RSS Connection Details¶

Introduction¶

Connector Version

This documentation is based on version 23.0.8936 of the connector.

Get Started¶

RSS Version Support

The connector surfaces RSS 2.0 feeds as relational tables, enabling standards-based access to the real-time data streaming capabilities of RSS.

Establish a Connection¶

The RSS connector supports connecting to RSS and Atom feeds, as well as feeds with custom extensions. To connect to a feed, set the URI property. The connector also supports accessing secure feeds. A variety of authentication mechanisms are supported. See the connection properties for details.

Create a Schema¶

You can use the GenerateSchemaFiles property to generate table definitions for RSS and ATOM feeds. This property can be used to generate schemas when you connect or when you execute a query. Set the URI to the feed URL and the Format is the format of the feed RSS or ATOM. Set the Location connection property to the folder where you want the resulting schemas to be placed.

Alternatively, you can call the CreateSchema stored procedure.

EXEC CreateSchema TableName='MyFeed', URL='http://myservice/myfeed/'

The schema is written in RSBScript, a simple configuration language that allows you to define the columns for the table. You are able to make modifications by adding, removing, or editing columns.

Add a Column¶

Table columns are defined in the rsb:info block, which defines the column names, data types, element path. To add a new column to a table, you can simply append an attribute to rsb:info. You will need to set the following values:

• name: the desired column name. The column names do not need to match the element names from the feed; you will define this mapping in the next step.
• xs:type: an appropriate data type. The connector accepts the following data types: int, double, datetime, time, string, long, boolean, and decimal.
• key: whether this column is a primary key (a unique identifier that can be used to select this record and this record only).
• other:xPath: path to the element relative to the channel

Remove a Column¶

Deleting an attr element from rsb:info will remove the column from the resource. This means that your table will not list the column. Note that it is important to delete the entire XML element for the column that you want to remove.

Edit a Column¶

You can rename a column by changing the name attribute of the attr. You can also edit a column's data type by changing the xs:type attribute to one of the following support types:

• string
• datetime
• boolean
• int
• long
• double

Important Notes¶

Configuration Files and Their Paths¶

• All references to adding configuration files and their paths refer to files and locations on the Harmony Agent where the connector is installed. These paths are to be adjusted as appropriate depending on the agent and the operating system. If multiple agents are used in an agent group, identical files will be required on each agent.

Advanced Features¶

This section details a selection of advanced features of the RSS connector.

User Defined Views

The connector allows you to define virtual tables, called user defined views, whose contents are decided by a pre-configured query. These views are useful when you cannot directly control queries being issued to the drivers. See User Defined Views for an overview of creating and configuring custom views.

SSL Configuration

Use SSL Configuration to adjust how connector handles TLS/SSL certificate negotiations. You can choose from various certificate formats; see the SSLServerCert property under "Connection String Options" for more information.

Proxy

To configure the connector using Private Agent proxy settings, select the Use Proxy Settings checkbox on the connection configuration screen.

Query Processing

The connector offloads as much of the SELECT statement processing as possible to RSS and then processes the rest of the query in memory (client-side).

See Query Processing for more information.

User Defined Views¶

The RSS connector allows you to define a virtual table whose contents are decided by a pre-configured query. These are called User Defined Views, which are useful in situations where you cannot directly control the query being issued to the driver, e.g. when using the driver from Jitterbit. The User Defined Views can be used to define predicates that are always applied. If you specify additional predicates in the query to the view, they are combined with the query already defined as part of the view.

There are two ways to create user defined views:

• Create a JSON-formatted configuration file defining the views you want.
• DDL statements.

Define Views Using a Configuration File¶

User Defined Views are defined in a JSON-formatted configuration file called UserDefinedViews.json. The connector automatically detects the views specified in this file.

You can also have multiple view definitions and control them using the UserDefinedViews connection property. When you use this property, only the specified views are seen by the connector.

This User Defined View configuration file is formatted as follows:

• Each root element defines the name of a view.
• Each root element contains a child element, called query, which contains the custom SQL query for the view.

