Peek Messages operation retrieves one or more messages from the front of the queue, but it doesn't alter the visibility of the message.
You can construct the
Peek Messages request as follows. We recommend that you use HTTPS. Replace myaccount with the name of your storage account, and replace myqueue with the name of your queue:
|Method||Request URI||HTTP version|
Emulated storage service request
When you're making a request against the emulated storage service, specify the emulator hostname and Queue service port as
127.0.0.1:10001, followed by the emulated storage account name:
|Method||Request URI||HTTP version|
For more information, see Use the Azurite emulator for local Azure Storage development.
The following parameters may be specified on the request URI.
||Optional. A nonzero integer value that specifies the number of messages to peek from the queue, up to a maximum of 32. By default, a single message is peeked from the queue with this operation.|
The required and optional request headers are described in the following table:
||Required. Specifies the authorization scheme, account name, and signature. For more information, see Authorize requests to Azure Storage.|
||Required. Specifies the Coordinated Universal Time (UTC) for the request. For more information, see Authorize requests to Azure Storage.|
||Optional. Specifies the version of the operation to use for this request. For more information, see Versioning for the Azure Storage services.|
||Optional. Provides a client-generated, opaque value with a 1-kibibyte (KiB) character limit that's recorded in the logs when logging is configured. We highly recommend that you use this header to correlate client-side activities with requests that the server receives. For more information, see Monitor Azure Queue Storage.|
The response includes an HTTP status code, a set of response headers, and an XML response body.
A successful operation returns status code 200 (OK).
For more information about status codes, see Status and error codes.
The response for this operation includes the following headers. The response also includes additional standard HTTP headers. All standard headers conform to the HTTP/1.1 protocol specification.
||Uniquely identifies the request that was made, and you can use it to troubleshoot the request. For more information, see Troubleshoot API operations.|
||The Queue service version that was used to execute the request. Returned for requests that were made against version 2009-09-19 and later.|
||A UTC date/time value that's generated by the service, which indicates the time when the response was initiated.|
||Can be used to troubleshoot requests and their corresponding responses. The value of this header is equal to the value of the
The response XML for the
Peek Messages operation is returned in the following format.
MessageID element is a GUID value that identifies the message in the queue. This value is assigned to the message by the Queue service and is opaque to the client.
ExpirationTime elements are represented as UTC values and formatted as described in RFC 1123.
DequeueCount element has a value of 1 the first time the message is dequeued. This value is incremented each time the message is subsequently dequeued.
DequeueCount element is returned in the response body only if the queue was created with Queue service version 2009-09-19.
<QueueMessagesList> <QueueMessage> <MessageId>string-message-id</MessageId> <InsertionTime>insertion-time</InsertionTime> <ExpirationTime>expiration-time</ExpirationTime> <DequeueCount>integer</DequeueCount> <MessageText>message-body</MessageText> </QueueMessage> </QueueMessagesList>
This response differs from the response for the Get Messages operation in that it doesn't contain the
Response Status: HTTP/1.1 200 OK Response Headers: Transfer-Encoding: chunked Content-Type: application/xml Date: Fri, 16 Sep 2011 22:51:18 GMT Server: Windows-Azure-Queue/1.0 Microsoft-HTTPAPI/2.0 Response Body: <?xml version="1.0" encoding="utf-8"?> <QueueMessagesList> <QueueMessage> <MessageId>06eba214-8107-4412-a7f6-710a9baff647</MessageId> <InsertionTime>Fri, 09 Oct 2009 18:59:54 GMT</InsertionTime> <ExpirationTime>Fri, 16 Sep 2009 18:59:54 GMT</ExpirationTime> <DequeueCount>1</DequeueCount> <MessageText>PHRlc3Q+dGhpcyBpcyBhIHRlc3QgbWVzc2FnZTwvdGVzdD4=</MessageText> </QueueMessage> </QueueMessagesList>
This operation can be performed by the account owner and by anyone with a shared access signature who has permission to perform this operation.
When a message is retrieved from the queue with
peekonly set to
true, the visibility of the message is unchanged. The message remains available to other consumers of the queue until a client retrieves the message by using the Get Messages operation. The client that requests the message doesn't receive a pop receipt with the response and, therefore, can't delete the message.
Only messages that are visible can be retrieved with the
Peek Messages operation. Note that the maximum number of messages that can be retrieved is 32.
When a message is retrieved for the first time with a call to
Get Messages, its
DequeueCount property is set to 1. If it isn't deleted and is subsequently retrieved again, the
DequeueCount property is incremented. The client can use this value to determine how many times a message has been retrieved.
A call to
Peek Messages doesn't increment the value of
DequeueCount, but it returns this value for the client to read.
If the numofmessages parameter is out of range, the service returns status code 400 (Bad Request), along with additional error information, as shown in the following example:
HTTP/1.1 400 One of the query parameters specified in the request URI is outside the permissible range. Connection: Keep-Alive Content-Length: 455 Via: 1.1 TK5-PRXY-22 Date: Wed, 02 May 2012 19:37:23 GMT Content-Type: application/xml Server: Windows-Azure-Queue/1.0 Microsoft-HTTPAPI/2.0 x-ms-request-id: 6a03526c-ca2c-4358-a63a-b5d096988533 x-ms-version: 2011-08-18 <?xml version="1.0" encoding="utf-8"?> <Error> <Code>OutOfRangeQueryParameterValue</Code> <Message>One of the query parameters specified in the request URI is outside the permissible range. RequestId:6a03526c-ca2c-4358-a63a-b5d096988533 Time:2012-05-02T19:37:24.2438463Z </Message> <QueryParameterName>numofmessages</QueryParameterName> <QueryParameterValue>0</QueryParameterValue> <MinimumAllowed>1</MinimumAllowed> <MaximumAllowed>32</MaximumAllowed> </Error>