refactor: rename email-server-worker to email-worker

Rename directory from email-server-worker to email-worker for clarity and brevity. Update all references in CLAUDE.md documentation.

email-worker/src/routes/errorRouter.ts

@@ -0,0 +1,81 @@
+import { ErrorRequestHandler, Request, Response } from "express";
+import createHttpError, { HttpError } from "http-errors";
+import { createLogger } from '../lib/logger';
+import { NgitLocals } from "../types/NgitLocals";
+import { failedRequestCounter } from "../lib/metricsCounters";
+import { SupportedRoutes } from "../types/enums/SupportedRoutes";
+
+const consoleLog = createLogger("server:server");
+
+/**
+ * Router koji se zadnji poziva, a koji sastavlja odgovor u slučaju greške
+ * @param err 
+ * @param req 
+ * @param res 
+ * @param next 
+ */
+export const errorRouter:ErrorRequestHandler = async (err:HttpError, req, res, next) => {
+
+    const requestPath = req.path as SupportedRoutes;
+
+    // kako je ovaj error handler dosta složen, moguće je da negdje baci grešku
+    // > zato je zamotan u try-catch
+    // > na taj način osiguravam da neće srušiti cijeli proces
+    try {
+
+        let { name:errorLogName, message:errorLogText } = err;
+        let responseBody:string = "";
+
+        switch(err.status) {
+            case 400:
+                responseBody = 'bad request';
+                break;
+            case 401:
+                responseBody = 'unauthorized';
+                break;
+            case 403:
+                responseBody = 'forbidden';
+                break;
+            case 404:
+                consoleLog(`page not found ${req.method} ${requestPath}`)
+                responseBody = 'page not found';
+                errorLogText = `page ${requestPath} not found`;
+                break;
+            case 500:
+                responseBody = "internal server error";
+                errorLogText = err.message;
+                break;
+            default:
+                responseBody = err.name;
+                errorLogText = `err.status=${err.status};err.name=${err.name};err.message=${err.message}`;
+        }
+
+        consoleLog(`${errorLogName}:${errorLogText}`);
+        
+        // `headersSent` će biti TRUE ako je router kod kojeg se dogodila greška već poslao header-e
+        // > ako ih probam ponovo postaviti, to će baciti grešku ... a to ovdje mogu izbjeći
+        if(!res.headersSent) {
+            res.status(err.status);
+            res.setHeader('Content-Type', "text/html");
+            res.end(responseBody);
+        } else {
+            // AKO nije pozvan `end` - pozovi ga i završi obradu zahtjeva
+            // ... u suprotnom će konekcija ostati otvorena do timeout-a
+            if(!res.writableEnded) {
+                res.end();
+            }
+        }
+
+    } catch(ex:any) {
+        // ovu grešku će obraditi `finalErrorRouter`
+        next(createHttpError(500, ex));
+    }
+
+    // ne mogu dopustiti da prometheus client sruši server
+    try  {
+        failedRequestCounter.inc({ path: requestPath, status: err.status });
+        (res.locals as NgitLocals).stopPrometheusTimer({ path: req.path, status: err.status });
+    } catch(ex:any) {
+        console.error(ex);
+    }
+};

email-worker/src/routes/finalErrorRouter.ts

@@ -0,0 +1,34 @@
+import { ErrorRequestHandler, Request, Response } from "express";
+import { HttpError } from "http-errors";
+import { createLogger } from '../lib/logger';
+import { NgitLocals } from "../types/NgitLocals";
+
+const consoleLog = createLogger("server:server");
+
+/**
+ * Router koji se izvršava u slučaju grube greške koja nije obrađena nigdje prije
+ * @param err error objekt
+ * @param req express request
+ * @param res express response
+ * @param next 
+ */
+export const finalErrorRouter:ErrorRequestHandler = async (err:HttpError, req, res, next) => {
+
+    const errorLogText:string = JSON.stringify({ message:err.message, name:err.name, stack:err.stack });
+
+    consoleLog(`Server Error ${err.status}\n${errorLogText}`);          
+
+    // `headersSent` će biti TRUE ako je router kod kojeg se dogodila greška već poslao header-e
+    // > ako ih probam ponovo postaviti, to će baciti grešku i u ovom slučaju SRUŠITI SERVER - to ne smijemo dopustiti
+    if(!res.headersSent) {
+        res.status(err.status);
+        res.setHeader('Content-Type', "text/html");
+        res.end(`unhandled server error`);
+    } else {
+        // AKO nije pozvan `end` - pozovi ga i završi obradu zahtjeva
+        // ... u suprotnom će konekcija ostati otvorena do timeout-a
+        if(!res.writableEnded) {
+            res.end();
+        }
+    }
+};

email-worker/src/routes/healthcheckRouter.ts

@@ -0,0 +1,35 @@
+import { RequestHandler, Router } from "express";
+import { workerRunnerInfo } from "../workRunner";
+import { coalesce } from "../lib/initTools";
+
+const PULL_INTERVAL = parseInt(coalesce(process.env.PULL_INTERVAL, "10000"));
+
+/** Maximum time between two worker jobs */
+const MAX_WORKER_LATENCY = PULL_INTERVAL * 2.5;
+
+/**
+ * Router koji se izvršava u slučaju grube greške koja nije obrađena nigdje prije
+ * @param req express request
+ * @param res express response
+ * @param next 
+ */
+export const healthcheckRouter:RequestHandler = async (req, res, next) => {
+    const workerLatency = Date.now() - workerRunnerInfo.lastWorkTime;
+
+    if(workerLatency > MAX_WORKER_LATENCY) {
+        const msg = `No work done in ${workerLatency}ms. Last worker status = "${workerRunnerInfo.status}"`;
+
+        console.warn(msg)
+
+        res.status(500);
+        res.setHeader('Content-Type', 'text/plain');
+        res.end(msg);
+    } else {
+        res.status(200);
+        res.setHeader('Content-Type', 'text/plain');
+        res.end('OK');
+    }
+};
+
+export const pingRouter = Router();
+pingRouter.get('/', healthcheckRouter);

email-worker/src/routes/metricsRouter.ts

@@ -0,0 +1,19 @@
+import { Router, NextFunction, Request, Response } from "express";
+import createError from 'http-errors';
+import { register } from 'prom-client';
+import { createLogger } from '../lib/logger';
+
+const logger = createLogger("server:metrics");
+
+export const metricsRouter = Router();
+
+metricsRouter.get('/', async (req:Request, res:Response, next:NextFunction) => {
+    // ne mogu dopustiti da prometheus client sruši server
+    try {
+        logger(`⚡️[server]: GET /metrics`);
+        res.set('Content-Type', register.contentType);
+        res.end(await register.metrics());
+    } catch(ex:any) {
+        next(createError(500, (ex as Error).message));
+    }
+});

email-worker/src/routes/pingRouter.ts

@@ -0,0 +1,16 @@
+import { RequestHandler, Router } from "express";
+
+/**
+ * Router koji se izvršava u slučaju grube greške koja nije obrađena nigdje prije
+ * @param req express request
+ * @param res express response
+ * @param next 
+ */
+export const pingRequestHandler:RequestHandler = async (req, res, next) => {
+    res.status(200);
+    res.setHeader('Content-Type', 'text/plain');
+    res.end('PONG');
+};
+
+export const pingRouter = Router();
+pingRouter.get('/', pingRequestHandler);