The SpPersistentSubscribeSource component subscribes to a stream in Event Stream Processor and sends records on to other components.
ClassName = com.sybase.esp.adapter.asap.SpPersistentSubscribeSource
The stream the component subscribes to does not explicitly remove records until asked by the subscriber. Once records are processed, SpPersistentSubscribeSource publishes tags back to the Event Stream Processor to remove rows from the subscribed stream.
SpPersistentSubscribeSource has two additional streams: log stream and truncate stream. For example, you can have three streams named Stream1, Stream1_log, and Stream1Truncate. The log stream has two additional columns: sequence number and opcode. Records pass from Stream1 to Stream1_log, as well as increasing sequence number values. The opcode values in the opcode column in Stream1_log are "insert". After SpPersistentSubscribeSource subscribes to a batch of data (or a single record), the last sequence number of the records is published to Stream1Truncate, which then removes any records prior to that sequence number from the Stream1_log and persistent store (for example, file on hard disk).
| Property | Description |
|---|---|
| Host | (Required) Host name for the Event Stream Processor command and control process. |
| Port | (Required) Port number for the Event Stream Processor command and control process. |
ProjectUri |
(Dependent required) Connect to the Server running in cluster mode. For example, esp://localost:19011/ws1/p1. |
| IsEncrypted | (Optional) If this property is set to true, AsapSource attempts to use an SSL connection to Event Stream Processor. |
UseServerRSA |
(Optional) If true, server RSA authentication is used to connect to the Server. If you specify this property, also provide the KeyStore and KeyStorePassword properties. |
KeyStore |
(Optional) Used for server RSA authentication. Specifies the location of the keystore (.jks file). Set this property if you specify UseServerRSA. |
KeyStorePassword |
(Optional) Specify the keystore password. This is used for server RSA authentication. Set this property if you specify UseServerRSA. |
| UseUserPassword | (Optional) If set to true, User and Password authentication (for example, Kerberos) is used to connect to the Server. If you specify this, provide values for User and Password. |
| SyncBaseStreams | (Optional) Asks Event Stream Processor for SYNC_BASE_STREAMS. When set to true, the publisher.commit() method is called after each batch is published to the Event Stream Processor. Default value is true. |
| CommitLimit | (Optional) Max size of batch to process in one call. Default value is 100. |
| User | (Required) The initial connection between SpPersistentSubscribeSource and the Event Stream Processor requires authentication. Enter a valid user name known to the Event Stream Processor. |
| Passwd | (Required) The initial connection between SpPersistentSubscribeSource and the Event Stream Processor requires authentication. Enter a valid password for the user name. |
| Stream++ | (Optional) Name of stream to subscribe to. |
| <Stream++>.TruncateStream | (Required) Stream responsible for truncating data. |
| <Stream++>.OpcodeColumn | (Required) Name for the column where the opcode value is stored. |
| <Stream++>.SequenceColumn | (Required) Name for the column where the sequence number is stored. |
| QueueCapacity | (Optional) SpPersistentSubscribeSource queues the records made available by the Event Stream Processor. The queued records are consumed by a separate thread. This property sets the capacity of the internal queue. When the queue is full, the adapter waits for space to become available. The default value is 4096. If the IsEncrypted property is set to true, the user and password information is passed to the Event Stream Processor before the SSL connection is set up. These details are passed in plain text. |