Introduce autofix

cmd/inspect.go

@@ -2,6 +2,7 @@ package cmd
 
 import (
 	"fmt"
+	"io"
 	"os"
 	"path/filepath"
 	"strings"
@@ -27,6 +28,7 @@ func (cli *CLI) inspect(opts Options, args []string) int {
 	}
 
 	issues := tflint.Issues{}
+	changes := map[string][]byte{}
 
 	for _, wd := range workingDirs {
 		err := cli.withinChangedDir(wd, func() error {
@@ -62,11 +64,14 @@ func (cli *CLI) inspect(opts Options, args []string) int {
 			for i, file := range filterFiles {
 				filterFiles[i] = filepath.Join(wd, file)
 			}
-			moduleIssues, err := cli.inspectModule(opts, targetDir, filterFiles)
+			moduleIssues, moduleChanges, err := cli.inspectModule(opts, targetDir, filterFiles)
 			if err != nil {
 				return err
 			}
 			issues = append(issues, moduleIssues...)
+			for path, source := range moduleChanges {
+				changes[path] = source
+			}
 			return nil
 		})
 		if err != nil {
@@ -91,8 +96,33 @@ func (cli *CLI) inspect(opts Options, args []string) int {
 		force = cli.config.Force
 	}
 
+	// TODO: Autofixed issues should contain the previous source code
+	// TODO: Show "fixed" mark in pretty format
 	cli.formatter.Print(issues, nil, cli.sources)
 
+	if opts.Fix {
+		fs := afero.NewOsFs()
+		for path, source := range changes {
+			f, err := fs.OpenFile(path, os.O_WRONLY|os.O_TRUNC, 0644)
+			if err != nil {
+				cli.formatter.Print(tflint.Issues{}, fmt.Errorf("Failed to apply autofix; failed to open %s: %w", path, err), cli.sources)
+				return ExitCodeError
+			}
+
+			n, err := f.Write(source)
+			if err == nil && n < len(source) {
+				err = io.ErrShortWrite
+			}
+			if err1 := f.Close(); err == nil {
+				err = err1
+			}
+			if err != nil {
+				cli.formatter.Print(tflint.Issues{}, fmt.Errorf("Failed to apply autofix; failed to write source code to %s: %w", path, err), cli.sources)
+				return ExitCodeError
+			}
+		}
+	}
+
 	if len(issues) > 0 && !force && exceedsMinimumFailure(issues, opts.MinimumFailureSeverity) {
 		return ExitCodeIssuesFound
 	}
@@ -143,31 +173,32 @@ func processArgs(args []string) (string, []string, error) {
 	return dir, filterFiles, nil
 }
 
-func (cli *CLI) inspectModule(opts Options, dir string, filterFiles []string) (tflint.Issues, error) {
+func (cli *CLI) inspectModule(opts Options, dir string, filterFiles []string) (tflint.Issues, map[string][]byte, error) {
 	issues := tflint.Issues{}
+	changes := map[string][]byte{}
 	var err error
 
 	// Setup config
 	cli.config, err = tflint.LoadConfig(afero.Afero{Fs: afero.NewOsFs()}, opts.Config)
 	if err != nil {
-		return tflint.Issues{}, fmt.Errorf("Failed to load TFLint config; %w", err)
+		return issues, changes, fmt.Errorf("Failed to load TFLint config; %w", err)
 	}
 	cli.config.Merge(opts.toConfig())
 
 	// Setup loader
 	cli.loader, err = terraform.NewLoader(afero.Afero{Fs: afero.NewOsFs()}, cli.originalWorkingDir)
 	if err != nil {
-		return tflint.Issues{}, fmt.Errorf("Failed to prepare loading; %w", err)
+		return issues, changes, fmt.Errorf("Failed to prepare loading; %w", err)
 	}
 	if opts.Recursive && !cli.loader.IsConfigDir(dir) {
 		// Ignore non-module directories in recursive mode
-		return tflint.Issues{}, nil
+		return issues, changes, nil
 	}
 
 	// Setup runners
 	runners, err := cli.setupRunners(opts, dir)
 	if err != nil {
-		return tflint.Issues{}, err
+		return issues, changes, err
 	}
 	rootRunner := runners[len(runners)-1]
 
@@ -177,7 +208,7 @@ func (cli *CLI) inspectModule(opts Options, dir string, filterFiles []string) (t
 		defer rulesetPlugin.Clean()
 	}
 	if err != nil {
-		return tflint.Issues{}, err
+		return issues, changes, err
 	}
 
