NYPHP March 2009 Presentation

1. Becoming A Bash Ninja

New York PHP

March 24, 2009

Brian Dailey

[email_address]

http://realm3.com/

Agenda

Bash Basics

Keyboard Navigation

Shell Shortcuts

Piping

Shell Tools

GNU Screen

Benchmarking (ab/siege)

1998 Introduced to MS-DOS 5.0

Avid reader of help command.

Windows 95 Required!?! Why? The command line is perfect!

Only switched to GUI reluctantly.

2001-2004: The Dark Depths of Java

First introduction to vi in 2001

Redhat 7.2, Knoppix, DamnSmallLinux

2004 PHP

2006 Ubuntu 6.06 Arrives, immediately embraced.

You're probably already using it.

You'll be able to work from nearly any *nix based computer (including servers).

Huge set of tools available to make your life easier.

It is concise and expressive.

Increased productivity.*

*Productivity can be arbitrarily defined as gettin' 'er done, quickly.

It can be intimidating.

Steep learning curve.

Figure out what you do often.

Automate it.

Determine which tasks take the most of your time.

Can you optimize use of this time?

(Yes, that's a simplification.)

Command line environment

Scripting environment right at your fingertips

All the magic happens right here

Fine print: Debian/Ubuntu shell actually uses dash, not bash.

Doesn't mean you have to run Linux locally!

Set up a development server and use PuTTY.

Install Cygwin inside Windows.

Or use ports of GNU Utilities: http://unxutils.sourceforge.net/

Use Mac Terminal.

Use a Live CD.

Getting from one point to another can be difficult at first. Example:

mysql> SELECT user.id, user.username, user.email, user.address, user.city, user.state, user.name, userfile.file_name, userfile.metadata, userfile.other_stuff FOM user JOIN userfiles ON user.id = userfile.user_id AND user.id BETWEEN 1 AND 100 AND user.created BETWEEN '2008-10-10' AND '2009-10-10' AND user.is_active = 1 AND user.name LIKE 'Frodo%' LIMIT 10;

-Scroll through previous commands Ctrl+U - Clear all before cursor Ctrl+K - Clear all after cursor Ctrl+A - Ctrl+E - Alt+B - Move cursor back one word (Similar to Ctrl+ ) Alt+F - Move cursor forward one word (Ctrl+ -> ) Alt+Bckspc - Delete previous word (Also, Ctrl+W) Alt+. - Recall last command argument Tab - Autocomplete commands, files, folders, and more. Ctrl+L - Clear the screen Ctrl+_ - Undo CTRL+R - Recall previous commands Esc, T - Swap last two words

These shortcuts are nearly universal (bash, MySQL) due to use of the GNU Readline library. Exhaustive list is available here:http://onlyubuntu.blogspot.com/2007/03/bash-shell-keyboard-shortcuts-for-linux.html

Get used to using Tab for auto-completion! $ svn ci -mFixed issue. fil[tab] $ svn ci -mFixed issue. filename.php

[Tab][Tab] shows all available matches: $ svn ci -mFixed issue. f[tab][tab] filename.php frodo_baggins.php friendly_fellow.php

Enable programmable bash completion for further efficiency. $ svn c[tab][tab] catcheckoutclcocopychangelistcicleanupcommitcp

!! - Run the last command (same as +return) !my - Runs last cmd starting with my, e.g., mysql -uroot -p db !my:p - Find last cmd starting with my and print it out (don't execute) vi !$- Replaces !$ with last argument in previous command vi !* - Insert all arguments from previous command

A very useful (and more comprehensive) list is available here: http://mail.linux.ie/pipermail/ilug/2006-May/087799.html

Concept can be thought of as pipes and streams

Negates the need for an application to write to a file, only for another application to read it.

