Re: [Bug-wget] [GSoC Proposal] Python3-based FTP Server for Test Suit and Test Suit Refactoring

[Zihang Chen]

Thanks for your comments! :D


2014-03-07 22:17 GMT+08:00 Darshit Shah <address@hidden>:

> Hi Zihang,
>
> The proposal seems good.
>
>
> On Fri, Mar 7, 2014 at 11:39 AM, 陈子杭 (Zihang Chen) <address@hidden>wrote:
>
>> * this is only a draft, so it's not written according to the GNU GSoC
>> template. When discussion is done, I'll get a formal one done (with
>> schedule etc.) *
>>
>> Briefing
>> ====
>>
>> As is known, a new Python3-based test suite was implemented to replace the
>> old one. And a configurable HTTP server utilizing `http.server` and
>> `http.BaseHTTPRequestHandler` was also implemented. Thus the HTTP server
>> can be configured to respond certain headers according to the
>> configuration
>> in separate test cases.
>>
>> However, a configurable FTP server was not required to be implemented,
>> which breaks the consistency of the test suite of wget. So it's necessary
>> that a configurable FTP server be built.
>>
>> Initial Design
>> ====
>>
>> The test suite consists of two parts: `WgetTest.py` (module that actually
>> runs the tests), servers (configurable HTTP and FTP server). When running
>> test cases, `HTTPTest` instances collect configurations from test cases
>> and
>> start the servers with them so that the HTTP handler will handle the
>> incoming requests according to the configurations (also known as rules).
>>
>> About the FTP server, I think the handler architecture can be applied
>> here:
>> implement multiple handlers corresponding to the FTP commands and register
>> them in server instances automatically. When registering handlers, the
>> server should also inform the handlers about the configurations. When new
>> FTP command arrives, the server invoke the corresponding handler, and then
>> the handler look up the rules itself and do the expected actions. When
>> doing real FTP actions, I intend to use third-party FTP library like the
>> current FTP server (I fear sockets so best not directly touch them).
>>
>> There's two things that are unclear:
>> * the necessity of implementing all the FTP command. I presume that wget
>> wouldn't utilize all of them.
>>
> If you're using a library, e.g. pyftpdlib, I don't see why you'd have to
> implement
> any commands on your own.
>
If the server is configurable, I think I'll have to intercept the commands
so I can apply rules on them. When I say implement FTP command, I mean
creating handle for the command, and invoke library in the handle. I think
that's what mislead you probably.

>   Simply use the library for it.
>
>> * what will the configurations be, do I need to design the tests myself?
>> Or
>> should I also port the Perl scripts to Python3?
>>
> Porting the existing Perl tests should give you a good idea of the various
> configurations that will be needed. Looking up the Wget source is also
> often
> a good idea. Either ways, some of us can help out with identifying and
> writing
> test cases when the time comes.
>
>
>> Test Suite Refactoring
>> ====
>>
>> While reading source, I don't find the test suite pythonic. Multiple parts
>> of it seems unmaintainable. If the test suite can be refactored into a
>> better coded one,  maintainability can further be achieved.
>>
>> Yes. I agree the current python based test suite might advantage from a
> few refactorings. There are a few places where the test suite is quite
> un-pythonic
> and fixing those would be a nice idea.
>
> Examples of unpythonicness:
>> * docstrings out of classes or methods
>> * mutable objects as default argument values
>> * multiple use of operator is (controversial)
>> * writing `_replace_substring (WgetTest.py:119)` instead of utilizing the
>> format specification mini-language
>>
>> Examples of unmaintainability:
>> * referencing attributes which are defined in subclasses (`WgetTest.py:61`
>> references `self.servers` which is defined in its subclass
>> `WgetTest.py:254`)
>> * inappropriate variable names (in `WgetTest.py:254` `self.servers`
>> actually becomes an integer while it regarded normally as a list of
>> servers)
>>
> Yes, the variable names are horrible aren't they? That should be
> refactored. (Shouldn't
> take much time ).
>
>> * no intuitive, self-declarative module hierarchy
>>
> The module hierarchy is slightly complicated. Making it more intuitive
> would help.
>
>>
>> About me
>> ====
>> My name's Zihang Chen. I'm a 3rd undergraduate student from China
>> (timezone: UTC+8). Please forgive me for any mistaken uses of the English
>> language. I have been using Python for 3 years. I mostly code for myself
>> (assignment, interest etc.) Never worked for any open source organizations
>> before, so I'm thrilled to apply for GSoC. You can visit my GitHub
>> page here<https://github.com/mad4alcohol>
>>
>> .
>>
>> Looking forward to your comments. Thanks very much.
>>
>
>
>
> --
> Thanking You,
> Darshit Shah
>
>


-- 
Regards,
Chen Zihang,
Computer School of Wuhan University
---
此致
陈子杭
武汉大学计算机学院