 	// Run inspection
@@ -186,32 +217,35 @@ func (cli *CLI) inspectModule(opts Options, dir string, filterFiles []string) (t
 		if err != nil {
 			if st, ok := status.FromError(err); ok && st.Code() == codes.Unimplemented {
 				// SDKVersion endpoint is available in tflint-plugin-sdk v0.14+.
-				return tflint.Issues{}, fmt.Errorf(`Plugin "%s" SDK version is incompatible. Compatible versions: %s`, name, plugin.SDKVersionConstraints)
+				return issues, changes, fmt.Errorf(`Plugin "%s" SDK version is incompatible. Compatible versions: %s`, name, plugin.SDKVersionConstraints)
 			} else {
-				return tflint.Issues{}, fmt.Errorf(`Failed to get plugin "%s" SDK version; %w`, name, err)
+				return issues, changes, fmt.Errorf(`Failed to get plugin "%s" SDK version; %w`, name, err)
 			}
 		}
 		if !plugin.SDKVersionConstraints.Check(sdkVersion) {
-			return tflint.Issues{}, fmt.Errorf(`Plugin "%s" SDK version (%s) is incompatible. Compatible versions: %s`, name, sdkVersion, plugin.SDKVersionConstraints)
+			return issues, changes, fmt.Errorf(`Plugin "%s" SDK version (%s) is incompatible. Compatible versions: %s`, name, sdkVersion, plugin.SDKVersionConstraints)
 		}
 
 		for _, runner := range runners {
 			err = ruleset.Check(plugin.NewGRPCServer(runner, rootRunner, cli.loader.Files(), sdkVersion))
 			if err != nil {
-				return tflint.Issues{}, fmt.Errorf("Failed to check ruleset; %w", err)
+				return issues, changes, fmt.Errorf("Failed to check ruleset; %w", err)
 			}
 		}
 	}
 
 	for _, runner := range runners {
 		issues = append(issues, runner.LookupIssues(filterFiles...)...)
+		for path, source := range runner.Changes {
+			changes[path] = source
+		}
 	}
 	// Set module sources to CLI
 	for path, source := range cli.loader.Sources() {
 		cli.sources[path] = source
 	}
 
-	return issues, nil
+	return issues, changes, nil
 }
 
 func (cli *CLI) setupRunners(opts Options, dir string) ([]*tflint.Runner, error) {
@@ -285,6 +319,7 @@ func launchPlugins(config *tflint.Config) (*plugin.Plugin, error) {
 			return rulesetPlugin, fmt.Errorf("Failed to satisfy version constraints; tflint-ruleset-%s requires %s, but TFLint version is %s", name, constraints, tflint.Version)
 		}
 
+		// TODO: Apply fix option to plugins
 		if err := ruleset.ApplyGlobalConfig(pluginConf); err != nil {
 			return rulesetPlugin, fmt.Errorf("Failed to apply global config to `%s` plugin; %w", name, err)
 		}

cmd/option.go

@@ -30,6 +30,7 @@ type Options struct {
 	MinimumFailureSeverity string   `long:"minimum-failure-severity" description:"Sets minimum severity level for exiting with a non-zero error code" choice:"error" choice:"warning" choice:"notice"`
 	Color                  bool     `long:"color" description:"Enable colorized output"`
 	NoColor                bool     `long:"no-color" description:"Disable colorized output"`
+	Fix                    bool     `long:"fix" description:"Fix issues automatically"`
 	ActAsBundledPlugin     bool     `long:"act-as-bundled-plugin" hidden:"true"`
 }
 

go.mod

@@ -24,7 +24,7 @@ require (
 	github.com/sourcegraph/go-lsp v0.0.0-20200429204803-219e11d77f5d
 	github.com/sourcegraph/jsonrpc2 v0.2.0
 	github.com/spf13/afero v1.9.5
-	github.com/terraform-linters/tflint-plugin-sdk v0.16.1
+	github.com/terraform-linters/tflint-plugin-sdk v0.16.2-0.20230502084831-d07f1427f697
 	github.com/terraform-linters/tflint-ruleset-terraform v0.2.2
 	github.com/xeipuuv/gojsonschema v1.2.0
 	github.com/zclconf/go-cty v1.13.1

