feat(export): output available fields with - filter flag

app/chat/export.go

@@ -51,7 +51,19 @@ func Export(ctx context.Context, opts *ExportOptions) error {
  return err
  }
 
- // compile filter
+ // only output available fields
+ if opts.Filter == "-" {
+ fg := texpr.NewFieldsGetter(nil)
+
+ fields, err := fg.Walk(&message{})
+ if err != nil {
+ return fmt.Errorf("failed to walk fields: %w", err)
+ }
+
+ fmt.Println(fg.Sprint(fields, true))
+ return nil
+ }
+
  filter, err := texpr.Compile(opts.Filter)
  if err != nil {
  return fmt.Errorf("failed to compile filter: %w", err)
@@ -143,7 +155,7 @@ func Export(ctx context.Context, opts *ExportOptions) error {
  continue
  }
 
- b, err := texpr.Run(filter, texpr.CovertMessage(m))
+ b, err := texpr.Run(filter, covertMessage(m))
  if err != nil {
  return fmt.Errorf("failed to run filter: %w", err)
  }

app/chat/message.go

@@ -0,0 +1,53 @@
+package chat
+
+import (
+ "github.com/gotd/td/tg"
+ "github.com/iyear/tdl/pkg/tmedia"
+ "github.com/iyear/tdl/pkg/utils"
+)
+
+type message struct {
+ Mentioned bool `comment:"Whether we were mentioned in this message"`
+ Silent bool `comment:"Whether this is a silent message (no notification triggered)"`
+ FromScheduled bool `comment:"Whether this is a scheduled message"`
+ Pinned bool `comment:"Whether this message is pinned"`
+ ID int `comment:"ID of the message"`
+ FromID int64 `comment:"ID of the sender of the message"`
+ Date int `comment:"Date of the message"`
+ Message string `comment:"The message"`
+ Media messageMedia `comment:"Media attachment"`
+ Views int `comment:"View count"`
+ Forwards int `comment:"Forward count"`
+}
+
+type messageMedia struct {
+ Name string `comment:"File name"`
+ Size int64 `comment:"File size. Unit: Byte"`
+ DC int `comment:"DC ID"`
+}
+
+func covertMessage(msg *tg.Message) (m *message) {
+ m = &message{}
+
+ m.Mentioned = msg.Mentioned
+ m.Silent = msg.Silent
+ m.FromScheduled = msg.FromScheduled
+ m.Pinned = msg.Pinned
+ m.ID = msg.ID
+ m.FromID = utils.Telegram.GetPeerID(msg.FromID)
+ m.Date = msg.Date
+ m.Message = msg.Message
+
+ if media, ok := tmedia.GetMedia(msg); ok {
+ m.Media = messageMedia{
+ Name: media.Name,
+ Size: media.Size,
+ DC: media.DC,
+ }
+ }
+
+ m.Views = msg.Views
+ m.Forwards = msg.Forwards
+
+ return m
+}

pkg/texpr/expr_test.go → app/chat/message_test.go

@@ -1,11 +1,12 @@
-package texpr
+package chat
 
 import (
+ "github.com/iyear/tdl/pkg/texpr"
  "testing"
 )
 
 func TestMessageExpr(t *testing.T) {
- msg := &Message{
+ msg := &message{
  Mentioned: true,
  Silent: false,
  FromScheduled: true,
@@ -14,7 +15,7 @@ func TestMessageExpr(t *testing.T) {
  FromID: 200,
  Date: 1684651590,
  Message: "Hello World",
- Media: MessageMedia{Size: 10240, Name: "foo.zip", DC: 3},
+ Media: messageMedia{Size: 10240, Name: "foo.zip", DC: 3},
  Views: 200,
  Forwards: 100,
  }
@@ -68,12 +69,12 @@ func TestMessageExpr(t *testing.T) {
 
  for _, test := range tests {
  t.Run(test.name, func(t *testing.T) {
- expr, err := Compile(test.expr)
+ expr, err := texpr.Compile(test.expr)
  if err != nil {
  t.Fatal(err)
  }
 
- got, err := Run(expr, msg)
+ got, err := texpr.Run(expr, msg)
  if err != nil {
  t.Fatal(err)
  }

cmd/chat.go

@@ -88,7 +88,7 @@ func NewChatExport() *cobra.Command {
  cmd.Flags().IntVar(&opts.Thread, "reply", 0, "specify channel post id")
 
  cmd.Flags().IntSliceVarP(&opts.Input, input, "i", []int{}, "input data, depends on export type")
- cmd.Flags().StringVarP(&opts.Filter, "filter", "f", "true", "filter messages by expression, see https://expr.medv.io/docs/Language-Definition for grammar")
+ cmd.Flags().StringVarP(&opts.Filter, "filter", "f", "true", "filter messages by expression, defaults to match all messages. Specify `-` to see available fields")
  cmd.Flags().StringVarP(&opts.Output, "output", "o", "tdl-export.json", "output JSON file path")
  cmd.Flags().BoolVar(&opts.WithContent, "with-content", false, "export with message content")