Concurrent kore-rpc server

[goodlyrottenapple]

Implements the proposal from runtimeverification/hs-backend-booster#383

Namely:

add-module

• now returns the id of a given module, of the form m<sha256_of_given_module>
• computes the SHA256 hash of the unparsed module string and saves the internalised module under this key
• takes an optional name-as-id: true argument which implements the previous behaviour of add-module (still returns the new id), i.e. adds the module to the module map under the module name as well as the id.
• if the same module is added twice with name-as-id: true, the second request will fail with a Duplicate module error
• if the same module is sent twice with name-as-id: false or without name-as-id, the second request is idempotent and will succeed

As discussed on the issue, the IDs and original names are not disjoint for ease of implementation. the m pre-pended to the hash is necessary to make the name a valid kore identifier.

I have also not added the modules field to other methods as I'm unsure whether this should be replacing the current module parameter, which would be a backwards incompatible change to the API that would break a lot of our integration tests, or if it should be an additional field, @tothtamas28?

[tothtamas28]

if the same module is added twice with name-as-id: true, the second request will fail with a Duplicate module error

I think the Duplicate module error is only necessary if the modules are not the same (but the names are). Otherwise, the request can be idempotent.

I have also not added the modules field to other methods

Does this mean that the modules are still added globally, but now the unique ID's work for module imports? If so, that's reasonable, we can tackle the breaking changes in the new year.

[goodlyrottenapple]

I think the Duplicate module error is only necessary if the modules are not the same (but the names are). Otherwise, the request can be idempotent.

Ok, will make that change

Does this mean that the modules are still added globally, but now the unique ID's work for module imports? If so, that's reasonable, we can tackle the breaking changes in the new year.

Yes all modules are added globally and you can send in a module that imports other modules via their ID.