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1	1	{{container}}{{container layoutStyle="columns"}}(((
2		-In a low-code platform like eMagiz, you want to prevent using custom scripting as much as possible. However, sometimes in practice, you encounter situations that cannot be realized with the standard toolbox provided within the platform. As a result, we offer the option to use a Groovy script in these situations to achieve the desired solution. In this microlearning, we will look at where you can use a Groovy script and discuss the key considerations when implementing a Groovy script within your model.
	2	+When your integration landscape grows through time, you might decide to split functional business processes into multiple eMagiz models. In those cases, the question of connecting these models easily, stable, and securely could arise. This microlearning will focus on that question and provide an answer based on our vision and best practices when dealing with the platform.
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4	4	Should you have any questions, please get in touch with [[academy@emagiz.com>>mailto:academy@emagiz.com]].
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10	10	== 2. Key concepts ==
11	11
12		-This microlearning focuses on groovy scripts. A groovy script is a piece of code written in the groovy language that allows you to extend the platform's functionality beyond the mere use of the components supplied via the flow designer.
	12	+This microlearning focuses on communication between two eMagiz models. When communicating to any external party (from the view of a certain model) you should always consider the following:
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14		-* Groovy scripts should be viewed as an extension that can be used in fringe cases, not as a standard best practice
15		-* When a groovy script becomes so complex that you are programming, you should consider alternatives to the solution
16		-* Groovy scripts can be used in a filter, transformation, and as part of a standard executor
17		-* Groovy scripts should be well documented as they are though to read for most of our community members
18		-* There is no guarantee from eMagiz that Groovy scripts within models keep working in newer versions of the platform
	14	+* Security
	15	+* Loose coupling
	16	+* Maintainability
	17	+* Clarity
19	19
20		-== 3. Groovy script ==
	19	+== 3. Communication between models ==
21	21
22	22	In a low-code platform like eMagiz, you want to prevent using custom scripting as much as possible. However, sometimes in practice, you encounter situations that cannot be realized with the standard toolbox provided within the platform. As a result, we offer the option to use a Groovy script in these situations to achieve the desired solution. In this microlearning, we will look at where you can use a Groovy script and discuss the key considerations when implementing a Groovy script within your model.
23	23
24		-=== 3.1 Implementation in Create ===
	23	+Most users would think that communication via queues to connect two separate eMagiz models is a smart idea. However, this is something that we do not encourage. We discourage this for several practical and technical reasons alike.
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26		-To implement a groovy script in Create, you first need to consider what your Groovy script should do. Then, within the flow designer, there are five components available that can handle a Groovy script.
27		-
28		-* In case you want the Groovy script to filter out messages, you should implement the Groovy script in a "standard filter" component.
29		-* If you want your Groovy script to always transform your message from a certain format into another format, you should consider using a "standard transformer" component.
30		-* The "standard service activator" is your friend if you need an optional output. So, for example, when you want to do some transformation and check whether a message can continue, you can use the "standard service activator" and have an optional output.
31		-* When you want to split your message based on a Groovy script, you should use the "standard splitter."
32		-* If you want to route messages based on a Groovy script, you should use the "standard router."
	25	+When looking at the practical side of things getting it configured correctly is time-consuming and an error-prone action (as is evident by the question). Furthermore, it can lead to unexpected situations in which you make a typo to listen to a queue on which no messages are provided. This queue will however be registered on the JMS level (when you activate the flow in question with the custom configuration) which can lead to confusing queue statistics and even more troublesome false-positive alerting based on missing queue metrics or missing consumers.
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34		-{{warning}}Note that in practice, we mainly see use cases for the "standard service activator" and the "standard transformation." {{/warning}}
	27	+On top of that because you basically allow one model to write and read from queues registered in another model maintaining both models will become very confusing for the ones working on the project at the moment but also for those working on it at a later stage and does that need to provide (incidental) support on the environments.
