log4js-node/test/tap/connect-logger-test.js

const { test } = require("tap");
const EE = require("events").EventEmitter;
const levels = require("../../lib/levels");

class MockLogger {
  constructor() {
    this.level = levels.TRACE;
    this.messages = [];
    this.log = function(level, message) {
      this.messages.push({ level, message });
    };
    this.isLevelEnabled = function(level) {
      return level.isGreaterThanOrEqualTo(this.level);
    };
  }
}

function MockRequest(remoteAddr, method, originalUrl, headers, url, custom) {
  this.socket = { remoteAddress: remoteAddr };
  this.originalUrl = originalUrl;
  this.url = url;
  this.method = method;
  this.httpVersionMajor = "5";
  this.httpVersionMinor = "0";
  this.headers = headers || {};

  if (custom) {
    for (const key of Object.keys(custom)) {
      this[key] = custom[key];
    }
  }

  const self = this;
  Object.keys(this.headers).forEach(key => {
    self.headers[key.toLowerCase()] = self.headers[key];
  });
}

class MockResponse extends EE {
  constructor() {
    super();
    this.cachedHeaders = {};
  }

  end() {
    this.emit("finish");
  }

  setHeader(key, value) {
    this.cachedHeaders[key.toLowerCase()] = value;
  }

  getHeader(key) {
    return this.cachedHeaders[key.toLowerCase()];
  }

  writeHead(code /* , headers */) {
    this.statusCode = code;
  }
}

function request(
  cl,
  method,
  originalUrl,
  code,
  reqHeaders,
  resHeaders,
  next,
  url,
  custom = undefined
) {
  const req = new MockRequest(
    "my.remote.addr",
    method,
    originalUrl,
    reqHeaders,
    url,
    custom
  );
  const res = new MockResponse();
  if (next) {
    next = next.bind(null, req, res, () => {});
  } else {
    next = () => {};
  }
  cl(req, res, next);
  res.writeHead(code, resHeaders);
  res.end("chunk", "encoding");
}

test("log4js connect logger", batch => {
  const clm = require("../../lib/connect-logger");
  batch.test("getConnectLoggerModule", t => {
    t.type(clm, "function", "should return a connect logger factory");

    t.test(
      'should take a log4js logger and return a "connect logger"',
      assert => {
        const ml = new MockLogger();
        const cl = clm(ml);

        assert.type(cl, "function");
        assert.end();
      }
    );

    t.test("log events", assert => {
      const ml = new MockLogger();
      const cl = clm(ml);
      request(cl, "GET", "http://url", 200);

      const { messages } = ml;
      assert.type(messages, "Array");
      assert.equal(messages.length, 1);
      assert.ok(levels.INFO.isEqualTo(messages[0].level));
      assert.include(messages[0].message, "GET");
      assert.include(messages[0].message, "http://url");
      assert.include(messages[0].message, "my.remote.addr");
      assert.include(messages[0].message, "200");
      assert.end();
    });

    t.test("log events with level below logging level", assert => {
      const ml = new MockLogger();
      ml.level = levels.FATAL;
      const cl = clm(ml);
      request(cl, "GET", "http://url", 200);

      assert.type(ml.messages, "Array");
      assert.equal(ml.messages.length, 0);
      assert.end();
    });

    t.test("log events with non-default level and custom format", assert => {
      const ml = new MockLogger();
      ml.level = levels.INFO;
      const cl = clm(ml, { level: levels.WARN, format: ":method :url" });
      request(cl, "GET", "http://url", 200);

      const { messages } = ml;
      assert.type(messages, Array);
      assert.equal(messages.length, 1);
      assert.ok(levels.WARN.isEqualTo(messages[0].level));
      assert.equal(messages[0].message, "GET http://url");
      assert.end();
    });

    t.test("adding multiple loggers should only log once", assert => {
      const ml = new MockLogger();
      ml.level = levels.INFO;
      const cl = clm(ml, { level: levels.WARN, format: ":method :url" });
      const nextLogger = clm(ml, { level: levels.INFO, format: ":method" });
      request(cl, "GET", "http://url", 200, null, null, nextLogger);

