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/*
* Copyright 2015, Google Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include "src/core/lib/channel/http_client_filter.h"
#include <grpc/support/alloc.h>
#include <grpc/support/log.h>
#include <grpc/support/string_util.h>
#include <string.h>
#include "src/core/lib/profiling/timers.h"
#include "src/core/lib/support/string.h"
#include "src/core/lib/transport/static_metadata.h"
#include "src/core/lib/transport/transport_impl.h"
typedef struct call_data {
grpc_linked_mdelem method;
grpc_linked_mdelem scheme;
grpc_linked_mdelem authority;
grpc_linked_mdelem te_trailers;
grpc_linked_mdelem content_type;
grpc_linked_mdelem user_agent;
grpc_metadata_batch *recv_initial_metadata;
/** Closure to call when finished with the hc_on_recv hook */
grpc_closure *on_done_recv;
/** Receive closures are chained: we inject this closure as the on_done_recv
up-call on transport_op, and remember to call our on_done_recv member
after handling it. */
grpc_closure hc_on_recv;
} call_data;
typedef struct channel_data {
grpc_mdelem *static_scheme;
grpc_mdelem *user_agent;
} channel_data;
typedef struct {
grpc_call_element *elem;
grpc_exec_ctx *exec_ctx;
} client_recv_filter_args;
static grpc_mdelem *client_recv_filter(void *user_data, grpc_mdelem *md) {
client_recv_filter_args *a = user_data;
if (md == GRPC_MDELEM_STATUS_200) {
return NULL;
} else if (md->key == GRPC_MDSTR_STATUS) {
grpc_call_element_send_cancel(a->exec_ctx, a->elem);
return NULL;
} else if (md->key == GRPC_MDSTR_CONTENT_TYPE) {
return NULL;
}
return md;
}
static void hc_on_recv(grpc_exec_ctx *exec_ctx, void *user_data, bool success) {
grpc_call_element *elem = user_data;
call_data *calld = elem->call_data;
client_recv_filter_args a;
a.elem = elem;
a.exec_ctx = exec_ctx;
grpc_metadata_batch_filter(calld->recv_initial_metadata, client_recv_filter,
&a);
calld->on_done_recv->cb(exec_ctx, calld->on_done_recv->cb_arg, success);
}
static grpc_mdelem *client_strip_filter(void *user_data, grpc_mdelem *md) {
/* eat the things we'd like to set ourselves */
if (md->key == GRPC_MDSTR_METHOD) return NULL;
if (md->key == GRPC_MDSTR_SCHEME) return NULL;
if (md->key == GRPC_MDSTR_TE) return NULL;
if (md->key == GRPC_MDSTR_CONTENT_TYPE) return NULL;
if (md->key == GRPC_MDSTR_USER_AGENT) return NULL;
return md;
}
static void hc_mutate_op(grpc_call_element *elem,
grpc_transport_stream_op *op) {
/* grab pointers to our data from the call element */
call_data *calld = elem->call_data;
channel_data *channeld = elem->channel_data;
if (op->send_initial_metadata != NULL) {
grpc_metadata_batch_filter(op->send_initial_metadata, client_strip_filter,
elem);
/* Send : prefixed headers, which have to be before any application
layer headers. */
grpc_metadata_batch_add_head(
op->send_initial_metadata, &calld->method,
op->send_initial_metadata_flags &
GRPC_INITIAL_METADATA_IDEMPOTENT_REQUEST
? GRPC_MDELEM_METHOD_PUT
: GRPC_MDELEM_METHOD_POST);
grpc_metadata_batch_add_head(op->send_initial_metadata, &calld->scheme,
channeld->static_scheme);
grpc_metadata_batch_add_tail(op->send_initial_metadata, &calld->te_trailers,
GRPC_MDELEM_TE_TRAILERS);
grpc_metadata_batch_add_tail(
op->send_initial_metadata, &calld->content_type,
GRPC_MDELEM_CONTENT_TYPE_APPLICATION_SLASH_GRPC);
grpc_metadata_batch_add_tail(op->send_initial_metadata, &calld->user_agent,
GRPC_MDELEM_REF(channeld->user_agent));
}
if (op->recv_initial_metadata != NULL) {
/* substitute our callback for the higher callback */
calld->recv_initial_metadata = op->recv_initial_metadata;
calld->on_done_recv = op->recv_initial_metadata_ready;
op->recv_initial_metadata_ready = &calld->hc_on_recv;
}
}
static void hc_start_transport_op(grpc_exec_ctx *exec_ctx,
grpc_call_element *elem,
grpc_transport_stream_op *op) {
GPR_TIMER_BEGIN("hc_start_transport_op", 0);
GRPC_CALL_LOG_OP(GPR_INFO, elem, op);
hc_mutate_op(elem, op);
GPR_TIMER_END("hc_start_transport_op", 0);
grpc_call_next_op(exec_ctx, elem, op);
}
/* Constructor for call_data */
static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
grpc_call_element_args *args) {
call_data *calld = elem->call_data;
calld->on_done_recv = NULL;
grpc_closure_init(&calld->hc_on_recv, hc_on_recv, elem);
}
/* Destructor for call_data */
static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
void *ignored) {}
static grpc_mdelem *scheme_from_args(const grpc_channel_args *args) {
unsigned i;
size_t j;
grpc_mdelem *valid_schemes[] = {GRPC_MDELEM_SCHEME_HTTP,
GRPC_MDELEM_SCHEME_HTTPS};
if (args != NULL) {
for (i = 0; i < args->num_args; ++i) {
if (args->args[i].type == GRPC_ARG_STRING &&
strcmp(args->args[i].key, GRPC_ARG_HTTP2_SCHEME) == 0) {
for (j = 0; j < GPR_ARRAY_SIZE(valid_schemes); j++) {
if (0 == strcmp(grpc_mdstr_as_c_string(valid_schemes[j]->value),
args->args[i].value.string)) {
return valid_schemes[j];
}
}
}
}
}
return GRPC_MDELEM_SCHEME_HTTP;
}
static grpc_mdstr *user_agent_from_args(const grpc_channel_args *args,
const char *transport_name) {
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; %s)", is_first ? "" : " ",
grpc_version_string(), GPR_PLATFORM_STRING, transport_name);
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(tmp);
gpr_free(tmp);
return result;
}
/* Constructor for channel_data */
static void init_channel_elem(grpc_exec_ctx *exec_ctx,
grpc_channel_element *elem,
grpc_channel_element_args *args) {
channel_data *chand = elem->channel_data;
GPR_ASSERT(!args->is_last);
GPR_ASSERT(args->optional_transport != NULL);
chand->static_scheme = scheme_from_args(args->channel_args);
chand->user_agent = grpc_mdelem_from_metadata_strings(
GRPC_MDSTR_USER_AGENT,
user_agent_from_args(args->channel_args,
args->optional_transport->vtable->name));
}
/* Destructor for channel data */
static void destroy_channel_elem(grpc_exec_ctx *exec_ctx,
grpc_channel_element *elem) {
channel_data *chand = elem->channel_data;
GRPC_MDELEM_UNREF(chand->user_agent);
}
const grpc_channel_filter grpc_http_client_filter = {
hc_start_transport_op,
grpc_channel_next_op,
sizeof(call_data),
init_call_elem,
grpc_call_stack_ignore_set_pollset,
destroy_call_elem,
sizeof(channel_data),
init_channel_elem,
destroy_channel_elem,
grpc_call_next_get_peer,
"http-client"};
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