feat: Implement legacy post handling and conversion for backward comp…

…atibility

internal/web/blog/model/posts.go

@@ -47,6 +47,126 @@ type Post struct {
 	ArweaveId []ArweaveHistoryItem `bson:"arweave_id" json:"arweave_id"`
 }
 
+type legacyOid struct {
+	Oid string `json:"$oid"`
+}
+
+func (o legacyOid) ObjectId() (primitive.ObjectID, error) {
+	return primitive.ObjectIDFromHex(o.Oid)
+}
+
+type legacyTime struct {
+	Date string `json:"$date"`
+}
+
+func (t legacyTime) Time() (time.Time, error) {
+	return time.Parse(time.RFC3339, t.Date)
+}
+
+type legacyI18N struct {
+	UpdateAt legacyTime       `bson:"update_at" json:"update_at"`
+	EnUs     PostI18NLanguage `bson:"en_us" json:"en_us"`
+}
+
+func (i legacyI18N) I18N() (PostI18N, error) {
+	updateAt, err := i.UpdateAt.Time()
+	if err != nil {
+		return PostI18N{}, err
+	}
+
+	return PostI18N{
+		UpdateAt: updateAt,
+		EnUs:     i.EnUs,
+	}, nil
+}
+
+// LegacyPost The old article history JSON was generated by Python,
+// and the generated keys and structure are inconsistent with the new Go code,
+// so the structure is redefined here to facilitate the conversion of the old data to the new data.
+type LegacyPost struct {
+	// ID unique identifier for the post
+	ID legacyOid `bson:"_id,omitempty" json:"_id"`
+	// CreatedAt time when the post was created
+	CreatedAt legacyTime `bson:"post_created_at" json:"post_created_at"`
+	// ModifiedAt time when the post was last modified
+	ModifiedAt legacyTime `bson:"post_modified_gmt" json:"post_modified_gmt"`
+	// Title title of the post
+	Title string `bson:"post_title" json:"post_title"`
+	// Type type of the post
+	Type string `bson:"post_type" json:"post_type"`
+	// Status status of the post
+	Status string `bson:"post_status" json:"post_status"`
+	// Name name of the post
+	Name string `bson:"post_name" json:"post_name"`
+	// Content content of the post
+	Content string `bson:"post_content" json:"post_content"`
+	// Markdown markdown content of the post
+	Markdown string `bson:"post_markdown" json:"post_markdown"`
+	// Author author of the post
+	Author legacyOid `bson:"post_author,omitempty" json:"post_author"`
+	// Menu menu of the post
+	Menu string `bson:"post_menu" json:"post_menu"`
+	// Password password of the post
+	Password string `bson:"post_password" json:"-"`
+	// Category category of the post
+	Category legacyOid `bson:"category,omitempty" json:"category"`
+	// Tags tags of the post
+	Tags []string `bson:"post_tags" json:"post_tags"`
+	// Hidden whether the post is hidden or not
+	Hidden bool `bson:"hidden" json:"hidden"`
+	// I18N internationalization of the post
+	I18N legacyI18N `bson:"i18n" json:"i18n"`
+	// Language language of the post content or markdown
+	Language string `bson:"-" json:"language"`
+	// ArweaveId arweave id of the post
+	ArweaveId []ArweaveHistoryItem `bson:"arweave_id" json:"arweave_id"`
+}
+
+func (lp LegacyPost) Post() (p *Post, err error) {
+	p = new(Post)
+	if p.I18N, err = lp.I18N.I18N(); err != nil {
+		return nil, err
+	}
+
+	if p.CreatedAt, err = lp.CreatedAt.Time(); err != nil {
+		return nil, err
+	}
+
+	if p.ModifiedAt, err = lp.ModifiedAt.Time(); err != nil {
+		return nil, err
+	}
+
+	p.ID, err = lp.ID.ObjectId()
+	if err != nil {
+		return nil, err
+	}
+
+	p.Author, err = lp.Author.ObjectId()
+	if err != nil {
+		return nil, err
+	}
+
+	p.Category, err = lp.Category.ObjectId()
+	if err != nil {
+		return nil, err
+	}
+
+	p.Title = lp.Title
+	p.Type = lp.Type
+	p.Status = lp.Status
+	p.Name = lp.Name
+	p.Content = lp.Content
+	p.Markdown = lp.Markdown
+	p.Menu = lp.Menu
+	p.Password = lp.Password
+	p.Tags = lp.Tags
+	p.Hidden = lp.Hidden
+	p.Language = lp.Language
+	p.ArweaveId = lp.ArweaveId
+
+	return p, nil
+}
+
 // ArweaveHistoryItem arweave history item
 type ArweaveHistoryItem struct {
 	Time time.Time `bson:"time" json:"time"`

internal/web/blog/service/posts.go

@@ -144,6 +144,21 @@ func (s *Blog) LoadPostInfo(ctx context.Context) (*dto.PostInfo, error) {
 	}, nil
 }
 
+func makeReader(cnt []byte) (reader io.Reader, err error) {
+	if bytes.HasPrefix(cnt, []byte("gz::")) {
+		cnt = cnt[4:]
+
+		reader, err = gzip.NewReader(bytes.NewReader(cnt))
+		if err != nil {
+			return nil, errors.Wrap(err, "new gzip reader")
+		}
+	} else {
+		reader = bytes.NewBuffer(cnt)
+	}
+
+	return reader, nil
+}
+
 // LoadPostHistory load post history by arweave file id
 func (s *Blog) LoadPostHistory(ctx context.Context, fileID string, language models.Language) (*model.Post, error) {
 	logger := gmw.GetLogger(ctx)
@@ -172,21 +187,27 @@ func (s *Blog) LoadPostHistory(ctx context.Context, fileID string, language mode
 		return nil, errors.Wrap(err, "read all")
 	}
 
-	var reader io.Reader
-	if bytes.HasPrefix(cnt, []byte("gz::")) {
-		cnt = cnt[4:]
-
-		reader, err = gzip.NewReader(bytes.NewReader(cnt))
-		if err != nil {
-			return nil, errors.Wrap(err, "new gzip reader")
-		}
-	} else {
-		reader = bytes.NewReader(cnt)
+	reader, err := makeReader(cnt)
+	if err != nil {
+		return nil, errors.Wrap(err, "get reader")
 	}
 
 	post := new(model.Post)
 	if err = json.NewDecoder(reader).Decode(post); err != nil {
-		return nil, errors.Wrap(err, "decode post")
+		// try legacy struct
+		reader, err := makeReader(cnt)
+		if err != nil {
+			return nil, errors.Wrap(err, "get reader")
+		}
+
+		legacyPost := new(model.LegacyPost)
+		if err2 := json.NewDecoder(reader).Decode(legacyPost); err2 != nil {
+			return nil, errors.Wrap(errors.Join(err, err2), "cannot decode post by legacy struct")
+		}
+
+		if post, err = legacyPost.Post(); err != nil {
+			return nil, errors.Wrap(err, "convert legacy to current post format")
+		}
 	}
 
 	if language != models.LanguageZhCn && post.I18N.EnUs.PostContent != "" {