61 lines
1.6 KiB
TypeScript
61 lines
1.6 KiB
TypeScript
|
import { RequestCanceller } from 'services/HTTPService';
|
||
|
|
|
||
|
|
interface RequestQueueItem {
|
||
|
|
request: (canceller?: RequestCanceller) => any;
|
||
|
|
callback: (response) => void;
|
||
|
|
isCanceled: { status: boolean };
|
||
|
|
canceller: { exec: () => void };
|
||
|
|
}
|
||
|
|
|
||
|
|
export default class QueueService {
|
||
|
|
private requestQueue: RequestQueueItem[] = [];
|
||
|
|
|
||
|
|
private requestInProcessing = 0;
|
||
|
|
|
||
|
|
constructor(private maxParallelProcesses: number) {}
|
||
|
|
|
||
|
|
public queueUpRequest(request: () => any) {
|
||
|
|
const isCanceled = { status: false };
|
||
|
|
const canceller: RequestCanceller = {
|
||
|
|
exec: () => {
|
||
|
|
isCanceled.status = true;
|
||
|
|
},
|
||
|
|
};
|
||
|
|
|
||
|
|
const response = new Promise<string>((resolve) => {
|
||
|
|
this.requestQueue.push({
|
||
|
|
request,
|
||
|
|
callback: resolve,
|
||
|
|
isCanceled,
|
||
|
|
canceller,
|
||
|
|
});
|
||
|
|
this.pollQueue();
|
||
|
|
});
|
||
|
|
|
||
|
|
return { response, canceller };
|
||
|
|
}
|
||
|
|
|
||
|
|
async pollQueue() {
|
||
|
|
if (this.requestInProcessing < this.maxParallelProcesses) {
|
||
|
|
this.requestInProcessing++;
|
||
|
|
await this.processQueue();
|
||
|
|
this.requestInProcessing--;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
public async processQueue() {
|
||
|
|
while (this.requestQueue.length > 0) {
|
||
|
|
const queueItem = this.requestQueue.pop();
|
||
|
|
let response: string;
|
||
|
|
|
||
|
|
if (queueItem.isCanceled.status) {
|
||
|
|
response = null;
|
||
|
|
} else {
|
||
|
|
response = await queueItem.request(queueItem.canceller);
|
||
|
|
}
|
||
|
|
queueItem.callback(response);
|
||
|
|
await this.processQueue();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|