添加多个图片 Mongoengine

Question

我在Flask和Mongoengine中创建了一种博客，它可以跟踪某台机器生产的每一件作品。用户还可以对每个制作的部分添加评论。想象一下，它就像一个博客，里面有帖子（包含每个部分的信息），并且可以在每个帖子中添加评论.我想做的是，给用户添加评论的能力。多重 图片同时在其评论中。此外，我还想把图片存储在MongoDB中。对于单张图片这样做是没有问题的，但是对于更多的图片，我没有找到这样做的方法。

我最初的代码是：

模型.py

    class Comment(Document):
        #
        meta = {'collection': 'comments'}
        #
        commentPartID = fields.StringField(required=True)
        #
        commentTitle = fields.StringField(required=True)
        commentContent = fields.StringField(required=True)
        commentInsertedAt = fields.DateTimeField(required=True, default=datetime.datetime.utcnow)
        commentAuthor = fields.StringField(required=True)
        #
        commentImage = fields.ListField(fields.ImageField(size=(1200,800,False), thumbnail_size=(300,200,False), collection_name='images'))
        commentCategory = fields.StringField()
        commentTag = fields.StringField()

路由.py

    def create_comment(machine_serial_number, part_number):
        #
        part = Part.objects(partNumber=part_number).first()
        #
        form = CommentForm(commentPartID=part.partID)
        #
        if request.method=='POST' and form.validate_on_submit():
            #
            comment = Comment(commentPartID=form.commentPartID.data, 
                    commentTitle=form.commentTitle.data,
                    commentContent=form.commentContent.data,
                    commentAuthor=form.commentAuthor.data,
                    commentCategory=form.commentCategory.data)
            comment.save()
            #
            #
            #* Obtain the images from request
            images = request.files.getlist('commentImage')
            for image in images:
                comment.update(add_to_set__commentImage=[image])
            #
            flash(f'Comment for part {part.partNumber} by {comment.commentAuthor} has been successfully saved.', 'success')
            #
            return redirect(url_for('main_blueprint.part', machine_serial_number=machine.machineSerialNumber, part_number=part.partNumber))
        #
        return render_template('create_comment.html', title='Create Comment', machine=machine, part=part, form=form)

表格.py

    class CommentForm(FlaskForm):
        commentPartID = HiddenField()
        #
        commentTitle = StringField('Title', validators=[DataRequired()])
        commentContent = TextAreaField('Content', validators=[DataRequired()])
        commentAuthor = StringField('Comment Author', validators=[DataRequired()])
        #
        commentImage = MultipleFileField('Image File', validators=[FileAllowed(['jpg', 'png'], 'Only image files may be uploaded!')])
        commentCategory = SelectField('Category')
        #
        submit = SubmitField('Save Comment')
        #

这给我带来了以下错误。

bson.errors.InvalidDocument: cannot encode object:<FileStorage: 'Screenshot (1).png' ('image/png')>, of type: <class 'werkzeug.datastructures.FileStorage'>

我目前的变通办法是：模型.py

    class Comment(Document):
        #
        meta = {'collection': 'comments'}
        #
        commentPartID = fields.StringField(required=True)
        #
        commentTitle = fields.StringField(required=True)
        commentContent = fields.StringField(required=True)
        commentInsertedAt = fields.DateTimeField(required=True, default=datetime.datetime.utcnow)
        commentAuthor = fields.StringField(required=True)
        #
        commentCategory = fields.StringField()
        commentTag = fields.StringField()
    #
    #
    class CommentImage(Document):
        meta = {'collection': 'images'}
        #
        imageCommentID = fields.ObjectIdField()
        imageContent = fields.ImageField(size=(1200,800,False), thumbnail_size=(300,200,False), collection_name='images')
        #

路由.py

    @comment_blueprint.route('/parts/<part_number>/add_comment', methods=['GET', 'POST'])
    def create_comment(machine_serial_number, part_number):
        #
        part = Part.objects(partNumber=part_number).first()
        #
        form = CommentForm(commentPartID=part.partID)
        #
        if request.method=='POST' and form.validate_on_submit():
            comment = Comment(commentPartID=form.commentPartID.data,  
                    commentProjectName=form.commentProjectName.data,
                    commentTitle=form.commentTitle.data,
                    commentContent=form.commentContent.data,
                    commentAuthor=form.commentAuthor.data,
                    commentCategory=form.commentCategory.data).save()
            #
            #* Obtain comment ID; this is needed for the CommentImage to establish a link to the Comment
            comment = Comment.objects().order_by('-commentInsertedAt').first()
            #
            #* Obtain the images from request
            images = request.files.getlist('commentImage')
            for image in images:
                image = CommentImage(imageCommentID=comment.id, imageContent = image)
                image.save()
            #
            flash(f'Comment for part {part.partNumber} by {comment.commentAuthor} has been successfully saved.', 'success')
            #
            return redirect(url_for('main_blueprint.part', machine_serial_number=machine.machineSerialNumber, part_number=part.partNumber))
        #
        return render_template('create_comment.html', title='Create Comment', machine=machine, part=part, form=form)

froms.py这一点一直没有改变。