Make terraform cloud provider able to parse log including ansi codes (#…

…2189)

**What this PR does / why we need it**:

**Which issue(s) this PR fixes**:

Fixes #674

**Does this PR introduce a user-facing change?**:
<!--
If no, just write "NONE" in the release-note block below.
-->
```release-note
NONE
```

This PR was merged by Kapetanios.

pkg/app/piped/cloudprovider/terraform/terraform.go

@@ -25,19 +25,49 @@ import (
 	"strings"
 )
 
+type options struct {
+	noColor  bool
+	vars     []string
+	varFiles []string
+}
+
+type Option func(*options)
+
+func WithoutColor() Option {
+	return func(opts *options) {
+		opts.noColor = true
+	}
+}
+
+func WithVars(vars []string) Option {
+	return func(opts *options) {
+		opts.vars = vars
+	}
+}
+
+func WithVarFiles(files []string) Option {
+	return func(opts *options) {
+		opts.varFiles = files
+	}
+}
+
 type Terraform struct {
 	execPath string
 	dir      string
-	vars     []string
-	varFiles []string
+
+	options options
 }
 
-func NewTerraform(execPath, dir string, vars, varFiles []string) *Terraform {
+func NewTerraform(execPath, dir string, opts ...Option) *Terraform {
+	opt := options{}
+	for _, o := range opts {
+		o(&opt)
+	}
+
 	return &Terraform{
 		execPath: execPath,
 		dir:      dir,
-		vars:     vars,
-		varFiles: varFiles,
+		options:  opt,
 	}
 }
 
@@ -58,12 +88,7 @@ func (t *Terraform) Init(ctx context.Context, w io.Writer) error {
 	args := []string{
 		"init",
 	}
-	for _, v := range t.vars {
-		args = append(args, fmt.Sprintf("-var=%s", v))
-	}
-	for _, f := range t.varFiles {
-		args = append(args, fmt.Sprintf("-var-file=%s", f))
-	}
+	args = append(args, t.makeCommonCommandArgs()...)
 
 	cmd := exec.CommandContext(ctx, t.execPath, args...)
 	cmd.Dir = t.dir
@@ -114,17 +139,10 @@ func GetExitCode(err error) int {
 func (t *Terraform) Plan(ctx context.Context, w io.Writer) (PlanResult, error) {
 	args := []string{
 		"plan",
-		// TODO: Remove this -no-color flag after parsePlanResult supports parsing the message containing color codes.
-		"-no-color",
 		"-lock=false",
 		"-detailed-exitcode",
 	}
-	for _, v := range t.vars {
-		args = append(args, fmt.Sprintf("-var=%s", v))
-	}
-	for _, f := range t.varFiles {
-		args = append(args, fmt.Sprintf("-var-file=%s", f))
-	}
+	args = append(args, t.makeCommonCommandArgs()...)
 
 	var buf bytes.Buffer
 	stdout := io.MultiWriter(w, &buf)
@@ -140,18 +158,40 @@ func (t *Terraform) Plan(ctx context.Context, w io.Writer) (PlanResult, error) {
 	case 0:
 		return PlanResult{}, nil
 	case 2:
-		return parsePlanResult(buf.String())
+		return parsePlanResult(buf.String(), !t.options.noColor)
 	default:
 		return PlanResult{}, err
 	}
 }
 
+func (t *Terraform) makeCommonCommandArgs() (args []string) {
+	if t.options.noColor {
+		args = append(args, "-no-color")
+	}
+	for _, v := range t.options.vars {
+		args = append(args, fmt.Sprintf("-var=%s", v))
+	}
+	for _, f := range t.options.varFiles {
+		args = append(args, fmt.Sprintf("-var-file=%s", f))
+	}
+	return
+}
+
 var (
 	planHasChangeRegex = regexp.MustCompile(`(?m)^Plan: (\d+) to add, (\d+) to change, (\d+) to destroy.$`)
 	planNoChangesRegex = regexp.MustCompile(`(?m)^No changes. Infrastructure is up-to-date.$`)
 )
 
-func parsePlanResult(out string) (PlanResult, error) {
+// Borrowed from https://github.com/acarl005/stripansi
+const ansi = "[\u001B\u009B][[\\]()#;?]*(?:(?:(?:[a-zA-Z\\d]*(?:;[a-zA-Z\\d]*)*)?\u0007)|(?:(?:\\d{1,4}(?:;\\d{0,4})*)?[\\dA-PRZcf-ntqry=><~]))"
+
+var ansiRegex = regexp.MustCompile(ansi)
+
+func stripAnsiCodes(str string) string {
+	return ansiRegex.ReplaceAllString(str, "")
+}
+
+func parsePlanResult(out string, ansiIncluded bool) (PlanResult, error) {
 	parseNums := func(add, change, destroy string) (adds int, changes int, destroys int, err error) {
 		adds, err = strconv.Atoi(add)
 		if err != nil {
@@ -168,6 +208,10 @@ func parsePlanResult(out string) (PlanResult, error) {
 		return
 	}
 
