User agent string support

2 files changed, 62 insertions, 1 deletions

diff --git a/src/core/channel/http_client_filter.c b/src/core/channel/http_client_filter.c
index 63e4912397..bc821b16fa 100644
--- a/src/core/channel/http_client_filter.c
+++ b/src/core/channel/http_client_filter.c
@@ -32,13 +32,17 @@
 
 #include "src/core/channel/http_client_filter.h"
 #include <string.h>
+#include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+#include "src/core/support/string.h"
 
 typedef struct call_data {
   grpc_linked_mdelem method;
   grpc_linked_mdelem scheme;
   grpc_linked_mdelem te_trailers;
   grpc_linked_mdelem content_type;
+  grpc_linked_mdelem user_agent;
   int sent_initial_metadata;
 
   int got_initial_metadata;
@@ -58,6 +62,8 @@ typedef struct channel_data {
   grpc_mdelem *scheme;
   grpc_mdelem *content_type;
   grpc_mdelem *status;
+  /** complete user agent mdelem */
+  grpc_mdelem *user_agent;
 } channel_data;
 
 /* used to silence 'variable not used' warnings */
@@ -115,6 +121,8 @@ static void hc_mutate_op(grpc_call_element *elem,
                                    GRPC_MDELEM_REF(channeld->te_trailers));
       grpc_metadata_batch_add_tail(&op->data.metadata, &calld->content_type,
                                    GRPC_MDELEM_REF(channeld->content_type));
+      grpc_metadata_batch_add_tail(&op->data.metadata, &calld->user_agent,
+                                   GRPC_MDELEM_REF(channeld->user_agent));
       break;
     }
   }
@@ -169,6 +177,55 @@ static const char *scheme_from_args(const grpc_channel_args *args) {
   return "http";
 }
 
+static grpc_mdstr *user_agent_from_args(grpc_mdctx *mdctx,
+                                        const grpc_channel_args *args) {
+  gpr_strvec v;
+  size_t i;
+  int is_first = 1;
+  char *tmp;
+  grpc_mdstr *result;
+
+  gpr_strvec_init(&v);
+
+  for (i = 0; args && i < args->num_args; i++) {
+    if (0 == strcmp(args->args[i].key, GRPC_ARG_PRIMARY_USER_AGENT_STRING)) {
+      if (args->args[i].type != GRPC_ARG_STRING) {
+        gpr_log(GPR_ERROR, "Channel argument '%s' should be a string",
+                GRPC_ARG_PRIMARY_USER_AGENT_STRING);
+      } else {
+        if (!is_first) gpr_strvec_add(&v, gpr_strdup(" "));
+        is_first = 0;
+        gpr_strvec_add(&v, gpr_strdup(args->args[i].value.string));
+      }
+    }
+  }
+
+  gpr_asprintf(&tmp, "%sgrpc-c/%s (%s)", is_first ? "" : " ",
+               grpc_version_string(), GPR_PLATFORM_STRING);
+  is_first = 0;
+  gpr_strvec_add(&v, tmp);
+
+  for (i = 0; args && i < args->num_args; i++) {
+    if (0 == strcmp(args->args[i].key, GRPC_ARG_SECONDARY_USER_AGENT_STRING)) {
+      if (args->args[i].type != GRPC_ARG_STRING) {
+        gpr_log(GPR_ERROR, "Channel argument '%s' should be a string",
+                GRPC_ARG_SECONDARY_USER_AGENT_STRING);
+      } else {
+        if (!is_first) gpr_strvec_add(&v, gpr_strdup(" "));
+        is_first = 0;
+        gpr_strvec_add(&v, gpr_strdup(args->args[i].value.string));
+      }
+    }
+  }
+
+  tmp = gpr_strvec_flatten(&v, NULL);
+  gpr_strvec_destroy(&v);
+  result = grpc_mdstr_from_string(mdctx, tmp);
+  gpr_free(tmp);
+
+  return result;
+}
+
 /* Constructor for channel_data */
 static void init_channel_elem(grpc_channel_element *elem, grpc_channel *master,
                               const grpc_channel_args *args, grpc_mdctx *mdctx,
@@ -189,6 +246,9 @@ static void init_channel_elem(grpc_channel_element *elem, grpc_channel *master,
   channeld->content_type =
       grpc_mdelem_from_strings(mdctx, "content-type", "application/grpc");
   channeld->status = grpc_mdelem_from_strings(mdctx, ":status", "200");
+  channeld->user_agent = grpc_mdelem_from_metadata_strings(
+      mdctx, grpc_mdstr_from_string(mdctx, "user-agent"),
+      user_agent_from_args(mdctx, args));
 }
 
 /* Destructor for channel data */
@@ -201,6 +261,7 @@ static void destroy_channel_elem(grpc_channel_element *elem) {
   GRPC_MDELEM_UNREF(channeld->scheme);
   GRPC_MDELEM_UNREF(channeld->content_type);
   GRPC_MDELEM_UNREF(channeld->status);
+  GRPC_MDELEM_UNREF(channeld->user_agent);
 }
 
 const grpc_channel_filter grpc_http_client_filter = {
diff --git a/src/core/transport/chttp2/parsing.c b/src/core/transport/chttp2/parsing.c
index aa32f2e44a..904b9afce7 100644
--- a/src/core/transport/chttp2/parsing.c
+++ b/src/core/transport/chttp2/parsing.c
@@ -588,7 +588,7 @@ static void on_header(void *tp, grpc_mdelem *md) {
   GPR_ASSERT(stream_parsing);
 
   GRPC_CHTTP2_IF_TRACING(gpr_log(
-      GPR_INFO, "HTTP:%d:HDR: %s: %s", stream_parsing->id,
+      GPR_INFO, "HTTP:%d:HDR:%s: %s: %s", stream_parsing->id,
       transport_parsing->is_client ? "CLI" : "SVR",
       grpc_mdstr_as_c_string(md->key), grpc_mdstr_as_c_string(md->value)));