tmeckel · tmeckel · Aug 12, 2023 · Aug 12, 2023 · Aug 12, 2023 · Aug 12, 2023
diff --git a/docs/azdo_help_reference.md b/docs/azdo_help_reference.md
@@ -77,7 +77,7 @@ Work with Azure DevOps Projects.
 List the projects for an organization
 
 ```
-    --format string         Output format: {json}
+    --format string         Output format: {json} (default "table")
 -l, --limit int             Maximum number of projects to fetch (default 30)
 -o, --organization string   Get per-organization configuration
     --state string          Project state filter: {deleting|new|wellFormed|createPending|all|unchanged|deleted}
@@ -103,7 +103,7 @@ Clone a repository locally
 List repositories of a project inside an organization
 
 ```
-    --format string         Output format: {json}
+    --format string         Output format: {json} (default "table")
     --include-hidden        Include hidden repositories
 -L, --limit int             Maximum number of repositories to list (default 30)
 -o, --organization string   Get per-organization configuration

diff --git a/internal/cmd/project/list/list.go b/internal/cmd/project/list/list.go
@@ -7,7 +7,7 @@ import (
 	"github.com/microsoft/azure-devops-go-api/azuredevops/v7/core"
 	"github.com/spf13/cobra"
 	"github.com/tmeckel/azdo-cli/internal/cmd/util"
-	"github.com/tmeckel/azdo-cli/internal/tableprinter"
+	"github.com/tmeckel/azdo-cli/internal/printer"
 )
 
 type listOptions struct {
@@ -37,7 +37,7 @@ func NewCmdProjectList(ctx util.CmdContext) *cobra.Command {
 	}
 
 	cmd.Flags().StringVarP(&opts.organizationName, "organization", "o", "", "Get per-organization configuration")
-	util.StringEnumFlag(cmd, &opts.format, "format", "", "", []string{"json"}, "Output format")
+	util.StringEnumFlag(cmd, &opts.format, "format", "", "table", []string{"json"}, "Output format")
 	util.StringEnumFlag(cmd, &opts.state, "state", "", "",
 		[]string{
 			string(core.ProjectStateValues.Deleting),
@@ -95,14 +95,14 @@ func runList(ctx util.CmdContext, opts *listOptions) (err error) {
 		return util.NewNoResultsError(fmt.Sprintf("No projects found for organization %s", organizationName))
 	}
 
-	tp, err := ctx.TablePrinter()
+	tp, err := ctx.Printer(opts.format)
 	if err != nil {
 		return
 	}
 
-	tp.HeaderRow("ID", "Name", "State")
+	tp.AddColumns("ID", "Name", "State")
 	for _, p := range res.Value {
-		tp.AddField(p.Id.String(), tableprinter.WithTruncate(nil))
+		tp.AddField(p.Id.String(), printer.WithTruncate(nil))
 		tp.AddField(*p.Name)
 		tp.AddField(string(*p.State))
 		tp.EndRow()

diff --git a/internal/cmd/repo/list/list.go b/internal/cmd/repo/list/list.go
@@ -7,7 +7,7 @@ import (
 	"github.com/microsoft/azure-devops-go-api/azuredevops/v7/git"
 	"github.com/spf13/cobra"
 	"github.com/tmeckel/azdo-cli/internal/cmd/util"
-	"github.com/tmeckel/azdo-cli/internal/tableprinter"
+	"github.com/tmeckel/azdo-cli/internal/printer"
 )
 
 type listOptions struct {
@@ -48,7 +48,7 @@ func NewCmdRepoList(ctx util.CmdContext) *cobra.Command {
 	cmd.Flags().StringVarP(&opts.organizationName, "organization", "o", "", "Get per-organization configuration")
 	cmd.Flags().IntVarP(&opts.limit, "limit", "L", 30, "Maximum number of repositories to list")
 	util.StringEnumFlag(cmd, &opts.visibility, "visibility", "", "", []string{"public", "private"}, "Filter by repository visibility")
-	util.StringEnumFlag(cmd, &opts.format, "format", "", "", []string{"json"}, "Output format")
+	util.StringEnumFlag(cmd, &opts.format, "format", "", "table", []string{"json"}, "Output format")
 	cmd.Flags().BoolVar(&opts.includeHidden, "include-hidden", false, "Include hidden repositories")
 
 	return cmd
@@ -95,14 +95,14 @@ func runList(ctx util.CmdContext, opts *listOptions) (err error) {
 		return util.NewNoResultsError(fmt.Sprintf("No repositories found for project %s and organization %s", opts.project, organizationName))
 	}
 
-	tp, err := ctx.TablePrinter()
+	tp, err := ctx.Printer(opts.format)
 	if err != nil {
 		return
 	}
 
