als-send-file/tests/etag.test.js

file serving with advanced options for caching, headers, and error handling, compatible with Express middleware.

const http = require('http');
const { describe, it, beforeEach } = require('node:test');
const assert = require('node:assert');
const generateETag = require('../lib/etag');

describe('ETag Tests', () => {
   let request, response, stats;

   beforeEach(() => {
      stats = { mtimeMs: Date.now(), mtime: new Date(), ino: 12345 };
      request = new http.IncomingMessage({});
      response = new http.ServerResponse({});
      response.setHeader = function (key, value) {
         this.headers = this.headers || {};
         this.headers[key] = value;
      };
      response.end = function () {
         this.ended = true;
      };
   });

   it('should set Last-Modified and ETag headers', () => {
      generateETag(request, response, stats);
      assert(response.headers['Last-Modified'] === stats.mtime.toUTCString())
      assert.strictEqual(response.headers['ETag'], stats.ino.toString() + stats.mtimeMs.toString());
   });

   it('should set not modified if If-Modified-Since matches', () => {
      request.headers['if-modified-since'] = stats.mtime.toString();
      const result = generateETag(request, response, stats);
      assert.strictEqual(result, true);
      assert.strictEqual(response.statusCode, 304);
      assert.strictEqual(response.ended, true);
   });

   it('should generate ETag and set not modified if ETag matches', () => {
      request.headers['if-none-match'] = stats.ino + stats.mtimeMs.toString();
      const result = generateETag(request, response, stats);
      const {statusCode,ended} = response
      assert.strictEqual(result, true);
      assert.strictEqual(response.statusCode, 304);
      assert.strictEqual(response.ended, true);
   });

   it('should not set not modified if If-Modified-Since does not match', () => {
      request.headers['if-modified-since'] = new Date(stats.mtimeMs - 10000).toUTCString();
      const result = generateETag(request, response, stats);
      assert.strictEqual(result, false);
   });

   it('should not set not modified if ETag does not match', () => {
      request.headers['if-none-match'] = 'wrong';
      const result = generateETag(request, response, stats);
      assert.strictEqual(result, false);
   });

   it('should not set not modified if If-Modified-Since is invalid', () => {
      request.headers['if-modified-since'] = 'invalid-date';
      const result = generateETag(request, response, stats);
      assert.strictEqual(result, false);
   });

   it('should not set not modified if both If-None-Match and If-Modified-Since are missing', () => {
      const result = generateETag(request, response, stats);
      assert.strictEqual(result, false);
   });

});