Workflow Definition Id vs. Key

[meyerdan]

AT:

• it is less confusing than in Camunda 7

[meyerdan]

@berndruecker says:

bitte nicht wie heute - topp 1 Fehler der Leute.
Die ID sollte die ID aus dem bpmn XML sein. Der name ID sollte immer das XML >referenzieren.
Für die konkrete Version/bisherigen primär Schlüssel: das muss irgendwie anders heißen. Hmm -spontane Gedanken:
Uuid
UniqueId
Braucht man das überhaupt in der public API? Ist nicht ID + Version in der Kombi eindeutig? Dann konnte man doch auch das nehmen?
Ich denk nochmal drüber nach. Aber ID sollte auf jeden Fall dem im XML entsprechen

[meyerdan]

I gave this some thought: what about calling it what it is: bpmnProcessId ?

Could be something like

client.workflows().start()
    .byBpmnProcessId("foo")
    .execute();

and the WorkflowDefinition would have a method .getBpmnProcessId()

[berndruecker]

Spontane Gedanken:

• UUID
• UniqueId
• CamundaId
• VersionedId

[menski]

• id -> Database Id
• processId -> XML Id

[berndruecker]

Noooooooo!!!!!!!!!!!!!!!!!!!!!!!! Please no "id" for anything else than the BPMN XML id.

[berndruecker]

For me it is ok to have bpmnProcessId
But how is the primary key named? That is still open

[meyerdan]

Just for context:
A related topic is the id vs. key discussion to refer to the identity of an object.
Since we are completely log structured / event oriented we will always have multiple events relating to state transitions of the same "object". For example, there are many events relating to a single "Activity Instance".

I am leaning towards calling that identity "key". All events relating to the same thing have the same key but may have an individual unique ids if required (but probably that is just their log position).

The term key is what is used by event systems like Kafka to relate to this identity. It is also what is used by databases "primary key" and key value stores.

Note: the "key" also needs to be known at lower layers like the log for concepts like "key compaction" (there it is :) ) to work…

Applied to this topic this would mean:

• WorkflowDefinition.getKey() => returns a generated identity key of type long
• WorkflowDefinition.getBpmnProcessId() => returns a String corresponding to the value of the id attribute in Bpmn XML.

I like this proposal my only insecurity is whether it would completely confuse Camunda 7 users :)

[berndruecker]

WorkflowDefinition.getObjectIdentityKey()?

[berndruecker]

Yeah - getKey() is really confusing for C7 Users

[ThorbenLindhauer]

I haven't got a good idea, but I think it should be something short because the name is going to be pretty much in every API method we are going to build.

For example client.tasks().complete().objectIdentityKey(123L).execute() is not so sexy.

[meyerdan]

I case I haven't said it already: Naming sucks.

[berndruecker]

Maybe name it "objectKey" everywhere? Not too long to be annoying, but clear what it means?

So:

• WorkflowDefinition.getObjectKey() => returns a generated identity key of type long
• WorkflowDefinition.getBpmnProcessId() => returns a String corresponding to the value of the id attribute in Bpmn XML.