For example:

{
    "MyView": {
        "query": "SELECT * FROM RSSFeed WHERE MyColumn = 'value'"
    },
    "MyView2": {
        "query": "SELECT * FROM MyTable WHERE Id IN (1,2,3)"
    }
}

Use the UserDefinedViews connection property to specify the location of your JSON configuration file. For example:

"UserDefinedViews", "C:\Users\yourusername\Desktop\tmp\UserDefinedViews.json"

Define Views Using DDL Statements¶

The connector is also capable of creating and altering the schema via DDL Statements such as CREATE LOCAL VIEW, ALTER LOCAL VIEW, and DROP LOCAL VIEW.

Create a View¶

To create a new view using DDL statements, provide the view name and query as follows:

CREATE LOCAL VIEW [MyViewName] AS SELECT * FROM Customers LIMIT 20;

If no JSON file exists, the above code creates one. The view is then created in the JSON configuration file and is now discoverable. The JSON file location is specified by the UserDefinedViews connection property.

Alter a View¶

To alter an existing view, provide the name of an existing view alongside the new query you would like to use instead:

ALTER LOCAL VIEW [MyViewName] AS SELECT * FROM Customers WHERE TimeModified > '3/1/2020';

The view is then updated in the JSON configuration file.

Drop a View¶

To drop an existing view, provide the name of an existing schema alongside the new query you would like to use instead.

DROP LOCAL VIEW [MyViewName]

This removes the view from the JSON configuration file. It can no longer be queried.

Schema for User Defined Views¶

User Defined Views are exposed in the UserViews schema by default. This is done to avoid the view's name clashing with an actual entity in the data model. You can change the name of the schema used for UserViews by setting the UserViewsSchemaName property.

Work with User Defined Views¶

For example, a SQL statement with a User Defined View called UserViews.RCustomers only lists customers in Raleigh:

SELECT * FROM Customers WHERE City = 'Raleigh';

An example of a query to the driver:

SELECT * FROM UserViews.RCustomers WHERE Status = 'Active';

Resulting in the effective query to the source:

SELECT * FROM Customers WHERE City = 'Raleigh' AND Status = 'Active';

That is a very simple example of a query to a User Defined View that is effectively a combination of the view query and the view definition. It is possible to compose these queries in much more complex patterns. All SQL operations are allowed in both queries and are combined when appropriate.

SSL Configuration¶

Customize the SSL Configuration¶

By default, the connector attempts to negotiate SSL/TLS by checking the server's certificate against the system's trusted certificate store.

To specify another certificate, see the SSLServerCert property for the available formats to do so.

Data Model¶

Views

The RSS connector models RSS entities in relational Views, or read-only tables. The connector dynamically obtains the schemas; reconnect to pick up any changes such as column names or data types.

Customizing the Dynamic Schemas

You can create custom schemas by either using the GenerateSchemaFiles connection property or calling the CreateSchema stored procedure.

Stored Procedures¶

Stored procedures are function-like interfaces that extend the functionality of the connector beyond simple SELECT operations with RSS.

Stored procedures accept a list of parameters, perform their intended function, and then return any relevant response data from RSS, along with an indication of whether the procedure succeeded or failed.

RSS Connector Stored Procedures¶

CreateSchema¶

Creates a schema file for the collection.

CreateSchema¶

Creates a local schema file (.rsd) from an existing table or view in the data model.

The schema file is created in the directory set in the Location connection property when this procedure is executed. You can edit the file to include or exclude columns, rename columns, or adjust column datatypes.

The connector checks the Location to determine if the names of any .rsd files match a table or view in the data model. If there is a duplicate, the schema file will take precedence over the default instance of this table in the data model. If a schema file is present in Location that does not match an existing table or view, a new table or view entry is added to the data model of the connector.

Input¶

Result Set Columns¶

System Tables¶

You can query the system tables described in this section to access schema information, information on data source functionality, and batch operation statistics.

Schema Tables¶

The following tables return database metadata for RSS:

• sys_catalogs: Lists the available databases.
• sys_schemas: Lists the available schemas.
• sys_tables: Lists the available tables and views.
• sys_tablecolumns: Describes the columns of the available tables and views.
• sys_procedures: Describes the available stored procedures.
• sys_procedureparameters: Describes stored procedure parameters.
• sys_keycolumns: Describes the primary and foreign keys.
• sys_indexes: Describes the available indexes.