      const { messages } = ml;
      assert.type(messages, Array);
      assert.equal(messages.length, 1);
      assert.ok(levels.WARN.isEqualTo(messages[0].level));
      assert.equal(messages[0].message, "GET http://url");

      assert.end();
    });
    t.end();
  });

  batch.test("logger with options as string", t => {
    const ml = new MockLogger();
    ml.level = levels.INFO;
    const cl = clm(ml, ":method :url");
    request(cl, "POST", "http://meh", 200);

    const { messages } = ml;
    t.equal(messages[0].message, "POST http://meh");
    t.end();
  });

  batch.test("auto log levels", t => {
    const ml = new MockLogger();
    ml.level = levels.INFO;
    const cl = clm(ml, { level: "auto", format: ":method :url" });
    request(cl, "GET", "http://meh", 200);
    request(cl, "GET", "http://meh", 201);
    request(cl, "GET", "http://meh", 302);
    request(cl, "GET", "http://meh", 404);
    request(cl, "GET", "http://meh", 500);

    const { messages } = ml;
    t.test("should use INFO for 2xx", assert => {
      assert.ok(levels.INFO.isEqualTo(messages[0].level));
      assert.ok(levels.INFO.isEqualTo(messages[1].level));
      assert.end();
    });

    t.test("should use WARN for 3xx", assert => {
      assert.ok(levels.WARN.isEqualTo(messages[2].level));
      assert.end();
    });

    t.test("should use ERROR for 4xx", assert => {
      assert.ok(levels.ERROR.isEqualTo(messages[3].level));
      assert.end();
    });

    t.test("should use ERROR for 5xx", assert => {
      assert.ok(levels.ERROR.isEqualTo(messages[4].level));
      assert.end();
    });
    t.end();
  });

  batch.test("logger with status code rules applied", t => {
    const ml = new MockLogger();
    ml.level = levels.DEBUG;
    const clr = [
      { codes: [201, 304], level: levels.DEBUG.toString() },
      { from: 200, to: 299, level: levels.DEBUG.toString() },
      { from: 300, to: 399, level: levels.INFO.toString() }
    ];
    const cl = clm(ml, {
      level: "auto",
      format: ":method :url",
      statusRules: clr
    });
    request(cl, "GET", "http://meh", 200);
    request(cl, "GET", "http://meh", 201);
    request(cl, "GET", "http://meh", 302);
    request(cl, "GET", "http://meh", 304);
    request(cl, "GET", "http://meh", 404);
    request(cl, "GET", "http://meh", 500);

    const { messages } = ml;
    t.test("should use DEBUG for 2xx", assert => {
      assert.ok(levels.DEBUG.isEqualTo(messages[0].level));
      assert.ok(levels.DEBUG.isEqualTo(messages[1].level));
      assert.end();
    });

    t.test("should use WARN for 3xx, DEBUG for 304", assert => {
      assert.ok(levels.INFO.isEqualTo(messages[2].level));
      assert.ok(levels.DEBUG.isEqualTo(messages[3].level));
      assert.end();
    });

    t.test("should use ERROR for 4xx", assert => {
      assert.ok(levels.ERROR.isEqualTo(messages[4].level));
      assert.end();
    });

    t.test("should use ERROR for 5xx", assert => {
      assert.ok(levels.ERROR.isEqualTo(messages[5].level));
      assert.end();
    });
    t.end();
  });

  batch.test("format using a function", t => {
    const ml = new MockLogger();
    ml.level = levels.INFO;
    const cl = clm(ml, () => "I was called");
    request(cl, "GET", "http://blah", 200);

    t.equal(ml.messages[0].message, "I was called");
    t.end();
  });

  batch.test("format using a function that also uses tokens", t => {
    const ml = new MockLogger();
    ml.level = levels.INFO;
    const cl = clm(
      ml,
      (req, res, tokenReplacer) => `${req.method} ${tokenReplacer(":status")}`
    );
    request(cl, "GET", "http://blah", 200);

