平時導出依賴一般都是 pip freeze > requirements.txt
這種方式導出的是當前python環境中所有的包，只會多不會少，有些庫不是必需的也跟着導出來，冗余過重。
這個時候 pipreqs 這個庫就派上用場了，它只會導出當前項目運行所依賴的包，環境中多余的庫就不會導出，在遷移環境時候很少方便。
pip install pipreqs
使用的時候也很簡單，進入項目的根目錄
pipreqs ./
等待一會就會生成一個requirements.txt文件
D:\PyPt\2018\ElasticSearch_New>pipreqs ./ Traceback (most recent call last): File "d:\anaconda3\lib\runpy.py", line 193, in _run_module_as_main "__main__", mod_spec) File "d:\anaconda3\lib\runpy.py", line 85, in _run_code exec(code, run_globals) File "D:\Anaconda3\Scripts\pipreqs.exe\__main__.py", line 9, in <module> File "d:\anaconda3\lib\site-packages\pipreqs\pipreqs.py", line 396, in main init(args) File "d:\anaconda3\lib\site-packages\pipreqs\pipreqs.py", line 341, in init extra_ignore_dirs=extra_ignore_dirs) File "d:\anaconda3\lib\site-packages\pipreqs\pipreqs.py", line 75, in get_all_ imports contents = f.read() UnicodeDecodeError: 'gbk' codec can't decode byte 0x8d in position 232: illegal multibyte sequence
報錯的時候需要調整下文件編碼 直接修改pipreqs.py 的75行，將encoding改為'utf-8'
D:\PyPt\2018\ElasticSearch_New>pipreqs ./ INFO: Successfully saved requirements file in ./requirements.txt D:\PyPt\2018\ElasticSearch_New>