BlobOutput Interface


Place this on a parameter whose value would be written to a blob. The parameter type should be OutputBinding, where T could be one of:

  • Any native Java types such as int, String, byte[]
  • Any POJO type

The following example shows blob input and output bindings in a Java function. The function makes a copy of a text blob. The function is triggered by a queue message that contains the name of the blob to copy. The new blob is named {originalblobname}-Copy.

@BlobOutput(name = "target", path = "samples-workitems/{queueTrigger}-Copy")
 public String blobCopy(
    @QueueTrigger(name = "filename",
                   queueName = "myqueue-items") String filename,
    @BlobInput(name = "source",
                path = "samples-workitems/{queueTrigger}") String content
 ) {
     return content;
public interface BlobOutput implements Annotation



Defines the app setting name that contains the Azure Storage connection string.


Defines how Functions runtime should treat the parameter value. Possible values are:

  • "" or string: treat it as a string whose value is serialized from the parameter
  • binary: treat it as a binary data whose value comes from for example OutputBinding<byte[]>

The variable name used in function.json.


Defines the path of the blob to which to write.

Applies to