Merge pull request #40 from inteon/exit_code_bugfix

BUGFIX: return correct error codes and add tests

internal/util/exit_test.go

@@ -0,0 +1,56 @@
+/*
+Copyright 2020 The cert-manager 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 util
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"testing"
+)
+
+func TestSetExitCode(t *testing.T) {
+	tests := []struct {
+		name    string
+		err     error
+		expCode int
+	}{
+		{"Test context.Canceled", context.Canceled, 0},
+		{"Test wrapped context.Canceled", fmt.Errorf("wrapped: %w", context.Canceled), 0},
+		{"Test context.DeadlineExceeded", context.DeadlineExceeded, 124},
+		{"Test wrapped context.DeadlineExceeded", fmt.Errorf("wrapped: %w", context.DeadlineExceeded), 124},
+		{"Test error", errors.New("error"), 1},
+		{"Test nil", nil, 0},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// Every testExitCode call has to be run in its own test, because
+			// it calls the test again filtered by the name of the subtest with
+			// the variable BE_CRASHER=1.
+			exitCode := testExitCode(t, func(t *testing.T) {
+				SetExitCode(tt.err)
+
+				_, complete := SetupExitHandler(context.Background(), AlwaysErrCode)
+				complete()
+			})
+
+			if exitCode != tt.expCode {
+				t.Errorf("Test %s: expected exit code %d, got %d", tt.name, tt.expCode, exitCode)
+			}
+		})
+	}
+}

internal/util/signal.go

@@ -59,7 +59,7 @@ func SetupExitHandler(parentCtx context.Context, exitBehavior ExitBehavior) (con
 		// first signal. Cancel context and pass exit code to errorExitCodeChannel.
 		signalInt := int((<-c).(syscall.Signal))
 		if exitBehavior == AlwaysErrCode {
-			errorExitCodeChannel <- signalInt
+			errorExitCodeChannel <- (128 + signalInt)
 		}
 		cancel(fmt.Errorf("received signal %d", signalInt))
 		// second signal. Exit directly.
@@ -70,7 +70,7 @@ func SetupExitHandler(parentCtx context.Context, exitBehavior ExitBehavior) (con
 	return ctx, func() {
 		select {
 		case signalInt := <-errorExitCodeChannel:
-			os.Exit(128 + signalInt)
+			os.Exit(signalInt)
 		default:
 			// Do not exit, there are no exit codes in the channel,
 			// so just continue and let the main function go out of

internal/util/signal_test.go

@@ -0,0 +1,126 @@
+//go:build !windows
+
+/*
+Copyright 2020 The cert-manager 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 util
+
+import (
+	"context"
+	"os"
+	"os/exec"
+	"syscall"
+	"testing"
+)
+
+// based on https://go.dev/talks/2014/testing.slide#23 and
+// https://stackoverflow.com/a/33404435
+func testExitCode(
+	t *testing.T,
+	fn func(t *testing.T),
+) int {
+	if os.Getenv("BE_CRASHER") == "1" {
+		fn(t)
+		os.Exit(0)
+	}
+
+	cmd := exec.Command(os.Args[0], "-test.run="+t.Name())
+	cmd.Env = append(os.Environ(), "BE_CRASHER=1")
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	err := cmd.Run()
+
+	if e, ok := err.(*exec.ExitError); ok {
+		return e.ExitCode()
+	}
+
+	return 0
+}
+
+func TestSetupExitHandlerAlwaysErrCodeSIGTERM(t *testing.T) {
+	exitCode := testExitCode(t, func(t *testing.T) {
+		ctx := context.Background()
+		ctx, complete := SetupExitHandler(ctx, AlwaysErrCode)
+		defer complete()
+
+		if err := syscall.Kill(syscall.Getpid(), syscall.SIGTERM); err != nil {
+			t.Fatal(err)
+			os.Exit(99)
+		}
+
+		// Wait for the program to shut down.
+		<-ctx.Done()
+
+		if context.Cause(ctx).Error() != "received signal 15" {
+			t.Errorf("expected signal 15, got %s", ctx.Err().Error())
+			os.Exit(99)
+		}
+	})
+
+	if exitCode != 143 {
+		t.Errorf("expected exit code 143, got %d", exitCode)
+	}
+}
+
+func TestSetupExitHandlerAlwaysErrCodeSIGINT(t *testing.T) {
+	exitCode := testExitCode(t, func(t *testing.T) {
+		ctx := context.Background()
+		ctx, complete := SetupExitHandler(ctx, AlwaysErrCode)
+		defer complete()
+
+		if err := syscall.Kill(syscall.Getpid(), syscall.SIGINT); err != nil {
+			t.Fatal(err)
+			os.Exit(99)
+		}
+
+		// Wait for the program to shut down.
+		<-ctx.Done()
+
+		if context.Cause(ctx).Error() != "received signal 2" {
+			t.Errorf("expected signal 2, got %s", ctx.Err().Error())
+			os.Exit(99)
+		}
+	})
+
+	if exitCode != 130 {
+		t.Errorf("expected exit code 130, got %d", exitCode)
+	}
+}
+
+func TestSetupExitHandlerGracefulShutdownSIGINT(t *testing.T) {
+	exitCode := testExitCode(t, func(t *testing.T) {
+		ctx := context.Background()
+		ctx, complete := SetupExitHandler(ctx, GracefulShutdown)
+		defer complete()
+
+		if err := syscall.Kill(syscall.Getpid(), syscall.SIGINT); err != nil {
+			t.Fatal(err)
+			os.Exit(99)
+		}
+
+		// Wait for the program to shut down.
+		<-ctx.Done()
+
+		if context.Cause(ctx).Error() != "received signal 2" {
+			t.Errorf("expected signal 2, got %s", ctx.Err().Error())
+			os.Exit(99)
+		}
+	})
+
+	if exitCode != 0 {
+		t.Errorf("expected exit code 0, got %d", exitCode)
+	}
+}