Difference between revisions of "Web Server"

Revision as of 10:00, 5 March 2008

This entry contains information on the packages installed in the web server and the process followed for their installation.

The Wiki began very late in the process, so it will be completed slowly over time.

PHP

GD Library

Since I used a non-graphical utility to get weather data, I have to make my own graphics... so I wanted to use the GD library. While the default installation is supposed to have GD installed, something was not working.

Patrick Lam helped me out by deleting the old library:

 rm /usr/local/lib/libgd*

and then restarting apache. (He used "/etc/init.d/apache2 restart" instead of what I used: "apache2 -k restart", although both should work).

This entry helps me remember how to delete old libraries which may be 'corrupt' (the current guess is that when installing things for gallery2, the gd library was corrupted).

Data Warehouse (Oracle) Access

In order to get access to the data Warehouse, I had to install PHP support for Oracle.

I installed the Oracle OCI interface, specifically the "Oracle 10 Instant Client" to

 /usr/local/pkgs/oracle/instantclient_10_2

Needed both the Basic and SDK versions from:

 http://www.oracle.com/technology/software/tech/oci/instantclient/htdocs/linuxsoft.html
 instantclient-basic-linux32-10.2.0.3-20061115.zip
 instantclient-sdk-linux32-10.2.0.3-20061115.zip

This part simply required to 'unzip' the files to the directory.

The directions at http://ubuntuforums.org/archive/index.php/t-92528.html were very helpful. The basic steps I did, I think, were:

 mkdir -p /usr/local/pkgs/oracle/instantclient_10_2
 cd /usr/local/pkgs/oracle/instantclient_10_2
 unzip instantclient-basic-linux32-10.2.0.1-20050713.zip
 unzip instantclient-sdk-linux32-10.2.0.1-20050713.zip
 echo /usr/local/pkgs/oracle/instantclient_10_2 >> /etc/ld.so.conf
 ldconfig

Create symbolic links:

 ln -s libclntsh.so.10.1 libclntsh.so
 ln -s libocci.so.10.1 libocci.so

Install OCI8:

 pecl install oci8 (don't remember if I had to install 'pear' before using pecl?)
 Answer ORACLE_HOME = instantclient,/usr/local/pkgs/oracle/instantclient

Modify the /etc/php/apache2/php.ini file:

 Add:
   extension=oci8.so

Add the environment variables to apache:

 To: /etc/apache2/envvars
 Add:
   LD_LIBRARY_PATH="/usr/local/apache2/lib:/usr/lib/oracle/10.2.0.3/client:$LD_LIBRARY_PATH"
   TNS_ADMIN="/usr/lib/oracle/10.2.0.3/client"
   LANG=en_US
   
   export LD_LIBRARY_PATH LANG TNS_ADMIN

(But I'm not sure if this did anything, I had to use "PutEnv" in the PHP code, see below).

Lastly, I had to modify the Oracle files to tell it where the MIT Data Warehouse is:

 Create /usr/local/pkgs/oracle/instantclient_10_2/tnsnames.ora 
 With data:

 warehouse =
   (DESCRIPTION =
     (ADDRESS_LIST =
       (ADDRESS = (PROTOCOL = TCP)(HOST = warehouse.mit.edu)(PORT = 1521))
     )
     (CONNECT_DATA = (SID = DWRHS))
   )

and nothing else in it. THIS IS ESSENTIAL!

To connect to the DW in PHP, I created the interface file oracle.php, with the following basic elements:

 PutEnv("ORACLE_SID=DWRHS");
 PutEnv("ORACLE_HOME=/usr/lib/oracle/10.2.0.3/client/");
 PutEnv("TNS_ADMIN=/usr/lib/oracle/10.2.0.3/client/");
 PutEnv("LD_LIBRARY_PATH=/usr/lib/oracle/10.2.0.3/client/lib");
 
 function ora_query($sql,&$err)
 {
   $conn = oci_pconnect('sailuser','sail2WAREhouse','warehouse');
 
   if (!$conn)
   {
     $err = "No connection!";
     return false;
   }
 
   // empty the error
   $err = "";
 
   // parse the query string
   $stid = oci_parse($conn,$sql);
   if (!$stid)
   {
     $err = oci_error($conn);
     return false;
   }
 
   // execute the actual query
   $res = oci_execute($stid, OCI_DEFAULT);
   if (!$res)
   {
     $err = oci_error($stid);
     return false;
   }
 
   return $stid;
 }

 function ora_fetch_array($res)
 {
   return oci_fetch_assoc($res);
 }

These work mostly equivalent to the mysql 'query' and 'fetch' functions.

Accounts

The server links to the MIT kerberos server to authenticate users. However, when using "SUDO" you must use your local password (which can be the same as your kerberos password, but which would NOT be updated when you change it).

The link to the Kerberos was set to happen automatically by Patrick Lam (Commodore 05-06), so I have no detailed information on that.

To create new accounts:

 adduser <username>
 adduser <username> mitna  <-- to give access to website development

Using the standard adduser process will give the user access either via the local password (set by the admin when calling adduser) or the Kerberos password.

SSL Server Certificates

When certificates expire (they are given for one year at a time), you need to send a new certificate request to

 mitcert@mit.edu

Follow the directions at:

 http://web.mit.edu/apache-ssl/www-rev11/README.certificate

Weather Station

The Weather Station is a Vantage Pro2 hard wired model.

NEW

W View did not make me happy (it could not give 'real-time' results, only show things about every minute or even more... plus I could not get it to save data to the database to interface easily with PHP.

So, I looked more around, and found this super easy program to use:

 http://www.joejaworski.com/weather/

Since our station is in USB and next to the computer, the ONLY software needed is:

 vproweather
 http://www.joejaworski.com/weather/vproweather-0.6.tgz

I downloaded/untared it to:

 /usr/local/pkgs/vproweather-0.6/

A simple 'make' (using sudo) was all that was needed to compile it. Then, running it with:

 /usr/local/pkgs/vproweather-0.6/vproweather -x /dev/ttyUSB0

Gives real time data, and using '-l' instead of '-x' gives low/high data.

I put this in a cron to run the real-time every 1 minute (fastes crontab can do) and update a table in the database, which is then used by the rest of the site (table: weather). The low/high will run once a day.

Hopefully I'll be able to create a daemon which updates the table every 10 seconds or so... we'll see.

OLD

The linux software is W View. I followed the User Manual detailed instructions.

Install (untar) to:

• /usr/local/pkgs/wview-3.3.0

Commands (what should be done next time in order, I did not do it in this order):

• Installed mysqlclient-dev: sudo apt-get install libmysqlclient-dev
• Installed libpng-dev: sudo apt-get install libpng12-dev
• Install 'radlib':
• get .tar
• install to /urs/local/pkgs/radlib-2.7.0
• ./configure
• make
• sudo make install
• edit /etc/ld.so.conf --> add /usr/local/lib --> run ldconfig
• Install 'libgd' (all with sudo):
• get .tar
• install to /usr/local/pkgs/gd-2.0.35
• ./configure
• make
• make install
• ./configure --enable-mysql
• sudo make
• sudo make install

Not working! Will need to check USB drivers/connection