)
+		require.ElementsMatch(t, []string{"finalrt"}, ctx.callChain)
+		require.False(t, executeMiddlewareCalled)
+		require.False(t, middlewareCalled)
+	})
+
+	t.Run("Without data source name label options set should return next http.RoundTripper", func(t *testing.T) {
+		origExecuteMiddlewareFunc := executeMiddlewareFunc
+		executeMiddlewareCalled := false
+		middlewareCalled := false
+		executeMiddlewareFunc = func(next http.RoundTripper, datasourceLabel prometheus.Labels) http.RoundTripper {
+			executeMiddlewareCalled = true
+			return httpclient.RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
+				middlewareCalled = true
+				return next.RoundTrip(r)
+			})
+		}
+		t.Cleanup(func() {
+			executeMiddlewareFunc = origExecuteMiddlewareFunc
+		})
+
+		ctx := &testContext{}
+		finalRoundTripper := ctx.createRoundTripper("finalrt")
+		mw := DataSourceMetricsMiddleware()
+		rt := mw.CreateMiddleware(httpclient.Options{Labels: map[string]string{"test": "test"}}, finalRoundTripper)
+		require.NotNil(t, rt)
+		middlewareName, ok := mw.(httpclient.MiddlewareName)
+		require.True(t, ok)
+		require.Equal(t, DataSourceMetricsMiddlewareName, middlewareName.MiddlewareName())
+
+		req, err := http.NewRequest(http.MethodGet, "http://", nil)
+		require.NoError(t, err)
+		res, err := rt.RoundTrip(req)
+		require.NoError(t, err)
+		require.NotNil(t, res)
+		if res.Body != nil {
+			require.NoError(t, res.Body.Close())
+		}
+		require.Len(t, ctx.callChain, 1)
+		require.ElementsMatch(t, []string{"finalrt"}, ctx.callChain)
+		require.False(t, executeMiddlewareCalled)
+		require.False(t, middlewareCalled)
+	})
+
+	t.Run("With datasource name label options set should execute middleware", func(t *testing.T) {
+		origExecuteMiddlewareFunc := executeMiddlewareFunc
+		executeMiddlewareCalled := false
+		datasourceLabels := prometheus.Labels{}
+		middlewareCalled := false
+		executeMiddlewareFunc = func(next http.RoundTripper, datasourceLabel prometheus.Labels) http.RoundTripper {
+			executeMiddlewareCalled = true
+			datasourceLabels = datasourceLabel
+			return httpclient.RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
+				middlewareCalled = true
+				return next.RoundTrip(r)
+			})
+		}
+		t.Cleanup(func() {
+			executeMiddlewareFunc = origExecuteMiddlewareFunc
+		})
+
+		ctx := &testContext{}
+		finalRoundTripper := ctx.createRoundTripper("finalrt")
+		mw := DataSourceMetricsMiddleware()
+		rt := mw.CreateMiddleware(httpclient.Options{Labels: map[string]string{"datasource_name": "My Data Source 123"}}, finalRoundTripper)
+		require.NotNil(t, rt)
+		middlewareName, ok := mw.(httpclient.MiddlewareName)
+		require.True(t, ok)
+		require.Equal(t, DataSourceMetricsMiddlewareName, middlewareName.MiddlewareName())
+
+		req, err := http.NewRequest(http.MethodGet, "http://", nil)
+		require.NoError(t, err)
+		res, err := rt.RoundTrip(req)
+		require.NoError(t, err)
+		require.NotNil(t, res)
+		if res.Body != nil {
+			require.NoError(t, res.Body.Close())
+		}
+		require.Len(t, ctx.callChain, 1)
+		require.ElementsMatch(t, []string{"finalrt"}, ctx.callChain)
+		require.True(t, executeMiddlewareCalled)
+		require.Len(t, datasourceLabels, 1)
+		require.Equal(t, "My_Data_Source_123", datasourceLabels["datasource"])
+		require.True(t, middlewareCalled)
+	})
+}