Preconfiguration "HttpRequest - Receiving data in JSON format"

HttpRequest data receiving and processing in JSON format

This preconfiguration can be activated when creating a new object (e.g. by "New object" in the local object menu or after pressing the Insert key after selecting the object) and is included in the group: " / Communication / XML, JSON, CSV, text".

This preconfiguration can be used with the objects: PmaFolder or PmaRoot.

- The preconfiguration is created including the panel (object of the PmaPanel type) is functional also a Web panel.

The preconfiguration creates main PmaFolder containing two subfolders:

Commun - allows communication with defined url address that contains the JSON format data

Test - creates graphic panel for testing url addresses

Commun - PmaFolder

Main object configured as communication driver. The PmaFolder object has the StartReceive method for initialization of the communication. The method has following parameters:

msgId - user identifier of the communication

msgUrl - data source URL address

msgPar - user parameter of the message

oRcv - the resulting data of the communication will be passed to the onReceive method of this object. In this object must be the onReceive method that can process the received data.

These parameters are passed to the Add method of the PmaSequencer object.

The PmaSequencer object is configured in order to have each communication running outside the main working thread of the application PROMOTIC. In the onStep event, there is an ActiveX object "Microsoft.XMLHTTP" that gets the corresponding parameters for synchronous mode communication by the open method. The send method follows and receives or sends the data. The received data can be then processed as needed. The transmission is terminated by the abort method.

Test - PmaFolder

The Test subobject with panel and data can be used for communication testing. The onReceive method provides communication error detection and suggestion of received data processing. In panel method GetMsgList, there are three functional url addresses with identifiers that can be selected in the panel in order to test the communication. In this panel it is also possible to test any other url address entered in the PmgString object Msg Url address:

These configurators can be set before the preconfiguration is created:

The name of created object	Name of the object created in the tree of Pma objects. The maximum Pma object name length is 31 characters. This is a system name, so it must contain only alphanumeric and must not contain any diacritics, empty string, spaces and the first character must not be a number. Default: "JsonHttpReq"