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7 comentario(s)

Benji Martinez

01 Junio 21

3
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Hola a todos compañeros de código facilito, les comento que yo igual tuve el problema con el evento listen en donde no podia crear los registros porque según no estaba la tabla y salia el error " sqlalchemy.exc.ProgrammingError: (psycopg2.errors.UndefinedTable) relation "data" does not exist ", lo que hice para resolver este conflicto fue lo siguiente:

1. Borrar el entorno virtual que tenia todas las dependencias mas actuales ( las cuales supongo no son compatibles con eventos como listen )
2. Crear un entorno virtual de cero 
3.  En la raiz del proyecto es decir al nivel de main.py y config.py cree el archivo requirements.txt como se puede ver en esta liga del proyecto que proporciono el profesor Eduardo : https://github.com/codigofacilito/taller-api-flask
4. Agreguen al archivo esta linea en donde quieran: psycopg2==2.8.6
5. Instalamos las dependencias usadas en este curso con: pip install -r requirements.txt (con el entorno virtual activo)
6. Si todo va bien solo bastara ejecutar con el entorno vitual activo nuestro script con python main.py y listo
Espero les funcione a todos pues fue lo que me funciono a mi, saludos y a seguir aprendiendo :)


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Cutberto Uriel Paredes Hernandez

04 Abril 23

3
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Para solucionar el error de que la tabla no existe hay que quitar db.session.commit() del archivo task.py y ponerlo en app__init__.py después de db.create_all().

Queda así:

with app.app_context():
db.init_app(app)
db.create_all()
db.session.commit()

El problema con la versión del video es que está haciendo commit antes que se cree la tabla en base de datos.

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Juander Martin Contreras de Jesus

29 Abril 21

1
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sqlalchemy.exc.ProgrammingError: (psycopg2.errors.UndefinedTable) relation "data" does not exist

Creo que este error se deberia explicar, porque solo veo comentarios al respecto del mismo. 

Cuando utilizo el listen para ejecutar la funcion luego de haberse creado la base de datos, siempre me devuelve un error, pero cuando lo comento la base de datos se crea normalmente, pero incluso habiendo creado la base de datos manuelmente me dice que no existe.
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Juanma Lobato

26 Marzo 21

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Buenas tardes,

creo que el listen se ejecuta pero no me ha creado la tabla.
listen(Task.__table__, 'after_create', insert_tasks) 
    
Me da el error siguiente :

    cur.execute(b''.join(parts))
sqlalchemy.exc.ProgrammingError: (psycopg2.errors.UndefinedTable) no existe la relación «tasks»
LINE 1: INSERT INTO tasks (title, description, deadline, created_at)...
                    ^

[SQL: INSERT INTO tasks (title, description, deadline, created_at) VALUES (%(title)s, %(description)s, %(deadline)s, CURRENT_TIMESTAMP) RETURNING tasks.id]
[parameters: ({'title': 'Title 1', 'description': 'Description', 'deadline': '2019-12-12 12:00:00'}, {'title': 'Title 2', 'description': 'Description', 'deadline': '2019-12-12 12:00:00'})]
(Background on this error at: http://sqlalche.me/e/14/f405)

Alguna ayuda?

Saludos.
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Ariel Gavegno

26 Marzo 21

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Ayuda por favor con este error: listen(Task.table, 'after_create', insert_tasks)
ERROR: TypeError: insert_tasks() got an unexpected keyword argument 'checkfirst'

def insert_tasks():
    db.session.add(
        Task(title='Title 1', description='desc 1', deadline='2021-03-25 12:00:00')
    )
    db.session.add(
        Task(title='Title 2', description='desc 2', deadline='2021-03-25 12:00:00')
    )
    db.session.commit()

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Ricardo Lozano

24 Marzo 21

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Traceback (most recent call last):
  File "/Users/rdx/api_flask/api/main.py", line 7, in <module>
    app = create_app(enviroment)
  File "/Users/rdx/api_flask/api/app/init.py", line 18, in create_app
    db.create_all()
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/flask_sqlalchemy/init.py", line 1039, in create_all
    self.execute_for_all_tables(app, bind, 'create_all')
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/flask_sqlalchemy/__init_.py", line 1031, in execute_for_all_tables
    op(bind=self.get_engine(app, bind), *extra)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/sql/schema.py", line 4741, in create_all
    bind._run_ddl_visitor(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/engine/base.py", line 2979, in _run_ddl_visitor
    conn._run_ddl_visitor(visitorcallable, element, *kwargs)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/engine/base.py", line 2016, in run_ddl_visitor
    visitorcallable(self.dialect, self, *kwargs).traverse_single(element)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/sql/visitors.py", line 483, in traverse_single
    return meth(obj, *kw)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/sql/ddl.py", line 846, in visit_metadata
    self.traverse_single(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/sql/visitors.py", line 483, in traverse_single
    return meth(obj, **kw)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/sql/ddl.py", line 912, in visit_table
    table.dispatch.after_create(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/event/attr.py", line 320, in __call
    fn(args, *kw)
  File "/Users/rdx/api_flask/api/app/models/task.py", line 27, in insert_tasks
    Task(title='Title 1',description='Description',deadline='2019-12-12 12:00:00',default='2021-03-24 18:58:21')
  File "<string>", line 4, in init
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/orm/state.py", line 437, in initialize_instance
    manager.dispatch.init_failure(self, args, kwargs)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/util/langhelpers.py", line 70, in __exit_
    compat.raise_(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/util/compat.py", line 198, in raise_
    raise exception
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/orm/state.py", line 434, in _initialize_instance
    return manager.original_init(mixed[1:], *kwargs)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/orm/decl_base.py", line 1083, in _declarative_constructor
    raise TypeError(
TypeError: 'default' is an invalid keyword argument for Task
(env) MacBook-Pro-de-Ricardo:api rdx$ python main.py
Traceback (most recent call last):
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/engine/base.py", line 1685, in _execute_context
    self.dialect.do_executemany(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/dialects/postgresql/psycopg2.py", line 881, in do_executemany
    context._psycopg2_fetched_rows = xtras.execute_values(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/psycopg2/extras.py", line 1292, in execute_values
    cur.execute(b''.join(parts))
psycopg2.errors.UndefinedTable: relation "tasks" does not exist
LINE 1: INSERT INTO tasks (title, description, deadline, created_at)...
                    ^



