d2plugin: Dedup plugins array

Closes #590

d2plugin/exec.go

@@ -40,9 +40,10 @@ import (
 type execPlugin struct {
 	path string
 	opts map[string]string
+	info *PluginInfo
 }
 
-func (p execPlugin) Flags(ctx context.Context) (_ []PluginSpecificFlag, err error) {
+func (p *execPlugin) Flags(ctx context.Context) (_ []PluginSpecificFlag, err error) {
 	ctx, cancel := context.WithTimeout(ctx, time.Second*10)
 	defer cancel()
 	cmd := exec.CommandContext(ctx, p.path, "flags")
@@ -92,7 +93,11 @@ func (p *execPlugin) HydrateOpts(opts []byte) error {
 	return nil
 }
 
-func (p execPlugin) Info(ctx context.Context) (_ *PluginInfo, err error) {
+func (p *execPlugin) Info(ctx context.Context) (_ *PluginInfo, err error) {
+	if p.info != nil {
+		return p.info, nil
+	}
+
 	ctx, cancel := context.WithTimeout(ctx, time.Second*10)
 	defer cancel()
 	cmd := exec.CommandContext(ctx, p.path, "info")
@@ -114,10 +119,11 @@ func (p execPlugin) Info(ctx context.Context) (_ *PluginInfo, err error) {
 		return nil, fmt.Errorf("failed to unmarshal json: %w", err)
 	}
 
+	p.info = &info
 	return &info, nil
 }
 
-func (p execPlugin) Layout(ctx context.Context, g *d2graph.Graph) error {
+func (p *execPlugin) Layout(ctx context.Context, g *d2graph.Graph) error {
 	ctx, cancel := context.WithTimeout(ctx, time.Minute)
 	defer cancel()
 
@@ -152,7 +158,7 @@ func (p execPlugin) Layout(ctx context.Context, g *d2graph.Graph) error {
 	return nil
 }
 
-func (p execPlugin) PostProcess(ctx context.Context, in []byte) ([]byte, error) {
+func (p *execPlugin) PostProcess(ctx context.Context, in []byte) ([]byte, error) {
 	ctx, cancel := context.WithTimeout(ctx, time.Minute)
 	defer cancel()
 

d2plugin/plugin.go

@@ -80,36 +80,54 @@ type PluginInfo struct {
 
 const binaryPrefix = "d2plugin-"
 
-func ListPlugins(ctx context.Context) ([]*PluginInfo, error) {
+func ListPlugins(ctx context.Context) ([]Plugin, error) {
 	// 1. Run Info on all bundled plugins in the global plugins array.
 	//    - set Type for each bundled plugin to "bundled".
 	// 2. Iterate through directories in $PATH and look for executables within these
 	//    directories with the prefix d2plugin-*
 	// 3. Run each plugin binary with the argument info. e.g. d2plugin-dagre info
 
-	var infoSlice []*PluginInfo
+	var ps []Plugin
-
+	ps = append(ps, plugins...)
-	for _, p := range plugins {
-		info, err := p.Info(ctx)
-		if err != nil {
-			return nil, err
-		}
-		info.Type = "bundled"
-		infoSlice = append(infoSlice, info)
-	}
 
 	matches, err := xexec.SearchPath(binaryPrefix)
 	if err != nil {
 		return nil, err
 	}
+BINARY_PLUGINS_LOOP:
 	for _, path := range matches {
 		p := &execPlugin{path: path}
 		info, err := p.Info(ctx)
 		if err != nil {
 			return nil, err
 		}
-		info.Type = "binary"
+		for _, p2 := range ps {
-		info.Path = path
+			info2, err := p2.Info(ctx)
+			if err != nil {
+				return nil, err
+			}
+			if info.Name == info2.Name {
+				continue BINARY_PLUGINS_LOOP
+			}
+		}
+		ps = append(ps, p)
+	}
+	return ps, nil
+}
+
+func ListPluginInfos(ctx context.Context, ps []Plugin) ([]*PluginInfo, error) {
+	var infoSlice []*PluginInfo
+	for _, p := range ps {
+		info, err := p.Info(ctx)
+		if err != nil {
+			return nil, err
+		}
+		if ep, ok := p.(*execPlugin); ok {
+			info.Type = "binary"
+			info.Path = ep.path
+		} else {
+			info.Type = "bundled"
+		}
 		infoSlice = append(infoSlice, info)
 	}
 