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36		-[[image:Main.Images.Microlearning.WebHome@expert-data-handling-groovy-script-available-components.png]]
	29	+Another practical reason for not wanting this is that we do not actively support this use case from eMagiz. This means that when we do updates to our technical infrastructure we will not take this scenario into account. This could lead to additional work on your part in the future and reduced stability of your solution.
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38		-Regardless of the component you choose, you always need to select the "Groovy script" option and reference the Groovy resource available on the flow level you want to use within the component.
	31	+From the technical point of view, the consequence of this construction is that both models need to know each other certificates and credentials which are not considered secure. On top of that because you, theoretically, can exchange data from any queue to any queue you could create a situation in which updates in one model trigger changes in the other model (i.e. when using the same data model) that are unexpected (and frankly unwanted).
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40		-[[image:Main.Images.Microlearning.WebHome@expert-data-handling-groovy-script-groovy-configuration.png]]
	33	+We advise using functionality that makes it explicit that both models function independently of each other. From eMagiz we consider two valid alternatives for this:
	34	+- Using a web service as a layer of communication between the two models. This web service can be REST or SOAP and has been implemented before
	35	+- Using the Event Streaming functionality of eMagiz to write and read from topics.
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42		-{{info}}As you can see in the help text when selecting the "resource" attribute, you need to make sure that the Groovy script is uploaded within the context of your flow.{{/info}}
	37	+Both alternatives have the benefit that the security can be tight and explicit (i.e. only model A can write/post data to model B). Furthermore managing the solution becomes a lot easier as it makes use of the standard functionality within the platform. We have no plans to support this approach in the product.
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44		-After you have the component in such a way that the correct Groovy script is called, you are done with the component's configuration and can test the flow using flow testing.
45		-
46		-=== 3.2 Key considerations ===
47		-
48		-* To make some groovy scripts work, you need to upload (third-party) Java libraries that are not packaged on default by eMagiz
49		-* To make some groovy scripts work, you need to reference Java libraries via a standard header enricher or as a dummy variable
50		-* The store consists of several groovy scripts that might be of use to you
51		-* Groovy scripts should be viewed as an extension that can be used in fringe cases, not as a standard best practice
52		-* When a groovy script becomes so complex that you are programming, you should consider alternatives to the solution
53		-* Groovy scripts can be used in a filter, transformation, and as part of a standard executor
54		-* Groovy scripts should be well documented as they are though to read for most of our community members
55		-* There is no guarantee from eMagiz that Groovy scripts within models keep working in newer versions of the platform
56		-
57	57	== 4. Assignment ==
58	58
59		-Try to implement a component that references a Groovy script and see whether the flow can be tested.
	41	+Consider what your criteria are when communicate between models and compare them to our criteria.
60	60	This assignment can be completed with the help of the (Academy) project you created/used in the previous assignment.
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62	62	== 5. Key takeaways ==
63	63
64		-* To make some groovy scripts work, you need to upload (third-party) Java libraries that are not packaged on default by eMagiz
65		-* To make some groovy scripts work, you need to reference Java libraries via a standard header enricher or as a dummy variable
66		-* The store consists of several groovy scripts that might be of use to you
67		-* Groovy scripts should be viewed as an extension that can be used in fringe cases, not as a standard best practice
68		-* When a groovy script becomes so complex that you are programming, you should consider alternatives to the solution
69		-* Groovy scripts can be used in a filter, transformation, and as part of a standard executor
70		-* Groovy scripts should be well documented as they are though to read for most of our community members
71		-* There is no guarantee from eMagiz that Groovy scripts within models keep working in newer versions of the platform
	46	+* Consider the following when communication between two models
	47	+** Security
	48	+** Loose coupling
	49	+** Maintainability
	50	+** Clarity
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73	73	== 6. Suggested Additional Readings ==
74	74
75		-If you are interested in this topic and want more information, please read the help text provided by eMagiz and read the following link:
76		-* https://www.tutorialspoint.com/groovy/index.htm
	54	+If you are interested in this topic and want more information, please consult us at [[productmanagement@emagiz.com>>mailto:productmanagement@emagiz.com]]
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78	78	== 7. Silent demonstration video ==
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