-	tp.HeaderRow("ID", "Name", "SSHUrl", "HTTPUrl")
+	tp.AddColumns("ID", "Name", "SSHUrl", "HTTPUrl")
 	for _, p := range *res {
-		tp.AddField(p.Id.String(), tableprinter.WithTruncate(nil))
+		tp.AddField(p.Id.String(), printer.WithTruncate(nil))
 		tp.AddField(*p.Name)
 		tp.AddField(*p.SshUrl)
 		tp.AddField(*p.WebUrl)

diff --git a/internal/cmd/util/cmd_context.go b/internal/cmd/util/cmd_context.go
@@ -9,8 +9,8 @@ import (
 	"github.com/tmeckel/azdo-cli/internal/config"
 	"github.com/tmeckel/azdo-cli/internal/git"
 	"github.com/tmeckel/azdo-cli/internal/iostreams"
+	"github.com/tmeckel/azdo-cli/internal/printer"
 	"github.com/tmeckel/azdo-cli/internal/prompter"
-	"github.com/tmeckel/azdo-cli/internal/tableprinter"
 )
 
 type CmdContext interface {
@@ -19,7 +19,7 @@ type CmdContext interface {
 	Config() (config.Config, error)
 	Connection(organization string) (*azuredevops.Connection, error)
 	IOStreams() (*iostreams.IOStreams, error)
-	TablePrinter() (tableprinter.TablePrinter, error)
+	Printer(string) (printer.Printer, error)
 	GitClient() (*git.Client, error)
 }
 
@@ -98,8 +98,15 @@ func (c *cmdContext) IOStreams() (*iostreams.IOStreams, error) {
 	return c.ioStreams, nil
 }
 
-func (c *cmdContext) TablePrinter() (tp tableprinter.TablePrinter, err error) {
-	tp, err = newTablePrinter(c.ioStreams)
+func (c *cmdContext) Printer(t string) (p printer.Printer, err error) {
+	switch t {
+	case "table":
+		p, err = newTablePrinter(c.ioStreams)
+	case "json":
+		p, err = printer.NewJSONPrinter(c.ioStreams.Out)
+	default:
+		return nil, printer.NewUnsupportedPrinterError(t)
+	}
 	return
 }
 
@@ -153,11 +160,11 @@ func newPrompter(cfg config.Config, io *iostreams.IOStreams) (p prompter.Prompte
 	return
 }
 
-func newTablePrinter(ios *iostreams.IOStreams) (tableprinter.TablePrinter, error) {
+func newTablePrinter(ios *iostreams.IOStreams) (printer.TablePrinter, error) {
 	maxWidth := 80
 	isTTY := ios.IsStdoutTTY()
 	if isTTY {
 		maxWidth = ios.TerminalWidth()
 	}
-	return tableprinter.New(ios.Out, isTTY, maxWidth)
+	return printer.NewTablePrinter(ios.Out, isTTY, maxWidth)
 }
diff --git a/internal/printer/json.go b/internal/printer/json.go
@@ -0,0 +1,59 @@
+package printer
+
+import (
+	"encoding/json"
+	"io"
+	"time"
+
+	"github.com/tmeckel/azdo-cli/internal/text"
+)
+
+type JSONPrinter interface {
+	Printer
+}
+
+// NewJSONPrinter initializes a table printer with terminal mode and terminal width. When terminal mode is enabled, the
+// output will be human-readable, column-formatted to fit available width, and rendered with color support.
+// In non-terminal mode, the output is tab-separated and all truncation of values is disabled.
+func NewJSONPrinter(w io.Writer) (jp JSONPrinter, err error) {
+	jp = &jsonPrinter{
+		out:           json.NewEncoder(w),
+		columns:       []string{},
+		currentColumn: -1,
+		rows:          []map[string]string{},
+	}
+	return
+}
+
+type jsonPrinter struct {
+	out           *json.Encoder
+	columns       []string
+	currentColumn int
+	rows          []map[string]string
+}
+
+func (jp *jsonPrinter) AddColumns(columns ...string) {
+	jp.columns = append(jp.columns, columns...)
+}
+
+func (jp *jsonPrinter) AddField(s string, opts ...FieldOption) {
+	if jp.currentColumn < 0 {
+		jp.rows = append(jp.rows, map[string]string{})
+	}
+	jp.currentColumn++
+	rowI := len(jp.rows) - 1
+	jp.rows[rowI][jp.columns[jp.currentColumn]] = s
+}
+
+func (jp *jsonPrinter) AddTimeField(now, t time.Time, c func(string) string) {
+	tf := text.FuzzyAgo(now, t)
+	jp.AddField(tf)
+}
+
+func (jp *jsonPrinter) EndRow() {
+	jp.currentColumn = -1
+}
+
+func (jp *jsonPrinter) Render() error {
+	return jp.out.Encode(jp.rows)
+}
diff --git a/internal/printer/printer.go b/internal/printer/printer.go
@@ -0,0 +1,47 @@
+package printer
+
+import (
+	"fmt"
+	"time"
+)
+
+type UnsupportedPrinterError struct {
+	ptype string
+}
+
+func (e *UnsupportedPrinterError) Error() string {
+	return fmt.Sprintf("unsupported printer type %s", e.ptype)
+}
+
+func NewUnsupportedPrinterError(ptype string) error {
+	return &UnsupportedPrinterError{
+		ptype: ptype,
+	}
+}
+
+type Printer interface {
+	AddColumns(columns ...string)
+	AddField(string, ...FieldOption)
+	AddTimeField(now, t time.Time, c func(string) string)
+	EndRow()
+	Render() error
+}
+
+type FieldOption func(*tableField)
+
+// WithTruncate overrides the truncation function for the field. The function should transform a string
+// argument into a string that fits within the given display width. The default behavior is to truncate the
+// value by adding "..." in the end. Pass nil to disable truncation for this value.
+func WithTruncate(fn func(int, string) string) FieldOption {
+	return func(f *tableField) {
+		f.truncateFunc = fn
+	}
+}
+
+// WithColor sets the color function for the field. The function should transform a string value by wrapping
+// it in ANSI escape codes. The color function will not be used if the table was initialized in non-terminal mode.
+func WithColor(fn func(string) string) FieldOption {
+	return func(f *tableField) {
+		f.colorFunc = fn
+	}
+}
diff --git a/internal/tableprinter/table.go → internal/printer/table.go b/internal/tableprinter/table.go → internal/printer/table.go
@@ -1,8 +1,8 @@
-// Package tableprinter facilitates rendering column-formatted data to a terminal and TSV-formatted data to
+// TablePrinter facilitates rendering column-formatted data to a terminal and TSV-formatted data to
 // a script or a file. It is suitable for presenting tabular data in a human-readable format that is
 // guaranteed to fit within the given viewport, while at the same time offering the same data in a
 // machine-readable format for scripts.
-package tableprinter
+package printer
 