@@ -123,41 +141,22 @@ func ListPlugins(ctx context.Context) ([]*PluginInfo, error) {
 //    **NOTE** When D2 upgrades to go 1.19, remember to ignore exec.ErrDot
 // 3. If such a binary is found, it builds an execPlugin in exec.go
 //    to get a plugin implementation around the binary and returns it.
-func FindPlugin(ctx context.Context, name string) (Plugin, string, error) {
+func FindPlugin(ctx context.Context, ps []Plugin, name string) (Plugin, error) {
-	for _, p := range plugins {
+	for _, p := range ps {
 		info, err := p.Info(ctx)
-		if err != nil {
-			return nil, "", err
-		}
-		if info.Name == name {
-			return p, "", nil
-		}
-	}
-
-	path, err := exec.LookPath(binaryPrefix + name)
-	if err != nil {
-		return nil, "", err
-	}
-
-	return &execPlugin{path: path}, path, nil
-}
-
-func ListPluginFlags(ctx context.Context) ([]PluginSpecificFlag, error) {
-	var out []PluginSpecificFlag
-	for _, p := range plugins {
-		flags, err := p.Flags(ctx)
 		if err != nil {
 			return nil, err
 		}
-		out = append(out, flags...)
+		if info.Name == name {
+			return p, nil
+		}
 	}
+	return nil, exec.ErrNotFound
+}
 
-	matches, err := xexec.SearchPath(binaryPrefix)
+func ListPluginFlags(ctx context.Context, ps []Plugin) ([]PluginSpecificFlag, error) {
-	if err != nil {
+	var out []PluginSpecificFlag
-		return nil, err
+	for _, p := range ps {
-	}
-	for _, path := range matches {
-		p := &execPlugin{path: path}
 		flags, err := p.Flags(ctx)
 		if err != nil {
 			return nil, err

help.go

@@ -39,23 +39,23 @@ See more docs and the source code at https://oss.terrastruct.com/d2
 `, filepath.Base(ms.Name), ms.Opts.Defaults())
 }
 
-func layoutCmd(ctx context.Context, ms *xmain.State) error {
+func layoutCmd(ctx context.Context, ms *xmain.State, ps []d2plugin.Plugin) error {
 	if len(ms.Opts.Flags.Args()) == 1 {
-		return shortLayoutHelp(ctx, ms)
+		return shortLayoutHelp(ctx, ms, ps)
 	} else if len(ms.Opts.Flags.Args()) == 2 {
-		return longLayoutHelp(ctx, ms)
+		return longLayoutHelp(ctx, ms, ps)
 	} else {
-		return pluginSubcommand(ctx, ms)
+		return pluginSubcommand(ctx, ms, ps)
 	}
 }
 
-func shortLayoutHelp(ctx context.Context, ms *xmain.State) error {
+func shortLayoutHelp(ctx context.Context, ms *xmain.State, ps []d2plugin.Plugin) error {
 	var pluginLines []string
-	plugins, err := d2plugin.ListPlugins(ctx)
+	pinfos, err := d2plugin.ListPluginInfos(ctx, ps)
 	if err != nil {
 		return err
 	}
-	for _, p := range plugins {
+	for _, p := range pinfos {
 		var l string
 		if p.Type == "bundled" {
 			l = fmt.Sprintf("%s (bundled) - %s", p.Name, p.ShortHelp)
@@ -82,40 +82,43 @@ See more docs at https://oss.terrastruct.com/d2
 	return nil
 }
 
-func longLayoutHelp(ctx context.Context, ms *xmain.State) error {
+func longLayoutHelp(ctx context.Context, ms *xmain.State, ps []d2plugin.Plugin) error {
 	layout := ms.Opts.Flags.Arg(1)
-	plugin, path, err := d2plugin.FindPlugin(ctx, layout)
+	plugin, err := d2plugin.FindPlugin(ctx, ps, layout)
-	if errors.Is(err, exec.ErrNotFound) {
+	if err != nil {
-		return layoutNotFound(ctx, layout)
+		if errors.Is(err, exec.ErrNotFound) {
+			return layoutNotFound(ctx, ps, layout)
+		}
+		return err
 	}
 
-	pluginLocation := "bundled"
+	pinfo, err := plugin.Info(ctx)
-	if path != "" {
-		pluginLocation = fmt.Sprintf("executable plugin at %s", humanPath(path))
-	}
-
-	pluginInfo, err := plugin.Info(ctx)
 	if err != nil {
 		return err
 	}
 
-	if !strings.HasSuffix(pluginInfo.LongHelp, "\n") {
+	plocation := pinfo.Type
-		pluginInfo.LongHelp += "\n"
+	if pinfo.Type == "binary" {
+		plocation = fmt.Sprintf("executable plugin at %s", humanPath(pinfo.Path))
+	}
+
+	if !strings.HasSuffix(pinfo.LongHelp, "\n") {
+		pinfo.LongHelp += "\n"
 	}
 	fmt.Fprintf(ms.Stdout, `%s (%s):
 
