Flask-SqlAlchemy - Relationship failed to locate a name - Please Help

[howardrwb]

Hi all,

I'm trying to connect to an existing sharepoint database (read only,) and
I'm getting the following error when I try to set up a many2many relationship between users and groups:

sqlalchemy.exc.InvalidRequestError: When initializing mapper mapped class 
SPT_group->Groups, expression 
'and_(SPT_group.site_id == SPT_group_member.c.SiteId, SPT_group.id == SPT_group_member.c.GroupId)' 
failed to locate a name ("name 'SPT_group_member' is not defined"). 
If this is a class name, consider adding this relationship() to the 
<class 'app.sharepoint.models.SPT_group'> class after both dependent classes have been defined.

I'm trying to follow this basic structure, but I have my models seperated out in directories as Blueprints.
https://blog.miguelgrinberg.com/post/the...-structure
We plan on using this as a "glue" app between lots of different systems, so the idea is to have all seperate blueprints. I'm pretty sure I don't understand how to properly deal with imports. Please Help.

I have tried putting the following in both app/__init__.py and app/sharepoint/__init__.py
"from app.sharepoint import models"
I have also tried putting this in both __init__.p files
"from app.sharepoint.models import SPT_group_member, SPT_user, SPT_group"
Nothing seems to work.

My Structure:

MyApp
|_app
  |___init__.py
  |_main
    |___init__.py
    |_routes.py
  |_sharepoint
    |___init__.py
    |_models.py
    |_routes.py
    |_forms.py
  |_security
    |___init__.py
    |_models.py
    |_routes.py
    |_forms.py
    ...

----
my app/__init__.py

from flask import Flask, request, current_app
from flask_sqlalchemy import SQLAlchemy
db = SQLAlchemy()
...

def create_app(config_class=Config):
    app = Flask(__name__)
    app.config.from_object(config_class)
    db.init_app(app)
	...

    from app.main import bp as main_bp
    app.register_blueprint(main_bp)

    from app.sharepoint import bp as sharepoint_bp
    app.register_blueprint(sharepoint_bp, url_prefix='/sharepoint')
	
    from app.security import bp as security_bp
    app.register_blueprint(security_bp, url_prefix='/security')
	

    return app

----
my app/sharepoint/__init__.py

from flask import Blueprint
bp = Blueprint('sharepoint', __name__)
from app.sharepoint import models, routes, forms

----
my app/sharepoint/models.py

SPT_group_member = db.Table('GroupMembership', db.Model.metadata,
    db.Column('SiteId', db.String(128), db.ForeignKey('dbo.Groups.SiteId'), primary_key=True),
    db.Column('GroupId', db.Integer(), db.ForeignKey('dbo.Groups.ID'), primary_key=True),
    db.Column('MemberId', db.Integer(), db.ForeignKey('dbo.UserInfo.tp_ID'), primary_key=True),
    info={'bind_key': 'sharepoint', 'table_args': {'schema': 'dbo'}}
)


class SPT_user(db.Model): #db.Model.metadata
    __tablename__ = 'UserInfo'
    __table_args__ = {'schema': 'dbo'}
    __bind_key__ = 'sharepoint'

    site_id = db.Column('tp_SiteID', db.String(128),  primary_key=True)
    user_id = db.Column('tp_ID', db.Integer(), primary_key=True)

    tp_DomainGroup = db.Column(db.Boolean())
    tp_Deleted = db.Column(db.Integer())
    tp_SiteAdmin = db.Column(db.Boolean())
    tp_IsActive = db.Column(db.Boolean())
    tp_Login = db.Column(db.String(255))
    tp_Title = db.Column(db.String(255))
    tp_Email = db.Column(db.String(255))
    tp_Notes = db.Column(db.String(1023))
    tp_Locale = db.Column(db.Integer())
    tp_CalendarType = db.Column(db.Integer())
    tp_AdjustHijriDays = db.Column(db.Integer())
    tp_TimeZone = db.Column(db.Integer())
    tp_Time24 = db.Column(db.Boolean())
    tp_AltCalendarType = db.Column(db.Integer())
    tp_CalendarViewOptions = db.Column(db.Integer())
    tp_WorkDays = db.Column(db.Integer())
    tp_WorkDayStartHour = db.Column(db.Integer())
    tp_WorkDayEndHour = db.Column(db.Integer())
    tp_Mobile = db.Column(db.String(127))
    tp_Flags = db.Column(db.Integer())
    tp_ExternalTokenLastUpdated = db.Column(db.DateTime(timezone=True))

    def __repr__(self):
        return "<SPT_user(site_id='%s', user_id='%s')>" % (self.site_id, self.user_id)



class SPT_group(db.Model):
    __tablename__ = 'Groups'
    __table_args__ = {'schema': 'dbo'}
    __bind_key__ = 'sharepoint'
    
    site_id = db.Column('SiteId', db.String(128),  primary_key=True)
    id = db.Column('ID', db.String(128),  primary_key=True)

    members = db.relationship(SPT_user, secondary=SPT_group_member, 
                    primaryjoin="and_(SPT_group.site_id == SPT_group_member.c.SiteId, "
                    					"SPT_group.id == SPT_group_member.c.GroupId)",
                    secondaryjoin="and_(SPT_group_member.c.SiteId == SPT_user.site_id,"
                   					"SPT_group_member.c.MemberId == SPT_user.user_id)",
                    backref=db.backref('groups', lazy='dynamic'), 
                    lazy='dynamic'
    )

    title = db.Column(db.String(255))
    description = db.Column(db.String(512))
    owner = db.Column(db.Integer())
    ownerIsUser = db.Column(db.Boolean())
    dLAlias = db.Column(db.String(128))
    dLErrorMessage = db.Column(db.String(512))
    dLFlags = db.Column(db.Integer())
    dLJobId = db.Column(db.Integer())
    dLArchives = db.Column(db.VARCHAR)
    requestEmail = db.Column(db.String(255))
    flags = db.Column(db.Integer())

    def __repr__(self):
        return "<SPT_group(site_id='%s', id='%s')>" % (self.site_id, self.id)