@nimpl/ab-tests/dist/middleware.js

A package for conducting A/B tests on a website using middleware

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.createMiddleware = void 0;
const server_1 = require("next/server");
const parse_value_1 = require("./lib/utils/parse-value");
const find_test_1 = require("./lib/find-test");
const cookies_1 = require("./lib/data/cookies");
const createMiddleware = ({ tests, cookieLifeTime }) => (request) => {
    const pathname = request.nextUrl.pathname;
    const testCookieRow = request.cookies.get(cookies_1.COOKIE_NAME)?.value;
    const testCookieTmpRow = request.cookies.get(cookies_1.COOKIE_NAME_TMP)?.value;
    const testCookieBase = testCookieRow || testCookieTmpRow;
    if (testCookieBase === "0")
        return server_1.NextResponse.next();
    const prevTestCookie = (0, parse_value_1.parseValue)(testCookieBase);
    const testResult = (0, find_test_1.findTest)(tests, request, prevTestCookie);
    if (testResult) {
        const { id, variantIndex, destination, type = "rewrite", status } = testResult;
        let next;
        if (type === "rewrite") {
            next = server_1.NextResponse.rewrite(new URL(destination, request.url), { status: status || 200 });
        }
        else {
            next = server_1.NextResponse.redirect(new URL(destination, request.url), { status: status || 307 });
        }
        // We save for the session so that files are uploaded for the same variant
        next.cookies.set(cookies_1.COOKIE_NAME, JSON.stringify({ id, variantIndex }));
        // If cookieLifeTime is specified - we save it in case of a session change, but if cookies have already been - it means that it is no longer necessary to add it
        if (cookieLifeTime && !testCookieBase) {
            next.cookies.set(cookies_1.COOKIE_NAME_TMP, JSON.stringify({ id, variantIndex }), { maxAge: cookieLifeTime });
        }
        return next;
    }
    const next = server_1.NextResponse.next();
    // Protection from the participation of the script for the page for non-participating users, since the script has the same path as the page itself
    next.cookies.set(cookies_1.COOKIE_NAME, "0", { path: pathname });
    return next;
};
exports.createMiddleware = createMiddleware;