Data Source Tables¶

The following tables return information about how to connect to and query the data source:

• sys_connection_props: Returns information on the available connection properties.
• sys_sqlinfo: Describes the SELECT queries that the connector can offload to the data source.

Query Information Tables¶

The following table returns query statistics for data modification queries:

• sys_identity: Returns information about batch operations or single updates.

sys_catalogs¶

Lists the available databases.

The following query retrieves all databases determined by the connection string:

SELECT * FROM sys_catalogs

Columns¶

sys_schemas¶

Lists the available schemas.

The following query retrieves all available schemas:

SELECT * FROM sys_schemas

Columns¶

sys_tables¶

Lists the available tables.

The following query retrieves the available tables and views:

SELECT * FROM sys_tables

Columns¶

sys_tablecolumns¶

Describes the columns of the available tables and views.

The following query returns the columns and data types for the RSSFeed table:

SELECT ColumnName, DataTypeName FROM sys_tablecolumns WHERE TableName='RSSFeed'

Columns¶

sys_procedures¶

Lists the available stored procedures.

The following query retrieves the available stored procedures:

SELECT * FROM sys_procedures

Columns¶

sys_procedureparameters¶

Describes stored procedure parameters.

The following query returns information about all of the input parameters for the SearchFeed stored procedure:

SELECT * FROM sys_procedureparameters WHERE ProcedureName='SearchFeed' AND Direction=1 OR Direction=2

Columns¶

sys_keycolumns¶

Describes the primary and foreign keys.

The following query retrieves the primary key for the RSSFeed table:

SELECT * FROM sys_keycolumns WHERE IsKey='True' AND TableName='RSSFeed'

Columns¶

sys_foreignkeys¶

Describes the foreign keys.

The following query retrieves all foreign keys which refer to other tables:

SELECT * FROM sys_foreignkeys WHERE ForeignKeyType = 'FOREIGNKEY_TYPE_IMPORT'

Columns¶

sys_primarykeys¶

Describes the primary keys.

The following query retrieves the primary keys from all tables and views:

SELECT * FROM sys_primarykeys

Columns¶

sys_indexes¶

Describes the available indexes. By filtering on indexes, you can write more selective queries with faster query response times.

The following query retrieves all indexes that are not primary keys:

SELECT * FROM sys_indexes WHERE IsPrimary='false'

Columns¶

sys_connection_props¶

Returns information on the available connection properties and those set in the connection string.

When querying this table, the config connection string should be used:

jdbc:cdata:rss:config:

This connection string enables you to query this table without a valid connection.

The following query retrieves all connection properties that have been set in the connection string or set through a default value:

SELECT * FROM sys_connection_props WHERE Value <> ''

Columns¶

sys_sqlinfo¶

Describes the SELECT query processing that the connector can offload to the data source.

Discovering the Data Source's SELECT Capabilities¶

Below is an example data set of SQL capabilities. Some aspects of SELECT functionality are returned in a comma-separated list if supported; otherwise, the column contains NO.

The following query retrieves the operators that can be used in the WHERE clause:

SELECT * FROM sys_sqlinfo WHERE Name = 'SUPPORTED_OPERATORS'

Note that individual tables may have different limitations or requirements on the WHERE clause; refer to the Data Model section for more information.

Columns¶

sys_identity¶

Returns information about attempted modifications.

The following query retrieves the Ids of the modified rows in a batch operation:

SELECT * FROM sys_identity

Columns¶

sys_information¶

Describes the available system information.

The following query retrieves all columns:

SELECT * FROM sys_information

Columns¶

Advanced Configurations Properties¶

The advanced configurations properties are the various options that can be used to establish a connection. This section provides a complete list of the options you can configure. Click the links for further details.

Authentication

Feed

SSL

Schema

Miscellaneous

Authentication¶

This section provides a complete list of authentication properties you can configure.

AuthScheme¶

The scheme used for HTTP authentication. Accepted entries are NTLM, Basic, Digest, Negotiate and None.

Possible Values¶

None, Basic, Digest, NTLM, Negotiate

Data Type¶

string

Default Value¶

None

Remarks¶

The scheme used for HTTP authentication. Accepted entries are NTLM, Basic, Digest, Negotiate and None. None is the default option.

