src/core/httpcli/httpcli.c

/*
 *
 * 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/iomgr/sockaddr.h"
#include "src/core/httpcli/httpcli.h"

#include <string.h>

#include "src/core/iomgr/endpoint.h"
#include "src/core/iomgr/resolve_address.h"
#include "src/core/iomgr/tcp_client.h"
#include "src/core/httpcli/format_request.h"
#include "src/core/httpcli/parser.h"
#include "src/core/support/string.h"
#include <grpc/support/alloc.h>
#include <grpc/support/log.h>
#include <grpc/support/string_util.h>

typedef struct
{
  gpr_slice request_text;
  grpc_httpcli_parser parser;
  grpc_resolved_addresses *addresses;
  size_t next_address;
  grpc_endpoint *ep;
  char *host;
  gpr_timespec deadline;
  int have_read_byte;
  const grpc_httpcli_handshaker *handshaker;
  grpc_httpcli_response_cb on_response;
  void *user_data;
  grpc_httpcli_context *context;
  grpc_pollset *pollset;
  grpc_iomgr_object iomgr_obj;
  gpr_slice_buffer incoming;
  gpr_slice_buffer outgoing;
  grpc_closure on_read;
  grpc_closure done_write;
  grpc_closure connected;
} internal_request;

static grpc_httpcli_get_override g_get_override = NULL;
static grpc_httpcli_post_override g_post_override = NULL;

static void
plaintext_handshake (void *arg, grpc_endpoint * endpoint, const char *host, void (*on_done) (grpc_exec_ctx * exec_ctx, void *arg, grpc_endpoint * endpoint, grpc_closure_list * closure_list))
{
  on_done (exec_ctx, arg, endpoint);
}

const grpc_httpcli_handshaker grpc_httpcli_plaintext = { "http",
  plaintext_handshake
};

void
grpc_httpcli_context_init (grpc_httpcli_context * context)
{
  grpc_pollset_set_init (&context->pollset_set);
}

void
grpc_httpcli_context_destroy (grpc_httpcli_context * context)
{
  grpc_pollset_set_destroy (&context->pollset_set);
}

static void next_address (grpc_exec_ctx * exec_ctx, internal_request * req);

static void
finish (grpc_exec_ctx * exec_ctx, internal_request * req, int success)
{
  grpc_pollset_set_del_pollset (exec_ctx, &req->context->pollset_set, req->pollset);
  req->on_response (exec_ctx, req->user_data, success ? &req->parser.r : NULL);
  grpc_httpcli_parser_destroy (&req->parser);
  if (req->addresses != NULL)
    {
      grpc_resolved_addresses_destroy (req->addresses);
    }
  if (req->ep != NULL)
    {
      grpc_endpoint_destroy (exec_ctx, req->ep);
    }
  gpr_slice_unref (req->request_text);
  gpr_free (req->host);
  grpc_iomgr_unregister_object (&req->iomgr_obj);
  gpr_slice_buffer_destroy (&req->incoming);
  gpr_slice_buffer_destroy (&req->outgoing);
  gpr_free (req);
}

static void on_read (grpc_exec_ctx * exec_ctx, void *user_data, int success);

static void
do_read (grpc_exec_ctx * exec_ctx, internal_request * req)
{
  grpc_endpoint_read (exec_ctx, req->ep, &req->incoming, &req->on_read);
}

static void
on_read (grpc_exec_ctx * exec_ctx, void *user_data, int success)
{
  internal_request *req = user_data;
  size_t i;

  for (i = 0; i < req->incoming.count; i++)
    {
      if (GPR_SLICE_LENGTH (req->incoming.slices[i]))
	{
	  req->have_read_byte = 1;
	  if (!grpc_httpcli_parser_parse (&req->parser, req->incoming.slices[i]))
	    {
	      finish (exec_ctx, req, 0);
	      return;
	    }
	}
    }

  if (success)
    {
      do_read (exec_ctx, req);
    }
  else if (!req->have_read_byte)
    {
      next_address (exec_ctx, req);
    }
  else
    {
      finish (req, grpc_httpcli_parser_eof (exec_ctx, &req->parser));
    }
}

static void
on_written (grpc_exec_ctx * exec_ctx, internal_request * req)
{
  do_read (exec_ctx, req);
}

static void
done_write (grpc_exec_ctx * exec_ctx, void *arg, int success)
{
  internal_request *req = arg;
  if (success)
    {
      on_written (exec_ctx, req);
    }
  else
    {
      next_address (exec_ctx, req);
    }
}

