Adds support for some attributes in experimental Go SDK (#29)

#25

---------

Signed-off-by: Takeshi Yoneda <t.y.mathetake@gmail.com>

Author: mathetake

go/gosdk/abi.go

@@ -119,6 +119,13 @@ size_t envoy_dynamic_module_callback_http_get_response_headers_count(
 bool envoy_dynamic_module_callback_http_get_response_headers(
     uintptr_t filter_envoy_ptr,
     uintptr_t* result_headers);
+
+#cgo noescape envoy_dynamic_module_callback_http_filter_get_attribute_string
+#cgo nocallback envoy_dynamic_module_callback_http_filter_get_attribute_string
+bool envoy_dynamic_module_callback_http_filter_get_attribute_string(
+    uintptr_t filter_envoy_ptr,
+    size_t attribute_id,
+    uintptr_t* result, size_t* result_length);
 */
 import "C"
 
@@ -375,6 +382,33 @@ type envoySlice struct {
 // envoyFilter implements [EnvoyHttpFilter].
 type envoyFilter struct{ raw uintptr }
 
+// GetRequestProtocol implements [EnvoyHttpFilter].
+func (e envoyFilter) GetRequestProtocol() string {
+	// https://github.com/envoyproxy/envoy/blob/05223ee2cd143d70b32402783c2a866a9dd18bd1/source/extensions/dynamic_modules/abi.h#L237-L372
+	return e.getStringAttribute(10) // request.protocol
+}
+
+// GetSourceAddress implements [EnvoyHttpFilter].
+func (e envoyFilter) GetSourceAddress() string {
+	// https://github.com/envoyproxy/envoy/blob/05223ee2cd143d70b32402783c2a866a9dd18bd1/source/extensions/dynamic_modules/abi.h#L237-L372
+	return e.getStringAttribute(24) // source.address
+}
+
+func (e envoyFilter) getStringAttribute(id int) string {
+	var resultBufferPtr *byte
+	var resultBufferLengthPtr int
+	ret := C.envoy_dynamic_module_callback_http_filter_get_attribute_string(
+		C.uintptr_t(e.raw),
+		C.size_t(id),
+		(*C.uintptr_t)(unsafe.Pointer(&resultBufferPtr)),
+		(*C.size_t)(unsafe.Pointer(&resultBufferLengthPtr)),
+	)
+	if !ret {
+		return ""
+	}
+	return string(unsafe.Slice(resultBufferPtr, resultBufferLengthPtr)) // Copy the result to a Go string.
+}
+
 // GetRequestHeaders implements EnvoyHttpFilter.
 func (e envoyFilter) GetRequestHeaders() map[string][]string {
 	count := C.envoy_dynamic_module_callback_http_get_request_headers_count(C.uintptr_t(e.raw))

go/gosdk/gosdk.go

@@ -54,6 +54,11 @@ type EnvoyHttpFilter interface {
 	AppendResponseBody(data []byte) bool
 	// SendLocalReply sends a local reply to the client. This must not be used in after returning continue from the response headers phase.
 	SendLocalReply(statusCode uint32, headers [][2]string, body []byte)
+	// GetSourceAddress gets the source address of the request in the format of "IP:PORT".
+	// This corresponds to `source.address` attribute https://www.envoyproxy.io/docs/envoy/latest/intro/arch_overview/advanced/attributes.
+	GetSourceAddress() string
+	// GetRequestProtocol gets the request protocol. This corresponds to `request.protocol` attribute https://www.envoyproxy.io/docs/envoy/latest/intro/arch_overview/advanced/attributes.
+	GetRequestProtocol() string
 }
 
 // HttpFilter is an interface that represents each Http request.

go/passthrough.go

@@ -33,6 +33,8 @@ func (p passthroughFilter) RequestHeaders(e gosdk.EnvoyHttpFilter, endOfStream b
 			fmt.Printf("gosdk: RequestHeaders, header: %s: %s\n", k, v)
 		}
 	}
+	fmt.Printf("gosdk: RequestHeaders, source address: %s\n", e.GetSourceAddress())
+	fmt.Printf("gosdk: RequestHeaders, request protocol: %s\n", e.GetRequestProtocol())
 	return gosdk.RequestHeadersStatusContinue
 }
 

integration/main_test.go

@@ -55,10 +55,6 @@ func TestIntegration(t *testing.T) {
 	require.NoError(t, cmd.Start())
 	t.Cleanup(func() { require.NoError(t, cmd.Process.Signal(os.Interrupt)) })
 
-	// Let's wait at least 5 seconds for Envoy to start since it might take a while
-	// to pull the image.
-	time.Sleep(5 * time.Second)
-
 	t.Run("http_access_logger", func(t *testing.T) {
 		t.Run("health checking", func(t *testing.T) {
 			require.Eventually(t, func() bool {
@@ -80,7 +76,7 @@ func TestIntegration(t *testing.T) {
 				}
 				t.Logf("response: status=%d body=%s", resp.StatusCode, string(body))
 				return resp.StatusCode == 200
-			}, 30*time.Second, 1*time.Second)
+			}, 120*time.Second, 1*time.Second)
 		})
 
 		require.Eventually(t, func() bool {