typedrequest/ts/typedrequest.classes.typedrouter.ts
2020-10-06 21:33:46 +00:00

125 lines
3.9 KiB
TypeScript

import * as plugins from './typedrequest.plugins';
import { TypedHandler } from './typedrequest.classes.typedhandler';
import { TypedRequest } from './typedrequest.classes.typedrequest';
/**
* 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 upstreamTypedRouter: TypedRouter;
public routerMap = new plugins.lik.ObjectMap<TypedRouter>();
public handlerMap = new plugins.lik.ObjectMap<
TypedHandler<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) {
this.routerMap.add(typedRouterArg);
}
public setUpstreamTypedRouter(typedRouterArg: TypedRouter) {
this.upstreamTypedRouter = typedRouterArg;
}
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,
checkUpstreamRouter = true
): TypedHandler<any> {
let typedHandler: TypedHandler<any>;
if (this.upstreamTypedRouter && checkUpstreamRouter) {
typedHandler = this.upstreamTypedRouter.getTypedHandlerForMethod(methodArg);
} else {
typedHandler = this.handlerMap.find((handler) => {
return handler.method === methodArg;
});
if (!typedHandler) {
this.routerMap.getArray().forEach((typedRouter) => {
if (!typedHandler) {
typedHandler = typedRouter.getTypedHandlerForMethod(methodArg, false);
}
});
}
}
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(typedRequestArg: plugins.typedRequestInterfaces.ITypedRequest) {
if (!typedRequestArg?.correlation?.phase || 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: {},
};
return typedRequestArg;
}
typedRequestArg = await typedHandler.addResponse(typedRequestArg);
} else if (typedRequestArg.correlation.phase === 'response') {
this.fireEventInterestMap
.findInterest(typedRequestArg.correlation.id)
?.fullfillInterest(typedRequestArg);
} else {
console.log('received weirdly shaped request');
console.log(typedRequestArg);
return {}
}
return {
...typedRequestArg,
...{
method: 'nullPathFromResponse',
},
};
}
}