Plugins: Automatically forward plugin request HTTP headers in outgoing HTTP requests (#60417)

Automatically forward core plugin request HTTP headers in outgoing HTTP requests. 
Core datasource plugin authors don't have to specifically handle forwarding of HTTP 
headers, e.g. do not have to "hardcode" the header-names in the datasource plugin, 
if not having custom needs.

Fixes #57065

pkg/infra/httpclient/httpclientprovider/delete_headers_middleware.go

@@ -1,27 +0,0 @@
-package httpclientprovider
-
-import (
-	"net/http"
-
-	"github.com/grafana/grafana-plugin-sdk-go/backend/httpclient"
-)
-
-const DeleteHeadersMiddlewareName = "delete-headers"
-
-// DeleteHeadersMiddleware middleware that delete headers on the outgoing
-// request if header names provided.
-func DeleteHeadersMiddleware(headerNames ...string) httpclient.Middleware {
-	return httpclient.NamedMiddlewareFunc(DeleteHeadersMiddlewareName, func(opts httpclient.Options, next http.RoundTripper) http.RoundTripper {
-		if len(headerNames) == 0 {
-			return next
-		}
-
-		return httpclient.RoundTripperFunc(func(req *http.Request) (*http.Response, error) {
-			for _, k := range headerNames {
-				req.Header.Del(k)
-			}
-
-			return next.RoundTrip(req)
-		})
-	})
-}

pkg/infra/httpclient/httpclientprovider/delete_headers_middleware_test.go

@@ -1,66 +0,0 @@
-package httpclientprovider
-
-import (
-	"net/http"
-	"testing"
-
-	"github.com/grafana/grafana-plugin-sdk-go/backend/httpclient"
-	"github.com/stretchr/testify/require"
-)
-
-func TestDeleteHeadersMiddleware(t *testing.T) {
-	t.Run("Without headerNames should return next http.RoundTripper", func(t *testing.T) {
-		ctx := &testContext{}
-		finalRoundTripper := ctx.createRoundTripper("finalrt")
-		var headerNames []string
-		mw := DeleteHeadersMiddleware(headerNames...)
-		rt := mw.CreateMiddleware(httpclient.Options{}, finalRoundTripper)
-		require.NotNil(t, rt)
-		middlewareName, ok := mw.(httpclient.MiddlewareName)
-		require.True(t, ok)
-		require.Equal(t, DeleteHeadersMiddlewareName, 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)
-	})
-
-	t.Run("With headers set should apply HTTP headers to the request", func(t *testing.T) {
-		ctx := &testContext{}
-		finalRoundTripper := ctx.createRoundTripper("final")
-		headerNames := []string{"X-Header-B", "X-Header-C"}
-		mw := DeleteHeadersMiddleware(headerNames...)
-		rt := mw.CreateMiddleware(httpclient.Options{}, finalRoundTripper)
-		require.NotNil(t, rt)
-		middlewareName, ok := mw.(httpclient.MiddlewareName)
-		require.True(t, ok)
-		require.Equal(t, DeleteHeadersMiddlewareName, middlewareName.MiddlewareName())
-
-		req, err := http.NewRequest(http.MethodGet, "http://", nil)
-		require.NoError(t, err)
-		req.Header.Set("X-Header-A", "a")
-		req.Header.Set("X-Header-B", "b")
-		req.Header.Set("X-Header-C", "c")
-		req.Header.Set("X-Header-D", "d")
-		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{"final"}, ctx.callChain)
-
-		require.Equal(t, "a", req.Header.Get("X-Header-A"))
-		require.Empty(t, req.Header.Get("X-Header-B"))
-		require.Empty(t, req.Header.Get("X-Header-C"))
-		require.Equal(t, "d", req.Header.Get("X-Header-D"))
-	})
-}

pkg/infra/httpclient/httpclientprovider/set_headers_middleware.go

@@ -1,31 +0,0 @@
-package httpclientprovider
-
-import (
-	"net/http"
-	"net/textproto"
-
-	"github.com/grafana/grafana-plugin-sdk-go/backend/httpclient"
-)
-
-const SetHeadersMiddlewareName = "set-headers"
-
-// SetHeadersMiddleware middleware that sets headers on the outgoing
-// request if headers provided.
-// If the request already contains any of the headers provided, they
-// will be overwritten.
-func SetHeadersMiddleware(headers http.Header) httpclient.Middleware {
-	return httpclient.NamedMiddlewareFunc(SetHeadersMiddlewareName, func(opts httpclient.Options, next http.RoundTripper) http.RoundTripper {
-		if len(headers) == 0 {
-			return next
-		}
-
-		return httpclient.RoundTripperFunc(func(req *http.Request) (*http.Response, error) {
-			for k, v := range headers {
-				canonicalKey := textproto.CanonicalMIMEHeaderKey(k)
-				req.Header[canonicalKey] = v
-			}
-
-			return next.RoundTrip(req)
-		})
-	})
-}

pkg/infra/httpclient/httpclientprovider/set_headers_middleware_test.go

@@ -1,66 +0,0 @@
-package httpclientprovider
-
-import (
-	"net/http"
-	"testing"
-
-	"github.com/grafana/grafana-plugin-sdk-go/backend/httpclient"
-	"github.com/stretchr/testify/require"
-)
-
-func TestSetHeadersMiddleware(t *testing.T) {
-	t.Run("Without headers set should return next http.RoundTripper", func(t *testing.T) {
-		ctx := &testContext{}
-		finalRoundTripper := ctx.createRoundTripper("finalrt")
-		var headers http.Header
-		mw := SetHeadersMiddleware(headers)
-		rt := mw.CreateMiddleware(httpclient.Options{}, finalRoundTripper)
-		require.NotNil(t, rt)
-		middlewareName, ok := mw.(httpclient.MiddlewareName)
-		require.True(t, ok)
-		require.Equal(t, SetHeadersMiddlewareName, 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)
-	})
-
-	t.Run("With headers set should apply HTTP headers to the request", func(t *testing.T) {
-		ctx := &testContext{}
-		finalRoundTripper := ctx.createRoundTripper("final")
-		headers := http.Header{
-			"X-Header-A": []string{"value a"},
-			"X-Header-B": []string{"value b"},
-			"X-HEader-C": []string{"value c"},
-		}
-		mw := SetHeadersMiddleware(headers)
-		rt := mw.CreateMiddleware(httpclient.Options{}, finalRoundTripper)
-		require.NotNil(t, rt)
-		middlewareName, ok := mw.(httpclient.MiddlewareName)
-		require.True(t, ok)
-		require.Equal(t, SetHeadersMiddlewareName, middlewareName.MiddlewareName())
-
-		req, err := http.NewRequest(http.MethodGet, "http://", nil)
-		require.NoError(t, err)
-		req.Header.Set("X-Header-B", "d")
-		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{"final"}, ctx.callChain)
-
-		require.Equal(t, "value a", req.Header.Get("X-Header-A"))
-		require.Equal(t, "value b", req.Header.Get("X-Header-B"))
-		require.Equal(t, "value c", req.Header.Get("X-Header-C"))
-	})
-}