リストデータを持つマシュマロネストされたスキーマを理解する

Question

Pythonには新しく、marshmallowシリアライゼーションを使用しています。入れ子にされたscehmaを使用することができません。私のコードで間違っ 、私のコード

from sqlalchemy import Column, Float, Integer, String, Text, text,ForeignKey 
from sqlalchemy.ext.declarative import declarative_base 
from sqlalchemy.orm import relationship 

Base = declarative_base() 
metadata = Base.metadata 




class CompanyDemo(Base): 
    __tablename__ = 'company_demo' 

    company_id = Column(Integer, primary_key=True,              
    server_default=text("nextval('company_demo_company_id_seq'::regclass)")) 
    name = Column(Text, nullable=False) 
    address = Column(String(50)) 
    location = Column(String(50)) 


class UsersDemo(Base): 
    __tablename__ = 'users_demo' 

    id = Column(Integer, primary_key=True,                              
    server_default=text("nextval('users_demo_id_seq'::regclass)")) 
    company_id = Column(Integer,ForeignKey('company_demo.company_id'), nullable=False) 
    email = Column(String) 

company = relationship('CompanyDemo') 

スキーマ

from marshmallow import Schema, fields, pprint 


    class CompanySchema(Schema): 
     company_id = fields.Int(dump_only=True) 
     name = fields.Str() 
     address = fields.Str() 
     location = fields.Str() 


    class UserSchema(Schema): 
     email = fields.Str() 
     company = fields.Nested(CompanySchema) 


    user = UserSchema() 
    user = UserSchema(many=True) 
    company = CompanySchema() 
    company = CompanySchema(many=True) 

と私のフラスコアプリ

from flask import Flask, jsonify, url_for, render_template 
    from sqlalchemy import create_engine 
    from sqlalchemy.orm import sessionmaker 
    from flask_sqlalchemy import SQLAlchemy 
    from model import CompanyDemo, UsersDemo 
    from schemas.userschema import user, company 

    app = Flask(__name__) 
    app.secret_key = "shiva" 


    def db_connect(): 
     engine = create_engine('postgresql://ss@127.0.0.1:5432/test') 
     Session = sessionmaker(autocommit=False, autoflush=False, bind=engine) 
     # create a Session 
     session = Session() 
     session._model_changes = {} 
     return session 


    @app.route('/company', methods=["GET", "POST"]) 
    def get_all_company(): 
     db = db_connect() 
     allcompany = db.query(CompanyDemo).join(UsersDemo).all() 
     return jsonify(company.dump(allcompany, many=True).data) # company is marshmallow schema 


    if __name__ == '__main__': 
     app.run(host='0.0.0.0', port=15418, debug=True) 

何？ネストされたスキーマの問題に直面しており、出力にネストされたデータを取得できません。

下記出力[{ "アドレス"： "QQQ"、 "のcompany_id"：1、 "場所"： "WWW"、 "名前"： "EEE"}、 { "アドレス"： "WWW"、 "のcompany_id"：2、 "場所"： "QQQ"、 "名前"： "AAA"}]

Answer 1

自己のメモリ内のSQLiteを用いた例が含まれてい：

from flask import Flask, jsonify 
from flask.ext.sqlalchemy import SQLAlchemy 
from marshmallow import Schema, fields, pprint 

app = Flask(__name__) 
app.config['DEBUG'] = True 
app.config['SECRET_KEY'] = 'super-secret' 
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///:memory:' 
app.config['SQLALCHEMY_ECHO'] = True 
db = SQLAlchemy(app) 


class CompanyDemo(db.Model): 
    __tablename__ = 'company_demo' 

    company_id = db.Column(db.Integer, primary_key=True) 
    name = db.Column(db.Text, nullable=False) 
    address = db.Column(db.String(50)) 
    location = db.Column(db.String(50)) 

    def __unicode__(self): 
     return u"{name} ({address})".format(name=self.name, address=self.address) 


class UsersDemo(db.Model): 
    __tablename__ = 'users_demo' 

    id = db.Column(db.Integer, primary_key=True,) 
    company_id = db.Column(db.Integer, db.ForeignKey('company_demo.company_id'), nullable=False) 
    company = db.relationship('CompanyDemo') 
    email = db.Column(db.String) 

    def __unicode__(self): 
     return u"{email}".format(email=self.email) 


class CompanySchema(Schema): 
    company_id = fields.Int(dump_only=True) 
    name = fields.Str() 
    address = fields.Str() 
    location = fields.Str() 


class UserSchema(Schema): 
    email = fields.Str() 
    company = fields.Nested(CompanySchema) 

user_schema = UserSchema() 
company_schema = CompanySchema() 


@app.route('/') 
def index(): 
    return "<a href='/dump_company'>Dump Company</a><br><a href='/dump_user'>Dump User</a>" 

@app.route('/dump_user') 
def dump_user(): 
    user = UsersDemo.query.first() 
    return jsonify(user_schema.dump(user).data) 

@app.route('/dump_company') 
def dump_company(): 
    company = CompanyDemo.query.first() 
    return jsonify(company_schema.dump(company).data) 


def build_db(): 
    db.drop_all() 
    db.create_all() 
    company = CompanyDemo(name='Test 1', address='10 Downing Street', location='wherever') 
    db.session.add(company) 
    user = UsersDemo(email='fred@example.com', company=company) 
    db.session.add(user) 
    db.session.commit() 


@app.before_first_request 
def first_request(): 
    build_db() 

if __name__ == '__main__': 
    app.run(debug=True, port=7777)