 import (
 	"fmt"
@@ -13,37 +13,14 @@ import (
 	"github.com/tmeckel/azdo-cli/internal/text"
 )
 
-type FieldOption func(*tableField)
-
 type TablePrinter interface {
-	AddField(string, ...FieldOption)
-	AddTimeField(now, t time.Time, c func(string) string)
-	HeaderRow(columns ...string)
-	EndRow()
-	Render() error
-}
-
-// WithTruncate overrides the truncation function for the field. The function should transform a string
-// argument into a string that fits within the given display width. The default behavior is to truncate the
-// value by adding "..." in the end. Pass nil to disable truncation for this value.
-func WithTruncate(fn func(int, string) string) FieldOption {
-	return func(f *tableField) {
-		f.truncateFunc = fn
-	}
-}
-
-// WithColor sets the color function for the field. The function should transform a string value by wrapping
-// it in ANSI escape codes. The color function will not be used if the table was initialized in non-terminal mode.
-func WithColor(fn func(string) string) FieldOption {
-	return func(f *tableField) {
-		f.colorFunc = fn
-	}
+	Printer
 }
 
-// New initializes a table printer with terminal mode and terminal width. When terminal mode is enabled, the
+// NewTablePrinter initializes a table printer with terminal mode and terminal width. When terminal mode is enabled, the
 // output will be human-readable, column-formatted to fit available width, and rendered with color support.
 // In non-terminal mode, the output is tab-separated and all truncation of values is disabled.
-func New(w io.Writer, isTTY bool, maxWidth int) (tp TablePrinter, err error) {
+func NewTablePrinter(w io.Writer, isTTY bool, maxWidth int) (tp TablePrinter, err error) {
 	if isTTY {
 		tp = &ttyTablePrinter{
 			out:      w,
@@ -71,7 +48,7 @@ type ttyTablePrinter struct {
 
 var _ TablePrinter = &ttyTablePrinter{}
 
-func (t *ttyTablePrinter) HeaderRow(columns ...string) {
+func (t *ttyTablePrinter) AddColumns(columns ...string) {
 	for _, col := range columns {
 		t.AddField(strings.ToUpper(col))
 	}
@@ -249,7 +226,7 @@ func (t *tsvTablePrinter) AddField(text string, opts ...FieldOption) {
 	t.currentCol++
 }
 
-func (t *tsvTablePrinter) HeaderRow(columns ...string) {
+func (t *tsvTablePrinter) AddColumns(columns ...string) {
 }
 
 func (t *tsvTablePrinter) EndRow() {