diff --git a/pkg/api/generate.go b/pkg/api/generate.go index a3cf5b2a785..772873f90e4 100644 --- a/pkg/api/generate.go +++ b/pkg/api/generate.go @@ -18,7 +18,8 @@ package api import ( "fmt" - "math/rand" + + utilrand "github.com/GoogleCloudPlatform/kubernetes/pkg/util/rand" ) // NameGenerator generates names for objects. Some backends may have more information @@ -59,16 +60,5 @@ func (simpleNameGenerator) GenerateName(base string) string { if len(base) > maxGeneratedNameLength { base = base[:maxGeneratedNameLength] } - value := randSeq(randomLength) - return fmt.Sprintf("%s%s", base, value) -} - -var letters = []rune("abcdefghijklmnopqrstuvwxyz0123456789") - -func randSeq(n int) string { - b := make([]rune, n) - for i := range b { - b[i] = letters[rand.Intn(len(letters))] - } - return string(b) + return fmt.Sprintf("%s%s", base, utilrand.String(randomLength)) } diff --git a/pkg/serviceaccount/tokens_controller_test.go b/pkg/serviceaccount/tokens_controller_test.go index 5871ba6ec82..2e39eafcd37 100644 --- a/pkg/serviceaccount/tokens_controller_test.go +++ b/pkg/serviceaccount/tokens_controller_test.go @@ -17,13 +17,13 @@ limitations under the License. package serviceaccount import ( - "math/rand" "reflect" "testing" "github.com/GoogleCloudPlatform/kubernetes/pkg/api" "github.com/GoogleCloudPlatform/kubernetes/pkg/client/testclient" "github.com/GoogleCloudPlatform/kubernetes/pkg/runtime" + utilrand "github.com/GoogleCloudPlatform/kubernetes/pkg/util/rand" ) type testGenerator struct { @@ -372,7 +372,7 @@ func TestTokenCreation(t *testing.T) { for k, tc := range testcases { // Re-seed to reset name generation - rand.Seed(1) + utilrand.Seed(1) generator := &testGenerator{Token: "ABC"} diff --git a/pkg/util/rand/rand.go b/pkg/util/rand/rand.go new file mode 100644 index 00000000000..25cd056e88a --- /dev/null +++ b/pkg/util/rand/rand.go @@ -0,0 +1,56 @@ +/* +Copyright 2015 The Kubernetes Authors All rights reserved. + +Licensed under the Apache License, Version 2.0 (the "License"); +you may not use this file except in compliance with the License. +You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software +distributed under the License is distributed on an "AS IS" BASIS, +WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +See the License for the specific language governing permissions and +limitations under the License. +*/ + +// Package rand provides utilities related to randomization. +package rand + +import ( + "math/rand" + "sync" + "time" +) + +var letters = []rune("abcdefghijklmnopqrstuvwxyz0123456789") +var numLetters = len(letters) +var rng = struct { + sync.Mutex + rand *rand.Rand +}{ + rand: rand.New(rand.NewSource(time.Now().UTC().UnixNano())), +} + +// String generates a random alphanumeric string n characters long. This will +// panic if n is less than zero. +func String(n int) string { + if n < 0 { + panic("out-of-bounds value") + } + b := make([]rune, n) + rng.Lock() + defer rng.Unlock() + for i := range b { + b[i] = letters[rng.rand.Intn(numLetters)] + } + return string(b) +} + +// Seed seeds the rng with the provided seed. +func Seed(seed int64) { + rng.Lock() + defer rng.Unlock() + + rng.rand = rand.New(rand.NewSource(seed)) +} diff --git a/pkg/util/rand/rand_test.go b/pkg/util/rand/rand_test.go new file mode 100644 index 00000000000..0c76885674e --- /dev/null +++ b/pkg/util/rand/rand_test.go @@ -0,0 +1,37 @@ +/* +Copyright 2015 The Kubernetes Authors All rights reserved. + +Licensed under the Apache License, Version 2.0 (the "License"); +you may not use this file except in compliance with the License. +You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software +distributed under the License is distributed on an "AS IS" BASIS, +WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +See the License for the specific language governing permissions and +limitations under the License. +*/ + +package rand + +import ( + "strings" + "testing" +) + +func TestString(t *testing.T) { + valid := "0123456789abcdefghijklmnopqrstuvwxyz" + for _, l := range []int{0, 1, 2, 10, 123} { + s := String(l) + if len(s) != l { + t.Errorf("expected string of size %d, got %q", l, s) + } + for _, c := range s { + if !strings.ContainsRune(valid, c) { + t.Errorf("expected valid charaters, got %v", c) + } + } + } +}