Merge pull request #101 from asteris-llc/feature/shell-module

Port shell resource and tests

helpers/fakerenderer/fakerenderer.go

@@ -0,0 +1,26 @@
+// Copyright © 2016 Asteris, LLC
+//
+// 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 fakerenderer
+
+type FakeRenderer struct {
+}
+
+func (fr *FakeRenderer) Value() (string, bool) {
+	return "", true
+}
+
+func (fr *FakeRenderer) Render(name, content string) (string, error) {
+	return content, nil
+}

helpers/fakerenderer/fakerenderer_test.go

@@ -0,0 +1,29 @@
+// Copyright © 2016 Asteris, LLC
+//
+// 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 fakerenderer_test
+
+import (
+	"testing"
+
+	"github.com/asteris-llc/converge/helpers/fakerenderer"
+	"github.com/asteris-llc/converge/resource"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestFakeRendererInterface(t *testing.T) {
+	t.Parallel()
+
+	assert.Implements(t, (*resource.Renderer)(nil), new(fakerenderer.FakeRenderer))
+}

resource/shell/preparer.go

@@ -14,7 +14,11 @@
 
 package shell
 
-import "github.com/asteris-llc/converge/resource"
+import (
+	"os/exec"
+
+	"github.com/asteris-llc/converge/resource"
+)
 
 // Preparer for Shell tasks
 type Preparer struct {
@@ -23,6 +27,51 @@ type Preparer struct {
 }
 
 // Prepare a new task
-func (p *Preparer) Prepare(resource.Renderer) (resource.Task, error) {
-	return &Shell{}, nil
+func (p *Preparer) Prepare(render resource.Renderer) (resource.Task, error) {
+	check, err := render.Render("check", p.Check)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := p.validateScriptSyntax(check); err != nil {
+		return nil, err
+	}
+
+	apply, err := render.Render("apply", p.Apply)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := p.validateScriptSyntax(apply); err != nil {
+		return nil, err
+	}
+
+	return &Shell{check, apply}, nil
+}
+
+func (p *Preparer) validateScriptSyntax(script string) error {
+	command := exec.Command("sh", "-n")
+
+	in, err := command.StdinPipe()
+	if err != nil {
+		return err
+	}
+
+	if err := command.Start(); err != nil {
+		return err
+	}
+
+	if _, err := in.Write([]byte(script)); err != nil {
+		return err
+	}
+
+	if err := in.Close(); err != nil {
+		return err
+	}
+
+	if err := command.Wait(); err != nil {
+		return err
+	}
+
+	return nil
 }

resource/shell/preparer_test.go

@@ -17,6 +17,7 @@ package shell_test
 import (
 	"testing"
 
+	"github.com/asteris-llc/converge/helpers/fakerenderer"
 	"github.com/asteris-llc/converge/resource"
 	"github.com/asteris-llc/converge/resource/shell"
 	"github.com/stretchr/testify/assert"
@@ -27,3 +28,44 @@ func TestPreparerInterface(t *testing.T) {
 
 	assert.Implements(t, (*resource.Resource)(nil), new(shell.Preparer))
 }
+
+func TestPreparerValidateValid(t *testing.T) {
+	t.Parallel()
+
+	sp := &shell.Preparer{
+		Check: "echo test",
+		Apply: "echo test",
+	}
+
+	_, err := sp.Prepare(&fakerenderer.FakeRenderer{})
+
+	assert.NoError(t, err)
+}
+
+func TestPreparerValidateInvalidCheck(t *testing.T) {
+	t.Parallel()
+
+	sp := &shell.Preparer{
+		Check: "if do then; esac",
+	}
+
+	_, err := sp.Prepare(&fakerenderer.FakeRenderer{})
+
+	if assert.Error(t, err) {
+		assert.EqualError(t, err, "exit status 2")
+	}
+}
+
+func TestPreparerValidateInvalidApply(t *testing.T) {
+	t.Parallel()
+
+	sp := &shell.Preparer{
+		Apply: "if do then; esac",
+	}
+
+	_, err := sp.Prepare(&fakerenderer.FakeRenderer{})
+
+	if assert.Error(t, err) {
+		assert.EqualError(t, err, "exit status 2")
+	}
+}

