From Client to developer execution

Disclaimer

Disclaimer

This lecture and slides should be used only in humor, and that's how it should be understood

If you find it offensive in any way, please do not use this slides, and go out from the lecture !

What does people think Redis is ?

So what is Redis ?

Open source in memory fast binary safe database that support the following:Key Value information

Arrays/Lists and nested lists

Sets/Sorted Sets

Hashes

Type of Message Queue

Distributed work

Ah, yes, but what is Redis ?

Hello my name is REmote Dictionary Server
prepare to die

OK, it's a Key Value databaseAre you happy now ?

How I met Redis ?

I needed to use it with an Object Pascal based Project, and there was no Object Pascal client

So I started to work on one:https://github.com/ik5/redis_client.fpc

And I still do (when I have free time ...)

What is the first rule of Redis ?

You do not talk about Redis

Redis's developer created most client libraries that exists today

The documentation that you see, well it's can be better:What you read and what that is implemented are different things (sometimes)

There are a lot of missing information, that only trial and error teaches you about them

It is written in plain C for better and worse

The developer of Redis is not very communicative person imho ...

So how do you write a client for Redis ?

Reading the Protocol documentation (well, duh )

Finding that some of the real implementation is different then the protocol itself

Wishing a slow death to the developer

Bitching about it at your blog (posts)

Asking yourself: why don't you use a dynamic programming language ...

Sitting down and solving the problems

Why ?

It's very readable programming language

It's string types (yes in plural) are easy to use

Because it is one of the best compiled programming languages ever existed

Because I can !

Can you show us an example ?

var my_command : TRedisAbstractCommands;

writeln(my_command.ParamsToStr(['a', 3.14, False]));(* output as string : a\r\n3.14\r\nFalse\r\n *)

In soviet Russia several ways implement you

Four ways to implement the client:Thinking like dynamic language (but code in Pascal)

Thinking in C (but code in Pascal)

Thinking in Java/C# (but code in Pascal)

Think in Pascal

I read few implementation of the clients:
Lua, Ruby, Perl, Python, Java and C

Decided on the 4th way as the proper way

Research and documentation
by me on each command !

To infinity and beyond

Data types

TRedisReturnTypeTRedisNullReturnTypeTRedisStatusReturnTypeTRedisErrorReturnTypeTRedisNumericReturnTypeTRedisBulkReturnTypeTRedisMultiBulkReturnType

TPersistent

There shalt be a command !

TRedisObjectTRedisParserTRedisAbstractCommands

Command groupCommand groupCommand groupCommand groupCommand groupCommand group

Few more words regarding commands

Every new version of Redis has new/changes to commands.

Can't support such changes for long time

My library helping you, by allowing you to call commands, never existed when I wrote the client, without going insane !

OK, You might go insane, but not because of my library...

Sockets

TSynaClientTRedisIO

Debug, Errors and log files

Each class can have it's own log file for debug/error or no file at all !

You can use also the same logger for every class

Your own error handlers using callbacks, or just let exception raise up

The final slide

Should we use Redis ?

The final slide

Should we use Redis ?

Oh fuck, it's a Perl lecture, I forgot to add some details on that ...

Redis and Perl

main module: https://metacpan.org/module/Redis

some benchmarks: http://blogs.perl.org/users/wolfgang_kinkeldei/2012/01/perl-is-faster-than-c----can-benchmarks-get-compared.html

servers, plugins, and interesting stuff:https://metacpan.org/module/Redis::Queue

https://metacpan.org/module/Nginx::Redis

https://metacpan.org/module/Redis::hiredis

https://metacpan.org/module/Redis::Client

https://metacpan.org/module/AnyEvent::Redis

https://metacpan.org/module/Protocol::Redis

https://metacpan.org/module/Tie::Redis

https://metacpan.org/module/MojoX::Redis

https://metacpan.org/module/Test::Mock::Redis

https://metacpan.org/module/Dancer::Plugin::Redis

https://metacpan.org/module/RedisDB

https://metacpan.org/module/App::redisp

https://metacpan.org/module/AnyEvent::Hiredis

The final slide

Right, so what did I asked ?

The final slide

Should we use Redis ?

ABCYes

No

All of the above

Credits

Angry bird

Excited

Bored

MemCached

Redis

Buzz Lightyear

Questions ?