Add change directory step (#515)

Summary:

Add a cd step that allowers users to change the working directory for all subsequent steps.

Reviewed By: inesusvet

Differential Revision: D63702296

example-ttps/actions/change-directory/basic.yaml

@@ -0,0 +1,23 @@
+---
+api_version: 2.0
+uuid: 236f8a86-8034-43aa-a6e5-979337c375a4
+name: change_directory_example
+description: |
+  This TTP shows you how to use the change_directory action type
+  to change the working directory for all future actions.  If you specify cleanup
+  as default, the directory will be reverted during the cleanup phase.  This may
+  be useful if any of your cleanups make assumptions about their working directory.
+args:
+  - name: cd_destination
+    description: this argument is where we will try to cd to
+    default: /tmp
+steps:
+  - name: "Initial directory"
+    inline: |
+      echo "Current working directory is: \"$(pwd)\""
+  - name: "cd"
+    cd: {{.Args.cd_destination}}
+    cleanup: default
+  - name: "New directory"
+    inline: |
+      echo "Current working directory is: \"$(pwd)\""

pkg/blocks/changedirectory.go

@@ -0,0 +1,117 @@
+/*
+Copyright © 2024-present, Meta Platforms, Inc. and affiliates
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+package blocks
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/facebookincubator/ttpforge/pkg/logging"
+	"github.com/spf13/afero"
+)
+
+// ChangeDirectoryStep is a step that changes the current working directory
+type ChangeDirectoryStep struct {
+	actionDefaults `yaml:",inline"`
+	Cd             string `yaml:"cd"`
+	PreviousDir    string
+	PreviousCDStep *ChangeDirectoryStep
+	FileSystem     afero.Fs `yaml:"-,omitempty"`
+}
+
+// NewChangeDirectoryStep creates a new ChangeDirectoryStep instance with an initialized Act struct.
+func NewChangeDirectoryStep() *ChangeDirectoryStep {
+	return &ChangeDirectoryStep{}
+}
+
+// IsNil checks if a ChangeDirectoryStep is considered empty or unitializied
+func (step *ChangeDirectoryStep) IsNil() bool {
+	return step.Cd == ""
+}
+
+// Validate validates the ChangeDirectoryStep, checking for the necessary attributes and dependencies.
+//
+// **Returns:**
+//
+// error: error if validation fails, nil otherwise
+func (step *ChangeDirectoryStep) Validate(_ TTPExecutionContext) error {
+	// If this has a parent cd step, hold off on validation until execute
+	if step.PreviousCDStep != nil {
+		return nil
+	}
+
+	// Check if cd is provided
+	if step.Cd == "" {
+		err := errors.New("cd must be provided")
+		return err
+	}
+
+	// Check if cd is a valid directory
+	fsys := step.FileSystem
+	if fsys == nil {
+		fsys = afero.NewOsFs()
+	}
+
+	exists, err := afero.DirExists(fsys, step.Cd)
+	if err != nil {
+		return err
+	}
+
+	if !exists {
+		return fmt.Errorf("directory \"%s\" does not exist", step.Cd)
+	}
+
+	return nil
+}
+
+// Execute runs the ChangeDirectoryStep, changing the current working directory and returns an error if any occur.
+//
+// **Returns:**
+//
+// ActResult: the result of the action
+// error: error if execution fails, nil otherwise
+func (step *ChangeDirectoryStep) Execute(ctx TTPExecutionContext) (*ActResult, error) {
+	// If this has a parent, then it's a cleanup step, so we need to grab the previous dir from it
+	if step.PreviousCDStep != nil {
+		if step.PreviousCDStep.PreviousDir == "" {
+			return nil, fmt.Errorf("no previous directory found in parent cd step")
+		}
+		step.Cd = step.PreviousCDStep.PreviousDir
+	}
+
+	logging.L().Infof("Changing directory to %s", step.Cd)
+
+	if step.Cd == "" {
+		return nil, fmt.Errorf("empty cd value in Execute(...)")
+	}
+
+	// Set workdir to the current cd value and store the previous workdir
+	step.PreviousDir = ctx.Vars.WorkDir
+	ctx.Vars.WorkDir = step.Cd
+
+	return &ActResult{}, nil
+}
+
+// GetDefaultCleanupAction sets the directory back to the previous directory
+func (step *ChangeDirectoryStep) GetDefaultCleanupAction() Action {
+	return &ChangeDirectoryStep{
+		PreviousCDStep: step,
+	}
+}

