configure.spec.js

const path = require("path");
const log4js = require("log4js");
const chai = require("chai");
const expect = chai.expect;

describe("Startup configuration", function() {
    const configuration = require("./configure");
    const log4jsFiles = path.dirname(require.resolve("log4js"));
    const layouts = require(path.join(log4jsFiles, "layouts"));
    const LoggingEvent = require(path.join(log4jsFiles, "LoggingEvent"));

    describe("JSON layout", function() {
        let layout;

        beforeEach(function() {
            layout = layouts.layout("json");
        });

        it("was registered", function() {
            expect(layout).to.exist;
        });

        it("generates valid JSON", function() {
            let event = new LoggingEvent("foo", log4js.levels.INFO, []);
            let result = layout(event);

            expect(() => JSON.parse(result)).not.to.throw();
        });

        it("names the fields properly", function() {
            let event = new LoggingEvent("foo", log4js.levels.INFO, ["test"]);
            let result = JSON.parse(layout(event));

            expect(result).to.have.property("category", "foo");
            expect(result).to.have.property("level", "INFO");
            expect(result).to.have.property("time");
            expect(result).to.have.property("msg", "test");
        });

        it("handles arrays", function() {
            let event = new LoggingEvent("foo", log4js.levels.INFO, [["123", "456"]]);
            let result = JSON.parse(layout(event));

            expect(result).to.have.property("category", "foo");
            expect(result).to.have.property("level", "INFO");
            expect(result).to.have.property("time");
            expect(result).to.have.property("msg", "[ '123', '456' ]");
        });

        it("handles objects", function() {
            let event = new LoggingEvent("foo", log4js.levels.INFO, [{a: "a", b: "b"}]);
            let result = JSON.parse(layout(event));

            expect(result).to.have.property("category", "foo");
            expect(result).to.have.property("level", "INFO");
            expect(result).to.have.property("time");
            expect(result).to.have.property("msg", "{ a: 'a', b: 'b' }");
        });

        it("handles Error objects", function() {
            let event = new LoggingEvent("foo", log4js.levels.INFO, [new Error("test")]);
            let result = JSON.parse(layout(event));

            expect(result).to.have.property("msg");
            expect(result.msg).to.include("Error: test\n    at");
        });

        it("can concatenate string arguments", function() {
            let event = new LoggingEvent("foo", log4js.levels.INFO, ["test", "123"]);
            let result = JSON.parse(layout(event));

            expect(result).to.have.property("category", "foo");
            expect(result).to.have.property("level", "INFO");
            expect(result).to.have.property("time");
            expect(result).to.have.property("msg", "test 123");
        });

        it("can concatenate mixed arguments", function() {
            let event = new LoggingEvent("foo", log4js.levels.INFO, ["data is", {a: "a", b: "b"}]);
            let result = JSON.parse(layout(event));

            expect(result).to.have.property("category", "foo");
            expect(result).to.have.property("level", "INFO");
            expect(result).to.have.property("time");
            expect(result).to.have.property("msg", "data is { a: 'a', b: 'b' }");
        });

        it("omits undefined fields", function() {
            let event = new LoggingEvent("foo", log4js.levels.INFO, []);
            let result = JSON.parse(layout(event));

            expect(result).to.have.property("category", "foo");
            expect(result).to.have.property("level", "INFO");
            expect(result).not.to.have.property("msg");
        });

        it("emits the fields in order", function() {
            let event = new LoggingEvent("foo", log4js.levels.INFO, ["message"]);
            let result = JSON.parse(layout(event));

            expect(Object.keys(result)).to.deep.equal(["time", "level", "category", "msg"]);
        });
    });

    describe("Correlation IDs", function() {
        let correlationId = require("correlation-id");

        it("can be added to the logs", function() {
            let layout = layouts.layout("json");
            let event = new LoggingEvent("foo", log4js.levels.INFO, ["message"]);

            let result = correlationId.withId("abc123", () => JSON.parse(layout(event)));

            expect(result).to.have.property("correlation-id", "abc123");
        });

        it("are added to requests", function() {
            let http = require("http");

            let request = correlationId.withId("header321", () => {
                return http.get("http://localhost:3000", {
                    headers: { foo: "bar" }, lookup: () => {}
                });
            });

            let header = request.getHeader("x-correlation-id");
            expect(header).to.equal("header321");
        });
    });
});