Page Comparison

...

• Request method and URI
  • POST [base_url]/topics/[topic]/publish
• Request body

  • JSON object containing payload and optionally transaction write pointer

    { "payload" : [ payload byte array ], "tx_write_ptr" : 12345L,  "buffer" : true }

    Fields:
    i) payload - Contains the payload in the form of array of bytes
    ii) tx_write_ptr (optional) - Contains a long that corresponds to a transaction write pointer. If this field is not provided, then the publishing of message is performed non-transactionally
    iii) buffer (optional) - A boolean flag that indicates whether the messages can be buffered on the client side or should it the message be persisted in a Payload table. This option is not used when tx_write_ptr is not set (i.e., if the message is published non-transactionally)
     

• Response :
  404 NOT FOUND if topic is not present
  200 OK if message is persisted
  
  
• Commit Transactionally published messages
  • POST [base_url]/topics/[topic]/commit

  • Request body should contain the transaction write pointer that should be committed

    { "tx_write_ptr" :  12345L }
    
    Response :

    404 NOT FOUND if topic is not present
    200 OK if messages are persisted

     

• Rollback Transactionally published messages 
  • POST [base_url]/topics/[topic]/rollback

  • Request body should contain the transaction write pointer that should be rolled back

    { "tx_write_ptr" :  12345L }
    
    

    Response :

    404 NOT FOUND if topic is not present
    200 OK if messages are rolled back

    TBD: When or should the client retry? If it could not be rolled back, the transaction should be invalidated.

...

TBD: How should TopicId look like? Should it extend from a NamespaceId and just have a String for the topic?

Creating Topic:
void create(TopicId topic) throws TopicAlreadyExistsException;

Deleting Topic:
void delete(TopicId topic) throws TopicNotFoundException;

Publishing Message: Consuming Message:

For publishing messages non-transactionally:

• void publish(TopicId topic, byte[] payload) throws TopicNotFoundException;

For publishing messages transactionally by providing the Transaction object and as well as a boolean variable that indicates whether the messages should be persisted in the payloadTable before the messages are 

• void publish(TopicId topic, byte[] payload, Transaction transaction, boolean buffer) throws TopicNotFoundException;  

Consuming Message:

For consuming messages non-transactionally:

• List<Message> poll(TopicId topic) throws TopicNotFoundException; 
  
  
• List<Message> poll(TopicId topic, long timestampInMs, boolean inclusive) throws TopicNotFoundException;
  
  
• List<Message> poll(TopicId topic, MessageId messageId, boolean inclusive) throws TopicNotFoundException;
  
  
• List<Message> poll(TopicId topic, long timestampInMs, boolean inclusive, long maxMessages) throws TopicNotFoundException;
  
  
• List<Message> poll(TopicId topic, MessageId, messageId, boolean inclusive, long maxMessages) throws TopicNotFoundException;
  
  class Message {
      MessageId messageId;
      byte[] payload;
  }
  
  class MessageId {
    long publish_timestamp;
    short seq_id;
    long write_timestamp;
    short p_seq_id;
  }