Let's say we have a bookshop and an author entity, to show the author their earnings stat, we want to check if the authenticated user is indeed the author themselves. So we have:
#UseGuards(GqlAuthGuard)
#ResolveField(() => [Eearning], { name: 'earnings' })
async getEarnings(
#Parent() author: Author,
#GqlUser() user: User,
) {
if (user.id !== author.id)
throw new UnauthorizedException(
'Each author can only view their own data',
);
// rest of the function implementation
}
We could query this:
query {
author(id: "2bd79-6d7f-76a332b06b") {
earnings {
sells
}
}
}
Now imagine we want to use a custom Guard instead of that if statement. Something like below:
#Injectable()
export class AutherGuard implements CanActivate {
canActivate(context: ExecutionContext): boolean {
const ctx = GqlExecutionContext.create(context);
// const artistId = ?
}
}
How can I access the id argument given to the author query when AutherGuard is used for the getEarnings handler?
Not sure how documented is that but the parent object can be accessed through the getRoot method:
const gqlContext = GqlExecutionContext.create(context);
const root = gqlContext.getRoot();
const authorId = root.id;
In fact, we have a helper function that we use like this:
export function getArgs(context: ExecutionContext): any {
if (context.getType<GqlContextType>() === "graphql") {
const gqlContext = GqlExecutionContext.create(context);
return { ...gqlContext.getArgs(), $parent: gqlContext.getRoot() };
} else if (context.getType() === "http") {
return context.switchToHttp().getRequest().params;
}
}
...
const args = getArgs(context);
const authorId = _.get(args, "$parent.id");
I need dynamically assign a new route but it for some reason refuses to work.
When I send a request in the Postman it just keeps waiting for a response
The whole picture of what I am doing is the following:
I've got a controller with a decorator on one of its methods
#Controller()
export class Test {
#RESTful({
endpoint: '/product/test',
method: 'post',
})
async testMe() {
return {
type: 'hi'
}
}
}
export function RESTful({ endpoint, method, version }: { endpoint: string, version?: string, method: HTTPMethodTypes }) {
return function (target: any, propertyKey: string, descriptor: PropertyDescriptor): void {
const originalMethod = descriptor.value
Reflect.defineMetadata(propertyKey, {
endpoint,
method,
propertyKey,
version
}, target)
return originalMethod
}
}
export function Controller() {
return function (constructor: any) {
const methods = Object.getOwnPropertyNames(constructor.prototype)
Container.set(constructor)
for (let action of methods) {
const route: RESTfulRoute = Reflect.getMetadata(action, constructor.prototype)
if (route) {
const version: string = route.version ? `/${route.version}` : '/v1'
Container.get(Express).injectRoute((instance: Application) => {
instance[route.method](`/api${version}${route.endpoint}`, async () => {
return await Reflect.getOwnPropertyDescriptor(constructor, route.propertyKey)
// return await constructor.prototype[route.propertyKey](req, res)
})
})
}
}
}
}
Is it possible to dynamically set the route in the way?
I mainly use GraphQL but sometimes I need RESTful API too. So, I want to solve this by that decorator
In order for the response to finish, there must be a res.end() or res.json(...) or similar. But I cannot see that anywhere in your code.
I have this:
LocationController.ts
import {GenericController} from './_genericController';
interface Response {
id : number,
code: string,
name: string,
type: string,
long: number,
lat: number
}
const fields = ['code','name','type','long','lat'];
class LocationController extends GenericController{
tableName:string = 'location';
fields:Array<any> = fields;
}
const locationController = new LocationController();
const get = async (req, res) => {
await locationController._get(req, res);
}
export {get};
GenericController.ts
interface Response {
id : number
}
export class GenericController{
tableName:string = '';
fields:Array<any> = [];
_get = async (req, res) => {
try{
const id = req.body['id'];
const send = async () => {
const resp : Array<Response> = await db(this.tableName).select(this.fields).where('id', id)
if (resp[0] === undefined) {
// some error handling
}
res.status(status.success).json(resp[0]);
}
await send();
}catch (error){
// some error handling
}
}
}
What I want to do is to pass the Response interface from LocationController to the GenericController parent, so that the response is typed accurately depending on how the child class has defined it. Clearly it doesn't work like this since the interface is defined outside of the class so the parent has no idea about the Response interface in the LocationController.ts file.
I've tried passing interface as an argument in the constructor, that doesn't work. So is there a way I can make this happen? I feel like I'm missing something really simple.
