Replicate JSON Services to Multiple Databases via the CData Sync CLI

Always-on applications rely on automatic failover capabilities and real-time access to data. CData Sync for JSON integrates live JSON services into your mirrored databases, always-on cloud databases, and other databases such as your reporting server: Automatically synchronize with remote JSON services from Windows or any machine running Java.

You can use Sync's command-line interface (CLI) to easily control almost all aspects of the replication. You can use the CLI to replicate JSON services to one or many databases without any need to change your configuration.

Connect to JSON Services

You can save connection strings and other settings like email notifications in XML configuration files.

The following example shows how to replicate to SQLite.

Windows

<?xml version="1.0" encoding="UTF-8" ?>
<CDataSync><DatabaseType>SQLite</DatabaseType>
 <DatabaseProvider>System.Data.SQLite</DatabaseProvider>
 <ConnectionString>URI=C:/people.json;DataModel=Relational;</ConnectionString>
 <ReplicateAll>False</ReplicateAll>
 <NotificationUserName></NotificationUserName>
 <DatabaseConnectionString>Data Source=C:\my.db</DatabaseConnectionString>
 <TaskSchedulerStartTime>09:51</TaskSchedulerStartTime>
 <TaskSchedulerInterval>Never</TaskSchedulerInterval>
</CDataSync>

Java

<?xml version="1.0" encoding="UTF-8" ?>
<CDataSync><DatabaseType>SQLite</DatabaseType><DatabaseProvider>org.sqlite.JDBC</DatabaseProvider>
<ConnectionString>URI=C:/people.json;DataModel=Relational;</ConnectionString>
<ReplicateAll>False</ReplicateAll>
<NotificationUserName></NotificationUserName>
<DatabaseConnectionString>Data Source=C:\my.db</DatabaseConnectionString>
</CDataSync>

See the Getting Started chapter in the data provider documentation to authenticate to your data source: The data provider models JSON APIs as bidirectional database tables and JSON files as read-only views (local files, files stored on popular cloud services, and FTP servers). The major authentication schemes are supported, including HTTP Basic, Digest, NTLM, OAuth, and FTP. See the Getting Started chapter in the data provider documentation for authentication guides.

After setting the and providing any authentication values, set to more closely match the data representation to the structure of your data.

The property is the controlling property over how your data is represented into tables and toggles the following basic configurations.

• Document (default): Model a top-level, document view of your JSON data. The data provider returns nested elements as aggregates of data.
• FlattenedDocuments: Implicitly join nested documents and their parents into a single table.
• Relational: Return individual, related tables from hierarchical data. The tables contain a primary key and a foreign key that links to the parent document.

See the Modeling JSON Data chapter for more information on configuring the relational representation. You will also find the sample data used in the following examples. The data includes entries for people, the cars they own, and various maintenance services performed on those cars.

Configure Replication Queries

Sync enables you to control replication with standard SQL. The REPLICATE statement is a high-level command that caches and maintains a table in your database. You can define any SELECT query supported by the JSON API. The statement below caches and incrementally updates a table of JSON services:

REPLICATE people;

You can specify a file containing the replication queries. This enables you to use the same replication queries to replicate to several databases.

Run Sync

After you have configured the connection strings and replication queries, you can run Sync with the following command-line options:

Windows

JSONSync.exe -g MySQLiteConfig.xml -f JSONSync.sql

Java

java -Xbootclasspath/p:c:\sqlitejdbc.jar -jar JSONSync.jar -g MySQLiteConfig.xml -f JSONSync.sql