resource/shell/shell.go

@@ -14,16 +14,67 @@
 
 package shell
 
+import (
+	"bytes"
+	"fmt"
+	"os/exec"
+	"syscall"
+)
+
 // Shell task
 type Shell struct {
-	CheckStmt string `prepare:"Check"`
-	ApplyStmt string `prepare:"Apply"`
+	CheckStmt string
+	ApplyStmt string
 }
 
 func (s *Shell) Check() (status string, willChange bool, err error) {
-	return
+	out, code, err := s.exec(s.CheckStmt)
+	return out, code != 0, err
 }
 
 func (s *Shell) Apply() (err error) {
-	return
+	out, code, err := s.exec(s.ApplyStmt)
+	if code != 0 {
+		return fmt.Errorf("exit code %d, output: %q", code, out)
+	}
+	return err
+}
+
+func (s *Shell) exec(script string) (out string, code uint32, err error) {
+	command := exec.Command("sh")
+	stdin, err := command.StdinPipe()
+	if err != nil {
+		return "", 0, err
+	}
+
+	// TODO: does this create a race condition?
+	var sink bytes.Buffer
+	command.Stdout = &sink
+	command.Stderr = &sink
+
+	if err := command.Start(); err != nil {
+		return "", 0, err
+	}
+
+	if _, err := stdin.Write([]byte(script)); err != nil {
+		return "", 0, err
+	}
+
+	if err := stdin.Close(); err != nil {
+		return "", 0, err
+	}
+
+	err = command.Wait()
+	if _, ok := err.(*exec.ExitError); !ok && err != nil {
+		return "", 0, err
+	}
+
+	switch result := command.ProcessState.Sys().(type) {
+	case syscall.WaitStatus:
+		code = uint32(result)
+	default:
+		panic(fmt.Sprintf("unknown type %+v", result))
+	}
+
+	return sink.String(), code, nil
 }

resource/shell/shell_test.go

@@ -0,0 +1,82 @@
+// Copyright © 2016 Asteris, LLC
+//
+// 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 shell_test
+
+import (
+	"testing"
+
+	"github.com/asteris-llc/converge/resource"
+	"github.com/asteris-llc/converge/resource/shell"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestShellInterface(t *testing.T) {
+	t.Parallel()
+
+	assert.Implements(t, (*resource.Task)(nil), new(shell.Shell))
+}
+
+func TestShellTaskCheckNeedsChange(t *testing.T) {
+	t.Parallel()
+
+	s := shell.Shell{
+		CheckStmt: "echo test && exit 1",
+	}
+
+	current, change, err := s.Check()
+	assert.Equal(t, "test\n", current)
+	assert.True(t, change)
+	assert.Nil(t, err)
+}
+
+func TestShellCheckNoChange(t *testing.T) {
+	t.Parallel()
+
+	s := shell.Shell{
+		CheckStmt: "echo test",
+	}
+
+	current, change, err := s.Check()
+	assert.Equal(t, "test\n", current)
+	assert.False(t, change)
+	assert.Nil(t, err)
+}
+
+func TestShellApplySuccess(t *testing.T) {
+	t.Parallel()
+
+	s := shell.Shell{
+		ApplyStmt: "echo test",
+	}
+
+	assert.NoError(t, s.Apply())
+}
+
+func TestShellTaskApplyError(t *testing.T) {
+	t.Parallel()
+
+	s := shell.Shell{
+		ApplyStmt: "echo bad && exit 1",
+	}
+
+	err := s.Apply()
+	if assert.Error(t, err) {
+		assert.EqualError(
+			t,
+			err,
+			`exit code 256, output: "bad\n"`,
+		)
+	}
+}