Fix gRPC crash, display gRPC as base64, display gRPC URL and status code (#27)

* Added Method (POST) and URL (emtpy) to gRPC requests.

* Removed quickfix that skips writing HTTP/2 to HAR.

* Use HTTP/2 body to fill out http.Request and htt.Response.

* Make sure that in HARs request.postData.mimeType and response.content.mimeType are application/grpc in case of grpc.

* Comment.

* Add URL and status code for gRPC.

* Don't assume http scheme.

* Use http.Header.Set instead of manually acccessing the underlaying map.

api/pkg/tap/grpc_assembler.go

@@ -6,8 +6,11 @@ import (
 	"encoding/base64"
 	"encoding/binary"
 	"errors"
+	"io"
 	"math"
 	"net/http"
+	"net/url"
+	"strings"
 
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
@@ -62,6 +65,7 @@ func (fbs *fragmentsByStream) pop(streamID uint32) ([]hpack.HeaderField, []byte)
 	headers := (*fbs)[streamID].headers
 	data := (*fbs)[streamID].data
 	delete((*fbs), streamID)
+
 	return headers, data
 }
 
@@ -100,9 +104,11 @@ func (ga *GrpcAssembler) readMessage() (uint32, interface{}, string, error) {
 
 	headers, data := ga.fragmentsByStream.pop(streamID)
 
+	// Note: header keys are converted by http.Header.Set to canonical names, e.g. content-type -> Content-Type.
+	// By converting the keys we violate the HTTP/2 specification, which state that all headers must be lowercase.
 	headersHTTP1 := make(http.Header)
 	for _, header := range headers {
-		headersHTTP1[header.Name] = []string{header.Value}
+		headersHTTP1.Add(header.Name, header.Value)
 	}
 	dataString := base64.StdEncoding.EncodeToString(data)
 
@@ -112,10 +118,14 @@ func (ga *GrpcAssembler) readMessage() (uint32, interface{}, string, error) {
 	var messageHTTP1 interface{}
 	if _, ok := headersHTTP1[":method"]; ok {
 		messageHTTP1 = http.Request{
+			URL: &url.URL{},
+			Method: "POST",
 			Header: headersHTTP1,
 			Proto: protoHTTP2,
 			ProtoMajor: protoMajorHTTP2,
 			ProtoMinor: protoMinorHTTP2,
+			Body: io.NopCloser(strings.NewReader(dataString)),
+			ContentLength: int64(len(dataString)),
 		}
 	} else if _, ok := headersHTTP1[":status"]; ok {
 		messageHTTP1 = http.Response{
@@ -123,6 +133,8 @@ func (ga *GrpcAssembler) readMessage() (uint32, interface{}, string, error) {
 			Proto: protoHTTP2,
 			ProtoMajor: protoMajorHTTP2,
 			ProtoMinor: protoMinorHTTP2,
+			Body: io.NopCloser(strings.NewReader(dataString)),
+			ContentLength: int64(len(dataString)),
 		}
 	} else {
 		return 0, nil, "", errors.New("Failed to assemble stream: neither a request nor a message")

api/pkg/tap/har_writer.go

@@ -7,6 +7,8 @@ import (
 	"net/http"
 	"os"
 	"path/filepath"
+	"strconv"
+	"strings"
 	"time"
 
 	"github.com/google/martian/har"
@@ -40,26 +42,41 @@ type HarFile struct {
 }
 
 func NewEntry(request *http.Request, requestTime time.Time, response *http.Response, responseTime time.Time) (*har.Entry, error) {
-	// TODO: quick fix until TRA-3212 is implemented  
-	if request.URL == nil || request.Method == "" {
-		return nil, errors.New("Invalid request")
-	}
 	harRequest, err := har.NewRequest(request, true)
 	if err != nil {
 		SilentError("convert-request-to-har", "Failed converting request to HAR %s (%v,%+v)\n", err, err, err)
 		return nil, errors.New("Failed converting request to HAR")
 	}
 
-	// Martian copies http.Request.URL.String() to har.Request.URL.
-	// According to the spec, the URL field needs to be the absolute URL.
-	harRequest.URL = fmt.Sprintf("http://%s%s", request.Host, request.URL)
-
 	harResponse, err := har.NewResponse(response, true)
 	if err != nil {
 		SilentError("convert-response-to-har", "Failed converting response to HAR %s (%v,%+v)\n", err, err, err)
 		return nil, errors.New("Failed converting response to HAR")
 	}
 
+	if harRequest.PostData != nil && strings.HasPrefix(harRequest.PostData.MimeType, "application/grpc") {
+		// Force HTTP/2 gRPC into HAR template
+
+		harRequest.URL = fmt.Sprintf("%s://%s%s", request.Header.Get(":scheme"), request.Header.Get(":authority"), request.Header.Get(":path"))
+
+		status, err := strconv.Atoi(response.Header.Get(":status"))
+		if err != nil {
+			SilentError("convert-response-status-for-har", "Failed converting status to int %s (%v,%+v)\n", err, err, err)
+			return nil, errors.New("Failed converting response status to int for HAR")
+		}
+		harResponse.Status = status
+	} else {
+		// Martian copies http.Request.URL.String() to har.Request.URL, which usually contains the path.
+		// However, according to the HAR spec, the URL field needs to be the absolute URL.
+		var scheme string
+		if request.URL.Scheme != "" {
+			scheme = request.URL.Scheme
+		} else {
+			scheme = "http"
+		}
+		harRequest.URL = fmt.Sprintf("%s://%s%s", scheme, request.Host, request.URL)
+	}
+
 	totalTime := responseTime.Sub(requestTime).Round(time.Millisecond).Milliseconds()
 	if totalTime < 1 {
 		totalTime = 1