Expression Script Examples

Expression language can be used to write scripts in QPR ProcessAnalyzer. See how expression scripts can be created in the Workspace. For documentation for the syntax, functions and entities can be found from the main page in the KPI Expression Language section.

Examples

Call Web Service

Contact to a web service, fetch some data, and store it to a datatable.

let datatableName = "Web Service Data";
let webServiceData = ParseJson(ReadWebService(
    #{"Address": "https://processanalyzer.onqpr.com/qprpa/api/serverinfo"}
));

let targetDatatable = Project.Datatables.Where(name==datatableName);
if (Count(targetDatatable) == 0) {
	targetDatatable = Project.CreateDatatable(datatableName)
	.AddColumn("Setting name", "String")
	.AddColumn("Setting value", "String")
	.AddColumn("Data read", "DateTime");
} else {
	targetDatatable = targetDatatable[0];
}

let currentTime = Now;
let dataAsDf = ToDataFrame(
	webServiceData.keys.{
        let key = _;
        [key, webServiceData[key], currentTime];
    },
	["Setting name", "Setting value", "Data read"]
);
targetDatatable.Import(dataAsDf, #{"Append":true});
WriteLog(`${CountTop(dataAsDf.Rows)} rows written to datatable`);

Store Data to Datatable

Get all models in the system and store them to a datatable.

let newDatatable = Project
    .CreateDatatable("Models list " + ToString(Now, "dd.MM.yyyy HH:mm:ss"))
    .AddColumn("Model name", "String")
    .AddColumn("Project name", "String")
    .AddColumn("Created time", "DateTime")
    .AddColumn("Cases", "Integer");
let startTime = Now;
let modelsData = ToDataFrame(
    Models.([Name, Project.Name, CreatedDate, NCases]),
    ["Model name", "Project name", "Created time", "Cases"]
);
WriteLog(`Listing models took ${(Now - startTime).TotalSeconds.Round(2)} seconds.`);
newDatatable.Import(modelsData);
WriteLog(`Datatable ${newDatatable.Id} created.`);

Convert Datatable Column Data

This script can be used to convert a single column into numerical data type. To use the script, you need to setup the following in the beginning of the script:

• Project name where the datatable is located.
• Datatable name
• Name of the column to be converted

Note that the conversion fails, if there is data that cannot be converted into numerical format. The conversion assumes that period (.) is used as the decimal point.

let projectName = "New Project";
let datatableName = "qpr processanalyzer events";
let columnName = "Event order in case";

let project = (Projects.Where(Name==projectName))[0];
let datatable = (project.Datatables.Where(Name==datatableName))[0];
DatatableById(datatable.Id).DataFrame
.SetColumns([
	columnName: () => {
		let data = Column(columnName);
		if (data == null) {
			null;
		 } else {
			ToFloat(data);
		}
	}
])
.Persist(datatable.Name, ["ProjectId": project.Id, "Append": false]);

Instead of converting to numeric (with the ToFloat function), data can be converted into string using the ToString function.

Show DataFrame as HTML Table

This script defines a function to show dataframe as a HTML table, and uses the function for a literal dataframe.

function dataframeToHtmlTable(df) {
	return
`<table>
	<tr>
		${StringJoin("\r\n\t\t",  + df.columns.`<th>${_}</th>`)}
	</tr>
	${StringJoin("", df.Rows.(
		"\r\n\t<tr>" + StringJoin("", _.`\r\n\t\t<td>${ToString(_)}</td>`) + "\r\n\t</tr>"
	))}
</table>`
}

let data = ToDataFrame(
	[
		["one", "two", "three"],
		["four", "five", "six"],
		["seven", "eight", "nine"]
	],
	["Column 1", "Column 2", "Column 3"]
);

return dataframeToHtmlTable(data);