How to see a Windows service dependencies with Pyt

Question

Using the Windows Services console, you can see a service dependencies under Properties > Dependencies. How you can you get the same information with Python? Is there a way to do it with psutil?

Answer 1

You can use the subprocess module to query sc.exe to get info for your service and then parse out the dependencies information. Something like:

import subprocess

def get_service_dependencies(service):
    try:
        dependencies = []  # hold our dependency list
        info = subprocess.check_output(["sc", "qc", service], universal_newlines=True)
        dep_index = info.find("DEPENDENCIES")  # find the DEPENDENCIES entry
        if dep_index != -1:  # make sure we have a dependencies entry
            for line in info[dep_index+12:].split("\n"):  # loop over the remaining lines
                entry, value = line.rsplit(":", 2)  # split each line to entry : value
                if entry.strip():  # next entry encountered, no more dependencies
                    break  # nothing more to do...
                value = value.strip()  # remove the whitespace
                if value:  # if there is a value...
                    dependencies.append(value)  # add it to the dependencies list
        return dependencies or None  # return None if there are no dependencies
    except subprocess.CalledProcessError:  # sc couldn't query this service
        raise ValueError("No such service ({})".format(service))

Then you can easily query for dependencies as:

print(get_service_dependencies("wudfsvc"))  # query Windows Driver Foundation service
# ['PlugPlay', 'WudfPf']