feat: add file upload command with multi-file and thread support

Adds `slackbuzz file upload` supporting single/multi-file uploads to
channels, DMs, and threads via the Slack V2 upload API. Also adds
files:read and files:write to both bot and user token scopes in the
app manifest.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: isaacrowntree

pkg/cmd/app/create.go

@@ -74,6 +74,8 @@ var appManifest = map[string]interface{}{
 				"channels:history",
 				"channels:read",
 				"emoji:read",
+				"files:read",
+				"files:write",
 				"groups:history",
 				"groups:read",
 				"im:history",
@@ -88,6 +90,8 @@ var appManifest = map[string]interface{}{
 			"user": []string{
 				"channels:read",
 				"chat:write",
+				"files:read",
+				"files:write",
 				"groups:read",
 				"im:read",
 				"im:write",

pkg/cmd/file/file.go

@@ -9,11 +9,12 @@ import (
 func NewCmdFile(f *cmdutil.Factory) *cobra.Command {
 	cmd := &cobra.Command{
 		Use:   "file <command>",
-		Short: "Search and manage files",
-		Long:  "Search files shared in Slack.",
+		Short: "Search, upload, and manage files",
+		Long:  "Search files shared in Slack, or upload files to channels and DMs.",
 	}
 
 	cmd.AddCommand(NewCmdSearch(f))
+	cmd.AddCommand(NewCmdUpload(f))
 
