Importing Schemas from other module doesn't work.

My setup: -typescript server and typescript client as 2 different projects, importing a common third project that contains shared/common stuff, especially the data model and the Schema, and exposes them as es6 modules

Even with a simple Schema such as:

export class TestSchema extends Schema {
    @type("number")
    whatever = 2;
}

When a client joins the server, i get the error on the client:

JOIN ERROR { Error: SchemaSerializer error. See: https://docs.colyseus.io/migrating/0.10/#new-default-serializer
    at new MatchMakeError (/home/stefano/project-x/project-x-webclient/node_modules/colyseus.js/lib/Client.js:58:28)
    at Client.<anonymous> (/home/stefano/project-x/project-x-webclient/node_modules/colyseus.js/lib/Client.js:182:35)
    at step (/home/stefano/project-x/project-x-webclient/node_modules/colyseus.js/lib/Client.js:45:23)
    at Object.next (/home/stefano/project-x/project-x-webclient/node_modules/colyseus.js/lib/Client.js:26:53)
    at fulfilled (/home/stefano/project-x/project-x-webclient/node_modules/colyseus.js/lib/Client.js:17:58)
    at <anonymous>
    at process._tickDomainCallback (internal/process/next_tick.js:228:7) code: 4213 }

and on the server:

Error: SchemaSerializer error. See: https://docs.colyseus.io/migrating/0.10/#new-default-serializer
    at SchemaSerializer.reset (/home/stefano/project-x/project-x-server/node_modules/colyseus/lib/serializer/SchemaSerializer.js:13:19)
    at GameRoom.setState (/home/stefano/project-x/project-x-server/node_modules/colyseus/lib/Room.js:108:26)
    at GameRoom.onCreate (/home/stefano/project-x/project-x-server/src/GameRoom.ts:12:14)
    at /home/stefano/project-x/project-x-server/node_modules/colyseus/lib/MatchMaker.js:214:28
    at Generator.next (<anonymous>)
    at /home/stefano/project-x/project-x-server/node_modules/colyseus/lib/MatchMaker.js:7:71
    at new Promise (<anonymous>)
    at __awaiter (/home/stefano/project-x/project-x-server/node_modules/colyseus/lib/MatchMaker.js:3:12)
    at createRoom (/home/stefano/project-x/project-x-server/node_modules/colyseus/lib/MatchMaker.js:200:12)
    at Object.<anonymous> (/home/stefano/project-x/project-x-server/node_modules/colyseus/lib/MatchMaker.js:44:30)

If the TestSchema class is defined in the server project, no error is encountered, it only triggers when I import it from the common project. The error fails on a instanceof check, I guess because the server and the common project have 2 different versions of the Schema class and therefore that check fails.

[MastroLindus]

New version fixed it. I guess that using some js bundlers it should be possible to detect if the same module with the same version gets imported twice and ensure that only one copy is bundled, and that also should fix this issue. However the newer code also works, thanks!, Feel free to close the issue or keep it around until 0.12.x is stable!

[Zielak]

MastroLindus is right. I stumbled upon the same issue last week while I was messing about with npm link. In my case, my whole “base” project is a monorepo (Lerna managed), so both client and server side are in one dir, using the same “shared” node_modules. Then i have seperate project for the actual game, which is importing the “base” client and server libs. Maybe that could be your temporary solution?