Image Source: Wikipedia

Basic example of standard output: # format an XML file and feed it out to formatted.xml $ xmllint feed.xml --format > formatted.xml # same as above, but append to existing file. $ xmllint feed.xml --format >> formatted.xml

Standard input: $ mysql -uuser -p db1 < schema.sql

Or both: $ mysql -uuser -p db1 < schema.sql > log.txt

Can also redirect stderr (errors).

Use the pipe! $ history | grep svn

Examples of pipe chaining...

Colorize Subversion diff output: $svn diff | colordiff | less -R

Search files for child classes, do not include test files, sort them alphabetically, and paginate. $ grep -r -n -H '^class.*extends.*{$' * | grep -v test | sort | more

Cat a text file containing a list of files and execute git add on each one. $ cat files.txt | xargs git add

less Interactive text pager with search capability.

sort Sort lines (alphabetically, numerically, etc)

grep Regular expression searches

uniq Detect (report or omit) repeated lines

sed Stream EDitor

awk powerful pattern scanning and text processing language

xargs build and execute commands from input

There are a lot more of these tools!

Use sed (Stream EDitor) to filter text from git, and automatically add all untracked files.

$ git status |# display text from Untracked to end of output sed -n '/Untracked/,/$d/p' |# only display lines starting with # followed by a tab sed -n '/#/p' |# Strip out beginning # and whitespace sed 's/#s*//' |# Add the files to the git repo xargs git add

But how are you going to remember this command?

Allows you to map a command to a more complicated statement.

Examples: # List files in friendly format alias l='ls -l' # Colorize svn diff, use less -R to accept colors alias sdv='svn diff | colordiff | less -R' # Do not allow updates or deletes without WHERE clause. alias mysql='mysql --i-am-a-dummy'

Arguments are appended to the command.

Save to /etc/profile (or .bash_profile, .bashrc) to automatically load in new sessions.

# Usage: fun [name] alias fun='echo $1 is having fun!' $ fun Brian is having fun! Brian

Alias is only useful as thebeginningof a command.

Argumentsdon't work well, can't do loops, etc.

Answer? Functions and/or shell scripts!

Look up PHP command arguments: phpargs() { # $1 is the first argument passed # get php page from manual mirror curl -s http://us3.php.net/$1 |# pull all text in target div sed -n '/
/,/
/p' |# strip out HTML tags sed 's/]*>//g' |# strip out line feed tr -d " " # add ending line echo }

Then from the command line: $ phpargs in_array bool in_array ( mixed $needle, array $haystack [, bool $strict] )

The only way to learn scripts is towritethem!

Use find for quick, local searches (includes all subdirectories): # Get rid of all those Windows executables! $ find /var/www -name '*.exe' -exec rm {} ; # Find all files modified in the past 24 hours. $ find /var/www -mtime -1

Use locate (or slocate) to search filesystem using a file index: # run updatedb nightly to update a file index # search for filename.php, filter out svn matches. $ locate filename.php | grep -v svn

Comprehensive Introduction to the shell http://www.linuxcommand.org/learning_the_shell.php

Bash keyboard shortcuts http://onlyubuntu.blogspot.com/2007/03/bash-shell-keyboard-shortcuts-for-linux.html

Bash arguments http://www.deadman.org/bash.html

Bash programmable completion: http://www.debian-administration.org/articles/316 http://freshmeat.net/projects/bashcompletion/

IBM Bash By Tutorial Series http://www.ibm.com/developerworks/library/l-bash.html http://www.ibm.com/developerworks/library/l-bash2.html http://www.ibm.com/developerworks/library/l-bash3.html

Editing text files

Multitasking

Automated deployment, testing, etc.

Benchmarking

What does it do?

Command-prompt multi-tasking (multiplex)

Detachable workstation

If you're accidentally disconnected, easily reconnect without losing anything.

Start new screen php: screen -S php

Reconnect later: screen -r php

Customize your status line so you'll always know what server you're on.

Configuration in ~/.screenrc

Share screen with another user.

Training sessions

Code reviews

Screen allows you to run multiple shells in one terminal.

