Develop Reference

sqlite3 works well in centos7 and python shell,but can't work in Uwsgi

I have a question need your help~
I have a django program run in a vps(centos7,django2.2),it works well with Nginx+Uwsgi.
I edit three files(like a.py b.py c.py),and upload to the vps by winscp.exe,the program can't work now.
I found these logs in the uwsgi.log file.
File "/mnt/datasource/<privacy_hidden>/venv/lib/python3.6/site-packages/django/db/backends/sqlite3/base.py", line 68, in <module>
check_sqlite_version()
File "/mnt/datasource/<privacy_hidden>/venv/lib/python3.6/site-packages/django/db/backends/sqlite3/base.py", line 65, in check_sqlite_version
raise ImproperlyConfigured('SQLite 3.8.3 or later is required (found %s).' % Database.sqlite_version)
django.core.exceptions.ImproperlyConfigured: SQLite 3.8.3 or later is required (found 3.7.17).
unable to load app 0 (mountpoint='') (callable not found or import error)
I wrote "sqlite3 --version" in centos7 shell, it show version = 3.30.1
I wrote "python >>> import sqlite3 >>>print sqlite3.sqlite_version" it show version=3.30.1
I wrote "python manage.py runserver --noreload 0.0.0.0:80",it works well, no info show sqlite error.
But the program can't work in uwsgi,I think the uwsgi.ini is correct.
What can I do ?
Thank you!

I think I have solved this question.
In centos shell:
> mv /usr/lib64/libsqlite3.so.0.8.6 /usr/lib64/libsqlite3.so.0.8.6_old
> cp /usr/local/lib/libsqlite3.so.0.8.6 /usr/lib64/libsqlite3.so.0.8.6
then it's ok

uwsgi has RPATH set. and its' /usr/lib64, and the old sqlite library is in this directory, you need to use the newer sqlite library in /usr/local/lib.
you could recompile uwsgi like this: sudo LDFLAGS="-L/usr/local/lib -Wl,-rpath,/usr/local/lib" pip3 install uwsgi.
refrence: https://sourceexample.com/en/1c4153d4c3d4e65dac45/

"cannot load such file -- bundler/setup (LoadError)" on Heroku

I know there are a number of these questions, but none seem to solve my issue.
I'm running ruby SASS via django-pipelines.
During deployment, pipelines compiles some SASS files through the command python manage.py collectstatic --noinput which is done by Heroku automatically.
Previously I had no problems deploying this. I've recently come back to the code and now when I deploy to Heroku, I receive the following errors (full error log can be found here):
File "/app/.heroku/python/lib/python2.7/site-packages/pipeline/compilers/__init__.py", line 126, in execute_command
"{0!r} exit code {1}\n{2}".format(argument_list, compiling.returncode, stderr))
pipeline.exceptions.CompilerError: ['/usr/bin/env', 'sass', '--load-path', '/app/app/static', '--load-path', '/app/app2/static', u'/app/staticfiles/app2/stylesheets/app2.scss', u'/app/staticfiles/app2/stylesheets/app2.css'] exit code 1
/tmp/build_8d2e04464970e15667c8f825fc387c8a/myapp-8b763976868799a3f147ac8cedbd82421efa7525/vendor/ruby-2.2.2/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:54:in `require': cannot load such file -- bundler/setup (LoadError)
from /tmp/build_8d2e04464970e15667c8f825fc387c8a/myapp-8b763976868799a3f147ac8cedbd82421efa7525/vendor/ruby-2.2.2/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:54:in `require'
from /tmp/build_8d2e04464970e15667c8f825fc387c8a/myapp-8b763976868799a3f147ac8cedbd82421efa7525/vendor/bundle/bin/sass:14:in `<main>'
! Error while running '$ python manage.py collectstatic --noinput'.
As you can see, I've deployed using Ruby 2.2.2 previously, but now bundler has been updated on Heroku from 1.9.7 to 1.11.2.
Sass is the same version (3.4.19).
Line 14 of bin/sass from the last successful deployment on heroku.
$ sass --version
Sass 3.4.19 (Selective Steve)
$ cat ./vendor/bundle/bin/sass | sed '14!d'
require 'bundler/setup'
$ bundle --version
Bundler version 1.9.7
Curiously, the contents of my local version of bin/sass look nothing like the one on Heroku.
$ cat ~/.rvm/gems/ruby-2.2.2#app/bin/sass | sed '14!d'
str = ARGV.first
Locally, I'm running Ruby 2.2.2 and have tried both bundler 1.10.6 and 1.11.2.
Here is my Gemfile:
source 'https://rubygems.org'
ruby '2.2.2'
gem 'sass', '3.4.19'

I had the same problem as yours and found that the only solution was to switch out the SASS Compiler with Compass Compiler (installed with the django-pipeline-compass package). See Andrew's answer here: https://stackoverflow.com/a/31420009/6080975

'pyramid-debugtoolbar' distribution was not found and is required

I'm trying to debug my pyramid application via eclipse. I've followed the instructions in this link.
When I try to run my app, I get the following error:
pkg_resources.DistributionNotFound: The 'pyramid-debugtoolbar' distribution was not found and is required by..
I've un-commented the line in development.ini pyramid.includes = pyramid_debugtoolbar
What am I doing wrong?

