env/rabbitmq-c/examples/amqp_rpc_sendstring_client.c

// Copyright 2007 - 2021, Alan Antonuk and the rabbitmq-c contributors.
// SPDX-License-Identifier: mit

#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <rabbitmq-c/amqp.h>
#include <rabbitmq-c/tcp_socket.h>

#include <assert.h>

#include "utils.h"

int main(int argc, char *argv[]) {
  char const *hostname;
  int port, status;
  char const *exchange;
  char const *routingkey;
  char const *messagebody;
  amqp_socket_t *socket = NULL;
  amqp_connection_state_t conn;
  amqp_bytes_t reply_to_queue;

  if (argc < 6) { /* minimum number of mandatory arguments */
    fprintf(stderr,
            "usage:\namqp_rpc_sendstring_client host port exchange routingkey "
            "messagebody\n");
    return 1;
  }

  hostname = argv[1];
  port = atoi(argv[2]);
  exchange = argv[3];
  routingkey = argv[4];
  messagebody = argv[5];

  /*
     establish a channel that is used to connect RabbitMQ server
  */

  conn = amqp_new_connection();

  socket = amqp_tcp_socket_new(conn);
  if (!socket) {
    die("creating TCP socket");
  }

  status = amqp_socket_open(socket, hostname, port);
  if (status) {
    die("opening TCP socket");
  }

  die_on_amqp_error(amqp_login(conn, "/", 0, 131072, 0, AMQP_SASL_METHOD_PLAIN,
                               "guest", "guest"),
                    "Logging in");
  amqp_channel_open(conn, 1);
  die_on_amqp_error(amqp_get_rpc_reply(conn), "Opening channel");

  /*
     create private reply_to queue
  */

  {
    amqp_queue_declare_ok_t *r = amqp_queue_declare(
        conn, 1, amqp_empty_bytes, 0, 0, 0, 1, amqp_empty_table);
    die_on_amqp_error(amqp_get_rpc_reply(conn), "Declaring queue");
    reply_to_queue = amqp_bytes_malloc_dup(r->queue);
    if (reply_to_queue.bytes == NULL) {
      fprintf(stderr, "Out of memory while copying queue name");
      return 1;
    }
  }

  /*
     send the message
  */

  {
    /*
      set properties
    */
    amqp_basic_properties_t props;
    props._flags = AMQP_BASIC_CONTENT_TYPE_FLAG |
                   AMQP_BASIC_DELIVERY_MODE_FLAG | AMQP_BASIC_REPLY_TO_FLAG |
                   AMQP_BASIC_CORRELATION_ID_FLAG;
    props.content_type = amqp_cstring_bytes("text/plain");
    props.delivery_mode = 2; /* persistent delivery mode */
    props.reply_to = amqp_bytes_malloc_dup(reply_to_queue);
    if (props.reply_to.bytes == NULL) {
      fprintf(stderr, "Out of memory while copying queue name");
      return 1;
    }
    props.correlation_id = amqp_cstring_bytes("1");

    /*
      publish
    */
    die_on_error(amqp_basic_publish(conn, 1, amqp_cstring_bytes(exchange),
                                    amqp_cstring_bytes(routingkey), 0, 0,
                                    &props, amqp_cstring_bytes(messagebody)),
                 "Publishing");

    amqp_bytes_free(props.reply_to);
  }

  /*
    wait an answer
  */

  {
    amqp_basic_consume(conn, 1, reply_to_queue, amqp_empty_bytes, 0, 1, 0,
                       amqp_empty_table);
    die_on_amqp_error(amqp_get_rpc_reply(conn), "Consuming");
    amqp_bytes_free(reply_to_queue);

    {
      amqp_frame_t frame;
      int result;

      amqp_basic_deliver_t *d;
      amqp_basic_properties_t *p;
      size_t body_target;
      size_t body_received;

      for (;;) {
        amqp_maybe_release_buffers(conn);
        result = amqp_simple_wait_frame(conn, &frame);
        printf("Result: %d\n", result);
        if (result < 0) {
          break;
        }

        printf("Frame type: %u channel: %u\n", frame.frame_type, frame.channel);
        if (frame.frame_type != AMQP_FRAME_METHOD) {
          continue;
        }

        printf("Method: %s\n", amqp_method_name(frame.payload.method.id));
        if (frame.payload.method.id != AMQP_BASIC_DELIVER_METHOD) {
          continue;
        }

        d = (amqp_basic_deliver_t *)frame.payload.method.decoded;
        printf("Delivery: %u exchange: %.*s routingkey: %.*s\n",
               (unsigned)d->delivery_tag, (int)d->exchange.len,
               (char *)d->exchange.bytes, (int)d->routing_key.len,
               (char *)d->routing_key.bytes);

        result = amqp_simple_wait_frame(conn, &frame);
        if (result < 0) {
          break;
        }

        if (frame.frame_type != AMQP_FRAME_HEADER) {
          fprintf(stderr, "Expected header!");
          abort();
        }
        p = (amqp_basic_properties_t *)frame.payload.properties.decoded;
        if (p->_flags & AMQP_BASIC_CONTENT_TYPE_FLAG) {
          printf("Content-type: %.*s\n", (int)p->content_type.len,
                 (char *)p->content_type.bytes);
        }
        printf("----\n");

        body_target = (size_t)frame.payload.properties.body_size;
        body_received = 0;

        while (body_received < body_target) {
          result = amqp_simple_wait_frame(conn, &frame);
          if (result < 0) {
            break;
          }

          if (frame.frame_type != AMQP_FRAME_BODY) {
            fprintf(stderr, "Expected body!");
            abort();
          }

          body_received += frame.payload.body_fragment.len;
          assert(body_received <= body_target);

          amqp_dump(frame.payload.body_fragment.bytes,
                    frame.payload.body_fragment.len);
        }

        if (body_received != body_target) {
          /* Can only happen when amqp_simple_wait_frame returns <= 0 */
          /* We break here to close the connection */
          break;
        }

        /* everything was fine, we can quit now because we received the reply */
        break;
      }
    }
  }

  /*
     closing
  */

  die_on_amqp_error(amqp_channel_close(conn, 1, AMQP_REPLY_SUCCESS),
                    "Closing channel");
  die_on_amqp_error(amqp_connection_close(conn, AMQP_REPLY_SUCCESS),
                    "Closing connection");
  die_on_error(amqp_destroy_connection(conn), "Ending connection");

  return 0;
}