typedrequest/ts/typedrequest.classes.typedrouter.ts
2022-03-29 14:50:39 +02:00

117 lines
3.8 KiB
TypeScript

import * as plugins from './typedrequest.plugins.js';
import { TypedHandler } from './typedrequest.classes.typedhandler.js';
import { TypedRequest } from './typedrequest.classes.typedrequest.js';
/**
* A typed router decides on which typed handler to call based on the method
* specified in the typed request
* This is thought for reusing the same url endpoint for different methods
*/
export class TypedRouter {
public routerMap = new plugins.lik.ObjectMap<TypedRouter>();
public handlerMap = new plugins.lik.ObjectMap<
TypedHandler<any & plugins.typedRequestInterfaces.ITypedRequest>
>();
public fireEventInterestMap = new plugins.lik.InterestMap<
string,
plugins.typedRequestInterfaces.ITypedRequest
>((correlationId: string) => correlationId);
/**
* adds the handler to the routing map
* @param typedHandlerArg
*/
public addTypedHandler<T extends plugins.typedRequestInterfaces.ITypedRequest> (
typedHandlerArg: TypedHandler<T>
) {
// lets check for deduplication
const existingTypedHandler = this.getTypedHandlerForMethod(typedHandlerArg.method);
if (existingTypedHandler) {
throw new Error(
`a TypedHandler for ${typedHandlerArg.method} alredy exists! Can't add another one.`
);
}
this.handlerMap.add(typedHandlerArg);
}
/**
* adds another sub typedRouter
* @param typedRequest
*/
public addTypedRouter (typedRouterArg: TypedRouter) {
const routerExists = this.routerMap.findSync(routerArg => routerArg === typedRouterArg)
if (!routerExists) {
this.routerMap.add(typedRouterArg);
typedRouterArg.addTypedRouter(this);
}
}
public checkForTypedHandler (methodArg: string): boolean {
return !!this.getTypedHandlerForMethod(methodArg);
}
/**
* gets a typed Router from the router chain, upstream and downstream
* @param methodArg
* @param checkUpstreamRouter
*/
public getTypedHandlerForMethod (
methodArg: string,
checkedRouters: TypedRouter[] = []
): TypedHandler<any> {
checkedRouters.push(this);
let typedHandler: TypedHandler<any>;
typedHandler = this.handlerMap.findSync((handler) => {
return handler.method === methodArg;
});
if (!typedHandler) {
this.routerMap.getArray().forEach((typedRouterArg) => {
if (!typedHandler && !checkedRouters.includes(typedRouterArg)) {
typedHandler = typedRouterArg.getTypedHandlerForMethod(methodArg, checkedRouters);
}
});
}
return typedHandler;
}
/**
* if typedrequest object has correlation.phase === 'request' -> routes a typed request object to a handler
* if typedrequest object has correlation.phase === 'response' -> routes a typed request object to request fire event
* @param typedRequestArg
*/
public async routeAndAddResponse<T extends plugins.typedRequestInterfaces.ITypedRequest = plugins.typedRequestInterfaces.ITypedRequest> (typedRequestArg: T): Promise<T> {
if (typedRequestArg?.correlation?.phase === 'request') {
const typedHandler = this.getTypedHandlerForMethod(typedRequestArg.method);
if (!typedHandler) {
console.log(`Cannot find handler for methodname ${typedRequestArg.method}`);
typedRequestArg.error = {
text: 'There is no available method for this call on the server side',
data: {},
};
typedRequestArg.correlation.phase = 'response';
return typedRequestArg;
}
typedRequestArg = await typedHandler.addResponse(typedRequestArg);
return typedRequestArg;
} else if (typedRequestArg?.correlation?.phase === 'response') {
this.fireEventInterestMap
.findInterest(typedRequestArg.correlation.id)
?.fullfillInterest(typedRequestArg);
return null;
} else {
console.log('received weirdly shaped request');
console.log(typedRequestArg);
return null
}
}
}