Move utility package 'namesgenerator' to pkg/namesgenerator

namesgenerator/names-generator.go

@@ -0,0 +1,67 @@
+package namesgenerator
+
+import (
+	"fmt"
+	"math/rand"
+	"time"
+)
+
+type NameChecker interface {
+	Exists(name string) bool
+}
+
+var (
+	left = [...]string{"happy", "jolly", "dreamy", "sad", "angry", "pensive", "focused", "sleepy", "grave", "distracted", "determined", "stoic", "stupefied", "sharp", "agitated", "cocky", "tender", "goofy", "furious", "desperate", "hopeful", "compassionate", "silly", "lonely", "condescending", "naughty", "kickass", "drunk", "boring", "nostalgic", "ecstatic", "insane", "cranky", "mad", "jovial", "sick", "hungry", "thirsty", "elegant", "backstabbing", "clever", "trusting", "loving", "suspicious", "berserk", "high", "romantic", "prickly", "evil"}
+	// Docker 0.7.x generates names from notable scientists and hackers.
+	//
+	// Ada Lovelace invented the first algorithm. http://en.wikipedia.org/wiki/Ada_Lovelace (thanks James Turnbull)
+	// Alan Turing was a founding father of computer science. http://en.wikipedia.org/wiki/Alan_Turing.
+	// Albert Einstein invented the general theory of relativity. http://en.wikipedia.org/wiki/Albert_Einstein
+	// Ambroise Pare invented modern surgery. http://en.wikipedia.org/wiki/Ambroise_Par%C3%A9
+	// Archimedes was a physicist, engineer and mathematician who invented too many things to list them here. http://en.wikipedia.org/wiki/Archimedes
+	// Benjamin Franklin is famous for his experiments in electricity and the invention of the lightning rod.
+	// Charles Babbage invented the concept of a programmable computer. http://en.wikipedia.org/wiki/Charles_Babbage.
+	// Charles Darwin established the principles of natural evolution. http://en.wikipedia.org/wiki/Charles_Darwin.
+	// Dennis Ritchie and Ken Thompson created UNIX and the C programming language. http://en.wikipedia.org/wiki/Dennis_Ritchie http://en.wikipedia.org/wiki/Ken_Thompson
+	// Douglas Engelbart gave the mother of all demos: http://en.wikipedia.org/wiki/Douglas_Engelbart
+	// Emmett Brown invented time travel. http://en.wikipedia.org/wiki/Emmett_Brown (thanks Brian Goff)
+	// Enrico Fermi invented the first nuclear reactor. http://en.wikipedia.org/wiki/Enrico_Fermi.
+	// Euclid invented geometry. http://en.wikipedia.org/wiki/Euclid
+	// Galileo was a founding father of modern astronomy, and faced politics and obscurantism to establish scientific truth.  http://en.wikipedia.org/wiki/Galileo_Galilei
+	// Henry Poincare made fundamental contributions in several fields of mathematics. http://en.wikipedia.org/wiki/Henri_Poincar%C3%A9
+	// Isaac Newton invented classic mechanics and modern optics. http://en.wikipedia.org/wiki/Isaac_Newton
+	// John McCarthy invented LISP: http://en.wikipedia.org/wiki/John_McCarthy_(computer_scientist)
+	// Leonardo Da Vinci invented too many things to list here. http://en.wikipedia.org/wiki/Leonardo_da_Vinci.
+	// Linus Torvalds invented Linux and Git. http://en.wikipedia.org/wiki/Linus_Torvalds
+	// Louis Pasteur discovered vaccination, fermentation and pasteurization. http://en.wikipedia.org/wiki/Louis_Pasteur.
+	// Malcolm McLean invented the modern shipping container: http://en.wikipedia.org/wiki/Malcom_McLean
+	// Marie Curie discovered radioactivity. http://en.wikipedia.org/wiki/Marie_Curie.
+	// Muhammad ibn Jābir al-Ḥarrānī al-Battānī was a founding father of astronomy. http://en.wikipedia.org/wiki/Mu%E1%B8%A5ammad_ibn_J%C4%81bir_al-%E1%B8%A4arr%C4%81n%C4%AB_al-Batt%C4%81n%C4%AB
+	// Niels Bohr is the father of quantum theory. http://en.wikipedia.org/wiki/Niels_Bohr.
+	// Nikola Tesla invented the AC electric system and every gaget ever used by a James Bond villain. http://en.wikipedia.org/wiki/Nikola_Tesla
+	// Pierre de Fermat pioneered several aspects of modern mathematics. http://en.wikipedia.org/wiki/Pierre_de_Fermat
+	// Richard Feynmann was a key contributor to quantum mechanics and particle physics. http://en.wikipedia.org/wiki/Richard_Feynman
+	// Rob Pike was a key contributor to Unix, Plan 9, the X graphic system, utf-8, and the Go programming language. http://en.wikipedia.org/wiki/Rob_Pike
+	// Stephen Hawking pioneered the field of cosmology by combining general relativity and quantum mechanics. http://en.wikipedia.org/wiki/Stephen_Hawking
+	// Steve Wozniak invented the Apple I and Apple II. http://en.wikipedia.org/wiki/Steve_Wozniak
+	// Werner Heisenberg was a founding father of quantum mechanics. http://en.wikipedia.org/wiki/Werner_Heisenberg
+	// William Shockley, Walter Houser Brattain and John Bardeen co-invented the transistor (thanks Brian Goff).
+	//	http://en.wikipedia.org/wiki/John_Bardeen
+	//	http://en.wikipedia.org/wiki/Walter_Houser_Brattain
+	//	http://en.wikipedia.org/wiki/William_Shockley
+	right = [...]string{"lovelace", "franklin", "tesla", "einstein", "bohr", "davinci", "pasteur", "nobel", "curie", "darwin", "turing", "ritchie", "torvalds", "pike", "thompson", "wozniak", "galileo", "euclide", "newton", "fermat", "archimede", "poincare", "heisenberg", "feynmann", "hawkings", "fermi", "pare", "mccarthy", "engelbart", "babbage", "albattani", "ptolemy", "bell", "wright", "lumiere", "morse", "mclean", "brown", "bardeen", "brattain", "shockley"}
+)
+
+func GenerateRandomName(checker NameChecker) (string, error) {
+	retry := 5
+	rand.Seed(time.Now().UnixNano())
+	name := fmt.Sprintf("%s_%s", left[rand.Intn(len(left))], right[rand.Intn(len(right))])
+	for checker != nil && checker.Exists(name) && retry > 0 {
+		name = fmt.Sprintf("%s%d", name, rand.Intn(10))
+		retry = retry - 1
+	}
+	if retry == 0 {
+		return name, fmt.Errorf("Error generating random name")
+	}
+	return name, nil
+}

