Fail to try Deno Demo example

[YievCkim]

Steps to reproduce

I am discovering feathers as I try to find a web framework for deno. I know bout feathers here: https://deno.land/x/[email protected]

sadly the demo code given on deno.land doesn't build. I have made some obvious fix but running this script till fails with an error in feathers.

This is my program:

// app.ts
import { feathers } from 'https://deno.land/x/[email protected]/mod.ts';

type Message = {
  message: string;
}

class MyService {
  async create (data: Message) {
    return data;
  }
}

type ServiceTypes = {
  myservice: MyService
}

const app = feathers<ServiceTypes>();

app.use('myservice', new MyService());

app.service('myservice').on('created', (data: Message) => {
  console.log('Created', data);
});

await app.service('myservice').create({
  message: 'Hello from Deno'
});

And this is the errors I got with:

% deno run --allow-net test.ts
Download https://deno.land/x/[email protected]/mod.ts
Download https://deno.land/x/[email protected]/_feathers/mod.ts
Download https://deno.land/x/[email protected]/_feathers/service.ts
Download https://deno.land/x/[email protected]/_feathers/hooks/index.ts
Download https://deno.land/x/[email protected]/_feathers/dependencies.ts
Download https://deno.land/x/[email protected]/_feathers/version.ts
Download https://deno.land/x/[email protected]/_feathers/declarations.ts
Download https://deno.land/x/[email protected]/_feathers/application.ts
Download https://deno.land/x/[email protected]/_events/events.js
Download https://deno.land/x/[email protected]/_commons/mod.ts
Download https://deno.land/x/[email protected]/_feathers/events.ts
Download https://deno.land/x/[email protected]/_feathers/hooks/legacy.ts
Download https://deno.land/x/[email protected]/_commons/debug.ts
Check file:///Users/mickaelviey/Dev/troll-tracker/test.ts
error: TS2532 [ERROR]: Object is possibly 'undefined'.
    typeof service[m] === 'function' && !methods.includes(m)
                                         ~~~~~~~
    at https://deno.land/x/[email protected]/_feathers/service.ts:30:42

TS2769 [ERROR]: No overload matches this call.
  Overload 1 of 2, '(...items: ConcatArray<string>[]): string[]', gave the following error.
    Argument of type 'string[] | undefined' is not assignable to parameter of type 'ConcatArray<string>'.
      Type 'undefined' is not assignable to type 'ConcatArray<string>'.  Overload 2 of 2, '(...items: (string | ConcatArray<string>)[]): string[]', gave the following error.
    Argument of type 'string[] | undefined' is not assignable to parameter of type 'string | ConcatArray<string>'.
      Type 'undefined' is not assignable to type 'string | ConcatArray<string>'.
  ).concat(methods);
           ~~~~~~~
    at https://deno.land/x/[email protected]/_feathers/service.ts:31:12



TS2769 [ERROR]: No overload matches this call.
  Overload 1 of 2, '(o: {}): string[]', gave the following error.
    Argument of type 'string[] | undefined' is not assignable to parameter of type '{}'.
      Type 'undefined' is not assignable to type '{}'.  Overload 2 of 2, '(o: object): string[]', gave the following error.
    Argument of type 'string[] | undefined' is not assignable to parameter of type 'object'.
      Type 'undefined' is not assignable to type 'object'.
  if (Object.keys(serviceOptions.methods).length === 0 && typeof service.setup !== 'function') {
                  ~~~~~~~~~~~~~~~~~~~~~~
    at https://deno.land/x/[email protected]/_feathers/service.ts:72:19



TS2532 [ERROR]: Object is possibly 'undefined'.
    if (typeof context.event === 'string' && !events.includes(context.event)) {
                                              ~~~~~~
    at https://deno.land/x/[email protected]/_feathers/events.ts:16:47

TS2532 [ERROR]: Object is possibly 'undefined'.
    const appHooks = app.appHooks[HOOKS].concat(app.appHooks[this.method] || []);
                     ~~~~~~~~~~~~~~~~~~~
    at https://deno.land/x/[email protected]/_feathers/hooks/index.ts:38:22

TS2531 [ERROR]: Object is possibly 'null'.
    this._middleware.push(...mw);
    ~~~~~~~~~~~~~~~~
    at https://deno.land/x/[email protected]/_feathers/hooks/index.ts:55:5