+	if ansiIncluded {
+		out = stripAnsiCodes(out)
+	}
+
 	if s := planHasChangeRegex.FindStringSubmatch(out); len(s) == 4 {
 		adds, changes, destroys, err := parseNums(s[1], s[2], s[3])
 		if err == nil {
@@ -192,12 +236,7 @@ func (t *Terraform) Apply(ctx context.Context, w io.Writer) error {
 		"-auto-approve",
 		"-input=false",
 	}
-	for _, v := range t.vars {
-		args = append(args, fmt.Sprintf("-var=%s", v))
-	}
-	for _, f := range t.varFiles {
-		args = append(args, fmt.Sprintf("-var-file=%s", f))
-	}
+	args = append(args, t.makeCommonCommandArgs()...)
 
 	cmd := exec.CommandContext(ctx, t.execPath, args...)
 	cmd.Dir = t.dir

pkg/app/piped/executor/terraform/deploy.go

@@ -89,7 +89,12 @@ func (e *deployExecutor) Execute(sig executor.StopSignal) model.StageStatus {
 }
 
 func (e *deployExecutor) ensureSync(ctx context.Context) model.StageStatus {
-	cmd := provider.NewTerraform(e.terraformPath, e.appDir, e.vars, e.deployCfg.Input.VarFiles)
+	cmd := provider.NewTerraform(
+		e.terraformPath,
+		e.appDir,
+		provider.WithVars(e.vars),
+		provider.WithVarFiles(e.deployCfg.Input.VarFiles),
+	)
 
 	if ok := showUsingVersion(ctx, cmd, e.LogPersister); !ok {
 		return model.StageStatus_STAGE_FAILURE
@@ -127,7 +132,12 @@ func (e *deployExecutor) ensureSync(ctx context.Context) model.StageStatus {
 }
 
 func (e *deployExecutor) ensurePlan(ctx context.Context) model.StageStatus {
-	cmd := provider.NewTerraform(e.terraformPath, e.appDir, e.vars, e.deployCfg.Input.VarFiles)
+	cmd := provider.NewTerraform(
+		e.terraformPath,
+		e.appDir,
+		provider.WithVars(e.vars),
+		provider.WithVarFiles(e.deployCfg.Input.VarFiles),
+	)
 
 	if ok := showUsingVersion(ctx, cmd, e.LogPersister); !ok {
 		return model.StageStatus_STAGE_FAILURE
@@ -158,7 +168,12 @@ func (e *deployExecutor) ensurePlan(ctx context.Context) model.StageStatus {
 }
 
 func (e *deployExecutor) ensureApply(ctx context.Context) model.StageStatus {
-	cmd := provider.NewTerraform(e.terraformPath, e.appDir, e.vars, e.deployCfg.Input.VarFiles)
+	cmd := provider.NewTerraform(
+		e.terraformPath,
+		e.appDir,
+		provider.WithVars(e.vars),
+		provider.WithVarFiles(e.deployCfg.Input.VarFiles),
+	)
 
 	if ok := showUsingVersion(ctx, cmd, e.LogPersister); !ok {
 		return model.StageStatus_STAGE_FAILURE

pkg/app/piped/executor/terraform/rollback.go

@@ -79,7 +79,12 @@ func (e *rollbackExecutor) ensureRollback(ctx context.Context) model.StageStatus
 	vars = append(vars, deployCfg.Input.Vars...)
 
 	e.LogPersister.Infof("Start rolling back to the state defined at commit %s", e.Deployment.RunningCommitHash)
-	cmd := provider.NewTerraform(terraformPath, ds.AppDir, vars, deployCfg.Input.VarFiles)
+	cmd := provider.NewTerraform(
+		terraformPath,
+		ds.AppDir,
+		provider.WithVars(vars),
+		provider.WithVarFiles(deployCfg.Input.VarFiles),
+	)
 
 	if ok := showUsingVersion(ctx, cmd, e.LogPersister); !ok {
 		return model.StageStatus_STAGE_FAILURE

pkg/app/piped/planpreview/terraformdiff.go

@@ -85,7 +85,13 @@ func (b *builder) terraformDiff(
 	vars = append(vars, cpCfg.Vars...)
 	vars = append(vars, deployCfg.Input.Vars...)
 
-	executor := terraformprovider.NewTerraform(terraformPath, ds.AppDir, vars, deployCfg.Input.VarFiles)
+	executor := terraformprovider.NewTerraform(
+		terraformPath,
+		ds.AppDir,
+		terraformprovider.WithoutColor(),
+		terraformprovider.WithVars(vars),
+		terraformprovider.WithVarFiles(deployCfg.Input.VarFiles),
+	)
 
 	if err := executor.Init(ctx, buf); err != nil {
 		fmt.Fprintf(buf, "failed while executing terraform init (%v)\n", err)