namesgenerator/names-generator_test.go

@@ -0,0 +1,49 @@
+package namesgenerator
+
+import (
+	"testing"
+)
+
+type FalseChecker struct{}
+
+func (n *FalseChecker) Exists(name string) bool {
+	return false
+}
+
+type TrueChecker struct{}
+
+func (n *TrueChecker) Exists(name string) bool {
+	return true
+}
+
+func TestGenerateRandomName(t *testing.T) {
+	if _, err := GenerateRandomName(&FalseChecker{}); err != nil {
+		t.Error(err)
+	}
+
+	if _, err := GenerateRandomName(&TrueChecker{}); err == nil {
+		t.Error("An error was expected")
+	}
+
+}
+
+// Make sure the generated names are awesome
+func TestGenerateAwesomeNames(t *testing.T) {
+	name, err := GenerateRandomName(&FalseChecker{})
+	if err != nil {
+		t.Error(err)
+	}
+	if !isAwesome(name) {
+		t.Fatalf("Generated name '%s' is not awesome.", name)
+	}
+}
+
+// To be awesome, a container name must involve cool inventors, be easy to remember,
+// be at least mildly funny, and always be politically correct for enterprise adoption.
+func isAwesome(name string) bool {
+	coolInventorNames := true
+	easyToRemember := true
+	mildlyFunnyOnOccasion := true
+	politicallyCorrect := true
+	return coolInventorNames && easyToRemember && mildlyFunnyOnOccasion && politicallyCorrect
+}