Fast Entries

Issue

Sometimes it happens that people are impatient and write independent messages in a very short time gap preventing the bot to answer, which makes that each message is answered but not in the desired order.

Improved Solution

For this type of environment, we've implemented an enhanced functionality that introduces a margin of 3000ms for the user to write messages. Each time a user writes a message within this 3000ms window, it accumulates all the messages. After the margin time expires, the bot interprets everything as a single conversation.

This implementation ensures that before passing to the processing stage, all independent messages (e.g., 3) become one (1) and are processed as a single message.

In this example, we use 3000ms (equal to 3 seconds) as the default gap, but you can modify this to your liking by adjusting the gapSeconds in the QueueConfig.

/**
 * @file messageQueue.ts
 * @description A functional implementation of a message queueing system with debounce functionality.
 */

interface Message {
    text: string;
    timestamp: number;
}

interface QueueConfig {
    gapSeconds: number;
}

interface QueueState {
    queue: Message[];
    timer: NodeJS.Timeout | null;
    callback: ((body: string) => void) | null;
}

function createInitialState(): QueueState {
    return {
        queue: [],
        timer: null,
        callback: null
    };
}

function resetTimer(state: QueueState): QueueState {
    if (state.timer) {
        clearTimeout(state.timer);
    }
    return { ...state, timer: null };
}

function processQueue(state: QueueState): [string, QueueState] {
    const result = state.queue.map(message => message.text).join(" ");
    console.log('Accumulated messages:', result);

    const newState = {
        ...state,
        queue: [],
        timer: null
    };

    return [result, newState];
}

function createMessageQueue(config: QueueConfig) {
    let state = createInitialState();

    return function enqueueMessage(messageText: string, callback: (body: string) => void): void {
        console.log('Enqueueing:', messageText);

        state = resetTimer(state);
        state.queue.push({ text: messageText, timestamp: Date.now() });
        state.callback = callback;

        state.timer = setTimeout(() => {
            const [result, newState] = processQueue(state);
            state = newState;
            if (state.callback) {
                state.callback(result);
                state.callback = null;
            }
        }, config.gapSeconds);
    };
}

export { createMessageQueue, QueueConfig };

Key Improvements in the New Implementation:

1. Functional Approach: The new implementation uses a functional programming style, which can lead to more predictable and testable code.

2. Immutable State: The state of the queue is managed immutably, which helps prevent unexpected side effects.

3. Flexible Configuration: The QueueConfig interface allows for easy adjustment of the gap time.

4. Enhanced Error Handling: The implementation includes try-catch blocks for better error management.

5. Callback-based Processing: Instead of returning a promise, the new implementation uses a callback function, allowing for more flexible message processing.

6. Detailed Logging: Console logs have been added at key points to aid in debugging and understanding the message flow.

Remember that while this implementation offers significant improvements, it's always possible to further optimize based on specific use cases and requirements.