pkg/blocks/changedirectory_test.go

@@ -0,0 +1,121 @@
+/*
+Copyright © 2023-present, Meta Platforms, Inc. and affiliates
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+package blocks
+
+import (
+	"testing"
+
+	"github.com/facebookincubator/ttpforge/pkg/testutils"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestChangeDirectoryExecute(t *testing.T) {
+
+	testCases := []struct {
+		name          string
+		description   string
+		step          *ChangeDirectoryStep
+		fsysContents  map[string][]byte
+		expectedError bool
+		startingDir   string
+	}{
+		{
+			name:        "Change directory to valid directory",
+			description: "Change directory and expect successful change of workdir",
+			step: &ChangeDirectoryStep{
+				Cd: "/tmp",
+			},
+			fsysContents: map[string][]byte{
+				"/home/testuser/test": []byte("test"),
+				"/tmp/test":           []byte("test"),
+			},
+			expectedError: false,
+			startingDir:   "/home/testuser/",
+		},
+		{
+			name:        "Change directory to invalid directory",
+			description: "Try to change directory to invalid directory and expect error",
+			step: &ChangeDirectoryStep{
+				Cd: "/doesntexist",
+			},
+			fsysContents: map[string][]byte{
+				"/home/testuser/test": []byte("test"),
+				"/tmp/test":           []byte("test"),
+			},
+			expectedError: true,
+			startingDir:   "/home/testuser/",
+		},
+		{
+			name:        "Change directory with no given directory",
+			description: "Try to change directory to no directory and expect error",
+			step: &ChangeDirectoryStep{
+				Cd: "",
+			},
+			fsysContents: map[string][]byte{
+				"/home/testuser/test": []byte("test"),
+				"/tmp/test":           []byte("test"),
+			},
+			expectedError: true,
+			startingDir:   "/home/testuser/",
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			// Prep filesystem
+			fsys, err := testutils.MakeAferoTestFs(tc.fsysContents)
+			require.NoError(t, err)
+			tc.step.FileSystem = fsys
+
+			// validate and check error
+			execCtx := NewTTPExecutionContext()
+			execCtx.Vars.WorkDir = tc.startingDir
+			err = tc.step.Validate(execCtx)
+
+			if tc.expectedError && err != nil {
+				require.Error(t, err)
+				return
+			}
+			require.NoError(t, err)
+
+			// execute and check error
+			_, err = tc.step.Execute(execCtx)
+
+			if tc.expectedError && err != nil {
+				require.Error(t, err)
+				return
+			}
+			require.NoError(t, err)
+
+			// check current working directory
+			assert.Equal(t, tc.step.Cd, execCtx.Vars.WorkDir)
+
+			// cleanup and check error
+			err = tc.step.GetDefaultCleanupAction().Validate(execCtx)
+			require.NoError(t, err)
+			_, err = tc.step.GetDefaultCleanupAction().Execute(execCtx)
+			require.NoError(t, err)
+
+			// expect working directory to be rolled back to starting directory
+			assert.Equal(t, tc.startingDir, execCtx.Vars.WorkDir)
+		})
+	}
+}

pkg/blocks/step.go

@@ -250,6 +250,7 @@ func (s *Step) ParseAction(node *yaml.Node) (Action, error) {
 
 	actionCandidates := []Action{
 		NewBasicStep(),
+		NewChangeDirectoryStep(),
 		NewFileStep(),
 		NewSubTTPStep(),
 		NewEditStep(),