-%s`, pluginInfo.Name, pluginLocation, pluginInfo.LongHelp)
+%s`, pinfo.Name, plocation, pinfo.LongHelp)
 
 	return nil
 }
 
-func layoutNotFound(ctx context.Context, layout string) error {
+func layoutNotFound(ctx context.Context, ps []d2plugin.Plugin, layout string) error {
-	var names []string
+	pinfos, err := d2plugin.ListPluginInfos(ctx, ps)
-	plugins, err := d2plugin.ListPlugins(ctx)
 	if err != nil {
 		return err
 	}
-	for _, p := range plugins {
+	var names []string
+	for _, p := range pinfos {
 		names = append(names, p.Name)
 	}
 
@@ -126,11 +129,14 @@ For more information on setup, please visit https://github.com/terrastruct/d2.`,
 		layout, strings.Join(names, ", "))
 }
 
-func pluginSubcommand(ctx context.Context, ms *xmain.State) error {
+func pluginSubcommand(ctx context.Context, ms *xmain.State, ps []d2plugin.Plugin) error {
 	layout := ms.Opts.Flags.Arg(1)
-	plugin, _, err := d2plugin.FindPlugin(ctx, layout)
+	plugin, err := d2plugin.FindPlugin(ctx, ps, layout)
-	if errors.Is(err, exec.ErrNotFound) {
+	if err != nil {
-		return layoutNotFound(ctx, layout)
+		if errors.Is(err, exec.ErrNotFound) {
+			return layoutNotFound(ctx, ps, layout)
+		}
+		return err
 	}
 
 	ms.Opts.Args = ms.Opts.Flags.Args()[2:]

main.go

@@ -75,7 +75,11 @@ func run(ctx context.Context, ms *xmain.State) (err error) {
 		return err
 	}
 
-	err = populateLayoutOpts(ctx, ms)
+	ps, err := d2plugin.ListPlugins(ctx)
+	if err != nil {
+		return err
+	}
+	err = populateLayoutOpts(ctx, ms, ps)
 	if err != nil {
 		return err
 	}
@@ -93,7 +97,7 @@ func run(ctx context.Context, ms *xmain.State) (err error) {
 	if len(ms.Opts.Flags.Args()) > 0 {
 		switch ms.Opts.Flags.Arg(0) {
 		case "layout":
-			return layoutCmd(ctx, ms)
+			return layoutCmd(ctx, ms, ps)
 		case "fmt":
 			return fmtCmd(ctx, ms)
 		case "version":
@@ -142,10 +146,11 @@ func run(ctx context.Context, ms *xmain.State) (err error) {
 	}
 	ms.Log.Debug.Printf("using theme %s (ID: %d)", match.Name, *themeFlag)
 
-	plugin, path, err := d2plugin.FindPlugin(ctx, *layoutFlag)
+	plugin, err := d2plugin.FindPlugin(ctx, ps, *layoutFlag)
-	if errors.Is(err, exec.ErrNotFound) {
+	if err != nil {
-		return layoutNotFound(ctx, *layoutFlag)
+		if errors.Is(err, exec.ErrNotFound) {
-	} else if err != nil {
+			return layoutNotFound(ctx, ps, *layoutFlag)
+		}
 		return err
 	}
 
@@ -154,11 +159,15 @@ func run(ctx context.Context, ms *xmain.State) (err error) {
 		return err
 	}
 
-	pluginLocation := "bundled"
+	pinfo, err := plugin.Info(ctx)
-	if path != "" {
+	if err != nil {
-		pluginLocation = fmt.Sprintf("executable plugin at %s", humanPath(path))
+		return err
 	}
-	ms.Log.Debug.Printf("using layout plugin %s (%s)", *layoutFlag, pluginLocation)
+	plocation := pinfo.Type
+	if pinfo.Type == "binary" {
+		plocation = fmt.Sprintf("executable plugin at %s", humanPath(pinfo.Path))
+	}
+	ms.Log.Debug.Printf("using layout plugin %s (%s)", *layoutFlag, plocation)
 
 	var pw png.Playwright
 	if filepath.Ext(outputPath) == ".png" {
@@ -299,8 +308,8 @@ func DiscardSlog(ctx context.Context) context.Context {
 	return ctxlog.With(ctx, slog.Make(sloghuman.Sink(io.Discard)))
 }
 
-func populateLayoutOpts(ctx context.Context, ms *xmain.State) error {
+func populateLayoutOpts(ctx context.Context, ms *xmain.State, ps []d2plugin.Plugin) error {
-	pluginFlags, err := d2plugin.ListPluginFlags(ctx)
+	pluginFlags, err := d2plugin.ListPluginFlags(ctx, ps)
 	if err != nil {
 		return err
 	}