(Objective-C) Azure Service Bus - Read Queued Message

See more Azure Service Bus Examples

Demonstrates read a message from an Azure Service Bus Queue. The message is received and removed from the queue.

For more information, see https://docs.microsoft.com/en-us/rest/api/servicebus/receive-and-delete-message-destructive-read

Chilkat Objective-C Library Downloads MAC OS X (Cocoa) Libs iOS Libs

#import <CkoRest.h>
#import <NSString.h>
#import <CkoStringBuilder.h>

// Note: Requires Chilkat v9.5.0.65 or greater.

// This requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

// Make the initial connection.
// A single REST object, once connected, can be used for many Azure Service Bus REST API calls.
// The auto-reconnect indicates that if the already-established HTTPS connection is closed,
// then it will be automatically re-established as needed.
CkoRest *rest = [[CkoRest alloc] init];
BOOL bAutoReconnect = YES;
BOOL success = [rest Connect: @"<yournamespace>.servicebus.windows.net" port: [NSNumber numberWithInt: 443] tls: YES autoReconnect: bAutoReconnect];
if (success != YES) {
    NSLog(@"%@",rest.LastErrorText);
    return;
}

// ----------------------------------------------------------------------------------------------
// The code above this comment could be placed inside a function/subroutine within the application
// because the connection does not need to be made for every request.  Once the connection is made
// the app may send many requests..
// ----------------------------------------------------------------------------------------------

// Receive and delete a message from a queue named "gila";
NSString *queueName = @"gila";

// Let's load a previously computed SAS token and use it.
// See Azure Shared Access Signature for an example to genenerate an Azure SAS token.
CkoStringBuilder *sbToken = [[CkoStringBuilder alloc] init];
[sbToken LoadFile: @"qa_data/tokens/serviceBusSas.txt" charset: @"utf-8"];

// Tell the REST object to use the Azure Shared Access Signature for authorization.
[sbToken Prepend: @"SharedAccessSignature "];
[rest AddHeader: @"Authorization" value: [sbToken GetAsString]];

// Build the path..
CkoStringBuilder *sbPath = [[CkoStringBuilder alloc] init];
[sbPath Append: @"/"];
[sbPath Append: queueName];
[sbPath Append: @"/messages/head"];

// Add timeout and api-version query parameters.
[rest AddQueryParam: @"timeout" value: @"20"];
[rest AddQueryParam: @"api-version" value: @"2013-08"];

// Use the DELETE HTTP verb to read the message at the head of the queue and remove it.
CkoStringBuilder *sbResponseBody = [[CkoStringBuilder alloc] init];
success = [rest FullRequestNoBodySb: @"DELETE" uriPath: [sbPath GetAsString] sb: sbResponseBody];
if (success != YES) {
    NSLog(@"%@",rest.LastErrorText);
    return;
}

NSLog(@"%@%d",@"Response Status Code = ",[rest.ResponseStatusCode intValue]);

// Check for a success response.
if ([rest.ResponseStatusCode intValue] != 200) {
    NSLog(@"%@",rest.LastRequestStartLine);
    NSLog(@"%@",rest.LastRequestHeader);
    NSLog(@"%@",[sbResponseBody GetAsString]);
    NSLog(@"%@",@"Failed.");
    return;
}

// If successful, the message is the contents of the response body.
NSString *message = [sbResponseBody GetAsString];
NSLog(@"%@%@",@"Dequeued message: ",message);

NSLog(@"%@",@"Success.");