Installation for SQLAlchemy Doesn't link to Flask - python-2.7

I am trying to install SQLAlchemy on a Windows 8 64 bit machine for Python 2.7
When I run the setup.py file that comes with the download from the SQLAlchemy site, a .egg file called 'SQLAlchemy-1.0.0-py2.7.egg' is placed in C:\Python27\Lib\site-packages.
But when I try to do a basic import of the library using an import statement on given in the SQLAlchemy documentation, I get an error message.
The import code is:
from flask.ext.sqlalchemy import SQLAlchemy
And the error message I get is:
c:\Users\Me\MyCode>ws_dbwrite.py
Traceback (most recent call last):
File "C:\Users\Me\MyCode\ws_dbwrite.py", line 2, in <module>
from flask.ext.sqlalchemy import SQLAlchemy
File "C:\Python27\lib\site-packages\flask-0.10.1-py2.7.egg\flask\exthook.py",
line 87, in load_module
raise ImportError('No module named %s' % fullname)
ImportError: No module named flask.ext.sqlalchemy
Should I be going about installation in a different manner? Or should the .egg file for SQLAlchemy go at a different file level? Or am I missing something obvious here?
Edit: If I change the import line to just
import SQLAlchemy
The import works, but Python does not recognize things like
db = SQLAlchemy(app)
as valid commands.

You have installed SQLAlchemy, but you are trying to use the Flask extension, Flask-SQLAlchemy. While the two are related, they are separate libraries. In order to use
from flask.ext.sqlalchemy import SQLAlchemy
you need to install it first.
pip install Flask-SQLAlchemy
(You installed SQLAlchemy directly from source. You can also do that for Flask-SQLAlchemy.)

Related

Unable to import models from the local python file

I have installed flask and flask-sqlalchemy in my base environment of the conda. I defined the models in separate file (model.py), when I am trying to import it in my app.py file it's throwing the following error
When you write from model import User, you cause python to import from app import db, i.e. import app into app, which is not allowed in python
Please, take a look at this answer, I wrote it pretty straightforward how to solve this problem with flask-sqlalchemy:
https://stackoverflow.com/a/62991785/10468419

ImportError: cannot import name cygrpc

I am trying to use Firebase Native mode on Google App Engine - Standard. My python language is Python 2.7. When I try to from google.cloud import firestore, I get an error ImportError: cannot import name cygrpc
I have deployed virtualenv described in the documentation here.
pip install virtualenv
virtualenv env
source env/bin/activate
My appengine_config.py is
from google.appengine.ext import vendor
import os.path
# Add any libraries installed in the "lib" folder.
vendor.add('lib')
vendor.add(os.path.join(os.path.dirname(os.path.realpath(__file__)), 'lib'))
my_app.py includes
from google.appengine.ext.webapp import template
from google.appengine.ext import ndb
from google.appengine.api import mail
import os
from google.cloud import firestore
(/base/alloc/tmpfs/dynamic_runtimes/python27g/43d5822312de17fd/python27/python27_lib/versions/1/google/appengine/runtime/wsgi.py:269)
Traceback (most recent call last):
File "/base/alloc/tmpfs/dynamic_runtimes/python27g/43d5822312de17fd/python27/python27_lib/versions/1/google/appengine/runtime/wsgi.py", line 240, in Handle
handler = _config_handle.add_wsgi_middleware(self._LoadHandler())
File "/base/alloc/tmpfs/dynamic_runtimes/python27g/43d5822312de17fd/python27/python27_lib/versions/1/google/appengine/runtime/wsgi.py", line 311, in _LoadHandler
handler, path, err = LoadObject(self._handler)
File "/base/alloc/tmpfs/dynamic_runtimes/python27g/43d5822312de17fd/python27/python27_lib/versions/1/google/appengine/runtime/wsgi.py", line 85, in LoadObject
obj = __import__(path[0])
File "/base/data/home/apps/s~openbarn-prod/20190602t102855.418624175446659791/main.py", line 4, in <module>
from controllers import server, common, header
File "/base/data/home/apps/s~openbarn-prod/20190602t102855.418624175446659791/controllers/server.py", line 10, in <module>
from google.cloud import firestore
File "/base/data/home/apps/s~openbarn-prod/20190602t102855.418624175446659791/lib/google/cloud/firestore.py", line 18, in <module>
from google.cloud.firestore_v1 import __version__
File "/base/data/home/apps/s~openbarn-prod/20190602t102855.418624175446659791/lib/google/cloud/firestore_v1/__init__.py", line 22, in <module>
from google.cloud.firestore_v1._helpers import GeoPoint
File "/base/data/home/apps/s~openbarn-prod/20190602t102855.418624175446659791/lib/google/cloud/firestore_v1/_helpers.py", line 21, in <module>
import grpc
File "/base/data/home/apps/s~openbarn-prod/20190602t102855.418624175446659791/lib/grpc/__init__.py", line 23, in <module>
from grpc._cython import cygrpc as _cygrpc
ImportError: cannot import name cygrpc
The question I have - can you use Firestore Native mode on Google App Engine Standard using Python 2.7? I need GAE- Standard because we are using Google Endpoint that is not support on GAE-Flex.
The doc here says App Engine Client library integration is not supported on Python2.7 GAE Standard environment. But I am not trying App Engine Client library, I am trying App Engine Server library in GAE Standard Environment.
How do I solve for import error for cygrpc? The solution here, says -
python -m pip install grpcio --ignore-installed
Is this recommended?
It's 2020, and you can now use grpcio (without explicitly adding it yourself as it's a built-in library) w/Cloud Firestore natively on App Engine with Python 2.7. Three things to make this work:
Add google-cloud-firestore to your requirements.txt file and install with pip install -U -t lib -r requirements.txt.
Add these lines to the libraries section of your app.yaml file:
libraries:
- name: grpcio
version: 1.0.0
- name: setuptools
version: 36.6.0
Ensure these lines are in your appengine_config.py file:
import pkg_resources
from google.appengine.ext import vendor
# Set path to your libraries folder.
path = 'lib'
# Add libraries installed in the path folder.
vendor.add(path)
# Add libraries to pkg_resources working set to find the distribution.
pkg_resources.working_set.add_entry(path)
Of course, we do recommend you eventually migrate to Python 3 to take advantage of the greater flexibility the next generations (of Python and App Engine) provide, esp. the ability to tap into other GCP services. However, caveat such a port isn't without effort if your app is complex & deeply-dependent on App Engine's 1st gen built-in services. Most of the suggestions above are derived from this section of the migration docs.
Once you're on Python 3, everything related to 3P libraries on App Engine becomes much easier, as I demonstrate in this other SO answer.
A while ago GRPC wasn't supported on GAE standard, see GRPC and types import error in App Engine Datastore. I didn't try since, but I don't see newer activity on issue 149.
Also the cython reference in the traceback suggests that it may include compiled code, which would violate the pure python standard environment sandbox restrictions that applies to the code you deploy.
Make sure that your installed python version bit(32/64) and your system bit(32/64) are matched.
If they are not matched please follow the solution mentioned at https://azurelessons.com/cannot-import-name-cygrpc/