Typically, generics are used in a situation like this. Here's how I'd do it:
interface Response {
id: number;
}
// Note the generic parameter <R extends Response>
export class GenericController<R extends Response> {
tableName: string = "";
fields: Array<any> = [];
_get = async (req, res) => {
try {
const id = req.body["id"];
const send = async () => {
// The array is now properly typed. You don't know the exact type,
// but you do know the constraint - R is some type of `Response`
let resp: Array<R> = await db(this.tableName).select(this.fields).where("id", id);
if (resp[0] === undefined) {
// some error handling
}
res.status(status.success).json(resp[0]);
};
await send();
} catch (error) {
// some error handling
}
};
}
import { GenericController } from "./_genericController";
interface Response {
id: number;
code: string;
name: string;
type: string;
long: number;
lat: number;
}
const fields = ["code", "name", "type", "long", "lat"];
// Here we tell the GenericController exactly what type of Response it's going to get
class LocationController extends GenericController<Response> {
tableName: string = "location";
fields: Array<any> = fields;
}
const locationController = new LocationController();
const get = async (req, res) => {
await locationController._get(req, res);
};
export { get };
If this is not enough and you wish to somehow know the exact response type you're going to get, I believe the only way is a manual check. For example:
import { LocationResponse } from './locationController';
// ... stuff
// Manual runtime type check
if (this.tableName === 'location') {
// Manual cast
resp = resp as Array<LocationResponse>
}
// ...
You could also check the form of resp[0] (if (resp[0].hasOwnProperty('code')) { ... }) and cast accordingly. There are also nicer ways to write this, but the basic idea remains the same.
Generally, a properly written class should be unaware of any classes that inherit from it. Putting child-class-specific logic into your generic controller is a code smell. Though as always, it all depends on a particular situation.
I'm just getting into Fastify with Typescript and really enjoying it.
However, I'm trying to figure out if I can type the response payload. I have the response schema for serialization working and that may be sufficient, but I have internally typed objects (such as IUser) that it would be nice to have Typescript check against.
The following works great, but I'd like to return an TUser for example and have typescript if I return something different. Using schema merely discludes fields.
interface IUser {
firstname: string,
lastname: string
} // Not in use in example
interface IUserRequest extends RequestGenericInterface {
Params: { username: string };
}
const getUserHandler = async (
req: FastifyRequest<IUserRequest, RawServerBase, IncomingMessage | Http2ServerRequest>
) => {
const { username } = req.params;
return { ... }; // Would like to return instance of IUser
};
app.get<IUserRequest>('/:username', { schema }, helloWorldHandler);
Is there an equivalent of RequestGenericInterface I can extend for the response?
Small Update: It seems that the reply.send() can be used to add the type, but it would be nice for self-documentation sake to provide T higher up.
From the documentation:
Using the two interfaces, define a new API route and pass them as generics. The shorthand route methods (i.e. .get) accept a generic object RouteGenericInterface containing five named properties: Body, Querystring, Params, Headers and Reply.
You can use the Reply type.
interface MiscIPAddressRes {
ipv4: string
}
server.get<{
Reply: MiscIPAddressRes
}>('/misc/ip-address', async (req, res) => {
res
.status(_200_OKAY)
.send({
ipv4: req.ip // this will be typechecked
})
})
After looking at the type definitions, I found out that there is also an alternative way to only type-check the handler (like in Julien TASSIN's answer), like this:
import { FastifyReply, FastifyRequest, RawReplyDefaultExpression, RawRequestDefaultExpression, RawServerDefault } from "fastify";
import { RouteGenericInterface } from "fastify/types/route";
interface IUser {
firstname: string;
lastname: string;
}
interface IUserRequest extends RouteGenericInterface {
Params: { username: string };
Reply: IUser; // put the response payload interface here
}
function getUserHandler(
request: FastifyRequest<IUserRequest>,
reply: FastifyReply<
RawServerDefault,
RawRequestDefaultExpression,
RawReplyDefaultExpression,
IUserRequest // put the request interface here
>
) {
const { username } = request.params;
// do something
// the send() parameter is now type-checked
return reply.send({
firstname: "James",
lastname: "Bond",
});
}
You can also create your own interface with generic to save writing repeating lines, like this:
import { FastifyReply, FastifyRequest, RawReplyDefaultExpression, RawRequestDefaultExpression, RawServerDefault } from "fastify";
import { RouteGenericInterface } from "fastify/types/route";
export interface FastifyReplyWithPayload<Payload extends RouteGenericInterface>
extends FastifyReply<
RawServerDefault,
RawRequestDefaultExpression,
RawReplyDefaultExpression,
Payload
> {}
then use the interface like this:
function getUserHandler(
request: FastifyRequest<IUserRequest>,
reply: FastifyReplyWithPayload<IUserRequest>
) {
const { username } = request.params;
// do something
// the send() parameter is also type-checked like above
return reply.send({
firstname: "James",
lastname: "Bond",
});
}
If you want to type the handler only, you can perform it this way
import { RawReplyDefaultExpression, RawRequestDefaultExpression, RawServerDefault, RouteHandler, RouteHandlerMethod } from "fastify";
const getUserHandler: RouteHandlerMethod<
RawServerDefault,
RawRequestDefaultExpression,
RawReplyDefaultExpression,
{ Reply: IUser; Params: { username: string } }
> = async (
req: FastifyRequest<IUserRequest, RawServerBase, IncomingMessage | Http2ServerRequest>
) => {
const { username } = req.params;
return { ... }; // Would like to return instance of IUser
};
Trying to type these was a truely awful experience. Thanks to the other answers, this is where I ended up. Bit of a code dump to make life easier for others.
