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running-php-on-rucs
including files
running on rucs: file-protections
splitting into multiple files
We can take
blend.php (src),
and separate the code from the test-cases:
utils.php (src), and separately
utils-test.php (src).
The directive require-once is a run-time instruction
which just goes to the require'd file and
(effectively) splices it into the current file,
and continues evaluating line-by-line.
(So it's reminiscent of java's import, but
require-once significantly more simple-minded.
Beware trampling on identifiers, and it's poor practice to
have any dangling tags / code in the require'd file.)
This also lets us separate a program that uses blend
from the test cases:
some-web-page.php (src),
and
some-web-page.php (output).
(Can you figure how to fix the errant “\n” on that page?)
Linux Review
You'll want to be familiar with the main options for the following:
- ls -lF — list files in long format (show permissions/timestamp);
use -d to show directories themselves (rather than their contents).
- cd — change directory
- mkdir — make a directory
- chmod — change (permission) mode
- nano — edit a file
(also, vim and emacs are more powerful editors, but harder to learn).
Accessing rucs
Before we even revisit the code, let's talk about rucs
(“radford university computer science”; it's a machine managed by the ITEC department,
not the campus IT division):
How to log on to rucs, so you can run php on it:
First, start the VPN, if you are off campus.
Then, either
use ssh yourUserName@rucs.radford.edu
or
run putty.
Note that if rucs is down, then ruacad.radford.edu can also be used.
Be aware: rucs and ruacad are not the
campus web server, nor the php server!
You don't have accounts on those machines
(although your H: drive is shared by those machines).
In particular: the version of php you run from
rucs's command-line is slightly different than the
version run by php.radford.edu !-o
- How to run a php file:
Either php -a for a quick interactive session;
or
from the command-line, php filename.php.
- How to edit files on rucs:
Either log in to rucs and edit locally (vim, emacs, or pico);
or
from your PC, mount your H: drive and then edit locally
(using Notepad or JEdit or eclipse... but not Word).
Running a php file via the web
Recall that when a web-server gets a request, it decides how to respond.
For php.radford.edu, some of the configuration rules:
-
It only accepts secure (https) connections.
-
For requests of the form ~userName/somePath/someFile.php,
it looks for the H-drive file ~userName/dynamic_php/somePath/someFile.php,
and it runs that .php program.
The program's printed output becomes the response.
-
The .php file must be readable by everybody (since it's being served up to the www),
and it must be non-writable by group,other
(as a security measure: other users can't implant malware into your php program).
Apache runs php with the privileges of the file's owner (su).
Let's put our php program on the web!
-
Place the .php file inside dynamic_php/ on your H: drive.
You may have to create that directory if it doesn't already exist, using mkdir.
-
Make sure the file is world-readable, but not group-writable:
chmod g-w blend.php.
-
Make sure all the folders enclosing your file are other-executable but not group-writable:
chmod g-w . .., chmod o+x . ...
-
One crude way to get things to work:
Set every file to be rwx&nnbsp;r-x&nnbsp;r-x
(whether or not it's a folder, .html file, or .php file):
Recursively change permissions:
chmod -R u=rwx go=rx ~/dynamic_php/
or (using the octal representation of the user/group/other permissions 111 101 101) just
chmod -R 755 ~/dynamic_php/
-
If the php interpreter hits an error, the program terminates with no output
(so nothing is sent back to the client —
status code 500: internal server error)!
To change this default, include at the top of your php program:
home—lects—hws
D2L—breeze (snow day)
radford.edu