How to – Use Custom API to create custom messages in Dynamics 365
Custom API (preview) allows us to define our custom messages that can be called from web services, similar to Custom Actions. Usually, we would be creating custom workflow actions just to create a new message, to which we can hook our plugin, without defining any logic in the workflow. For this scenario or pattern now we can use Custom API instead.
There are different ways of creating a custom API.
Through the Maker Portal.
Using Web API or Organization Service.
Editing the solution files.
The 3 key entities involved here are
CustomAPI
CustomAPIRequestParameter
CustomAPIResponseProperty
Let us try creating a CustomAPI through the maker portal.
Create a new solution, and click on New and select Custom API
Let us start with a very basic custom action.
Unique Name
This will be the name of the message. Should have the prefix same as solution’s publisher.
Name
The name of the Custom API will show up inside the solution
Display Name
Localized display name of the Custom API
Description
Localized description of the Custom API
Binding Type
Value: 0 Label: Global
Value: 1 Label: Entity
Value: 2 Label: EntityCollection
Bound Entity Logical Name
Logical name of the entity in case of binding type – Entity and EntityCollection.
Is Function
Value: 0 Label: No
Value: 1 Label: Yes
Allowed Custom Processing Step Type
Value: 0 Label: None Meaning: No custom processing steps allowed.
Value: 1 Label: Async Only Meaning: Only asynchronous custom processing steps allowed
Value: 2 Label: Sync and Async Meaning: No restriction. 3rd party plug-ins can add synchronous logic to change the behavior of the message
Execute Privilege Name
Name of the Privilege that is required for the execution of the Custom API.
Plugin Type
Reference of the plugin registered for the Custom API
So right now we have a very basic custom API registered of Global type, which doesn’t allow any steps to be registered and doesn’t need any privileges to execute
Let us write a sample plugin and associate with this new message.
Let us register the assembly
Now let us go back to our Custom API record and associate the Plugin registered.
Let us trigger the plugin by calling the Custom API through the Postman.
Let us check the plugin trace log inside Dynamics 365 App.
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