Merge branch '189_sign_sequence_generation' into 'master'

189 sign sequence generation

Introduce sequence generation into the platform.

See merge request !36

dfssp/contract/sequence.go

+package contract
+
+import (
+	"dfss/dfssp/entities"
+)
+
+// GenerateSignSequence for the contract signature
+//
+// The generated sequence is an array of integers refering to the User array.
+func GenerateSignSequence(users []*entities.User) []int {
+	return SquaredSignEngine(len(users))
+}
+
+// SquaredSignEngine is a basic ^2 engine for sequence generation
+func SquaredSignEngine(n int) []int {
+	sequence := make([]int, n*n)
+
+	for i := 0; i < n; i++ {
+		for k := 0; k < n; k++ {
+			sequence[i*n+k] = k
+		}
+	}
+
+	return sequence
+}
+
+// SquaredSignEngineSlice is the same as the above with slicing
+func SquaredSignEngineSlice(n int) []int {
+	baseSequence := make([]int, n)
+
+	// populate base slice
+	for i := 0; i < n; i++ {
+		baseSequence[i] = i
+	}
+
+	sequence := make([]int, 0, n*n)
+	// append n-1 time the slice to itself
+	for i := 0; i < n; i++ {
+		sequence = append(sequence, baseSequence...)
+	}
+
+	return sequence
+}

dfssp/contract/sequence_test.go

+package contract_test
+
+import (
+	"dfss/dfssp/contract"
+	"dfss/dfssp/entities"
+	"github.com/bmizerany/assert"
+	"testing"
+)
+
+var refSeq = []int{0, 1, 2, 0, 1, 2, 0, 1, 2} // for n = 3
+
+func TestGenerateSignSequence(t *testing.T) {
+
+	// initialise fixtures
+	var users = make([]*entities.User, 3)
+	users[0] = entities.NewUser()
+	users[1] = entities.NewUser()
+	users[2] = entities.NewUser()
+	users[0].Email = "user1@example.com"
+	users[1].Email = "user2@example.com"
+	users[2].Email = "user3@example.com"
+
+	assert.Equal(t, refSeq, contract.GenerateSignSequence(users))
+}
+
+// Perform sequence generation in a loop
+func BenchmarkSquaredEngine(b *testing.B) {
+
+	for i := 0; i < b.N; i++ {
+		_ = contract.SquaredSignEngine(10)
+	}
+}
+
+// Perform sequence generation in a loop with slicing
+func BenchmarkSquaredEngineSlice(b *testing.B) {
+
+	for i := 0; i < b.N; i++ {
+		_ = contract.SquaredSignEngineSlice(10)
+	}
+}