Client-side logging with the Azure Storage client library for Java

For instructions on how to install the binaries for the Azure Storage client libraries in your Java project, see the readme file for the project on GitHub: This file documents any additional dependencies you must install.

You must install the optional SLF4J dependency if you are planning to use client-side logging. SLF4J is a logging fa├žade that enables you to use many common Java logging frameworks easily from a client application: for more information about SLF4J, see the SLF4J user manual. For a simple test of how to use SLF4J with the storage SDK, place the slf4j-api and slf4j-simple JAR files in the build path for your storage client project. All storage log messages are subsequently directed to the console.

The following sample Java code shows how to switch storage client logging off by default by calling the static method setLoggingEnabledByDefault, and then use an OperationContext object to enable logging for a specific request:

// Set logging off by default.  
OperationContext ctx = new OperationContext();  
// Create an operation to add a new customer to the people table.  
TableOperation insertCustomer1 = TableOperation.insertOrReplace(customer1);  
// Submit the operation to the table service.  
table.execute(insertCustomer1, null, ctx);  

The following example shows the log messages that slf4j-simple writes to the console:

[main] INFO ROOT - {ceba5ec6...}: {Starting operation.}  
[main] INFO ROOT - {ceba5ec6...}: {Starting operation with location 'PRIMARY' per location mode 'PRIMARY_ONLY'.}  
[main] INFO ROOT - {ceba5ec6...}: {Starting request to ''Harp',RowKey='Walter')' at 'Tue, 08 Jul 2014 15:07:43 GMT'.}  
[main] INFO ROOT - {ceba5ec6...}: {Writing request data.}  
[main] INFO ROOT - {ceba5ec6...}: {Request data was written successfully.}  
[main] INFO ROOT - {ceba5ec6...}: {Waiting for response.}  
[main] INFO ROOT - {ceba5ec6...}: {Response received. Status code = '204', Request ID = '8f6ce566-3760-4733-a8da-a090e642286a', Content-MD5 = 'null', ETag = 'W/"datetime'2014-07-08T15%3A07%3A41.1177234Z'"'.}  
[main] INFO ROOT - {ceba5ec6...}: {Processing response headers.}  
[main] INFO ROOT - {ceba5ec6...}: {Response headers were processed successfully.}  
[main] INFO ROOT - {ceba5ec6...}: {Processing response body.}  
[main] INFO ROOT - {ceba5ec6...}: {Response body was parsed successfully.}  
[main] INFO ROOT - {ceba5ec6...}: {Operation completed.}  

The GUID (ceba5ec6... in the sample) is the client request ID assigned to the storage operation by the client-side storage library.