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- Setup e configurazione di MySQL per utilizzo in congiunzione con PHP+Apache
- Introduzione a PHP
Virtual HostsIP-based virtual hosts use the IP address of the connection to determine the correct virtual host to serve. Therefore you need to have a separate IP address for each host. With name-based virtual hosting, the server relies on the client to report the hostname as part of the HTTP headers. Using this technique, many different hosts can share the same IP address. Name-based virtual hosting is usually simpler, since you need only configure your DNS server to map each hostname to the correct IP address and then configure the Apache HTTP Server to recognize the different hostnames. Name-based virtual hosting also eases the demand for scarce IP addresses. Therefore you should use name-based virtual hosting unless there is a specific reason to choose IP-based virtual hosting. Some reasons why you might consider using IP-based virtual hosting: Some ancient clients are not compatible with name-based virtual hosting. For name-based virtual hosting to work, the client must send the HTTP Host header. This is required by HTTP/1.1, and is implemented by all modern HTTP/1.0 browsers as an extension. If you need to support obsolete clients and still use name-based virtual hosting, a possible technique is discussed at the end of this document. Name-based virtual hosting cannot be used with SSL secure servers because of the nature of the SSL protocol. Some operating systems and network equipment implement bandwidth management techniques that cannot differentiate between hosts unless they are on separate IP addresses.
Sul DNS va creata una nuova zona linux2.tekna ed un nuovo record www che punti sempre allo stesso host: NameVirtualHost 192.168.0.2 # # VirtualHost example: # Almost any Apache directive may go into a VirtualHost container. # The first VirtualHost section is used for requests without a known # server name. #
ServerName www.linux.tekna:80 ServerAlias linux.tekna *.linux.tekna DocumentRoot /var/www/html
ServerName www.linux2.tekna:80 ServerAlias linux2.tekna *.linux2.tekna DocumentRoot /var/www/html/altrodominio
AuthType Basic AuthName "Accesso Protetto" AuthUserFile /var/www/html/passwd/htpasswd Require user david
Autorizzati: david gonzo AuthType Basic AuthName "Accesso Protetto" AuthUserFile /var/www/html/passwd/htpasswd AuthGroupFile /var/www/html/passwd/htgroup Require user david Require group Autorizzati
Order deny,allow Deny from all Allow from 192.168.0.21 #Allow from linux.tekna #Allow from 10.0.0.0/255.0.0.0 #Allow from 10.0.0.0/8
Configurazione di Apache per l’esecuzione di script CGI: (nell’esempio si tratta di codice Perl) ScriptAlias /cgi-bin/ /var/www/cgi-bin/ Vi /var/www/cgi-bin/test.pl #!/usr/bin/perl print "Content-type: text/html\n\n"; print "Ciao a tutti."; Chmod a+x test.pl
(Configurazione ragionevole per la sicurezza ed il log delle informazioni del db) [mysqld] user=mysql (il db gira con i privilegi dell’utente mysql e non root) port = 3306 socket = /var/lib/mysql/mysql.sock skip-locking set-variable = key_buffer=16M set-variable = max_allowed_packet=1M set-variable = table_cache=64 set-variable = sort_buffer=512K set-variable = net_buffer_length=8K set-variable = myisam_sort_buffer_size=8M
log = /var/log/mysql/mysqld-query.log log-bin = /var/log/mysql/mysqld-bin.log log-bin-index = /var/lib/log/mysqld-index.log log-slow-queries = /var/log/mysql/mysqld-slow-queries.log long-query-time = 15 (bind all’indirizzo del database server) bind-address = 192.168.0.2 (solo il DBA può creare utenti) safe-user-create local-infile = 0 skip-name-resolve skip-symlink (se il database riceve richieste solo da PHP locale è inutile attivare le richieste via rete) skip-networking
CREATE TABLE nominativi ( ID_USER INT(5) AUTO_INCREMENT NOT NULL, -> COGNOME VARCHAR(40) BINARY, -> NOME VARCHAR(40) BINARY, -> TELEFONO VARCHAR(15), -> EMAIL VARCHAR(30), -> INDIRIZZO VARCHAR(120), -> PRIMARY KEY(ID_USER));
mysql> insert into nominativi values('','Bandinelli','David','055684507','david@agbms.ch','Via del Bandino 30 - 50126 - Firenze'); Query OK, 1 row affected (0.00 sec) mysql> insert into nominativi values('','Pone','Umberto','0556842507','umberto.pone@agbms.ch','Via del Pallino 32 - 50124 - Firenze'); Query OK, 1 row affected (0.00 sec) PHPMyAdmin (Consolle di amministrazione web di MySQL) http://www.phpmyadmin.net/home_page/ Per l’installazione è sufficiente scompattare il pacchetto nella Document Root di Apache e modificare il file di configurazione. Il file di configurazione si chiama: config.inc.php Se viene ricevuto un errore nella connessione al DB da PHPMyAdmin come questo “Error php: mysql_connect(): Client does not support authentication protocol” La soluzione: mysql -u root -p SET PASSWORD FOR user@localhost = OLD_PASSWORD('password'); Il problema è dovuto alla versione della libreria con cui PHP si connette a MySQL la quale effettua l’hash delle password in modo diverso dalle nuove versioni di MySQL. Introduzione a PHPPHP (recursive acronym for "PHP: Hypertext Preprocessor") is a widely-used Open Source general-purpose scripting language that is especially suited for Web development and can be embedded into HTML. Notice how this is different from a script written in other languages like Perl or C -- instead of writing a program with lots of commands to output HTML, you write an HTML script with some embedded code to do something (in this case, output some text). The PHP code is enclosed in special start and end tags that allow you to jump into and out of "PHP mode". What distinguishes PHP from something like client-side JavaScript is that the code is executed on the server. If you were to have a script similar to the above on your server, the client would