 	return cmd
 }

pkg/cmd/file/upload.go

@@ -0,0 +1,193 @@
+package file
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/slack-go/slack"
+	"github.com/spf13/cobra"
+	"github.com/triptechtravel/slackbuzz-cli/internal/api"
+	"github.com/triptechtravel/slackbuzz-cli/pkg/cmdutil"
+)
+
+type uploadOptions struct {
+	factory   *cmdutil.Factory
+	filePaths []string
+	channel   string
+	title     string
+	comment   string
+	threadTS  string
+	json      cmdutil.JSONFlags
+}
+
+// NewCmdUpload returns the "file upload" command.
+func NewCmdUpload(f *cmdutil.Factory) *cobra.Command {
+	opts := &uploadOptions{factory: f}
+
+	cmd := &cobra.Command{
+		Use:   "upload <file-path>... <channel|user>",
+		Short: "Upload files to a channel or DM",
+		Long: `Upload one or more files to a Slack channel or direct message.
+
+The last argument is the channel or user target. All preceding arguments are
+file paths to upload. Each file is uploaded individually and shared to the
+target channel.
+
+The channel argument accepts #channel-name, channel ID, @username, or user ID.`,
+		Example: `  # Upload a single file to a channel
+  slackbuzz file upload report.pdf #general
+
+  # Upload multiple files
+  slackbuzz file upload chart1.png chart2.png chart3.png #analytics
+
+  # Upload with title and comment
+  slackbuzz file upload data.csv #sales --title "Q4 Revenue" --comment "Updated data"
+
+  # Upload to a DM
+  slackbuzz file upload notes.txt @alice
+
+  # Upload to a thread
+  slackbuzz file upload results.png #dev --thread-ts 1706000000.000000`,
+		Args:              cobra.MinimumNArgs(2),
+		PersistentPreRunE: cmdutil.NeedsAuth(f),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			// Last arg is channel/user, rest are file paths
+			opts.channel = args[len(args)-1]
+			opts.filePaths = args[:len(args)-1]
+			return uploadRun(opts)
+		},
+	}
+
+	cmd.Flags().StringVar(&opts.title, "title", "", "File title in Slack (applies to first file)")
+	cmd.Flags().StringVar(&opts.comment, "comment", "", "Initial comment posted with the file(s)")
+	cmd.Flags().StringVar(&opts.threadTS, "thread-ts", "", "Thread timestamp to upload into")
+	cmdutil.AddJSONFlags(cmd, &opts.json)
+
+	return cmd
+}
+
+type uploadResult struct {
+	FileID   string `json:"file_id"`
+	Title    string `json:"title"`
+	Filename string `json:"filename"`
+	Channel  string `json:"channel"`
+}
+
+func uploadRun(opts *uploadOptions) error {
+	ios := opts.factory.IOStreams
+	cs := ios.ColorScheme()
+
+	// Validate all files exist before starting uploads
+	for _, fp := range opts.filePaths {
+		info, err := os.Stat(fp)
+		if err != nil {
+			return fmt.Errorf("file not found: %s", fp)
+		}
+		if info.IsDir() {
+			return fmt.Errorf("%s is a directory, not a file", fp)
+		}
+		if info.Size() == 0 {
+			return fmt.Errorf("%s is empty", fp)
+		}
+	}
+
+	// File uploads need files:write scope. Prefer user token so uploads
+	// appear from the user rather than the bot app.
+	client, err := opts.factory.UserClient()
+	if err != nil {
+		client, err = opts.factory.BotClient()
+		if err != nil {
+			return err
+		}
+	}
+
+	// Resolve channel/DM
+	resolver := api.NewResolver(client.Slack)
+	var channelID string
+	if api.LooksLikeUser(opts.channel) {
+		channelID, err = resolver.ResolveDM(opts.channel)
+	} else {
+		channelID, err = resolver.ResolveChannel(opts.channel)
+	}
+
+	// If resolution fails with missing scope, try the other token
+	if err != nil && api.IsMissingScopeError(err) {
+		altClient, altErr := opts.factory.UserClient()
+		if altErr != nil {
+			altClient, altErr = opts.factory.BotClient()
+		}
+		if altErr == nil {
+			fmt.Fprintf(ios.ErrOut, "%s Retrying with alternate token\n", cs.Yellow("!"))
+			altResolver := api.NewResolver(altClient.Slack)
+			if api.LooksLikeUser(opts.channel) {
+				channelID, err = altResolver.ResolveDM(opts.channel)
+			} else {
+				channelID, err = altResolver.ResolveChannel(opts.channel)
+			}
+			if err == nil {
+				client = altClient
+			}
+		}
+	}
+
+	if err != nil {
+		return fmt.Errorf("%s", api.FormatResolveError(err, opts.channel))
+	}
+
+	var results []uploadResult
+
+	for i, fp := range opts.filePaths {
+		info, _ := os.Stat(fp) // already validated above
+		fileName := filepath.Base(fp)
+
+		title := fileName
+		if opts.title != "" && i == 0 {
+			title = opts.title
+		}
+
+		params := slack.UploadFileV2Parameters{
+			File:     fp,
+			FileSize: int(info.Size()),
+			Filename: fileName,
+			Title:    title,
+			Channel:  channelID,
+		}
+
+		// Only attach the comment to the first file upload
+		if opts.comment != "" && i == 0 {
+			params.InitialComment = opts.comment
+		}
+		if opts.threadTS != "" {
+			params.ThreadTimestamp = opts.threadTS
+		}
+
+		summary, err := client.Slack.UploadFileV2(params)
+		if err != nil {
+			return fmt.Errorf("failed to upload %s: %s", fileName, api.FormatError(err))
+		}
+
+		results = append(results, uploadResult{
+			FileID:   summary.ID,
+			Title:    summary.Title,
+			Filename: fileName,
+			Channel:  channelID,
+		})
+
+		if !opts.json.WantsJSON() {
+			fmt.Fprintf(ios.Out, "%s Uploaded %s to %s\n",
+				cs.Green("✓"), cs.Bold(fileName), cs.Bold(opts.channel))
+		}
+	}
+
+	if opts.json.WantsJSON() {
+		return opts.json.OutputJSON(ios.Out, results)
+	}
+
+	if len(results) > 1 {
+		fmt.Fprintf(ios.Out, "\n%s %d files uploaded to %s\n",
+			cs.Green("✓"), len(results), cs.Bold(opts.channel))
+	}
+
+	return nil
+}