フラスコSQLAlchemyの多くを挿入

Question

Flask sqlalchemy many-to-many insert data

に多くの私は上記のアドバイスを試してみましたが、タグを使用して、新しいポストを挿入するとき、多くの属性には多くのアペンドに次のエラーを受け取るために続けてきました。

いずれかの方向が最も高く評価されます！

1:06:22 PM web.1 | post.tags.append(post_tag)

11:06:22 PM web.1 | File "/home/trevor/Projects/trevorblog/venv/local/lib/python2.7/site-packages/sqlalchemy/orm/collections.py", line 1072, in append

11:06:22 PM web.1 | item = __set(self, item, _sa_initiator)

11:06:22 PM web.1 | File "/home/trevor/Projects/trevorblog/venv/local /lib/python2.7/site-packages/sqlalchemy/orm/collections.py", line 1044, in __set

11:06:22 PM web.1 | item = executor.fire_append_event(item, _sa_initiator)

11:06:22 PM web.1 | File "/home/trevor/Projects/trevorblog/venv/local/lib/python2.7/site-packages/sqlalchemy/orm/collections.py", line 716, in fire_append_event

11:06:22 PM web.1 | item, initiator)

11:06:22 PM web.1 | File "/home/trevor/Projects/trevorblog/venv/local/lib/python2.7/site-packages/sqlalchemy/orm/attributes.py", line 936, in fire_append_event

11:06:22 PM web.1 | initiator or self._append_token or self._init_append_token())

11:06:22 PM web.1 | File "/home/trevor/Projects/trevorblog/venv/local/lib/python2.7/site-packages/sqlalchemy/orm/attributes.py", line 1171, in emit_backref_from_collection_append_event

11:06:22 PM web.1 | child_state, child_dict = instance_state(child), \

11:06:22 PM web.1 | AttributeError: 'BaseQuery' object has no attribute '_sa_instance_state'

Model.py

blog_tag = db.Table('post_tag', 
db.Column('post_id', db.Integer, db.ForeignKey('post.id')), 
db.Column('tag_id', db.Integer, db.ForeignKey('tag.id')) 
) 

class Post(db.Model): 
    """SQLAlchemy Post object class""" 
    id = db.Column(db.Integer, primary_key=True) 
    body = db.Column(db.Text) 
    timestamp = db.Column(db.DateTime)  
    title = db.Column(db.String(50)) 
    author = db.Column(db.Integer, db.ForeignKey('user.id')) 
    uuid = db.Column(db.String(255)) 
    tags = db.relationship('Tag',secondary=blog_tag, 
         back_populates="posts") 

class Tag(db.Model): 
    """SQLAlchemy Tag object class""" 
    id=db.Column(db.Integer, primary_key=True) 
    name=db.Column(db.String, unique=True, nullable=False) 
    posts = db.relationship('Post', secondary = blog_tag, 
          back_populates = "tags") 

Views.py

@console.route('/new_post', methods=['GET', 'POST']) 
@login_required 
def new_post(): 
    post_form = PostForm() 
    if post_form.validate_on_submit(): 
     """Take the list of tags and turn them into an array""" 
     uid = uuid.uuid4() 
     post = Post() 
     post.title = post_form.title.data 
     post.body = post_form.body.data 
     post.timestamp = datetime.utcnow() 
     post.author = current_user.id 
     post.uuid = uid.hex 
     tag_string = post_form.tags.data 
     tags = tag_string.split(",") 
     for tag in tags: 
      post_tag = add_tags(tag) 
      print post_tag 
      post.tags.append(post_tag) 
     db.session.add(post) 
     db.session.commit() 
     flash (u'New Post Created!', 'alert-info') 
    return render_template('new_post.html', 
       title='Admin-New Post', 
       form=post_form) 

def add_tags(tag): 
    existing_tag = Tag.query.filter(Tag.name == tag.lower()) 
    """if it does return existing tag objec to list""" 
    if existing_tag is not None: 
     return existing_tag 
    else: 
     new_tag = Tag() 
     new_tag.name = tag.lower() 
     return new_tag 

Answer 1

これは：

existing_tag = Tag.query.filter(Tag.name == tag.lower()) 
"""if it does return existing tag objec to list""" 
if existing_tag is not None: 
    return existing_tag 

Tagを返しますが、Queryしません。タグ自体を取得するにはTag.query.filter(...).one_or_none()にします。