The above exception was the direct cause of the following exception:



Traceback (most recent call last):
  File "/Users/rdx/api_flask/api/main.py", line 7, in <module>
    app = create_app(enviroment)
  File "/Users/rdx/api_flask/api/app/init.py", line 18, in create_app
    db.create_all()
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/flask_sqlalchemy/init.py", line 1039, in create_all
    self.execute_for_all_tables(app, bind, 'create_all')
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/flask_sqlalchemy/__init_.py", line 1031, in execute_for_all_tables
    op(bind=self.get_engine(app, bind), *extra)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/sql/schema.py", line 4741, in create_all
    bind._run_ddl_visitor(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/engine/base.py", line 2979, in _run_ddl_visitor
    conn._run_ddl_visitor(visitorcallable, element, *kwargs)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/engine/base.py", line 2016, in run_ddl_visitor
    visitorcallable(self.dialect, self, *kwargs).traverse_single(element)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/sql/visitors.py", line 483, in traverse_single
    return meth(obj, *kw)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/sql/ddl.py", line 846, in visit_metadata
    self.traverse_single(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/sql/visitors.py", line 483, in traverse_single
    return meth(obj, **kw)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/sql/ddl.py", line 912, in visit_table
    table.dispatch.after_create(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/event/attr.py", line 320, in __call
    fn(args, *kw)
  File "/Users/rdx/api_flask/api/app/models/task.py", line 34, in insert_tasks
    db.session.commit()
  File "<string>", line 2, in commit
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/orm/session.py", line 1406, in commit
    self.transaction.commit(to_root=self.future)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/orm/session.py", line 820, in commit
    self._prepare_impl()
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/orm/session.py", line 799, in _prepare_impl
    self.session.flush()
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/orm/session.py", line 3224, in flush
    self._flush(objects)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/orm/session.py", line 3364, in _flush
    transaction.rollback(_capture_exception=True)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/util/langhelpers.py", line 70, in __exit
    compat.raise_(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/util/compat.py", line 198, in raise_
    raise exception
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/orm/session.py", line 3324, in flush
    flush_context.execute()
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/orm/unitofwork.py", line 453, in execute
    rec.execute(self)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/orm/unitofwork.py", line 627, in execute
    util.preloaded.orm_persistence.save_obj(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/orm/persistence.py", line 242, in save_obj
    _emit_insert_statements(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/orm/persistence.py", line 1153, in _emit_insert_statements
    c = connection._execute_20(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/engine/base.py", line 1520, in _execute_20
    return meth(self, args_10style, kwargs_10style, execution_options)
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/sql/elements.py", line 313, in _execute_on_connection
    return connection._execute_clauseelement(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/engine/base.py", line 1389, in _execute_clauseelement
    ret = self._execute_context(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/engine/base.py", line 1748, in _execute_context
    self._handle_dbapi_exception(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/engine/base.py", line 1929, in _handle_dbapi_exception
    util.raise(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/util/compat.py", line 198, in raise_
    raise exception
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/engine/base.py", line 1685, in _execute_context
    self.dialect.do_executemany(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/sqlalchemy/dialects/postgresql/psycopg2.py", line 881, in do_executemany
    context._psycopg2_fetched_rows = xtras.execute_values(
  File "/Users/rdx/api_flask/env/lib/python3.9/site-packages/psycopg2/extras.py", line 1292, in execute_values
    cur.execute(b''.join(parts))
sqlalchemy.exc.ProgrammingError: (psycopg2.errors.UndefinedTable) relation "tasks" does not exist
LINE 1: INSERT INTO tasks (title, description, deadline, created_at)...
                    ^



[SQL: INSERT INTO tasks (title, description, deadline, created_at) VALUES (%(title)s, %(description)s, %(deadline)s, %(created_at)s) RETURNING tasks.id]
parameters: ({'title': 'Title 1', 'description': 'Description', 'deadline': '2019-12-12 12:00:00', 'created_at': '2021-03-24 18:58:21'}, {'title': 'Title 2', 'description': 'Description', 'deadline': '2019-12-12 12:00:00', 'created_at': '2021-03-24 18:58:21'})

Ricardo Lozano

24 Marzo 21

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Buenas tardes :
Me marca un error cuando ejecuto el callback
listen(Task.__table__,'after_create',insert_tasks)
No crea la base de datos , y por lo tanto falla el insert .  Pero cuando comento la parte del listen , si crea la base de datos , y no me marca error .
Les adjunto la respuesta completa , espero me puedan ayudar , de antemano muchas gracias , saludos .
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Clase 8

Insertar registros

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