openhab-docs/configuration/blockly/rules-blockly-run-and-process.md

---
layout: documentation
title: Rules Blockly - Run & Process and Transformations
---
<!-- markdownlint-disable MD036 -->

# Run & Process (Rules and Scripts)

[return to Blockly Reference](index.html#run-process-rules-and-scripts)

## Introduction

This section contains several possibilities

- Calling Rules or other scripts either located as files on the server or provided via the UI
- Retrieving attributes provided by the rule context or from the own caller rule.
- Transforming values via different conversion methods (map, regex, jsonpath)

**A note about Rules and Scripts**

A Script _is_ a Rule too. It’s just a special type of rule that only has a single script action and a “Script” tag.

[[toc]]

## Overview of the Run & Process blocks

![run-and-process-blocks](../images/blockly/blockly-run-and-process.png)

## Run & Process Blocks

See also the short video part about ![youtube](../images/blockly/youtube-logo-small.png) [Run & Process blocks, transform](https://youtu.be/KwhYKy1_qVk?t=2110)

### Call Script File

![run-script-file](../images/blockly/blockly-run-script.png)

_Function:_ Calls a script file with the given name which must be located in the _$OPENHAB_CONF/scripts/_ folder.

- No parameters can be provided

See [openHAB Call-Script](https://www.openhab.org/docs/configuration/actions.html#openhab-subsystem-actions) for background information

### Run Rule or Script created in UI

![run-rule-or-script](../images/blockly/blockly-run-rule.png)

_Function:_ calls another _rule_ or _script_ that was created via the openHAB UI.

The  _ruleUID_ can be found in the list of rules or scripts in the second line of the list (like here _helloBlockly_ or _helloWorld_)
![rule-uuid](../images/blockly/blockly-run-rule-uuid.png)

Parameters are optional:

- If not providing parameters leave the _with context_ section as is.
- If providing parameters you **must** replace the _create empty dictionary_ block with [the _dictionary_ block from the Lists section](https://community.openhab.org/t/blockly-reference/128785#lists-76), modifying the number of key/value pairs to suit.

Notes:

- parameters can be retrieved in the called script via the "get context attribute"-block (see below)
- the called rule / script cannot return any value
- it is not possible to access a particular function in another script or rule as scripts / rules have to be perceived as completely autonomous
- the called rule / script is run synchronously

### Retrieve context attribute from rule

Function: Retrieve context attributes passed by a calling rule/script (see above)

![retrieve-context](../images/blockly/blockly-retrieve-context.png)

This retrieves the value for the key "myKey1" that was passed by the calling rule.

_Example_

![retrieve-context-example](../images/blockly/blockly-retrieve-context-example.png)

### Retrieve rule context information

![retrieve-context-info](../images/blockly/blockly-retrieve-rule-context-info.png)

_Function:_ Retrieve event context related information of the rule

A rule carries contextual information when triggered - this block can retrieve that information.

- The rule trigger type defines which of the attributes are available to the rule - the types available depend on the trigger type of the rule.
- For more detailed information see [UI Event Object](https://next.openhab.org/addons/automation/jsscripting/#ui-event-object) or [openHAB Events](https://www.openhab.org/docs/developer/utils/events.html).

Here is a list of possible values that can be retrieved.

- rule UID - String
- event type - String
- new state of item - String / Number by selection
- previous state of item - String / Number by selection
- triggering item name - [Item](rules-blockly-items-things.html#item), not a String
- received command - String / Number by selection
- triggered channel - String
- triggered event - String

The block adds a selection drop down in case a state or command is returned:

![blockly-context-number-string](../images/blockly/blockly-context-number-string.gif)

## Transform values via Map, Regex or JsonPath and others

openHAB provides many [transformations](https://www.openhab.org/docs/configuration/transformations.html):

- [Map](https://www.openhab.org/addons/transformations/map/)
- [Regex](https://www.openhab.org/addons/transformations/regex/)
- [JsonPath](https://www.openhab.org/addons/transformations/jsonpath/)
- [Binary to Json](https://www.openhab.org/addons/transformations/bin2json/)
- [Exec](https://www.openhab.org/addons/transformations/exec/)
- [Jinja](https://www.openhab.org/addons/transformations/jinja/)
- [Scale](https://www.openhab.org/addons/transformations/scale/)
- [XPath](https://www.openhab.org/addons/transformations/xpath/)
- [XSLT](https://www.openhab.org/addons/transformations/xslt/)

The following describes examples for Map, Regex, and JsonPath

![map](../images/blockly/blockly-transform-map.png)
![regex](../images/blockly/blockly-transform-regex.png)
![jsonpath](../images/blockly/blockly-transform-jsonpath.png)

Function: Transform the given value via one of the different transformation methods

### Example 1: Regex

Convert  #123456 into rgb(12,34,56)

![transform-regex](../images/blockly/blockly-transform-example1.png)

### Example 2: JsonPath transformation

Extract the temperature from the following JSON

```json
{ "device": { "location": "Outside", "status": { "temperature": 23.2 }}}
```

by using the jsonpath

```json
$.device.status.temperature
```

![transform-jsonpath](../images/blockly/blockly-transform-example2.png)

### Example 3: Map transformation

This example applies a map transformation from the map file nanoleaf.map in _$OPENHAB-CONF/transform/_

![transform-map](../images/blockly/blockly-transform-example3.png)

The above, with the below map file

```text
ON=Ja
OFF=Nein
effects=Effekte
-=?
NULL=n/a
hs = Hue/Saturation
ct = Color Temperature
```

would result in the following log entry

```bash
Hue/Saturation
```

## Inline Script

![inline-script](../images/blockly/blockly-inline-script.png)

_Function:_ execute arbitrary ECMAScript content

Provides the possibility to inject any ECMAScript at a given position.
This should be used in cases when Blockly does not provide the desired functionality.
Use with diligence.

### Example

![inline-script-example](../images/blockly/blockly-inline-script-example.png)

See also the short video part about ![youtube](../images/blockly/youtube-logo-small.png) [Inline Scripts](https://youtu.be/KwhYKy1_qVk?t=2165)

## Return to Blockly Reference

[return to Blockly Reference](index.html#run-process-rules-and-scripts)