Async Interrupt trigger in Service component

If I have a component that is a form, with code in the Async Interrupt trigger I understand how the code responds to the postmessage instruction. However, if the form is converted to a service, how does the code in the Async Interrupt trigger ever execute? Or is the short answer, it never does - because a service only responds to activate instructions that invoke specific operations and once the operation has completed, the service terminates, and there is no opportunity for it to wait and listen for interrupts.

Trying to get a better feel for how services do and do not work.

If I have a component that is a form, with code in the Async Interrupt trigger I understand how the code responds to the postmessage instruction. However, if the form is converted to a service, how does the code in the Async Interrupt trigger ever execute? Or is the short answer, it never does - because a service only responds to activate instructions that invoke specific operations and once the operation has completed, the service terminates, and there is no opportunity for it to wait and listen for interrupts.

Trying to get a better feel for how services do and do not work.

Hi Harjit,

your description is correct when using a single activate instruction to execute your service, like this:

activate "MYSERVICE".myOperation(myParams)

In this case Uniface runtime based on the code is doing for you:
- instanting your service
- executing your operation
- deleting the service instance

To be able to exchange messages with a service your code should explicitely instanciate your service giving it a lifetime in memory, like this:

newinstance "MYSERVICE", "MYSERVICE"
activate "MYSERVICE".myOperation(myParams)
deleteinstance "MYSERVICE"

If you instanciate your service while starting your application you could postmessage it for the whole application lifetime.

I hope it helps.

Gianni

Hi Harjit,

your description is correct when using a single activate instruction to execute your service, like this:

activate "MYSERVICE".myOperation(myParams)

In this case Uniface runtime based on the code is doing for you:
- instanting your service
- executing your operation
- deleting the service instance

To be able to exchange messages with a service your code should explicitely instanciate your service giving it a lifetime in memory, like this:

newinstance "MYSERVICE", "MYSERVICE"
activate "MYSERVICE".myOperation(myParams)
deleteinstance "MYSERVICE"

If you instanciate your service while starting your application you could postmessage it for the whole application lifetime.

I hope it helps.

Gianni

Hi Harjit,

your description is correct when using a single activate instruction to execute your service, like this:

activate "MYSERVICE".myOperation(myParams)

In this case Uniface runtime based on the code is doing for you:
- instanting your service
- executing your operation
- deleting the service instance

To be able to exchange messages with a service your code should explicitely instanciate your service giving it a lifetime in memory, like this:

newinstance "MYSERVICE", "MYSERVICE"
activate "MYSERVICE".myOperation(myParams)
deleteinstance "MYSERVICE"

If you instanciate your service while starting your application you could postmessage it for the whole application lifetime.

I hope it helps.

Gianni

Hi Harjit,

your description is correct when using a single activate instruction to execute your service, like this:

activate "MYSERVICE".myOperation(myParams)

In this case Uniface runtime based on the code is doing for you:
- instanting your service
- executing your operation
- deleting the service instance

To be able to exchange messages with a service your code should explicitely instanciate your service giving it a lifetime in memory, like this:

newinstance "MYSERVICE", "MYSERVICE"
activate "MYSERVICE".myOperation(myParams)
deleteinstance "MYSERVICE"

If you instanciate your service while starting your application you could postmessage it for the whole application lifetime.

I hope it helps.

Gianni

Hi Harjit,

your description is correct when using a single activate instruction to execute your service, like this:

activate "MYSERVICE".myOperation(myParams)

In this case Uniface runtime based on the code is doing for you:
- instanting your service
- executing your operation
- deleting the service instance

To be able to exchange messages with a service your code should explicitely instanciate your service giving it a lifetime in memory, like this:

newinstance "MYSERVICE", "MYSERVICE"
activate "MYSERVICE".myOperation(myParams)
deleteinstance "MYSERVICE"

If you instanciate your service while starting your application you could postmessage it for the whole application lifetime.

I hope it helps.

Gianni

Hi Harjit,

In our application we have several stand-alone (detached) Uniface services running on an application server. We can communicate with these services using postmessage from the client to the service and vice versa.

To create the service I agree with Gianni, but in my opinion the service instance should never be deleted, if the service instance is deleted it can't be addressed anymore because it's gone.

With kind regards,

John Bergsma

Hi Harjit,

your description is correct when using a single activate instruction to execute your service, like this:

activate "MYSERVICE".myOperation(myParams)

In this case Uniface runtime based on the code is doing for you:
- instanting your service
- executing your operation
- deleting the service instance

To be able to exchange messages with a service your code should explicitely instanciate your service giving it a lifetime in memory, like this:

newinstance "MYSERVICE", "MYSERVICE"
activate "MYSERVICE".myOperation(myParams)
deleteinstance "MYSERVICE"

If you instanciate your service while starting your application you could postmessage it for the whole application lifetime.

I hope it helps.

Gianni