On Fri, Jun 6, 2014 at 1:33 AM, Steven D'Aprano <steve+comp.lang.pyt...@pearwood.info> wrote: > In the Unix world, text formats and text > processing is much more common in user-space apps than binary processing. > Perhaps the definitive explanation and celebration of the Unix way is > Eric Raymond's "The Art Of Unix Programming": > > http://www.catb.org/esr/writings/taoup/html/ch05s01.html
Specifically, this from the opening paragraph: """ Text streams are a valuable universal format because they're easy for human beings to read, write, and edit without specialized tools. These formats are (or can be designed to be) transparent. """ He goes on to talk about network protocols, one of the best examples of this. I've idly speculated at times about the possibility of rewriting the Magic: The Gathering Online back-end with a view to making it easier to work with. Among other changes, I'd be wanting to make the client-server communication be plain text (an SMTP-style of protocol), with an external layer of encryption (TLS). This would mean that: 1) Internal testing can be done without TLS, making the communication absolutely transparent, easy to debug, easy to watch, everything. Adding TLS later would have zero impact on the critical code internally - it's just a layer around the outside. 2) Upgrades to crypto can simply follow industry best-practice. (Reminder, to anyone who might have been mad enough to consider this: DO NOT roll your own crypto! Ever! Even if you use a good library for the heavy lifting!) 3) A debug log of what the client has sent and received could be included, even in production, at very low cost. You don't need to decode packets and pretty-print them - you just take the lines of text, maybe adorn or color them according to which were sent/received, and dump them into a display box or log file somewhere. 4) The server is forced to acknowledge that the client might not be the one it expected. Not only do you get better security that way, but you could also call this a feature. 5) Therefore, you can debug the system with a simple TELNET or MUD client (okay, most MUD clients don't do SSL, but you can use "openssl s_client"). As someone who's debugged myriad issues using his trusty MUD client, I consider this to be a *huge* advantage. All it takes is a few simple rules, like: All communication is text, encoded down the wire as UTF-8, and consists of lines (terminated by U+000A) which consist of a word, a U+0020 space, and then parameters to the command. There, that's a rigorous definition that covers everything you'll need of it; compare with what Flash uses, by default: https://en.wikipedia.org/wiki/Action_Message_Format Sure, it might be slightly more compact going down the wire; but what do you really gain? Text wins. ChrisA -- https://mail.python.org/mailman/listinfo/python-list
