errors: use cpuguy83/strongerrors

Signed-off-by: Paulo Pires <pjpires@gmail.com>

errors/errors.go

@@ -0,0 +1,49 @@
+// Copyright © 2017 The virtual-kubelet authors
+//
+// 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 errors
+
+import (
+	"fmt"
+	"github.com/cpuguy83/strongerrors"
+)
+
+// DeadlineWithMessage creates a "Deadline" error with the specified message and formatting arguments.
+func DeadlineWithMessage(format string, args ...interface{}) error {
+	return strongerrors.Deadline(fmt.Errorf(format, args...))
+}
+
+// Exhausted creates an "Exhausted" error from the specified error.
+func Exhausted(err error) error {
+	return strongerrors.Exhausted(err)
+}
+
+// InvalidArgument creates an "InvalidArgument" error from the specified error.
+func InvalidArgument(err error) error {
+	return strongerrors.InvalidArgument(err)
+}
+
+// InvalidArgumentWithMessage creates an "InvalidArgument" error with the specified message and formatting arguments.
+func InvalidArgumentWithMessage(format string, args ...interface{}) error {
+	return strongerrors.InvalidArgument(fmt.Errorf(format, args...))
+}
+
+// Unknown creates an "Unknown" error from the specified error and optional message and formatting arguments.
+func Unknown(err error, args ...interface{}) error {
+	// If we've been given additional arguments, re-format the error
+	if len(args) >= 1 {
+		err = fmt.Errorf("%s: %s", fmt.Sprintf(args[0].(string), args[1:]...), err)
+	}
+	return strongerrors.Unknown(err)
+}

errors/errors_test.go

@@ -0,0 +1,73 @@
+// Copyright © 2017 The virtual-kubelet authors
+//
+// 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 errors
+
+import (
+	goerrors "errors"
+	"testing"
+
+	"github.com/cpuguy83/strongerrors"
+)
+
+func TestUnknownFromRoot(t *testing.T) {
+	// Create a root cause.
+	// This represents an error returned by a function invocation.
+	err1 := goerrors.New("root cause")
+	// Create an error of type "Unknown" with err1 as the cause and containing an additional message.
+	err2 := Unknown(err1)
+
+	// Make sure that the resulting error is indeed of type "Unknown".
+	if !strongerrors.IsUnknown(err2) {
+		t.Fatal("expected err2 to be of type Unknown")
+	}
+	// Make sure that the error's message is equal to the root cause's message.
+	if err2.Error() != "root cause" {
+		t.Fatal("expected err2's error message to be equal to the root cause's message")
+	}
+}
+
+func TestUnknownFromRootCauseWithMessage(t *testing.T) {
+	// Create a root cause.
+	// This represents an error returned by a function invocation.
+	err1 := goerrors.New("root cause")
+	// Create an error of type "Unknown" with err1 as the cause and containing an additional message.
+	err2 := Unknown(err1, "extra info")
+
+	// Make sure that the resulting error is indeed of type "Unknown".
+	if !strongerrors.IsUnknown(err2) {
+		t.Fatal("expected err2 to be of type Unknown")
+	}
+	// Make sure that the message was adequately formatted.
+	if err2.Error() != "extra info: root cause" {
+		t.Fatal("expected err2 to be adequately formatted as a string")
+	}
+}
+
+func TestUnknownFromRootCauseWithMessageAndFormattingParameters(t *testing.T) {
+	// Create a root cause.
+	// This represents an error returned by a function invocation.
+	err1 := goerrors.New("root cause")
+	// Create an error of type "Unknown" with err1 as the cause and containing an additional message.
+	err2 := Unknown(err1, "expected %d, got %d", 0, 1)
+
+	// Make sure that the resulting error is indeed of type "Unknown".
+	if !strongerrors.IsUnknown(err2) {
+		t.Fatal("expected err2 to be of type Unknown")
+	}
+	// Make sure that the message was adequately formatted.
+	if err2.Error() != "expected 0, got 1: root cause" {
+		t.Fatal("expected err2 to be adequately formatted as a string")
+	}
+}