somod-chat-service/build/serverless/functions/wsOnMessage.js

Serverless Chat Service from SOMOD

import { RouteBuilder } from "somod-websocket-extension";
import { putMessage, validateIncomingMessage } from "../../lib/message";
import { v1 as v1uuid } from "uuid";
import { handleSessionToken } from "../../lib/sessionUtil";
import { getUserIdFromEvent } from "../../lib/getUserIdFromEvent";
const builder = new RouteBuilder();
builder.add("$default", async (message, event) => {
    const userId = getUserIdFromEvent(event);
    const messageValidationError = await validateIncomingMessage(message.body, userId);
    if (messageValidationError) {
        return messageValidationError;
    }
    const sessionIdResult = await handleSessionToken(userId, message.body.threadId, message.body.type, message.body.action, message.body.sessionToken);
    if (sessionIdResult.error) {
        return {
            statusCode: 400,
            headers: { "Content-Type": "application/json; charset=utf-8" },
            body: JSON.stringify({
                message: sessionIdResult.error,
                threadId: message.body.threadId,
                sessionRequiredTill: sessionIdResult.sessionRequiredTill
            })
        };
    }
    // eslint-disable-next-line @typescript-eslint/no-unused-vars
    const { wsMsgId, sessionToken, ...msg } = message.body;
    const actions = ["sessionStart", "sessionExtend", "sessionEnd"];
    const messageResult = await putMessage(process.env.MESSAGE_BOX_TABLE_NAME + "", userId, {
        ...msg,
        sessionId: sessionIdResult.sessionId,
        from: userId,
        id: v1uuid().split("-").join(""),
        sentAt: Date.now(),
        ...(actions.includes(message.body.action)
            ? { sessionToken: sessionToken }
            : {})
    });
    return {
        statusCode: 200,
        headers: { "Content-Type": "application/json; charset=utf-8" },
        body: JSON.stringify({
            wsMsgId,
            type: "ack",
            id: messageResult.id,
            seqNo: messageResult.seqNo,
            sentAt: messageResult.sentAt,
            from: messageResult.from
        })
    };
});
export default builder.getHandler();