mobile: Add respones codes to the error details

The HTTP response code is not reported in the Cronvoy exceptions, and
the error_code, which maps from some small subset of response codes to
envoy_error_code_t, is not used in the onError functions. As a first
step, we want to append the HTTP response code and the Envoy error code
to the error details.

A subsequent PR will add more support for mapping Http::Code to
envoy_error_code_t (or getting rid of envoy_error_code_t all together).

Signed-off-by: Ali Beyad <abeyad@google.com>

mobile/library/common/http/client.cc

@@ -7,6 +7,8 @@
 #include "source/common/http/headers.h"
 #include "source/common/http/utility.h"
 
+#include "absl/strings/str_cat.h"
+#include "absl/strings/str_join.h"
 #include "library/common/bridge/utility.h"
 #include "library/common/data/utility.h"
 #include "library/common/http/header_utility.h"
@@ -437,16 +439,27 @@ void Client::DirectStreamCallbacks::latchError() {
   }
   const auto& info = request_decoder->streamInfo();
 
+  std::vector<std::string> error_msg_details;
   if (info.responseCode().has_value()) {
     error_->error_code = Bridge::Utility::errorCodeFromLocalStatus(
         static_cast<Http::Code>(info.responseCode().value()));
+    error_msg_details.push_back(absl::StrCat("RC: ", info.responseCode().value()));
   } else if (StreamInfo::isStreamIdleTimeout(info)) {
     error_->error_code = ENVOY_REQUEST_TIMEOUT;
   } else {
     error_->error_code = ENVOY_STREAM_RESET;
   }
 
-  error_->message = info.responseCodeDetails().value_or("");
+  error_msg_details.push_back(absl::StrCat("EC: ", error_->error_code));
+  if (info.responseCodeDetails().has_value()) {
+    error_msg_details.push_back(info.responseCodeDetails().value());
+  }
+  // The format of the error message propogated to callbacks is:
+  //  {RESPONSE_CODE}|{ERROR_CODE}|{DETAILS}
+  // Where RESPONSE_CODE is the HTTP response code from StreamInfo::responseCode().
+  // ERROR_CODE is of the envoy_error_code_t enum type, and gets mapped from RESPONSE_CODE.
+  // DETAILS is the contents of StreamInfo::responseCodeDetails().
+  error_->message = absl::StrJoin(std::move(error_msg_details), "|");
   error_->attempt_count = info.attemptCount().value_or(0);
 }
 

mobile/test/common/http/client_test.cc

@@ -21,6 +21,7 @@
 
 using testing::_;
 using testing::AnyNumber;
+using testing::ContainsRegex;
 using testing::NiceMock;
 using testing::Return;
 using testing::ReturnPointee;
@@ -444,6 +445,7 @@ TEST_P(ClientTest, EnvoyLocalError) {
   stream_callbacks.on_error_ = [&](EnvoyError error, envoy_stream_intel,
                                    envoy_final_stream_intel) -> void {
     EXPECT_EQ(error.error_code, ENVOY_CONNECTION_FAILURE);
+    EXPECT_THAT(error.message, ContainsRegex("503|2|failed miserably"));
     EXPECT_EQ(error.attempt_count, 123);
     callbacks_called.on_error_calls_++;
   };
@@ -463,7 +465,7 @@ TEST_P(ClientTest, EnvoyLocalError) {
   EXPECT_CALL(dispatcher_, popTrackedObject(_));
   EXPECT_CALL(dispatcher_, deferredDelete_(_));
   stream_info_.setResponseCode(503);
-  stream_info_.setResponseCodeDetails("nope");
+  stream_info_.setResponseCodeDetails("failed miserably");
   stream_info_.setAttemptCount(123);
   response_encoder_->getStream().resetStream(Http::StreamResetReason::LocalConnectionFailure);
   ASSERT_EQ(callbacks_called.on_headers_calls_, 0);
@@ -518,7 +520,7 @@ TEST_P(ClientTest, RemoteResetAfterStreamStart) {
   stream_callbacks.on_error_ = [&](EnvoyError error, envoy_stream_intel,
                                    envoy_final_stream_intel) -> void {
     EXPECT_EQ(error.error_code, ENVOY_STREAM_RESET);
-    EXPECT_EQ(error.message.length(), 0);
+    EXPECT_THAT(error.message, ContainsRegex("1"));
     EXPECT_EQ(error.attempt_count, 0);
     callbacks_called.on_error_calls_++;
   };