Command key followed by command (usually Ctrl+A, command)

0/9 Switches between windows

n Switches to the next available window

p Switches to the previous available

A Changes window session name

K Kills a window session

c Creates a new window

[ Then use arrows to scroll up and down terminal, select and copy text.

d Detach window

M Monitor window for activity

List current windows and names

? Help

GNU Screen http://magazine.redhat.com/2007/09/27/a-guide-to-gnu-screen/

Screen Configuration Examples http://softpanorama.org/Utilities/Screen/screenrc_examples.shtml

Most of the usual IDE tools are here:

Syntax highlighting

Code Completion

Error Highlighting

Debugging and Profiling (with xdebug plugin)

Integration with versioning (CVS, SVN, git)

Automatic creation of phpDoc ( /*** )

Abbreviations :abbr teh the :abbr vd var_dump :abbr fn function(

. (Repeat last command)

Build Powerful Macros

Command line still accessible

Highly customizable

Some demonstrations follow...

Andrei Zmievski's excellent vim+PHP guide: http://gravitonic.com/talks/ Include's Andrei's .vim files, plugins, etc.

Getting Started with vim and PHP: http://realm3.com/articles/getting_started_with_vim_and_php

Why, oh WHY, do those #?@! nutheads use vi? http://www.viemu.com/a-why-vi-vim.html

A Slightly Advanced Introduction to Vim http://linuxgazette.net/152/srinivasan.html

Integrating xdebug http://tech.blog.box.net/2007/06/20/how-to-debug-php-with-vim-and-xdebug-on-linux/

vim Shortcuts Cheatsheet http://rayninfo.co.uk/vimtips.html

Styled after Java's ant

XML configuration file

Cross-platform

Automated > Manual

Configuration

Deployment

Testing

Generate documentation:

Run PHP_Codesniffer:

Deploy via SSH:

Now chain everything together. [snip][snip][snip]

On the command line just run code sniffer: $ phing sniffcode

Or to do it all: $ phing

Standardize documentation (all developers generating similar documentation)

Standardize and automate deployment

Run pre-deployment checks

Prevent mistakes.

Configure files with live settings

User Guide http://phing.info/docs/guide/current/

Shell Scripts no More! http://nsslive.net/2009/02/16/shell-scripts-no-more/

Phing: Building With PHP http://www.slideshare.net/hozn/phing-building-with-php

Get a quick and dirty idea of how your code might perform under a heavy load.

ab -Apache HTTP server benchmarking tool

siege -Siege is an http regression testing and benchmarking utility. It was designed to let web developers measure the performance of their code under duress, to see how it will stand up to load on the internet. Siege supports basic authentication, cookies, HTTP and HTTPS protocols. It allows the user hit a web server with a configurable number of concurrent simulated users. Those users place the webserver "under siege."

According to Paul M. Jones, siege is more accurate. http://paul-m-jones.com/?p=413

$ seigehttp://www.example.com ** SIEGE 2.66 ** Preparing 15 concurrent users for battle. The server is now under siege... HTTP/1.1 2000.75 secs:2912 bytes ==> / [...snip...] Lifting the server siege...done. Transactions:32 hits Availability:78.05 % Elapsed time:24.30 secs Data transferred:0.09 MB Response time:2.55 secs Transaction rate:1.32 trans/sec Throughput:0.00 MB/sec Concurrency:3.35 Successful transactions:32 Failed transactions:9 Longest transaction:8.51 Shortest transaction:0.56

Automate repetitive tasks.

Make complex tasks simpler.

Ensure best practices are followed.

Don't re-invent the wheel.

[realm3.com]

brian /at/ realm3.com

twitter.com/brian_dailey

(917) 512-3594

Credit to: Andrew Yochum http://plexpod.com Gennady Feldman http://www.gena01.com

NYPHP March 2009 Presentation

Technology

Transcript of NYPHP March 2009 Presentation