Inbound web service that can both create and update incidents?

[peterraeves]

We are creating an Inbound Web Service that can do 3 things. Create, update and close an Incident. What would best practice be here? Should I create 3 services? Should I create a single Service with 3 transform maps? Should I create a single service with a single TM that covers all situations?

I thought about all situations but all of them had bad points to them. So I thought I'd turn to you guys who are much smarter than me.

1. 3 Services & 3 Transform Maps

+: Easier for the external customer, as the name of the service is clear and they will receive only a single result

-: Double work for field maps/values that are the same for all services

2. 1 Service & 3 Transform Maps

+: Single interface, so customer does not need to worry about what to call

+: Only need maps for those fields that are needed for the current service

-: The external customer will receive the results of 3 TMs

-: All TMs need onBefore maps to check whether they should run

-: Double work for field maps/values that are the same for all services

3. 1 Service & 1 Transform Map

+: Everything is centralized

-: Cannot use coalesce field 'number', because it will not be present when creating a new ticket. This will cause the TM to fail.

PS: As a bonus question, where should I put default values. For example, for the contact_type field, I'd like to enter 'Automated Event', which is not the overal default. Where would I put this assignment? Field Map? Transform Script?

[Chuck Tomasi]

For this level of complexity, I recommend a scripted (SOAP) web service or a scripted REST API. It gives you control over what parameters you pass and what actions the API takes, including what response you get back.

Scripted REST APIs

http://wiki.servicenow.com/index.php?title=Scripted_Web_Services

[peterraeves]

It's not really that complex though. The biggest issue I'm dealing with is really something simple. I would like to use number as coalesce field, but do not want to tell the customer to enter the field empty to create a message, because that's just ugly. I expected ServiceNow to handle the missing coalesce variable as it being a new record

[Mike Allen]

I used 1 table with coalescence on the sys_id.   That way, the only thing anyone ever calls is insert.   It goes into a staging table and the single transform map picks up from there.   If there is no reference sys_id given, it inserts.   If there is a reference sys_id, it updates the parent record.   If the state is close, it updates the record and closes it.

Your response on the initial insert will give you the sys_id of the record created.   Just capture that and pass it with each subsequent call to do updates.

[Mike Allen]

As an answer to your bonus question, I put these in the Field Map.   Just map it from script and make the answer equal your value.