ADC PHP enabling shell script throws errors

Question

Hi, guys.
I recently tried to enable PHP on my MacBook Pro.
I speak some bash, but no AppleScript.
On the Apple Developer Center they write you a little script to enable PHP, which failed repeatedly before numerous edits by me. I eventually massaged the script to work, but I want to understand *why* the script didn't work.
The code they give is as follows (and you can find it here: http://developer.apple.com/mac/articles/internet/phpeasyway.html):
set admin_email to (do shell script "defaults read AddressBookMe ExistingEmailAddress")
user_www=$HOME/Sites
filename=php-test
user_index=${user_www}/${filename}.php
user_db=${user_www}/${filename}-db.sqlite3
# NOTE: Having a writeable database in your home directory can be a security risk!
conf=`apachectl -V | awk -F= '/SERVER_CONFIG/ {print \$2}'| sed 's/"//g'`
conf_old=$conf.$$
conf_new=/tmp/php_conf.new
touch $user_db
chmod a+r $user_index
chmod a+w $user_db
chmod a+w $user_www
echo "Enabling PHP in $conf ..."
sed '/#LoadModule php5_module/s/#LoadModule/LoadModule/' $conf | sed
"s^[email protected]^\$admin_email^" > $conf_new
echo "(Re)Starting Apache ..."
osascript <<EOF
do shell script "/bin/mv -f $conf $conf_old; /bin/mv $conf_new $conf;
/usr/sbin/apachectl restart" with administrator privileges
EOF
Here are where this code throws errors for me:
First:
set admin_email to (do shell script "defaults read AddressBookMe ExistingEmailAddress")
I don't even recognize the shell syntax that this would work in. It's sort of csh like. Is this AppleScript?
Anyway, OS X bash chokes on this at the first '(' and I changed it to:
admin_email=`defaults read AddressBookMe ExistingEmailAddress`
which works just fine.
Second:
chmod a+r $user_index
I have no idea how his is supposed to work without 'touch $user_index'
I added:
touch $user_index
to the script.
Third:
conf=`apachectl -V | awk -F= '/SERVER_CONFIG/ {print \$2}'| sed 's/"//g'`
Okay, this actually *works*, but I don't know why it should. In my book, it should choke on the \$2, because the \ is invalid.
I've left it because it works and if it works it isn't wrong, but I would have written:
conf=`apachectl -V | awk -F= '/SERVER_CONFIG_FILE/ {print $2}' | sed 's/"//g'`
which I've tested and also works.
I'd like to know why Apple's first line works.
Fourth:
sed '/#LoadModule php5_module/s/#LoadModule/LoadModule/' $conf | sed "s^[email protected]^\$admin_email^" > $conf_new
The error here is that:
sed "s^[email protected]^\$admin_email^"
doesn't replace [email protected] with the contents of $admin_email.
I don't know what the and are supposed to do, but this just replaces the string '[email protected]' with the string '\$admin_email'
I replaced this with:
sed 's^[email protected]^'$admin_email'^'
This gives me a final script of:
#!/bin/sh
admin_email=`defaults read AddressBookMe ExistingEmailAddress`
user_www=$HOME/Sites
filename=php-test
user_index=${user_www}/${filename}.php
user_db=${user_www}/${filename}-db.sqlite3
conf=`apachectl -V | awk -F= '/SERVER_CONFIG/ {print $2}'| sed 's/"//g'`
conf_old=$conf.$$
conf_new=/tmp/php_conf.new
touch $user_index
touch $user_db
chmod a+r $user_index
chmod a+w $user_db
chmod a+w $user_www
echo "Enabling PHP in $conf ..."
sed '/#LoadModule php5_module/s/#LoadModule/LoadModule/' $conf | sed 's^[email protected]^'$admin_email'^' > $conf_new
echo "(Re)Starting Apache..."
osascript <<EOF
do shell script "/bin/mv -f $conf $conf_old; /bin/mv $conf_new $conf; /usr/sbin/apachectl restart" with administrator privileges
EOF
which works just fine.
But I'm still confused - why did ADC have a code snippet that could have never worked? Or am I missing something obvious?
- Nathan

Answer 1

Hey, RanjeetJones!
You're probably right - it's a lot of code to uncomment a line and change the administrator setting.
And the first time I set up PHP, I just found and edited the config file.
But the script had me so confounded I went back to troubleshoot it and got all wrapped up in why it ended up that way.
And this will help the next coder who wants to learn PHP and maybe doesn't speak bash.
- Nathan