Gatsby製作Blog

https://www.gatsbyjs.org/docs/adding-a-list-of-markdown-blog-posts/
https://codinghero.netlify.com/

定時排程刪除超過一定天數的檔案

https://softwareengineering.stackexchange.com/questions/149824/automatically-delete-files-after-they-expire
https://superuser.com/questions/1072679/bash-what-does-means
http://linux.vbird.org/linux_basic/0430cron.php

find $search_path -atime +3 -exec rm {} \;

加到crontab裡面
# crontab -e

{}的意思就是find輸出的結果會帶到rm的參數，\;是確保command結束符號，可用+取代

pyenv-win 安裝與移除

https://github.com/pyenv-win/pyenv-win

1. Install
pip install pyenv-win --target %USERPROFILE%/.pyenv

2. Add following to PATH enviroment variable
%USERPROFILE%\.pyenv\pyenv-win\bin;%USERPROFILE%\.pyenv\pyenv-win\shims;

3. Add installed path in file easy_install.pth to site-packages folder(ex: C:\Users\Jack_Lin\AppData\Local\Programs\Python\Python37-32\Lib\site-packages).
Need to add absolute path, ex:
C:\Users\Jack_Lin\.pyenv in file easy_install.pth

4. pip list to check pyenv-win is installed and recognize by pip

5. upgrade
pip install --upgrade pyenv-win

6. uninstall
pip uninstall pyenv-win

如何push本地branch並覆蓋remote branch

git push -f --set-upstream origin master
git push -f  要小心使用

Scrapy學習筆記

若要整合Django和Scrapy，可利用DjangoItem，可節省定義Item的部分，讓Scrapy的Item定義自動去參照Django model，也可在Item增加欄位。

ItemLoader的部分，預設add_value後，postprocessor都會以list為最後輸出結果，可更感post processor為TakeFirst。

在Pipeline裡，若應用到DjangoItem，要先save後，在以Django model來操作 Foreign Key或是ManyToManyField部分。DjangoItem無法直接取得Django model內容。DjangoItem只是取去參考Django model，省去寫 field_xxx = scrapy.Field()而已。

pandas Dataframe操作

import pandas as pd
df = pd.read_excel('b.xlsx', 'Acceptance')
df[df['Config 3'].notna()]

裡面的df['Config 3'].notna()是filter的方式，結果是列出所有Config13欄位不是na的 rows

Pandas的Series是縱向的，例如某個Column的值的列表

pandas兩個主要的data structure
DataFrame和Series
DataFrame就是Series的容器
Series就是純量的容器

Indexing / Selection

The basics of indexing are as follows:

Operation	Syntax	Result
Select column	df[col]	Series
Select row by label	df.loc[label]	Series
Select row by integer location	df.iloc[loc]	Series
Slice rows	df[5:10]	DataFrame
Select rows by boolean vector	df[bool_vec]	DataFrame

如果要一個row一個row去做動作

https://stackoverflow.com/questions/16476924/how-to-iterate-over-rows-in-a-dataframe-in-pandas

df.iterrows()

inotify-tools監測資料夾

https://www.howtogeek.com/405468/how-to-perform-a-task-when-a-new-file-is-added-to-a-directory-in-linux/amp/

Delopy Django project on Ubuntu 1804 with mod_wsgi

1. Install apache2 & postgresql
2. Install mod_wsgi
# sudo apt install libapache2-mod-wsgi-py3
3. Create a Python3 virtualenv
# mkvirtualenv -p $(which python3) django & psycopg2-binary
(django)# pip install django
(django)# pip install psycopg2-binary
4. Enter into project folder. /home/jack/Documents/Projects/myproject
5. Install Requirement python package
(django) # pip install -r requirements.txt
6. Note that the wsgi.py is put on /home/jack/Documents/Projects/myproject/myproject
7. Edit settings.py in ./myproject
Add ALLOWED_HOSTS = ['*',]
(This is risky)
Add STATIC_ROOT = '/home/jack/Documents/Projects/myproject/static'
8. Setup Postgresql database correctly & create a database in it.
9. Edit settings.py to meet the database you want to use.
10. Database Migrate & collectstatic
(django) # python manage.py migrate
(django) # python manage.py collectstatic
11. create a new conf in /etc/apache2/site-available myproject.conf with sudo

    ServerName myproject
    Alias /robots.txt /home/jack/Documents/Projects/myproject/static/static/robots.txt
    Alias /favicon.ico /home/jack/Documents/Projects/myproject/static/favicon.ico
    Alias /static/ /home/jack/Documents/Projects/myproject/static/
   
        Require all granted
   
    WSGIDaemonProcess django python-home=/home/jack/.virtualenvs/django/ python-path=/home/jack/Documents/Projects/myproject/
    WSGIScriptAlias / /home/jack/Documents/Projects/myproject/myproject/wsgi.py
    WSGIProcessGroup django
   
       
        Require all granted
       
   

12. Edit /etc/apache2/ports.conf, Add a line

Listen 4002

13. Enable the site & reload

# sudo a2ensite myproject

# sudo systemctl reload apache2

14. Allow port 4002 in Firewall

# sudo ufw allow 4002

Reference:
https://docs.djangoproject.com/en/2.1/howto/deployment/wsgi/
https://docs.djangoproject.com/en/2.1/howto/deployment/checklist/