Keep the color prompt in tmux
To keep your prompt (PS1) with color shown in tmux screen, add the following property in .bashrc : force_color_prompt=yes
Posts
Create docker container with the simple flask application
I will try to create a docker container with the simple flask application created some times ago. First, I create a shell script for starting the flask application, namely "boot.sh": boot.sh #!/bin/sh export FLASK_APP=simple.py flask run --host 0.0.0.0 Second, we need to create a requirements.txt file: requirements.txt flask == 1.1.1 Actually you can run the following to get the requirements.txt: pip freeze > requirements.txt Third, together with the simple.py file created in the simple flask application , put those 3 files in an "app" directory: app/ - boot.sh - requirements.txt - simple.py Forth, create a Docker file outside the app directory: Dockerfile FROM python:3.6-alpine WORKDIR /home/app COPY app/ ./ RUN chmod +x ./boot.sh RUN pip install -r requirements.txt EXPOSE 5000 ENTRYPOINT [ "./boot.sh" ] Buil...
Simple Flask sample
Just wanna to create a very simple Flask application in a single python source file: simple.py from flask import Flask application = Flask( "simple" ) @application.route ( "/" ) def index (): return "Hello World" To run this Flask application, run the following: export FLASK_APP=simple.py flask run If you want to put this application in a Docker container, you need to bind to 0.0.0.0: flask run --host 0.0.0.0 Now, navigate "http://localhost:5000" to see the word "Hello World" displayed on the browser.
Navigate tmux splitted pane using mouse
To enable navigation on tmux splitted pane using mouse In tmux environment, do the following: Ctrl-b Type :setw -g mouse on Done, try to switch your tmux pane with mouse. Note: To make this setting persistent, save this line in .tmux.conf : setw -g mouse on
Assign locale for moment.js
To assign locale in moment.js, we can use the following: moment.locale("en") It will returns "en". However, if you assign an unaccepted locale to it, it won't update its value. For example: moment.locale("zh") It still returns "en", since "zh" is not an accepted locale for moment.js. Up till now, moment.js accepts: zh-hk zh-tw zh-cn Reference: momentjs
QGIS freezes while editing features
There are many possibilities for QGIS to hang / freezes while editing features. But for my experience, I found it often hangs when using a Shapefile layer. To minimize this kind of problem, I tried to use other feature format (e.g. SpatialLite). And the problem is relieved to some extent. Have a try and let me know if it helps or not.
Windows equivalent of "wc -l" command in Linux
To count the number lines of files / stdout in Linux, we uses "wc -l" to achieve. In Windows, we use the following instead: find /c /v "" For example, suppose we have a file "sample_file.txt" and we want to know the number of lines of that file, we can perform the following: type sample_file.txt | find /c /v ""
Handling table names with underscore ("_") in flask_sqlalchemy / Python
When you create table class using flask_sqlalchemy (the Flask extension for SQLAlchemy), it can maps the modal class to a proper table automatically. This is cool but if you have a table name with underscore (e.g. MY_SAMPLE_TABLE) and you name your model class with the underscore ('_') as usual, you will find SQLAlchemy will map your table name as something the following: "MY__SAMPLE__TABLE" Each single underscore (_) with becomes a double underscores (__). This is annoying and you might believe this is a bug, but in fact you can resolve this issues by naming your table class using the PEP8 naming convention, and named your class as: class MySampleTable(db.Model): field_id = db.Column(db.Integer, primary_key = True) field_data = db.Column(db.String(200)) The the SQLAlchemy will map the MySampleTable class to table name as "MY_SAMPLE_TABLE" correctly. For more information about PEP8, click here for details.
