Open

You create and edit streams in the Stream editor, which you open by clicking Create new stream or opening an existing stream on the Solution page. It consists of a canvas, a function library, a toolbar, execution buttons, and status and validation indicators.

Open

Stream editor, with canvas, Function library and toolbar

In the the Stream editor, you have two modes; View and Edit. When creating a new stream, the Stream editor will open up in Edit mode and when opening an existing stream, the Stream editor will open up in View mode and the function library will not be visible. You can switch between the two modes by using the the View and Edit buttons in the toolbar.

To return to the Solution page, click on the arrow to the left of the stream name.

Function library

The function library contains all the integrated functions you can use in Usage Engine sorted into three tabs based on the function type; Collectors, Processors, and Forwarders.

For information on the different functions in the function library, see Functions. 

Toolbar

The toolbar contains the following buttons and settings:

Button/Setting	Description

Button/Setting	Description
Open	View button - When the button is blue, you are in View mode. When the button is white, you are in Edit mode. Click on this button to switch to View mode.
Open	Edit button - When the button is blue, you are in Edit mode. When the button is white, you are in View mode. Click on this button to switch to Edit mode. Note! If you navigate away from the Stream editor, you will switch to View mode. The Edit mode will only be active as long as you keep the Stream editor open.
Open	Export button - Click on this button to open the Export stream dialog, in which you can either copy the content of the stream, or exported the stream to import into a solution. See Solutions for more information.
Open	View audit button - Click on this button to open the Audit page for the stream. See Audit for more information.
Open	View logs button - Click on this button to open the Logs page for the stream. See Logs for more information.
Open	Undo button - Click on this button to undo your latest change to the stream.
Open	Redo button - Click on this button to redo the latest change you undid using the Undo button.
Open	Zoom slider - Use the zoom slider to zoom the canvas in and out.

Execution buttons

The following execution buttons are available

Button	Description

Button	Description
Open	Start button - When you have created a complete stream with no errors, click on the Start button to run it. The status will then turn into Running and the Start button will turn into the Stop button. When the stream has completed the run, the button will turn into the Start button again. Hint! You can also start a stream in the Solution page by clicking on the More button for the stream and selecting Start from the popup menu, see Solutions.
Open	Stop button - You can stop a running stream at any time by clicking on the Stop button. The status will then turn into Stopped and the Stop button will turn into the Start button. Hint! You can also stop a stream in the Solution page by clicking on the More button for the stream and selecting Stop from the popup menu, see Solutions.

Status and validation indicators

The stream can have the following status and validations:

Status/Validation

Status/Validation
-	The stream has never been run or is pending a run.
Open	Running - The stream is running
Open	Complete - The stream run has ended successfully
Open	Failed - The stream run was terminated due to a problem.
Open	Stopped - The stream run has been stopped.
Open	The stream configuration is valid.
Open	The stream configuration is not valid and has 5 issues. The validation will fail in any of the cases listed in Stream editor Stream editor | Validation. Click on the red dot with the number of issues to display a list with descriptions of the different issues. Click on Configuration in the list to open the Function editor for the function with an error where you can fix the issue. It will then be removed from the error list. You cannot start a stream run until you have corrected all of the errors listed.

Validation rules

A Stream is considered invalid if:

• it does not have a collector

• it does not begin with a collector

• it does not contain a processor

• it contains a processor with one or more unlinked outputs.

• it does not end with a forwarder

• it contains routes from functions that are going back to functions located earlier in the stream

• there are multiple streams in a single stream configuration (multiple collectors connected to different processors and different forwarders)

Building a stream

Build your stream by adding the functions needed to process your data according to your requirements and linking them together to define the data flow in your stream. Each stream must include a collector, processor and a forwarder function.

You add functions by dragging them from the function library and dropping them onto the canvas. Double click on the function, or right-click the function and click on the Edit button, to open the Function editor where you can configure the function. When functions have been configured, you can add links between their connection points.

See My First Stream for more information on creating streams.

Keyboard shortcuts

When you have configured functions in one or more streams, you may want to re-use or move them and you can do this by using the available keyboard shortcuts.

Click on a function to select it and SHIFT-click to select several functions. The functions do not need to be adjacent when selecting multiple.

You can now use any of the following shortcuts: