first commit

internal/command/command.go

@@ -0,0 +1,44 @@
+/*
+© Copyright IBM Corporation 2017, 2022
+
+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 command contains code to run external commands
+package command
+
+import (
+	"context"
+	"fmt"
+	"os/exec"
+)
+
+// Run runs an OS command.  On Linux it waits for the command to
+// complete and returns the exit status (return code).
+// Do not use this function to run shell built-ins (like "cd"), because
+// the error handling works differently
+func Run(name string, arg ...string) (string, int, error) {
+	return RunContext(context.Background(), name, arg...)
+}
+
+func RunContext(ctx context.Context, name string, arg ...string) (string, int, error) {
+	// Run the command and wait for completion
+	// #nosec G204
+	cmd := exec.CommandContext(ctx, name, arg...)
+	out, err := cmd.CombinedOutput()
+	rc := cmd.ProcessState.ExitCode()
+	if err != nil {
+		return string(out), rc, fmt.Errorf("%v: %v", cmd.Path, err)
+	}
+	return string(out), rc, nil
+}

internal/command/command_test.go

@@ -0,0 +1,47 @@
+/*
+© Copyright IBM Corporation 2017
+
+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 command
+
+import (
+	"runtime"
+	"testing"
+)
+
+var commandTests = []struct {
+	name string
+	arg  []string
+	rc   int
+}{
+	{"ls", []string{}, 0},
+	{"ls", []string{"madeup"}, 2},
+	{"bash", []string{"-c", "exit 99"}, 99},
+}
+
+func TestRun(t *testing.T) {
+	if runtime.GOOS != "linux" {
+		t.Skip("Skipping tests for package which only works on Linux")
+	}
+	for _, table := range commandTests {
+		arg := table.arg
+		_, rc, err := Run(table.name, arg...)
+		if rc != table.rc {
+			t.Errorf("Run(%v,%v) - expected %v, got %v", table.name, table.arg, table.rc, rc)
+		}
+		if rc != 0 && err == nil {
+			t.Errorf("Run(%v,%v) - expected error for non-zero return code (rc=%v)", table.name, table.arg, rc)
+		}
+	}
+}