Chris James quii

Learn Go with Tests: Intro to acceptance tests

We've been running into the need to have "graceful shutdown" for our services.

Graceful shutdown is making sure your system finishes its work properly before it is terminated. A real-world analogy would be someone trying to wrap-up a phone call properly before moving on to the next meeting, rather than just hanging-up mid-sentence.

This post will give an intro to graceful shutdown in the context of a HTTP server, and how to write "acceptance tests" to give yourself confidence in the behaviour of your code.

After reading this you'll know how to share packages with excellent tests, reduce maintenance efforts and, increase confidence in the quality of your work.

Refactoring step, starting checklist

Refactoring (or as i often annoyingly call it, "Furniture arranging") is a skill that once practiced enough, becomes second-nature, and in a lot of cases, very easy.

It often gets conflated with design, but they are separate activities.

Refactoring vs Design

Refactoring is just improving existing code and not changing behaviour, and it's usually very localised changes; tests shouldn't have to change. A lot of very helpful refactorings are simple to learn, easy to do (many are almost entirely automated by your IDE) but over time become hugely impactful to the quality of our system.

Words are important

Chris James 15 Jul 2020 https://quii.dev

"Mocking"

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Let's say I have a funds index with 2 documents like this

{
  "fundId": 123,
  "fundManager": {
    "id": 123434,
 "name": "Chris Inc"

	(ns tdd-clojure.contract-test
	(:require [clojure.string :as str]
	[clojure.test :refer :all]))

	(defn test-greet-contract [greet-fn]
	(testing "greet function should return a greeting with the given name"
	(let [name "Chris"]
	(is (= (greet-fn name) (str "Hello, " name))))))

	;; Example implementation of the greet function

	package main

	import "fmt"

	func main() {
	someNumbers := []int64{1, 2, 3}
	someNames := []string{"John", "Chris", "Mary"}

	fmt.Println(Reduce(someNumbers, 0, func(a, b int64) int64 {
	return a + b

	package learn_go_with_tests

	import (
	"fmt"
	"testing"
	)

	func Add(x, y int) int {
	return 3
	}

	package main

	import (
	"fmt"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"
	)

	func Stitcher(w http.ResponseWriter, r *http.Request) {
	urls := r.URL.Query()["url"]

	if len(urls) == 0 {
	http.Error(w, "please provide a url querystring value", http.StatusBadRequest)
	return
	}

	bodies := make(chan io.ReadCloser, len(urls))