65 lines
2.0 KiB
C
65 lines
2.0 KiB
C
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// Copyright 2017-2018 The NATS Authors
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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#include <nats.h>
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int main(int argc, char **argv)
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{
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natsConnection *conn = NULL;
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natsSubscription *sub = NULL;
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natsMsg *msg = NULL;
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natsStatus s;
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printf("Listening on subject 'foo'\n");
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// Creates a connection to the default NATS URL
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s = natsConnection_ConnectTo(&conn, NATS_DEFAULT_URL);
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if (s == NATS_OK)
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{
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// Creates an synchronous subscription on subject "foo".
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s = natsConnection_SubscribeSync(&sub, conn, "foo");
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}
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if (s == NATS_OK)
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{
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// With synchronous subscriptions, one need to poll
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// using this function. A timeout is used to instruct
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// how long we are willing to wait. The wait is in milliseconds.
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// So here, we are going to wait for 5 seconds.
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s = natsSubscription_NextMsg(&msg, sub, 5000);
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}
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if (s == NATS_OK)
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{
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// If we are here, we should have received a message.
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printf("Received msg: %s - %.*s\n",
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natsMsg_GetSubject(msg),
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natsMsg_GetDataLength(msg),
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natsMsg_GetData(msg));
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// Need to destroy the message!
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natsMsg_Destroy(msg);
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}
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// Anything that is created need to be destroyed
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natsSubscription_Destroy(sub);
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natsConnection_Destroy(conn);
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// If there was an error, print a stack trace and exit
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if (s != NATS_OK)
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{
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nats_PrintLastErrorStack(stderr);
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exit(2);
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}
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return 0;
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}
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