request-types.ts
With this I am standardising my response to optionally have data and message.
import {
FastifyReply,
FastifyRequest,
RawReplyDefaultExpression,
RawRequestDefaultExpression,
RawServerDefault,
} from 'fastify';
type ById = {
id: string;
};
type ApiRequest<Body = void, Params = void, Reply = void> = {
Body: Body;
Params: Params;
Reply: { data?: Reply & ById; message?: string };
};
type ApiResponse<Body = void, Params = void, Reply = {}> = FastifyReply<
RawServerDefault,
RawRequestDefaultExpression,
RawReplyDefaultExpression,
ApiRequest<Body, Params, Reply>
>;
type RouteHandlerMethod<Body = void, Params = void, Reply = void> = (
request: FastifyRequest<ApiRequest<Body, Params, Reply>>,
response: ApiResponse<Body, Params, Reply>
) => void;
export type DeleteRequestHandler<ReplyPayload = ById> = RouteHandlerMethod<void, ById, ReplyPayload>;
export type GetRequestHandler<ReplyPayload> = RouteHandlerMethod<void, ById, ReplyPayload>;
export type PostRequestHandler<Payload, ReplyPayload> = RouteHandlerMethod<Payload, void, ReplyPayload>;
export type PatchRequestHandler<Payload, ReplyPayload> = RouteHandlerMethod<Payload, ById, ReplyPayload>;
export type PutRequestHandler<Payload, ReplyPayload> = RouteHandlerMethod<Payload, ById, ReplyPayload>;
Usage
get-account.ts - GetRequestHandler
export const getAccount: GetRequestHandler<AccountResponseDto> = async (request, reply) => {
const { id } = request.params;
...
const account = await Account.findOne....
...
if (account) {
return reply.status(200).send({ data: account });
}
return reply.status(404).send({ message: 'Account not found' });
};
delete-entity.ts - DeleteRequestHandler
export const deleteEntity: DeleteRequestHandler = async (request, reply) => {
const { id } = request.params;
...
// Indicate success by 200 and returning the id of the deleted entity
return reply.status(200).send({ data: { id } });
};
update-account.ts - PatchRequestHandler
export const updateAccount: PatchRequestHandler<
UpdateAccountRequestDto,
AccountResponseDto
> = async (request, reply) => {
const { id } = request.params;
...
return reply.status(200).send({ data: account });
};
register-account-routes.ts - No errors with provided handler.
export const registerAccountRoutes = (app: FastifyInstance) => {
app.get(EndPoints.ACCOUNT_BY_ID, getAccount);
app.patch(EndPoints.ACCOUNT_BY_ID, updateAccount);
app.post(EndPoints.ACCOUNTS_AUTHENTICATE, authenticate);
app.put(EndPoints.ACCOUNTS, createAccount);
};
Im playing around with nestjs and mongoose.
The code:
class BrevesController {
constructor(private readonly brevesService: BrevesService) { }
// Here is used BreveOwnerGuard(1)
#UseGuards(JwtAuthGuard, BreveOwnerGuard)
#Get(':breveId')
// Here is used ValidateObjectId(3)
async getById(#Param('breveId', ValidateObjectId) id: string) {
return await this.brevesService.getById(id)
}
}
class BreveOwnerGuard {
constructor(private readonly brevesService: BrevesService) { }
async canActivate(context: ExecutionContext) {
const req = context.switchToHttp().getRequest()
const {user, params} = req
const {breveId} = params
// This is executed before ValidateObjectId in getById
// route handler and unknown error is thrown but we
// have pipe for this.(2)
const breve = await this.brevesService.getById(breveId)
const breveCreatorId = breve.creatorId.toString()
const userId = user.id
return breveCreatorId === userId
}
}
So after request /breves/:breveId with invalid object id, the BreveOwnerGuard is executed before ValidateObjectId and unknown error is thrown.
Is there a way for this flow to validate the ObjectId before BreveOwnerGuard ?
Or what should I do in this case? What is expected ?
Guards are executed after each middleware, but before any interceptor or pipe.
Source: Guard Docs (emphasis by me)
Not much you can do other than change the ResourceOwnerGuard to a pipe or the ValidateObjectId into a Guard.