Recently, we faced an interesting import failure while moving a solution containing a Custom API.
Solution “Temp Plugin Step Custom API Transfer” failed to import: Lookup value 8f3269b7-a24d-43e4-9319-0c5e7ddf2b53 is not resolvable.
This clearly pointed to a lookup resolution issue — the solution import process was trying to bind the Custom API to a Plugin Type (class), but couldn’t find the referenced plugin in the target environment.
Each Custom API will have its own folder inside the Solution.
Looking into the solution files (specifically the customapi.xml) of that particular Custom API, we found this section:
Notice the <plugintypeexportkey> tag. This is where the Custom API references the Plugin Type (the actual C# class implementing the logic).
When a Plugin class is created in Dynamics 365, it gets assigned a unique Plugin Type Id (GUID).
In the source environment, the Custom API was tied to a plugin with ID 420c7261-7461-4b37-87f0-1afcec427a46. However, in the destination environment, which was another development environment, a different plugin class was already created for that custom api. So during solution import, Dataverse tried to match the GUID 420c7261… but couldn’t find it in the target environment. Hence, the lookup resolution failed, and the solution import was blocked.
To resolve this, we manually updated the GUID in the customapi.xml to match the Plugin Type Id of the destination environment. Below, we are getting the ID from the Plugin Registration tool. The other option to fix would have been to remove the Plugin reference from the source, export, and then import.
After making this change, we re-imported the solution, and it worked successfully.
We can define the Custom API’s binding type as Global, Entity, or Entity Collection. In this post, we can see how a Global and Entity binding type Custom API can be defined, write a corresponding plugin, and then invoke/test through Postman.
We can create Custom API through Plugin Registration Tool, Power Apps, Code, Solution files, and or can use XrmToolBox Plugin – Custom API Manager.
Below we have defined a Custom API name custom_GlobalAPI, with binding type as Global and one Request (input) parameter and Response (output) Property of type string.
Below is how we define the plugin type for it and can access the input and output parameters through context.
To test it we can use the XrmToolBox Custom API Tester plugin as shown below
And from Postman, once we have the access token, we can call the Custom API as shown below.
Now for a Bound Custom API, we have the following definition. It is bound to the Contact table and has one input parameter and one output parameter similar to our Global Custom API.
Below is how we define the plugin type for it, and can access the input and output parameters similar to Global Custom API.
However, in the case of binding type Entity, we will have the Request parameter named Target of type Entity Reference for the bound entity added automatically.
We can test it using the Custom API Tester plugin, however as it is bound type, we need to select/specify the contact record (the table it is bound to), before we can execute it.
To call it from Postman, we need to use the fully qualified name i.e. Microsoft.Dynamics.CRM.[unique name of the Custom API] unlike Global one.
public class APIPluginGlobal : IPlugin
{
public void Execute(IServiceProvider serviceProvider)
{
ITracingService tracingService = (ITracingService)serviceProvider.GetService(typeof(ITracingService));
IPluginExecutionContext context = (IPluginExecutionContext)serviceProvider.GetService(typeof(IPluginExecutionContext));
IOrganizationServiceFactory factory = (IOrganizationServiceFactory)serviceProvider.GetService(typeof(IOrganizationServiceFactory));
IOrganizationService orgService = factory.CreateOrganizationService(context.UserId);
try
{
tracingService.Trace("start plugin execution: {0}", this.GetType().FullName);
// check for the message name i.e. Unique Name of the Custom API
if (context.MessageName.Equals("custom_GlobalAPI", StringComparison.OrdinalIgnoreCase))
{
// check for the request parameter in the inputparamters of the context
if (context.InputParameters.Contains("inputParam"))
{
// get the value of the input parameter
string inputValue = context.InputParameters["inputParam"].ToString();
// set the value of response property through outputparameters
context.OutputParameters["outputParam"] = "Got following value as Input : " + inputValue;
}
}
tracingService.Trace("end plugin execution: {0}", this.GetType().FullName);
}
catch (System.ServiceModel.FaultException<OrganizationServiceFault> ex)
{
tracingService.Trace(ex.Detail.Message);
throw;
}
catch (Exception ex)
{
tracingService.Trace(ex.ToString());
throw;
}
}
}
public class APIPluginBound : IPlugin
{
public void Execute(IServiceProvider serviceProvider)
{
ITracingService tracingService = (ITracingService)serviceProvider.GetService(typeof(ITracingService));
IPluginExecutionContext context = (IPluginExecutionContext)serviceProvider.GetService(typeof(IPluginExecutionContext));
IOrganizationServiceFactory factory = (IOrganizationServiceFactory)serviceProvider.GetService(typeof(IOrganizationServiceFactory));
IOrganizationService orgService = factory.CreateOrganizationService(context.UserId);
try
{
tracingService.Trace("start plugin execution: {0}", this.GetType().FullName);
// unique name of the custom api
if (context.MessageName.Equals("custom_BoundAPI", StringComparison.OrdinalIgnoreCase))
{
// Target property of type Entity Reference
if (context.InputParameters.Contains("Target") &&
context.InputParameters["Target"] is EntityReference)
{
var contact = (EntityReference)context.InputParameters["Target"];
// access the input request parameter
if (context.InputParameters.Contains("inputParam"))
{
string inputValue = context.InputParameters["inputParam"].ToString();
// set the output parameter value
context.OutputParameters["outputParam"] = "Got following as Input Parameter : " + inputValue
+ " for record : " + contact.Id.ToString();
}
}
}
tracingService.Trace("end plugin execution: {0}", this.GetType().FullName);
}
catch (System.ServiceModel.FaultException<OrganizationServiceFault> ex)
{
tracingService.Trace(ex.Detail.Message);
throw;
}
catch (Exception ex)
{
tracingService.Trace(ex.ToString());
throw;
}
}
}
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