A simple tutorial on how to host a python service on a server using bat script and task scheduler.

Automatic start method

There are two major steps to achieve this. 1: Write a .bat file; 2. Set up windows task scheduler

Step1: Prepare Bat File

Following examples with virtual environment created by anaconda, with python installed under virtual environment.

1.1 identify virtual enviroment dir

Open anaconda prompt, and type: conda env list, to view the virtual environment names and pathes.

1.2 identify the path of activate.bat in virtual envoriment.

In windows, it is usually under env_dir\Lib\venv\scripts\nt. In Linux system, this file is usually under env_dir\Scripts.

1.3 identify python path

python where

1.4 Set up Bat Script

We here provide a sample Bat Script foo.bat to help you set up.

REM reset path and activate the virtual environment 
set original_dir = %CD%
REM os
set venv_root_dir= "virtual env path from 1.1\Lib\venv\scripts\nt"
cd %venv_root_dir%
call %venv_root_dir%\activate.bat

REM run python under the virtual environment 
Path_to_anaconda\Anaconda3\envs\virtual_env_name\python.exe 

Since windows cannot automatically change disk, if python env is installed in a different disk than the python code. Then manually switching is needed. For example, python code is under D disk and env is under C disk, here we do: D: before running the python code.

REM run the python code
Path_to_code\sample_code.py

REM Deactivate the environment
call %venv_root_dir%\deactivate.bat
cd original_dir
exit /B 1

1.5 Debugging tips

• Close python program. Double click the bat file and see whether it will automatically triggers the program before move to next steps.
• If it doesn’t work, copy .bat file command line by line to Command window(CMD) and debug thru error messages.
• Common issues: incorrect path settings; some packages in virtual enviroment may crushes and usually reinstalling them will solve the problem.

Step2: Step up windows task Scheduler

2.1. Open Task Scheduler App, select Actions: Create Task.

2.2 In pop-up window, fill in task details including Name, Description, Security Options.

2.3 Select Triggers (add New) and from Begin the task dropdown manu, select At startup.

2.4 Select Actions tabl, select New and add an action: Start a program.

Select Browse and add the path of the bat file.

Done! Congrats! You can restart your computer and test.