• NTLM: Set this to use your Windows credentials for authentication.
• Basic: Set this to use HTTP Basic authentication.
• Digest: Set this to use HTTP Digest authentication.
• Negotiate: If AuthScheme is set to Negotiate, the connector will negotiate an authentication mechanism with the server. Set AuthScheme to Negotiate if you want to use Kerberos authentication.

AuthToken¶

The token used for authentication.

Data Type¶

string

Default Value¶

""

Remarks¶

An authtoken is a unique secret identifier that can be used to identify the validity of an HTTP request. Several applications and servers use this mechanism to secure feeds. The authtoken set in the connection will be posted with the HTTP server as the request variable '@authtoken'.

URI¶

The URI (Uniform Resource Identifier) of the feed.

Data Type¶

string

Default Value¶

""

Remarks¶

This property specifies a URI for the RSS Feed resource location. This can be an http source or file.

Feed¶

This section provides a complete list of the Feed properties you can configure.

Format¶

The Format property specifies whether the data is in RSS or ATOM.

Possible Values¶

RSS, ATOM

Data Type¶

string

Default Value¶

RSS

Remarks¶

This property can be used with the CreateSchema stored procedure or the Generate Schema File feature (Set GenerateSchemFiles to OnStart or OnUse)

SSL¶

This section provides a complete list of SSL properties you can configure.

SSLServerCert¶

The certificate to be accepted from the server when connecting using TLS/SSL.

Data Type¶

string

Default Value¶

""

Remarks¶

If using a TLS/SSL connection, this property can be used to specify the TLS/SSL certificate to be accepted from the server. Any other certificate that is not trusted by the machine is rejected.

This property can take the following forms:

If not specified, any certificate trusted by the machine is accepted.

Certificates are validated as trusted by the machine based on the System's trust store. The trust store used is the 'javax.net.ssl.trustStore' value specified for the system. If no value is specified for this property, Java's default trust store is used (for example, JAVA_HOME\lib\security\cacerts).

Use '*' to signify to accept all certificates. Note that this is not recommended due to security concerns.

Schema¶

This section provides a complete list of schema properties you can configure.

Location¶

A path to the directory that contains the schema files defining tables, views, and stored procedures.

Data Type¶

string

Default Value¶

%APPDATA%\RSS Data Provider\Schema

Remarks¶

The path to a directory which contains the schema files for the connector (.rsd files for tables and views, .rsb files for stored procedures). The folder location can be a relative path from the location of the executable. The Location property is only needed if you want to customize definitions (for example, change a column name, ignore a column, and so on) or extend the data model with new tables, views, or stored procedures.

If left unspecified, the default location is "%APPDATA%\RSS Data Provider\Schema" with %APPDATA% being set to the user's configuration directory:

BrowsableSchemas¶

This property restricts the schemas reported to a subset of the available schemas. For example, BrowsableSchemas=SchemaA,SchemaB,SchemaC.

Data Type¶

string

Default Value¶

""

Remarks¶

Listing the schemas from databases can be expensive. Providing a list of schemas in the connection string improves the performance.

Tables¶

This property restricts the tables reported to a subset of the available tables. For example, Tables=TableA,TableB,TableC.

Data Type¶

string

Default Value¶

""

Remarks¶

Listing the tables from some databases can be expensive. Providing a list of tables in the connection string improves the performance of the connector.

This property can also be used as an alternative to automatically listing views if you already know which ones you want to work with and there would otherwise be too many to work with.

Specify the tables you want in a comma-separated list. Each table should be a valid SQL identifier with any special characters escaped using square brackets, double-quotes or backticks. For example, Tables=TableA,[TableB/WithSlash],WithCatalog.WithSchema.`TableC With Space`.

Note that when connecting to a data source with multiple schemas or catalogs, you will need to provide the fully qualified name of the table in this property, as in the last example here, to avoid ambiguity between tables that exist in multiple catalogs or schemas.

Views¶

Restricts the views reported to a subset of the available tables. For example, Views=ViewA,ViewB,ViewC.

Data Type¶

string

Default Value¶

""

Remarks¶

Listing the views from some databases can be expensive. Providing a list of views in the connection string improves the performance of the connector.

