Difference between CDM and CDM messages

To conclude our section on microlearnings that all have something to do with the CDM we wrap things up by learning what the difference is between CDM and CDM messages.

Should you have any questions, please contact academy@emagiz.com.

1. Prerequisites

• Basic knowledge of the eMagiz platform

2. Key concepts

This microlearning centers around understanding the difference between CDM and CDM messages.
By CDM we mean: The Canonical Data Model that plays a vital and central role while exchanging data between various systems via the messaging pattern

• The complete CDM consists of the collection of entities that are used or going to be used in the various CDM messages

3. Difference between CDM and CDM messages

Simply put the difference between the CDM and the CDM messages is as follows:

• The CDM holds all entities and attributes that are relevant within the context of your complete integration landscape.
• The CDM message is tailor-made for a specific piece of data (i.e. Order, Invoice, Employee) and only holds the entities and attributes relevant for that piece of data.

When a new system message needs to be processed, new entities have to be created. These entities have to be generic, according to the language and notation of the CDM. Thus, the entities have to be created in the CDM first. After that, these entities can be created in a CDM message, gateway message, or topic message. Once the entities and attributes have been created in a CDM message, gateway message, or topic message, they can be mapped to the entities and attributes from the system message.
 
Note that both the CDM and CDM/gateway/topic message show all entities and attributes that are relevant within the context of your complete integration landscape. The main difference is that the CDM message only holds the entities and attributes that are tailor-made for a specific piece of data. This is indicated in green.
 
Below, the CDM for a model is shown.

An example of a CDM message for this model is the following:

  
This CDM message holds the entities CrashCourse and Design, as indicated in green.
Once the entities and attributes have been created, the message definitions have to be added. As explained before, a system message is specific to the system, whereas a CDM/gateway/topic message is generic and consistent across systems. For the system message, it is possible to add complete entities, but it is also possible to add only one attribute to the system message definition. This can be done by using the Toggle canvas edit mode button, hovering over the desired attribute and clicking on it. The attributes can also be removed individually. 

  
For a CDM/gateway/topic message it also possible to add and remove entities and attributes. This can be done by hovering over the desired entities or attributes and clicking on them. The Toggle canvas edit mode button is not present here, it is only needed to hover over the entities/attributes. A minus will appear when the entity/attribute is already present in the message definition. By clicking, the entity/attribute will then be removed from the message definition. In case a plus appears, the entity/attribute is not yet present in the message definition, and can be added by clicking on it. 

4. Key takeaways

• The CDM holds all entities and attributes that are relevant within the context of your complete integration landscape.
• The CDM message is tailor-made for a specific piece of data (i.e. Order, Invoice, Employee) and only holds the entities and attributes relevant for that piece of data.

5. Suggested Additional Readings

If you are interested in this topic and want more information on it please read the help text provided by eMagiz when executing these actions.