go.sum

@@ -457,8 +457,8 @@ github.com/stretchr/testify v1.7.2/go.mod h1:R6va5+xMeoiuVRoj+gSkQ7d3FALtqAAGI1F
 github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
 github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
-github.com/terraform-linters/tflint-plugin-sdk v0.16.1 h1:fBfLL8KzP3pkQrNp3iQxaGoKBoMo2sFYoqmhuo6yc+A=
-github.com/terraform-linters/tflint-plugin-sdk v0.16.1/go.mod h1:ltxVy04PRwptL6P/Ugz2ZeTNclYapClrLn/kVFXJGzo=
+github.com/terraform-linters/tflint-plugin-sdk v0.16.2-0.20230502084831-d07f1427f697 h1:9T4wKOqLj6m03SCD/MiazysAYjQH0PCwyWYFOmg5+ps=
+github.com/terraform-linters/tflint-plugin-sdk v0.16.2-0.20230502084831-d07f1427f697/go.mod h1:ltxVy04PRwptL6P/Ugz2ZeTNclYapClrLn/kVFXJGzo=
 github.com/terraform-linters/tflint-ruleset-terraform v0.2.2 h1:iTE09KkaZ0DE29xvp6IIM1/gmas9V0h8CER28SyBmQ8=
 github.com/terraform-linters/tflint-ruleset-terraform v0.2.2/go.mod h1:bCkvH8Vqzr16bWEE3e6Q3hvdZlmSAOR8i6G3M5y+M+k=
 github.com/ulikunitz/xz v0.5.10 h1:t92gobL9l3HE202wg3rlk19F6X+JOxl9BBrCCMYEYd8=

plugin/server.go

@@ -8,6 +8,7 @@ import (
 	"github.com/hashicorp/go-version"
 	hcl "github.com/hashicorp/hcl/v2"
 	"github.com/terraform-linters/tflint-plugin-sdk/hclext"
+	"github.com/terraform-linters/tflint-plugin-sdk/plugin/plugin2host"
 	sdk "github.com/terraform-linters/tflint-plugin-sdk/tflint"
 	"github.com/terraform-linters/tflint/terraform"
 	"github.com/terraform-linters/tflint/tflint"
@@ -22,6 +23,8 @@ type GRPCServer struct {
 	clientSDKVersion *version.Version
 }
 
+var _ plugin2host.Server = (*GRPCServer)(nil)
+
 // NewGRPCServer initializes a gRPC server for plugins.
 func NewGRPCServer(runner *tflint.Runner, rootRunner *tflint.Runner, files map[string]*hcl.File, sdkVersion *version.Version) *GRPCServer {
 	return &GRPCServer{runner: runner, rootRunner: rootRunner, files: files, clientSDKVersion: sdkVersion}
@@ -183,19 +186,32 @@ func (s *GRPCServer) EvaluateExpr(expr hcl.Expression, opts sdk.EvaluateExprOpti
 // If the range associated with the issue is an expression, it propagates to the runner
 // that the issue found in that expression. This allows you to determine if the issue was caused
 // by a module argument in the case of module inspection.
-func (s *GRPCServer) EmitIssue(rule sdk.Rule, message string, location hcl.Range) error {
+func (s *GRPCServer) EmitIssue(rule sdk.Rule, message string, location hcl.Range, fixed map[string][]byte) error {
 	file := s.runner.File(location.Filename)
 	if file == nil {
 		s.runner.EmitIssue(rule, message, location)
 		return nil
 	}
+
 	expr, diags := hclext.ParseExpression(location.SliceBytes(file.Bytes), location.Filename, location.Start)
 	if diags.HasErrors() {
 		s.runner.EmitIssue(rule, message, location)
-		return nil
+	} else {
+		err := s.runner.WithExpressionContext(expr, func() error {
+			s.runner.EmitIssue(rule, message, location)
+			return nil
+		})
+		if err != nil {
+			return err
+		}
 	}
-	return s.runner.WithExpressionContext(expr, func() error {
-		s.runner.EmitIssue(rule, message, location)
+
+	if len(fixed) == 0 {
 		return nil
-	})
+	}
+	diags = s.runner.ApplyChanges(fixed)
+	if diags.HasErrors() {
+		return diags
+	}
+	return nil
 }