TS2322 [ERROR]: Type '<A>(this: A, service: FeathersService<A, Service<any, Partial<any>>>, path: string, options: ServiceOptions) => FeathersService<...>' is not assignable to type 'ServiceMixin<Application<ServiceTypes, AppSettings>>'.
  Types of parameters 'options' and 'options' are incompatible.
    Type 'ServiceOptions | undefined' is not assignable to type 'ServiceOptions'.
      Type 'undefined' is not assignable to type 'ServiceOptions'.
  mixins: ServiceMixin<Application<ServiceTypes, AppSettings>>[] = [ hookMixin, eventMixin ];
                                                                     ~~~~~~~~~
    at https://deno.land/x/[email protected]/_feathers/application.ts:29:70

TS2345 [ERROR]: Argument of type 'ServiceOptions | undefined' is not assignable to parameter of type 'ServiceOptions'.
  Type 'undefined' is not assignable to type 'ServiceOptions'.
    const protoService = wrapService(location, service, options);
                                                        ~~~~~~~
    at https://deno.land/x/[email protected]/_feathers/application.ts:97:57

TS2532 [ERROR]: Object is possibly 'undefined'.
      this.appHooks[HOOKS].push(...hookMap as any);
      ~~~~~~~~~~~~~~~~~~~~
    at https://deno.land/x/[email protected]/_feathers/application.ts:124:7

TS2769 [ERROR]: No overload matches this call.
  Overload 1 of 2, '(...items: ConcatArray<HookFunction<Application<ServiceTypes, AppSettings>, any>>[]): HookFunction<Application<ServiceTypes, AppSettings>, any>[]', gave the following error.
    Argument of type 'HookFunction<Application<ServiceTypes, AppSettings>, any>[] | undefined' is not assignable to parameter of type 'ConcatArray<HookFunction<Application<ServiceTypes, AppSettings>, any>>'.
      Type 'undefined' is not assignable to type 'ConcatArray<HookFunction<Application<ServiceTypes, AppSettings>, any>>'.  Overload 2 of 2, '(...items: (HookFunction<Application<ServiceTypes, AppSettings>, any> | ConcatArray<HookFunction<Application<ServiceTypes, AppSettings>, any>>)[]): HookFunction<...>[]', gave the following error.
    Argument of type 'HookFunction<Application<ServiceTypes, AppSettings>, any>[] | undefined' is not assignable to parameter of type 'HookFunction<Application<ServiceTypes, AppSettings>, any> | ConcatArray<HookFunction<Application<ServiceTypes, AppSettings>, any>>'.
      Type 'undefined' is not assignable to type 'HookFunction<Application<ServiceTypes, AppSettings>, any> | ConcatArray<HookFunction<Application<ServiceTypes, AppSettings>, any>>'.
        this.appHooks[key] = methodHooks.concat(methodHookMap[key]);
                                                ~~~~~~~~~~~~~~~~~~
    at https://deno.land/x/[email protected]/_feathers/application.ts:131:49



Found 10 errors.

System configuration

Module versions (especially the part that's not working):

deno.land/x/[email protected]/mod.ts

Deno version:

% deno --version      
deno 1.14.3 (release, x86_64-apple-darwin)
v8 9.4.146.16
typescript 4.4.2

Operating System:
MacOSX 11 (Big Sur)

[despiegk]

same problem here

[IuryPiva]

Just a typescript warning, I got it working by running the flag --no-check which skip type checking modules.
e.g. deno run --allow-net main.ts --no-check

[FossPrime]

The demo is a little bit outdated... I know beta 14 changed a substantial amount of types. Ideally the generator could generate Deno code... TS 4.5 with Node ESM mode is remarkcably close to how deno handles this... aside from the .ts/.js extension swap. But as it becomes mandatory with the combination of esModulesInterop: false, package.json/type: module and ts-node/type: module, it should be "easy" to implement.

Try doing a find and replace on the v5.0.0-pre.10 part of the version numbers to the latest.

[marshallswain]

Update in this area: We are working on a complete port of Feathers core to Deno. Only the packages that have hard node dependencies, like Express, Koa, etc, will not be ported. Everything that gets moved to Deno will be published to both platforms. We have a bunch of contributions to merge before this, so it will take a while.

[daffl]

The main issue for Deno support is #1964, we'll track progress there.

[SamuelQZQ]

Add this into you deno.json file can fix the problem.

{
    "compilerOptions": {
        "strictNullChecks": false,
        "noImplicitAny": false
    }
}