This property can also be used as an alternative to automatically listing views if you already know which ones you want to work with and there would otherwise be too many to work with.

Specify the views you want in a comma-separated list. Each view should be a valid SQL identifier with any special characters escaped using square brackets, double-quotes or backticks. For example, Views=ViewA,[ViewB/WithSlash],WithCatalog.WithSchema.`ViewC With Space`.

Note that when connecting to a data source with multiple schemas or catalogs, you will need to provide the fully qualified name of the table in this property, as in the last example here, to avoid ambiguity between tables that exist in multiple catalogs or schemas.

Miscellaneous¶

This section provides a complete list of miscellaneous properties you can configure.

GenerateSchemaFiles¶

Indicates the user preference as to when schemas should be generated and saved.

Possible Values¶

Never, OnUse, OnStart, OnCreate

Data Type¶

string

Default Value¶

Never

Remarks¶

This property outputs schemas to .rsd files in the path specified by Location.

Available settings are the following:

• Never: A schema file will never be generated.
• OnUse: A schema file will be generated the first time a table is referenced, provided the schema file for the table does not already exist.
• OnStart: A schema file will be generated at connection time for any tables that do not currently have a schema file.
• OnCreate: A schema file will be generated by when running a CREATE TABLE SQL query.

Note that if you want to regenerate a file, you will first need to delete it.

Generate Schemas with SQL¶

When you set GenerateSchemaFiles to OnUse, the connector generates schemas as you execute SELECT queries. Schemas are generated for each table referenced in the query.

When you set GenerateSchemaFiles to OnCreate, schemas are only generated when a CREATE TABLE query is executed.

Generate Schemas on Connection¶

Another way to use this property is to obtain schemas for every table in your database when you connect. To do so, set GenerateSchemaFiles to OnStart and connect.

MaxRows¶

Limits the number of rows returned when no aggregation or GROUP BY is used in the query. This takes precedence over LIMIT clauses.

Data Type¶

int

Default Value¶

-1

Remarks¶

Limits the number of rows returned when no aggregation or GROUP BY is used in the query. This takes precedence over LIMIT clauses.

Other¶

These hidden properties are used only in specific use cases.

Data Type¶

string

Default Value¶

""

Remarks¶

The properties listed below are available for specific use cases. Normal driver use cases and functionality should not require these properties.

Specify multiple properties in a semicolon-separated list.

Integration and Formatting¶

PseudoColumns¶

This property indicates whether or not to include pseudo columns as columns to the table.

Data Type¶

string

Default Value¶

""

Remarks¶

This setting is particularly helpful in Entity Framework, which does not allow you to set a value for a pseudo column unless it is a table column. The value of this connection setting is of the format "Table1=Column1, Table1=Column2, Table2=Column3". You can use the "*" character to include all tables and all columns; for example, "*=*".

Timeout¶

The value in seconds until the timeout error is thrown, canceling the operation.

Data Type¶

int

Default Value¶

60

Remarks¶

If Timeout = 0, operations do not time out. The operations run until they complete successfully or until they encounter an error condition.

If Timeout expires and the operation is not yet complete, the connector throws an exception.

UserDefinedViews¶

A filepath pointing to the JSON configuration file containing your custom views.

Data Type¶

string

Default Value¶

""

Remarks¶

User Defined Views are defined in a JSON-formatted configuration file called UserDefinedViews.json. The connector automatically detects the views specified in this file.

You can also have multiple view definitions and control them using the UserDefinedViews connection property. When you use this property, only the specified views are seen by the connector.

This User Defined View configuration file is formatted as follows:

• Each root element defines the name of a view.
• Each root element contains a child element, called query, which contains the custom SQL query for the view.

For example:

{
    "MyView": {
        "query": "SELECT * FROM RSSFeed WHERE MyColumn = 'value'"
    },
    "MyView2": {
        "query": "SELECT * FROM MyTable WHERE Id IN (1,2,3)"
    }
}

Use the UserDefinedViews connection property to specify the location of your JSON configuration file. For example:

"UserDefinedViews", C:\Users\yourusername\Desktop\tmp\UserDefinedViews.json

Note that the specified path is not embedded in quotation marks.