---------------------------------------------------------------------- HP ELOQUENCE A.06.30 - Web Integration via CGI - 2000-06-28 ---------------------------------------------------------------------- This package contains the eloqcgi web integration utility along with two sample applications. It is intended to be used on either the HP-UX or Linux platforms along with the Apache web server. HP Eloquence A.06.20 or A.06.30 is required in order to use the eloqcgi utility. Please note that with A.06.20 one of the following eloqcore patches is required: for the HP-UX platform: PE62-9911290 for the Linux platform: PE62-0002171 (beta) Installation ------------ UNIX: In order to install this patch, you need to unpack it with gzip. Gzip is included with HP-UX 10.x and Linux. Installation requires root privileges. cd /opt/eloquence6 gzip -dc /path/to/eloqcgi-.tar.gz | tar xf - (where is either hpux, linux-libc5 or linux-libc6) Files: share/example/eloqcgi/htdocs/eloq.cgi share/example/eloqcgi/htdocs/sample1.html share/example/eloqcgi/htdocs/sample2.html share/example/eloqcgi/htdocs/elogo100.gif share/example/eloqcgi/prog/HELLO.PROG share/example/eloqcgi/prog/Sample2.PROG share/example/eloqcgi/prog/Sample2b.PROG share/example/eloqcgi/README Web Server Configuration ------------------------ For convenience, an alias URL should be configured which should point to the directory containing the eloqcgi utility. In this directory, your web server should be enabled to execute the eloq.cgi binary. This is accomplished by the following configuration lines. You should add them at the end of your web server's http.conf configuration file (restart your web server afterwards). # Enable HP Eloquence CGI examples Alias /eloqcgi/ "/opt/eloquence6/share/example/eloqcgi/htdocs/" AllowOverride None Options Indexes ExecCGI Order allow,deny Allow from all AddHandler cgi-script .cgi Assumed your web server's host name is www.your-domain.com, the eloqcgi directory can now be addressed with the following URL: http://www.your-domain.com/eloqcgi/ Any such request is now redirected into the /opt/eloquence6/share/example/eloqcgi/htdocs directory. HP Eloquence Configuration -------------------------- The eloqcgi utility invokes eloqcore to run your HP Eloquence programs. These programs should be located in a directory outside your web server's document hierarchy for security reasons. For this purpose you should configure a special HP Eloquence volume named "WWW". This volume should specify a directory where all your web-served programs are located. Add the following line to your eloq.config configuration file to associate the eloqcgi example directory with the "WWW" volume name: VOLUME WWW /opt/eloquence6/share/example/eloqcgi/prog Test your Configuration ----------------------- Use a web browser to access the http://www.your-domain.com/eloqcgi/ URL. You should see a directory listing containing the eloq.cgi binary along with the sample1.html and sample2.html examples and other auxiliary files. If not, check the configuration steps listed above. Click the sample1.html file and enter your name into the form, then click the submit button. You should now see a response page which was generated dynamically by the HELLO.PROG program. If not, please check your web server's error log file for the reason of the failure and review your configuration. Now you should have the eloqcgi environment running which means that you can invoke HP Eloquence programs from any browser. These programs however must be especially tailored to be web-aware. This is described below. If you have the SQL/R example database installed on your system you can also try the sample2.html example which uses the WEBQUERY.PROG program to access the named database. Using eloqcgi ------------- The eloqcgi utility serves as a bridge between the web server and your HP Eloquence programs. This enables you to use HP Eloquence to dynamically create e.g. web pages out of your database content. Once eloqcgi is installed as shown above it is invoked by your web server whenever it receives a request for an URL like this: http://www.your-domain.com/eloqcgi/eloq.cgi/TEST?id=12&no=34 ^ ^ ^ ^ ^ ^ | | | | | | | | | | | param #2 | | | | | | | | | param #1 | | | | | | | TEST.PROG,WWW | | | | | eloqcgi utility | | | virtual eloqcgi directory | your web server's host name In this example, the name of the HP Eloquence program is TEST. This is expanded by eloqcgi to TEST.PROG,WWW, thus the named program is assumed to be located in the "WWW" volume's associated directory. You can also specify an absolute path to your program, as with http://www.your-domain.com/eloqcgi/eloq.cgi/home/prog/TEST In this case the program located at /home/prog/TEST is run. It is also possible to specify a different volume, as with http://www.your-domain.com/eloqcgi/eloq.cgi/TEST,EXAMPLE This runs the TEST.PROG located in the "EXAMPLE" volume's associated directory. Please note that these options give you a lot of flexibility but also may cause serious security problems. To overcome this, you can force a specific volume to be used by setting the EQCGI_VOLUME environment variable before you start you web server. For example, you could put the following lines at the beginning of your web server's start script: EQCGI_VOLUME="WWW" export EQCGI_VOLUME This way, all programs must be located in the "WWW" volume's associated directory. There is no way anymore to override this with absolute paths or alternative volume names. As in the example above, both http://www.your-domain.com/eloqcgi/eloq.cgi/home/prog/TEST or http://www.your-domain.com/eloqcgi/eloq.cgi/TEST,EXAMPLE will result in running TEST.PROG located in the "WWW" volume's associated directory. Decoding parameters ------------------- The URL shown above specifies an HTTP GET request with two parameters: http://www.your-domain.com/eloqcgi/eloq.cgi/TEST?id=12&no=34 The first parameter's name is "id", its value is "12". The second parameter's name is "no", its value is "34". The eloqcgi utility decodes these parameters and puts them into environment variables before your program is run, where the variable names are prefixed with "WWW_". This way you can simply access these two parameters in your HP Eloquence program as follows: Id$=GETENV$("WWW_id") No$=GETENV$("WWW_no") Please note that all parameters are treated as text. This implies that any national characters are automatically converted from ISO 8859-1 to the HP Eloquence internal HP Roman 8 character encoding. For your convenience, your program's output which is sent to the browser is automatically converted to ISO 8859-1. This way, you should not have to deal with any national character conversion when using eloqcgi. The CGI standard defines two methods of passing parameters: 1) The GET method, which works as shown above by appending the parameters to the URL, separated by '?' and '&'. Since the maximum length of an URL is limited, this should not be used to pass a large amount of data. 2) The POST method, where the standard input is used to pass the parameters, so there is virtually no limit on the number of parameters and the size of the data passed. Both methods are supported by eloqcgi automatically and can even be combined. Anyway, use of parameters is optional. Writing CGI Programs with HP Eloquence -------------------------------------- Please note that we cannot give you a complete introduction into CGI programming here. There are a lot of resources available, either as printed books or on the Internet. What we can give you here are some tips to give you a quick starting point. The main issue with CGI programs is that they just process single HTTP requests. On each incoming request they are started, process it and terminate afterwards. Each output must go to the standard output which is actually connected to the browser. Thus, your program should begin with PRINTER IS STDOUT Next, the HTTP protocol requires you to specify the type of content your program creates. If this is HTML, do the following: PRINT "Content-type: text/html" PRINT However, if it is plain text, do the following: PRINT "Content-type: text/plain" PRINT The extra blank line is required by the HTTP protocol. It specifies the end of the HTTP header. Before it, you can add additional header lines. For example, the following header line causes a redirection: PRINT "Location: http://www.hp-eloquence.com" Please refer to our examples in the /opt/eloquence6/share/example/eloqcgi/prog directory for further techniques. Enjoy! Your HP Eloquence Team