receive the results of running that script, with no way of determining what the underlying code may be. You can even configure your web server to process all your HTML files with PHP, and then there's really no way that users can tell what you have up your sleeve. The best things in using PHP are that it is extremely simple for a newcomer, but offers many advanced features for a professional programmer. Don't be afraid reading the long list of PHP's features. You can jump in, in a short time, and start writing simple scripts in a few hours. What can PHP do? Anything. PHP is mainly focused on server-side scripting, so you can do anything any other CGI program can do, such as collect form data, generate dynamic page content, or send and receive cookies. But PHP can do much more. There are three main fields where PHP scripts are used. Server-side scripting. This is the most traditional and main target field for PHP. You need three things to make this work. The PHP parser (CGI or server module), a webserver and a web browser. You need to run the webserver, with a connected PHP installation. You can access the PHP program output with a web browser, viewing the PHP page through the server. See the installation instructions section for more information. Command line scripting. You can make a PHP script to run it without any server or browser. You only need the PHP parser to use it this way. This type of usage is ideal for scripts regularly executed using cron (on *nix or Linux) or Task Scheduler (on Windows). These scripts can also be used for simple text processing tasks. See the section about Command line usage of PHP for more information. Writing client-side GUI applications. PHP is probably not the very best language to write windowing applications, but if you know PHP very well, and would like to use some advanced PHP features in your client-side applications you can also use PHP-GTK to write such programs. You also have the ability to write cross-platform applications this way. PHP-GTK is an extension to PHP, not available in the main distribution. If you are interested in PHP-GTK, visit its own website. PHP can be used on all major operating systems, including Linux, many Unix variants (including HP-UX, Solaris and OpenBSD), Microsoft Windows, Mac OS X, RISC OS, and probably others. PHP has also support for most of the web servers today. This includes Apache, Microsoft Internet Information Server, Personal Web Server, Netscape and iPlanet servers, Oreilly Website Pro server, Caudium, Xitami, OmniHTTPd, and many others. For the majority of the servers PHP has a module, for the others supporting the CGI standard, PHP can work as a CGI processor. So with PHP, you have the freedom of choosing an operating system and a web server. Furthermore, you also have the choice of using procedural programming or object oriented programming, or a mixture of them. Although not every standard OOP feature is realized in the current version of PHP, many code libraries and large applications (including the PEAR library) are written only using OOP code. With PHP you are not limited to output HTML. PHP's abilities includes outputting images, PDF files and even Flash movies (using libswf and Ming) generated on the fly. You can also output easily any text, such as XHTML and any other XML file. PHP can autogenerate these files, and save them in the file system, instead of printing it out, forming a server-side cache for your dynamic content. One of the strongest and most significant feature in PHP is its support for a wide range of databases. Writing a database-enabled web page is incredibly simple. The following databases are currently supported:
We also have a DBX database abstraction extension allowing you to transparently use any database supported by that extension. Additionally PHP supports ODBC, the Open Database Connection standard, so you can connect to any other database supporting this world standard. PHP also has support for talking to other services using protocols such as LDAP, IMAP, SNMP, NNTP, POP3, HTTP, COM (on Windows) and countless others. You can also open raw network sockets and interact using any other protocol. PHP has support for the WDDX complex data exchange between virtually all Web programming languages. Talking about interconnection, PHP has support for instantiation of Java objects and using them transparently as PHP objects. You can also use our CORBA extension to access remote objects. PHP has extremely useful text processing features, from the POSIX Extended or Perl regular expressions to parsing XML documents. For parsing and accessing XML documents, we support the SAX and DOM standards. You can use our XSLT extension to transform XML documents. While using PHP in the ecommerce field, you'll find the Cybercash payment, CyberMUT, VeriSign Payflow Pro and CCVS functions useful for your online payment programs. At last but not least, we have many other interesting extensions, the mnoGoSearch search engine functions, the IRC Gateway functions, many compression utilities (gzip, bz2), calendar conversion, translation... Python is an interpreted, interactive, object-oriented programming language. It is often compared to Tcl, Perl, Scheme or Java. Python combines remarkable power with very clear syntax. It has modules, classes, exceptions, very high level dynamic data types, and dynamic typing. There are interfaces to many system calls and libraries, as well as to various windowing systems (X11, Motif, Tk, Mac, MFC). New built-in modules are easily written in C or C++. Python is also usable as an extension language for applications that need a programmable interface.
print "\n"; print " \n";print "Ciao\n"; phpinfo(); print " Download 1.08 Mb. Share with your friends:
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