Start Process Using WEB API and get the Response with the Updated Variables

RE: Start Process Using WEB API and get the Response with the Updated Variables

siddharthb0005 — Mon, 20 Nov 2023 08:40:08 GMT

Using activity chaining in process and on success field of start process function, you can do this there will be no problem in future.

RE: Start Process Using WEB API and get the Response with the Updated Variables

Stefan Helzle — Sun, 19 Nov 2023 10:51:17 GMT

Not.

You need chaining to delay the response up to the point where you gathered the necessary data.

RE: Start Process Using WEB API and get the Response with the Updated Variables

tarunt0003 — Sun, 19 Nov 2023 05:12:39 GMT

Just curious, how can we return the response of process instance without activity chaining the model.

Any suggestions?

RE: Start Process Using WEB API and get the Response with the Updated Variables

rajeshr501 — Wed, 23 Oct 2019 13:45:51 GMT

Hi Alok, So if we want to respond the caller with a synchronous response of inserted PK's and additional response from various other inserts , what can be the best approach ? Suggestion on how you overcome the issue is highly appreciated.

Thanks in advance

Raj

RE: Start Process Using WEB API and get the Response with the Updated Variables

harshav420 — Thu, 17 May 2018 08:28:39 GMT

Sure Alok,
We will work accordingly.

RE: Start Process Using WEB API and get the Response with the Updated Variables

aloks0189 — Thu, 17 May 2018 01:39:00 GMT

Hi harshav420 sometime even when you are not performing any complex logic, this might fail due to load on server. Because when we make asynchronous call means we are asking Appian to trigger this process, whenever applicable (based on the resource availability).

So i suggest, do not rely on this, else you will end up with unexpected result/behavior/bugs at any point of time, and you can't even raise a support ticket, because as per the documentation it's the expected behavior, and i have seen several cases where this approach failed even when we perform very light operation.

RE: Start Process Using WEB API and get the Response with the Updated Variables

harshav420 — Wed, 16 May 2018 08:36:54 GMT

Thanks Alok,

but what we are actually trying to do is .... we are having 2 script tasks and 2 WDSEs where based on some data validations we get the result pv get updated, and based on pv value we are showing the error message. We are not having a very big process in that....does it still fail or do we need to think of any other approach.

RE: Start Process Using WEB API and get the Response with the Updated Variables

aloks0189 — Wed, 16 May 2018 08:26:29 GMT

Hi harshav420 you shouldn't depend upon the activity chaining to get the updated variables values in web API.

Because, a!startProcess() invokes a process asynchronously which means process might start immediately or with some delay based on scheduling algorithm/ based on load on server by considering load balancing.

I know, when you chain the nodes, Appian tries to complete the execution of the chained node as quickly as possible but you cannot rely on that. As per appian documentation, they have clearly mentioned about startProcess function asynchronous behaviour.

Hence, you cannot be sure about these process to start immediately, it's all your assumptions that it will start immediately, and this will drag your application into issues while it's in production.

Also you can capture few details, whether process started successfully or failed using the following attributes of this function: onSuccess, onError

I recommend you, not to rely on this approach, because this will be a temporary solution which won't work always. You need to think about some alternate options to achieve your requirement.

RE: Start Process Using WEB API and get the Response with the Updated Variables

rohitr303 — Wed, 16 May 2018 06:58:40 GMT

RE: Start Process Using WEB API and get the Response with the Updated Variables

harshav420 — Tue, 15 May 2018 16:03:45 GMT

Hi Rohit,

This is working and thanks for the inputs....

RE: Start Process Using WEB API and get the Response with the Updated Variables

harshav420 — Tue, 15 May 2018 08:29:55 GMT

Thanks rob,
let me give a try

RE: Start Process Using WEB API and get the Response with the Updated Variables

harshav420 — Tue, 15 May 2018 08:29:41 GMT

Thanks rohit, let me try that and get back to you.

RE: Start Process Using WEB API and get the Response with the Updated Variables

rohitr303 — Tue, 15 May 2018 07:54:46 GMT

Hello Harsha ,

Sending the updated process variables as the web api response is possible , You just need to activity chain all the nodes in the process model. And in the web api response body return fv!processInfo.pv.variableName.

Hope this helps.

Thanks,
Rohit Ouhal

RE: Start Process Using WEB API and get the Response with the Updated Variables

Robert Shankin — Mon, 14 May 2018 21:50:08 GMT

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