plugin/server_test.go

@@ -707,27 +707,27 @@ resource "aws_instance" "foo" {
 
 	tests := []struct {
 		Name string
-		Args func() (sdk.Rule, string, hcl.Range)
+		Args func() (sdk.Rule, string, hcl.Range, map[string][]byte)
 		Want int
 	}{
 		{
 			Name: "on expr",
-			Args: func() (sdk.Rule, string, hcl.Range) {
-				return &testRule{}, "error", exprRange
+			Args: func() (sdk.Rule, string, hcl.Range, map[string][]byte) {
+				return &testRule{}, "error", exprRange, map[string][]byte{}
 			},
 			Want: 1,
 		},
 		{
 			Name: "on non-expr",
-			Args: func() (sdk.Rule, string, hcl.Range) {
-				return &testRule{}, "error", resourceDefRange
+			Args: func() (sdk.Rule, string, hcl.Range, map[string][]byte) {
+				return &testRule{}, "error", resourceDefRange, map[string][]byte{}
 			},
 			Want: 1,
 		},
 		{
 			Name: "on another file",
-			Args: func() (sdk.Rule, string, hcl.Range) {
-				return &testRule{}, "error", hcl.Range{Filename: "not_found.tf"}
+			Args: func() (sdk.Rule, string, hcl.Range, map[string][]byte) {
+				return &testRule{}, "error", hcl.Range{Filename: "not_found.tf"}, map[string][]byte{}
 			},
 			Want: 1,
 		},

terraform/module.go

@@ -5,6 +5,8 @@ import (
 	"strings"
 
 	"github.com/hashicorp/hcl/v2"
+	"github.com/hashicorp/hcl/v2/hclsyntax"
+	hcljson "github.com/hashicorp/hcl/v2/json"
 	"github.com/terraform-linters/tflint-plugin-sdk/hclext"
 )
 
@@ -19,8 +21,8 @@ type Module struct {
 	Sources map[string][]byte
 	Files   map[string]*hcl.File
 
-	primaries []*hcl.File
-	overrides []*hcl.File
+	primaries map[string]*hcl.File
+	overrides map[string]*hcl.File
 }
 
 func NewEmptyModule() *Module {
@@ -35,8 +37,8 @@ func NewEmptyModule() *Module {
 		Sources: map[string][]byte{},
 		Files:   map[string]*hcl.File{},
 
-		primaries: []*hcl.File{},
-		overrides: []*hcl.File{},
+		primaries: map[string]*hcl.File{},
+		overrides: map[string]*hcl.File{},
 	}
 }
 
@@ -73,6 +75,40 @@ func (m *Module) build() hcl.Diagnostics {
 	return diags
 }
 
+func (m *Module) Rebuild(sources map[string][]byte) hcl.Diagnostics {
+	if len(sources) == 0 {
+		return nil
+	}
+	var diags hcl.Diagnostics
+
+	for path, source := range sources {
+		var file *hcl.File
+		var d hcl.Diagnostics
+		if strings.HasSuffix(path, ".json") {
+			file, d = hcljson.Parse(source, path)
+		} else {
+			file, d = hclsyntax.ParseConfig(source, path, hcl.InitialPos)
+		}
+		if d.HasErrors() {
+			diags = diags.Extend(d)
+			continue
+		}
+
+		m.Sources[path] = source
+		m.Files[path] = file
+		if _, exists := m.primaries[path]; exists {
+			m.primaries[path] = file
+		}
+		if _, exists := m.overrides[path]; exists {
+			m.overrides[path] = file
+		}
+	}
+
+	d := m.build()
+	diags = diags.Extend(d)
+	return diags
+}
+
 // PartialContent extracts body content from Terraform configurations based on the passed schema.
 // Basically, this function is a wrapper for hclext.PartialContent, but in some ways it reproduces
 // Terraform language semantics.

terraform/parser.go

@@ -65,30 +65,28 @@ func (p *Parser) LoadConfigDir(baseDir, dir string) (*Module, hcl.Diagnostics) {
 	}
 
 	mod := NewEmptyModule()
-	mod.primaries = make([]*hcl.File, len(primaries))
-	mod.overrides = make([]*hcl.File, len(overrides))
 
-	for i, path := range primaries {
+	for _, path := range primaries {
 		f, loadDiags := p.loadHCLFile(baseDir, path)
 		diags = diags.Extend(loadDiags)
 		if loadDiags.HasErrors() {
 			continue
 		}
 		realPath := filepath.Join(baseDir, path)
 
-		mod.primaries[i] = f
+		mod.primaries[realPath] = f
 		mod.Sources[realPath] = f.Bytes
 		mod.Files[realPath] = f
 	}
-	for i, path := range overrides {
+	for _, path := range overrides {
 		f, loadDiags := p.loadHCLFile(baseDir, path)
 		diags = diags.Extend(loadDiags)
 		if loadDiags.HasErrors() {
 			continue
 		}
 		realPath := filepath.Join(baseDir, path)
 
-		mod.overrides[i] = f
+		mod.overrides[realPath] = f
 		mod.Sources[realPath] = f.Bytes
 		mod.Files[realPath] = f
 	}