Does django version 1.11 work with djongo package?

When I try to run the server using django==1.11 I get this error.
from djongo import models
File "/usr/local/lib/python3.6/dist-packages/djongo/models/__init__.py", line 3, in <module>
from .fields import (
File "/usr/local/lib/python3.6/dist-packages/djongo/models/fields.py", line 28, in <module>
from django.db.models.fields.mixins import FieldCacheMixin
ModuleNotFoundError: No module named 'django.db.models.fields.mixins'
But when I try doing the same using django==2 everything works fine.
Nothing regarding the Django version is given in the docs: https://nesdis.github.io/djongo/get-started/
The requirements.txt file in djongo on Github says it does support django==1.11.
sqlparse>=0.2.3
pymongo>=3.2.0
django>=1.11
Any help is appreciated.
The django.db.models.fields.mixins file is new in Django 2.0 (here is the commit where it was added).
If djongo imports this file, then it doesn't support Django 1.11.
So I found out what the issue was.Djongo package version==1.2.23 works with django==1.11

ImportError: No module named Selenium, any suggestions?

I am in the process of learning the RobotFramework from an absolute beginners point.
I have had experience creating automation scripts using ruby-watir and gherkin. As well as automation in c#.
However I am simply stumped with even the setup of RobotFramework in Pycharm.
I have installed all the packages
I deemed necessary
-including selenium/RobotFramework /RobotFramework-selenium2library.
My Python.exe and scripts are in the correct directory as well as the environment variables being added.
However when I run :
from lettuce import *
from behave import *
from Selenium import webdriver
#step("I am on the web")
def step_impl(context):
context.browser = webdriver.Firefox
pass
I get:
Traceback (most recent call last):
File "C:/Users/Jordan/PycharmProjects/RbtFrameWork/features/steps/Test_steps.py", line 3, in <module>
from Selenium import webdriver
ImportError: No module named Selenium
I imagine it's something to do with the installation location of my selenium - which I have installed through pip
Any help?
Python is case sensitive so instead of from Selenium import webdriver you should use from selenium import webdriver

Cannot import django.core

I am trying to setup django with fastcgi on apache. Django is installed and seems to be running correctly but I am having problems with setting up fastcgi.
I decided to test out my dispatch.fcgi script in the interactive python shell line by line and the following line:
from django.core.servers.fastcgi import runfastcgi
results in the following error:
ImportError: No module named core.servers.fastcgi
I can import django with no problem but import django.core gives yet another ImportError (No module named core).
How can I go about ensuring that I can import django.core. If I can import django then in must be on my path, and so why can I not import core?
You probably have a file/folder called django somewhere in your path, that isn't the actual path.
try this
import sys
sys.path
And then check everything in that output to see if there is a file/folder called django(.py) somewhere.
If so, change the path (sys.path = ['/path/to/directory/below/django/install'] + sys.path) or move/rename the file.
Probably you have django.py module in your working directory or in any other that is in python path.
For anyone having this problem and coming across this question like I did, it turns out that fastcgi support has been removed as of Django 1.9, thus you will get this import error if trying to import it. Refer Using Django with virtualenv, get error ImportError: No module named 'django.core.servers.fastcgi'