WebSocket

The WebSocket connector is very similar to the Stream Simulator connector, except that rather than looping through a file, it would either connect through web sockets, long polling, or repeatedly poll an external URL for new records to process.

Using WebSocket

1. Launch the Connect to Data dialog and then select WebSocket.

The WebSocket Connection dialog displays.

 

2. Provide the following information:

1. • URL

The URL to which the WebSocket server will respond to.

1. • User ID

The User ID that will be used to connect to the WebSocket server.

1. • Password

The password that will be used to connect to the WebSocket server.

You can opt to check the Show Characters box to display the password characters.

1. • Request Body

For both the HTTP and ws:// POST requests sent to the WebSocket server.

1. • Timeout in Seconds (to wait for Server response)

NOTE: The URL, User ID, Password, and the Request Body can be parameterized, to allow dynamical data retrieval.

3. Enter the Record Path.

4. Select any of the following Message Types:

1. • JSON

   • Text

The dialog slightly changes to allow specification of the following:

 

3. 1. • Text Qualifier

This drop-down list box specifies if fields are enclosed by text qualifiers, and if present to ignore any column delimiters within these text qualifiers.

3. 1. • Column Delimiter

This drop-down list box specifies the column delimiter to be used when parsing the text file.

3. 1. • First Row Headings

This checkbox determines if the first row should specify the retrieved column heading, and not to be used in data discovery.

1. • XML

5. Select the Decimal Separator. This specifies the character for decimal separation, when parsing a numeric value. By default this is “.”

6. The schema of the source file is then defined by clicking the Generate Columns… button.

This populates the list of columns, with the data type found from inspecting the first ‘n’ rows of the file.

7. Click Add Column.

8. Enter or select:

9. • Name

   • XPath/JsonPath/Text Column Index (for example, price/@stock)

   • Type (Numeric, Text or Date/Time)

   • Date/Time format when the Data Type is Time

1. NOTE:

2. To parse and format times with higher than millisecond precision, the format string needs to end with a period followed by sequence of lower case Fs. There can be no additional characters following them.

3. For example: yyyy-MM-dd HH:mm:ss.ffffff

10.  

    • Enabled (determines whether the message field should be processed)

    • Filter (defined parameters that can be used as Filter)

JSON

Text

XML

You can also opt to click to delete a column in the list.

9. You can opt to save the columns definition into an XML format by clicking the Save button. The saved XML files are placed in …\Public\Public Documents\Datawatch Desktop\Column Schemas.

10. Click Load to load the column schema.

11. Expand Real-Time Settings.

Refer to Defining Real-Time Settings for more information.

12. Click OK to confirm the selection and retrieve the record set into Panopticon Designer (Desktop).

Initially, there is no data displayed in the Data Source Preview section of the Edit Data Table window.

Click the Start Preview button to display the data and refresh the values depending on the defined Refresh Period.