Features

Message delivery semantics

• Order: Messages are sent in random order. Messages will be sent in order based on keys in the future. In this case, if multiple records of the same primary key are updated, the updates are sent in the same order as the records are updated.

• Repeatability: Lindorm Streams supports the at-least-once semantics, which may cause message duplication.

Message format

Lindorm Streams sends messages that contain only updated content. Assume that a table has three columns: a, b, and c. If a user updates only the c column, the message contains only the primary key data and the updated data of the c column. In the future, Lindorm Streams will support querying the new values and old values of all the cells in the updated row. The following code shows the message format:

{
  "op" : <opType>             // The type of the operation. Valid values: Put and DeleteFamily.
  "table" : <tableName>       // The name of a table.
  "ts" : <defaultVersion>     // The default version. The default version is used if the data in the column does not contain the ts key.
  "keyOnly":<keyOnly>         // Specifies whether only the primary key data is included.
  "data" : [
    {
      "type" : <type>          // The data type of the column.
      "name" : <name>          // The name of the column.
      "ts" : <version>         // The data version. If this value is not specified, the dts value is used as the version.
      "value" : <value>        // The value. If this value is not specified, the value in the table is null.
  },
  {
      "type" : <type>          // The data type of the column.
      "name" : <name>          // The name of the column.
      "ts" : <version>         // The data version. If this value is not specified, the dts value is used as the version.
      "value" : <value>        // The value. If this value is not specified, the value in the table is null.
  }
  ]
}

• The following table describes the content in the message.

Features available soon