You most forgot to run:
python setup.py develop
For your application so it didn't pull all the required dependancies.
pip install -e .
willl also work.

Python web application with OpenCV in Heroku

I am building a web application that uses OpenCV in its back-end. I have built the application on Ubuntu (and I tried it on Windows, too) and it works fine. Currently, I am trying to configure OpenCV to work on Heroku. As OpenCV is not possible to be loaded using pip, I read about using heroku buildpacks which provide customization for the server environment.
The following is my attempt to test two of OpenCV buildpacks:
I build simple web server with Flask that tries to import OpenCV:
#hello.py
import os
from flask import Flask
app = Flask(__name__)
#app.route("/")
def hello():
text = ''
try:
import cv2
text = 'success'
except:
text = 'fail'
pass
return text + ' to load openCV'
if __name__ == "__main__":
port = int(os.environ.get("PORT", 5000))
app.run(host='0.0.0.0', port=port)
The above code should return either success or fail in loading OpenCV.
Then I configured Heroku to use (heroku multi buildpack) by running the following command:
heroku buildpacks:set https://github.com/ddollar/heroku-buildpack-multi
In the .buildpacks file (that is required by multi buildpack) I put the https://github.com/heroku/heroku-buildpack-python and https://github.com/slobdell/heroku-buildpack-python-opencv-scipy buildpacks.
The first one is for compiling a python application and for installing other modules (e.g., Flask) through pip. The second buildpack is the one that is supposed to load OpenCV.
After all, the whole application did not work!
I got (Application Error) page in Heroku as following screenshot:
I tried to use other buildpack (https://github.com/diogojc/heroku-buildpack-python-opencv-scipy) but I got the same result.
My questions are:
What is wrong in the steps I did?
How should I call (or use) OpenCV within my application in heroku?Should I use import statement or some other commands?

I could install by doing as follows:
cd /path/to/your/dir && git init
heroku create MYAPP (start from scratch)
heroku config:add BUILDPACK_URL=https://github.com/ddollar/heroku-buildpack-multi.git --app MYAPP
create .buildpacks as follows:
https://github.com/heroku/heroku-buildpack-python
https://github.com/diogojc/heroku-buildpack-python-opencv-scipy#cedar14
git add . && git commit -m 'MESSAGE' && git push heroku master

For anyone seeing this today and having the same issue, switch opencv-python in your requirements.txt to opencv-python-headless. This sidesteps the problem with the problematic library file.

The following steps should solve the problem of openCV which you are facing -
Add the heroku-buildpack-apt to the BuildPack by pasting - https://github.com/heroku/heroku-buildpack-apt to add buildpack in dasboard.
ScreenShot -
Adding through Dashboard -> Settings -> Add BuildPacks
Then add the Aptfile in your Github base directory which contains -
libsm6
libxrender1
libfontconfig1
libice6
- one library in each line. See Example Github Link
Now build and deploy and you are ready to go!

Deploy pure python to heroku

I "finished" a little python project and I want to deploy it on heroku
GitHub page.
I want to execute: python2 main.py -i json-rpc
in order to have the json-rpc server listening for connections
but I get the following error when pushing to heroku:
$ git push heroku master Counting objects: 153, done. Delta
compression using up to 8 threads. Compressing objects: 100% (87/87),
done. Writing objects: 100% (153/153), 43.42 KiB, done. Total 153
(delta 61), reused 153 (delta 61)
-----> Heroku receiving push ! Heroku push rejected, no Cedar-supported app detected
To git#heroku.com:panager.git ! [remote rejected] master -> master
(pre-receive hook declined) error: failed to push some refs to
'git#heroku.com:panager.git'

What you might want to try doing is creating a Procfile. The full filename is Procfile, no extension, and it goes in the main directory of your project folder.
The content of that file would be:
web: python main.py -i json-rpc
Give that a shot and see if it works.
Alternatively, you may have forgotten to create a virtualenv for your app.
You should follow the instructions in Heroku's guide Getting Started with Python on Heroku
Update:
Having finally tested this myself on a fresh Heroku app, what you're missing is a requirements.txt. Even though you don't have any dependencies, you still need it. Within your virtualenv in the main project folder, run pip freeze > requirements.txt, and then git add . then git commit -m "added requirements.txt", and then push to Heroku and it should work.

Also, make sure that requirements.txt is saved with ANSI encoding, not Unicode or UTF-8! If you're a total n00b like me you can simply open requirements.txt in Notepad, choose SAVE AS and change the "Encoding" from the drop down. I tried all of the recommendations above but my error was due to this simple encoding problem.