POC: Displayer helper

Exploration for adding a helper that builds a displayer.

internal/commands/projects/create.go

@@ -119,7 +119,7 @@ func createRun(opts *CreateOpts) error {
 	}
 
 	// Display the created project
-	d := newDisplayer(format.Pretty, true, resp.Payload.Project)
+	d := format.NewDisplayer(resp.Payload.Project, format.Pretty, projectFields)
 	if err := opts.Output.Display(d); err != nil {
 		return err
 	}

internal/commands/projects/list.go

@@ -70,6 +70,6 @@ func listRun(opts *ListOpts) error {
 		req.PaginationNextPageToken = &next
 	}
 
-	d := newDisplayer(format.Table, false, projects...)
+	d := format.NewDisplayer(projects, format.Table, projectFields)
 	return opts.Output.Display(d)
 }

internal/commands/projects/projects.go

@@ -3,9 +3,20 @@ package projects
 import (
 	"github.com/hashicorp/hcp/internal/commands/projects/iam"
 	"github.com/hashicorp/hcp/internal/pkg/cmd"
+	"github.com/hashicorp/hcp/internal/pkg/format"
 	"github.com/hashicorp/hcp/internal/pkg/heredoc"
 )
 
+var (
+	// projectFields is the set of fields to display for a project.
+	projectFields = []format.Field{
+		format.NewField("Name", "{{ .Name }}"),
+		format.NewField("ID", "{{ .ID }}"),
+		format.NewField("Description", "{{ .Description }}"),
+		format.NewField("Created At", "{{ .CreatedAt }}"),
+	}
+)
+
 func NewCmdProjects(ctx *cmd.Context) *cmd.Command {
 	cmd := &cmd.Command{
 		Name:      "projects",

internal/commands/projects/read.go

@@ -26,7 +26,7 @@ func NewCmdRead(ctx *cmd.Context, runF func(*ReadOpts) error) *cmd.Command {
 		LongHelp:  "Show metadata for the project.",
 		Examples: []cmd.Example{
 			{
-				Preamble: "Read a project:",
+				Preamble: "Read a project.",
 				Command:  "$ hcp projects read --project=cd3d34d5-ceeb-493d-b004-9297365a01af",
 			},
 		},
@@ -61,6 +61,6 @@ func readRun(opts *ReadOpts) error {
 		return fmt.Errorf("failed to read project: %w", err)
 	}
 
-	d := newDisplayer(format.Pretty, true, resp.Payload.Project)
+	d := format.NewDisplayer(resp.Payload.Project, format.Pretty, projectFields)
 	return opts.Output.Display(d)
 }

internal/pkg/format/helper.go

@@ -0,0 +1,27 @@
+package format
+
+// NewField creates a new Field with the given name and value format string. See
+// the Field struct for more information.
+func NewField(name, valueFormat string) Field {
+	return Field{Name: name, ValueFormat: valueFormat}
+}
+
+// NewDisplayer creates a new Displayer with the given payload, default format,
+// and fields.
+func NewDisplayer[T any](payload T, defaultFormat Format, fields []Field) Displayer {
+	return &internalDisplayer[T]{
+		payload:       payload,
+		fields:        fields,
+		defaultFormat: defaultFormat,
+	}
+}
+
+type internalDisplayer[T any] struct {
+	payload       T
+	fields        []Field
+	defaultFormat Format
+}
+
+func (i *internalDisplayer[T]) DefaultFormat() Format   { return i.defaultFormat }
+func (i *internalDisplayer[T]) FieldTemplates() []Field { return i.fields }
+func (i *internalDisplayer[T]) Payload() any            { return i.payload }