Improve stream example

amqp-node · Jun 12, 2023 · e9f3034 · e9f3034
1 parent 072ca61
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diff --git a/examples/stream_queues/README.md b/examples/stream_queues/README.md
@@ -6,10 +6,35 @@ These examples show how to use stream queues with the lib.
 
 Send a message to a stream queue
 ```
-./send_stream.js   
+node send_stream.js
 ```
 
 Receive all the messages from stream queue:
 ```
-./receive_stream.js 
-```
+node receive_stream.js
+```
+
+Consumers can be configured to receive messages using an offset via the `x-stream-offset` argument. e.g.
+
+```js
+channel.consume(queue, onMessage, {
+  noAck: false,
+  arguments: {
+    'x-stream-offset': 'first'
+  }
+});
+```
+
+RabbitMQ supports six different types of offset, however specifying them can be
+
+| Offset Type | Example Value                                                  | Notes |
+|-----------|------------------------------------------------------------------|-------|
+| First     | `{ 'x-stream-offset': 'first' }`                                 | Start from the first message in the log |
+| Last      | `{ 'x-stream-offset': 'last' }`                                  | Start from the last "chunk" of messages (could be multiple messages) |
+| Next      | `{ 'x-stream-offset': 'next' }`                                  | Start from the next message (the default) |
+| Offset    | `{ 'x-stream-offset': 5 }`                                       | a numerical value specifying an exact offset to attach to the log at |
+| Timestamp | `{ 'x-stream-offset': { '!': 'timestamp', value: 1686519750 } }` | a timestamp value specifying the point in time to attach to the log at. The timestamp must be the number of seconds since 00:00:00 UTC, 1970-01-01. Consumers can receive messages published a bit before the specified timestamp. |
+| Interval  | `{ 'x-stream-offset': '1h' }`                                    | the time interval relative to current time to attach the log at. Valid units are Y, M, D, h, m and s |
+
+
+See https://www.rabbitmq.com/streams.html#consuming for more details
diff --git a/examples/stream_queues/receive_stream.js b/examples/stream_queues/receive_stream.js
@@ -29,15 +29,17 @@ const amqp = require('amqplib');
             noAck: false,
             arguments: {
                 /*
-                    Here you can specify the offset: : first, last, next, offset and timestamp, i.e.
+                    Here you can specify the offset: : first, last, next, offset, timestamp and interval, i.e.
 
                     'x-stream-offset': 'first'
                     'x-stream-offset': 'last'
                     'x-stream-offset': 'next'
                     'x-stream-offset': 5
                     'x-stream-offset': { '!': 'timestamp', value: 1686519750 }
+                    'x-stream-offset': '1h'
 
                     The timestamp must be the desired number of seconds since 00:00:00 UTC, 1970-01-01
+                    The interval units can be Y, M, D, h, m, s
 
                 */
                 'x-stream-offset': 'first'