static void
start_write (grpc_exec_ctx * exec_ctx, internal_request * req)
{
  gpr_slice_ref (req->request_text);
  gpr_slice_buffer_add (&req->outgoing, req->request_text);
  grpc_endpoint_write (exec_ctx, req->ep, &req->outgoing, &req->done_write);
}

static void
on_handshake_done (grpc_exec_ctx * exec_ctx, void *arg, grpc_endpoint * ep)
{
  internal_request *req = arg;

  if (!ep)
    {
      next_address (exec_ctx, req);
      return;
    }

  req->ep = ep;
  start_write (exec_ctx, req);
}

static void
on_connected (grpc_exec_ctx * exec_ctx, void *arg, int success)
{
  internal_request *req = arg;

  if (!req->ep)
    {
      next_address (exec_ctx, req);
      return;
    }
  req->handshaker->handshake (exec_ctx, req, req->ep, req->host, on_handshake_done);
}

static void
next_address (grpc_exec_ctx * exec_ctx, internal_request * req)
{
  grpc_resolved_address *addr;
  if (req->next_address == req->addresses->naddrs)
    {
      finish (exec_ctx, req, 0);
      return;
    }
  addr = &req->addresses->addrs[req->next_address++];
  grpc_closure_init (&req->connected, on_connected, req);
  grpc_tcp_client_connect (&req->connected, &req->ep, &req->context->pollset_set, (exec_ctx, struct sockaddr *) &addr->addr, addr->len, req->deadline);
}

static void
on_resolved (grpc_exec_ctx * exec_ctx, void *arg, grpc_resolved_addresses * addresses)
{
  internal_request *req = arg;
  if (!addresses)
    {
      finish (exec_ctx, req, 0);
      return;
    }
  req->addresses = addresses;
  req->next_address = 0;
  next_address (exec_ctx, req);
}

static void
internal_request_begin (grpc_exec_ctx * exec_ctx, grpc_httpcli_context * context, grpc_pollset * pollset, const grpc_httpcli_request * request, gpr_timespec deadline, grpc_httpcli_response_cb on_response, void *user_data, const char *name, gpr_slice request_text)
{
  internal_request *req = gpr_malloc (sizeof (internal_request));
  memset (req, 0, sizeof (*req));
  req->request_text = request_text;
  grpc_httpcli_parser_init (&req->parser);
  req->on_response = on_response;
  req->user_data = user_data;
  req->deadline = deadline;
  req->handshaker = request->handshaker ? request->handshaker : &grpc_httpcli_plaintext;
  req->context = context;
  req->pollset = pollset;
  grpc_closure_init (&req->on_read, on_read, req);
  grpc_closure_init (&req->done_write, done_write, req);
  gpr_slice_buffer_init (&req->incoming);
  gpr_slice_buffer_init (&req->outgoing);
  grpc_iomgr_register_object (&req->iomgr_obj, name);
  req->host = gpr_strdup (request->host);

  grpc_pollset_set_add_pollset (exec_ctx, &req->context->pollset_set, req->pollset);
  grpc_resolve_address (request->host, req->handshaker->default_port, on_resolved, req);
}

void
grpc_httpcli_get (grpc_exec_ctx * exec_ctx, grpc_httpcli_context * context, grpc_pollset * pollset, const grpc_httpcli_request * request, gpr_timespec deadline, grpc_httpcli_response_cb on_response, void *user_data)
{
  char *name;
  if (g_get_override && g_get_override (exec_ctx, request, deadline, on_response, user_data))
    {
      return;
    }
  gpr_asprintf (&name, "HTTP:GET:%s:%s", request->host, request->path);
  internal_request_begin (context, pollset, request, deadline, on_response, user_data, name, grpc_httpcli_format_get_request (exec_ctx, request));
  gpr_free (name);
}

void
grpc_httpcli_post (grpc_exec_ctx * exec_ctx, grpc_httpcli_context * context, grpc_pollset * pollset, const grpc_httpcli_request * request, const char *body_bytes, size_t body_size, gpr_timespec deadline, grpc_httpcli_response_cb on_response, void *user_data)
{
  char *name;
  if (g_post_override && g_post_override (exec_ctx, request, body_bytes, body_size, deadline, on_response, user_data))
    {
      return;
    }
  gpr_asprintf (&name, "HTTP:POST:%s:%s", request->host, request->path);
  internal_request_begin (context, pollset, request, deadline, on_response, user_data, name, grpc_httpcli_format_post_request (exec_ctx, request, body_bytes, body_size));
  gpr_free (name);
}

void
grpc_httpcli_set_override (grpc_httpcli_get_override get, grpc_httpcli_post_override post)
{
  g_get_override = get;
  g_post_override = post;
}