Python Forum

I am using a java jar in Pycharm environment to achieve testing in a pythion environment.
To make the application more interactive, we plan to use commandline arguments.

Eg:

python test.py opc.tcp://localhost:XXXX AA

So here, I am testing a AA configuration server at the mentioned URL. Now with this input, all the tests are performed.

The code used is as follows.

class TestClient:
    def __init__(self, URL, Config):
        self.Url = URL
        self.config = Config

    def perform_test(self):
        # subprocess.call(['java','-version'])

        subprocess.call(
            ['java', '-jar', 'XXX.jar', '-url', self.Url, '-config', self.config, '-specVersion',
             '2.0'])  

    def read_results(self):
        pass

if __name__ == "__main__":
    client = TestClient("opc.tcp://localhost:XXXX", "AA")
    client.perform_test()
    client.read_results()

But to enhance further I want the user to type the version number and also the test he wants to do. As in (TEST A) as a parameter. But I also need to give a provision that if he does not provide this paramter, he should be able to perform all tests like previously.

So I have modified the code this way considering overloading.

import re
import sys

import bs4 as bs4

inputURL = sys.argv[1]
inputConfig = sys.argv[2]
version = sys.argv[3]
print(len(sys.argv))
if len(sys.argv) > 4:
    typeOfTest = sys.argv[4]


class TestClient:
    def __init__(self, URL, Config, Version):
        self.Url = URL
        self.config = Config
        self.version = Version

    def __init__(self, URL, Config, Version, TestType):
          self.testType = TestType #here i expect overloading of constructor

    def perform_test(self):
        # subprocess.call(['java','-version'])
        if len(sys.argv) > 4:
            subprocess.call(
                ['java', '-jar', 'XXX.jar', '-url', self.Url, '-config', self.config, '-specVersion',
                 self.version])
        else:
            subprocess.call(
                ['java', '-jar', 'XXX.jar', '-url', self.Url, '-config', self.config, '-specVersion',
                 self.version, '-test', self.testType])

    def read_results(self):
        pass


if __name__ == "__main__":
    if len(sys.argv) > 4:
        client = TestClient(inputURL, inputConfig, version)
    else:
        client = TestClient(inputURL, inputConfig, version, typeOfTest)
    client.perform_test()
    client.read_results()

So, I type on the command line :

python test.py opc.tcp://localhost:XXXX AA 2.0 TESTA

But i get an error saying:

Error:
client = TestClient(inputURL, inputConfig, version)
TypeError: __init__() missing 1 required positional argument: 'TestType'

Is the constructor overloading not poossible here? Please can anyone guide me some alternative?

UPDATE: just understood that funciton overloading is not possible in python. How to achieve this scenario working? any suggestions please

Im just a hobbyist at this but my fix would be to use a default value for TestType parameter and test for it.

def __init__(self, URL, Config, Version, TestType=None):
    if TestType == None:
        ...
    else:
        ...

Python method overloading doesn't work that way. The last __init__ is the only. The other is unreachable. But you can get something very similar to signature overloading using the dispatch decorator.

Could do it like this,so with super() inherit all the methods and properties from its parent.
Then add another parameter in the __init__() function.
I guess also popejose way could work.

import re
import sys

import bs4 as bs4

inputURL = sys.argv[1]
inputConfig = sys.argv[2]
version = sys.argv[3]
print(len(sys.argv))
if len(sys.argv) > 4:
    typeOfTest = sys.argv[4]

class Client:
    def __init__(self, URL, Config, Version):
        self.Url = URL
        self.config = Config
        self.version = Version

    def perform_test(self):
        # subprocess.call(['java','-version'])
        if len(sys.argv) > 4:
            subprocess.call(
                ['java', '-jar', 'XXX.jar', '-url', self.Url, '-config', self.config, '-specVersion',
                 self.version])
        else:
            subprocess.call(
                ['java', '-jar', 'XXX.jar', '-url', self.Url, '-config', self.config, '-specVersion',
                 self.version, '-test', self.testType])

    def read_results(self):
        pass

class TestClient(Client):
    def __init__(self, URL, Config, Version, TestType):
        super().__init__(URL, Config, Version)
        self.testType = TestType

if __name__ == "__main__":
    if len(sys.argv) > 4:
        client = Client(inputURL, inputConfig, version)
    else:
        client = TestClient(inputURL, inputConfig, version, typeOfTest)
        client.perform_test()
        client.read_results()