    t.equal(ml.messages[0].message, "GET 200");
    t.end();
  });

  batch.test(
    "format using a function, but do not log anything if the function returns nothing",
    t => {
      const ml = new MockLogger();
      ml.level = levels.INFO;
      const cl = clm(ml, () => null);
      request(cl, "GET", "http://blah", 200);

      t.equal(ml.messages.length, 0);
      t.end();
    }
  );

  batch.test("format that includes request headers", t => {
    const ml = new MockLogger();
    ml.level = levels.INFO;
    const cl = clm(ml, ":req[Content-Type]");
    request(cl, "GET", "http://blah", 200, {
      "Content-Type": "application/json"
    });

    t.equal(ml.messages[0].message, "application/json");
    t.end();
  });

  batch.test("format that includes response headers", t => {
    const ml = new MockLogger();
    ml.level = levels.INFO;
    const cl = clm(ml, ":res[Content-Type]");
    request(cl, "GET", "http://blah", 200, null, {
      "Content-Type": "application/cheese"
    });

    t.equal(ml.messages[0].message, "application/cheese");
    t.end();
  });

  batch.test("url token should check originalUrl and url", t => {
    const ml = new MockLogger();
    const cl = clm(ml, ":url");
    request(cl, "GET", null, 200, null, null, null, "http://cheese");

    t.equal(ml.messages[0].message, "http://cheese");
    t.end();
  });

  batch.test("log events with custom token", t => {
    const ml = new MockLogger();
    ml.level = levels.INFO;
    const cl = clm(ml, {
      level: levels.INFO,
      format: ":method :url :custom_string",
      tokens: [
        {
          token: ":custom_string",
          replacement: "fooBAR"
        }
      ]
    });
    request(cl, "GET", "http://url", 200);

    t.type(ml.messages, "Array");
    t.equal(ml.messages.length, 1);
    t.ok(levels.INFO.isEqualTo(ml.messages[0].level));
    t.equal(ml.messages[0].message, "GET http://url fooBAR");
    t.end();
  });

  batch.test("log events with custom override token", t => {
    const ml = new MockLogger();
    ml.level = levels.INFO;
    const cl = clm(ml, {
      level: levels.INFO,
      format: ":method :url :date",
      tokens: [
        {
          token: ":date",
          replacement: "20150310"
        }
      ]
    });
    request(cl, "GET", "http://url", 200);

    t.type(ml.messages, "Array");
    t.equal(ml.messages.length, 1);
    t.ok(levels.INFO.isEqualTo(ml.messages[0].level));
    t.equal(ml.messages[0].message, "GET http://url 20150310");
    t.end();
  });

  batch.test("log events with custom format", t => {
    const ml = new MockLogger();
    const body = { say: "hi!" };
    ml.level = levels.INFO;
    const cl = clm(ml, {
      level: levels.INFO,
      format: (req, res, format) =>
        format(`:method :url ${JSON.stringify(req.body)}`)
    });
    request(
      cl,
      "POST",
      "http://url",
      200,
      { "Content-Type": "application/json" },
      null,
      null,
      null,
      { body }
    );

    t.ok(levels.INFO.isEqualTo(ml.messages[0].level));
    t.equal(ml.messages[0].message, `POST http://url ${JSON.stringify(body)}`);
    t.end();
  });

  batch.test(
    "handle weird old node versions where socket contains socket",
    t => {
      const ml = new MockLogger();
      const cl = clm(ml, ":remote-addr");
      const req = new MockRequest(null, "GET", "http://blah");
      req.socket = { socket: { remoteAddress: "this is weird" } };

      const res = new MockResponse();
      cl(req, res, () => {});
      res.writeHead(200, {});
      res.end("chunk", "encoding");

      t.equal(ml.messages[0].message, "this is weird");
      t.end();
    }
  );

  batch.end();
});