Session Two: Apache Handlers (loncapa_apache.conf), Authentication and Access Control, Session Environment (Matthew)

Server Content Resource Areas

Internally, all resources are identified primarily by their URL.  Different logical areas of the server are distinguished by the beginning part of the URL:

Authors can only write-access the /~authorname/ space. They can copy resources into the resource area through the publication step, and move them back through a retrieve step. Authors do not have direct write-access to their resource space.

Apache Request Cycle and Handlers

The standard mode in which the Apache web server is used is that a URL corresponds to some static file on the file system, which then more or less gets sent out as-is. Slight deviations from that simple principle are however already the directory listing function, virtual servers, and the cgi-bin directory. In the latter case, Apache executes the file in a new process and provides both the input to the process in the environment, and routes the output to the client. Other deviations are the error messages.

In a more general view, URLs to Apache are URIs (Uniform Resource Identifiers), which may are may not correspond to a physical file, which in turn may or may not be sent out as-is.

As a request for a URI gets sent to the Apache server, it goes through several phases. At each phase (ÒstageÓ) along the process, handler modules can be defined to deal with the request. Details about these phases are given in the Eagle book Chapter 3 (page 60).

These handler modules are not like cgi-scripts executed in a separate process, but are dynamically linked into the Apache child processes themselves Ð they run inside of Apache. The mod_perl mechanism in addition links the Perl interpreter into the Apache child process. Modules are pre-interpreted (ÒcompiledÓ) by the Perl interpreter when they are first loaded, and the pre-interpreted code stays permanently in the memory allocated to that Apache child process. The result is a significant speed-up, and through the flexible mechanism of module registration and different stages of the process, a high degree of customizability.

LON-CAPA does not use Apache::Registry, and so in addition avoids the unnecessary overhead of emulating a cgi-environment within the handlers. Instead, it makes direct use of the Apache Perl API (Chapter 9, Eagle book). 

Handler Definition

Which chain of handler deals with which kind of resource is defined in /etc/httdp/conf/loncapa_apache.conf. LON-CAPA only defines handlers at the (in order) header-parser, access control, and response phase (figure 3-3 Eagle book). In the header-parser phase, the replication handler is run, and in the access-control phase, the various access-handlers. Future handlers will mostly be implemented in the response phase. Fig. 1.2.2 shows excerpts of the configuration script /etc/httpd/loncapa_apache.conf for these modules.

# ------------------------------------------------------------- Access Handlers

<LocationMatch "^/res.*">

PerlAccessHandler       Apache::lonacc

PerlHeaderParserHandler Apache::lonrep

ErrorDocument     403 /adm/login

ErrorDocument     404 /adm/notfound.html

ErrorDocument     406 /adm/roles

ErrorDocument     500 /adm/errorhandler

</LocationMatch>

<LocationMatch "^/priv.*">

PerlAccessHandler Apache::loncacc

SetHandler        perl-script

PerlHandler       Apache::lonconstruct

ErrorDocument     403 /adm/login

ErrorDocument     404 /adm/notfound.html

ErrorDocument     406 /adm/unauthorized.html

ErrorDocument     500 /adm/errorhandler

</LocationMatch>

<LocationMatch "^/raw.*">

PerlAccessHandler Apache::lonracc

</LocationMatch>

<LocationMatch "^/\~.*">

PerlAccessHandler Apache::loncacc

ErrorDocument     403 /adm/login

ErrorDocument     404 /adm/notfound.html

ErrorDocument     406 /adm/unauthorized.html

ErrorDocument     500 /adm/errorhandler

AllowOverride None

</LocationMatch>

É

# --------------------------------------------- Resource Space Content Handlers

<LocationMatch "^/res/.*/$">

SetHandler perl-script

PerlHandler Apache::lonindexer

</LocationMatch>

<LocationMatch "^/res/.*\.tex$">

SetHandler perl-script

PerlHandler Apache::lontex

</LocationMatch>

<LocationMatch "^/res/.*\.page$>

SetHandler perl-script

PerlHandler Apache::lonpage

</LocationMatch>

É

<LocationMatch "^/(res|\~).*\.(xml|html|htm|xhtml|xhtm)$">

SetHandler perl-script

PerlHandler Apache::lonxml

</LocationMatch>

<LocationMatch "^/(res|\~).*\.(problem|exam|quiz|assess|survey|form)$">

SetHandler perl-script

PerlHandler Apache::lonhomework

</LocationMatch>

# -------------------------------------------------------------- Admin Programs

<Location /adm/roles>

PerlAccessHandler       Apache::lonacc

SetHandler perl-script

PerlHandler Apache::lonroles

ErrorDocument     403 /adm/login

ErrorDocument     500 /adm/errorhandler

</Location>

<Location /adm/login>

SetHandler perl-script

PerlHandler Apache::lonlogin

</Location>

É

<Location /adm/annotations>

PerlAccessHandler       Apache::lonacc

SetHandler perl-script

PerlHandler Apache::admannotations

ErrorDocument     403 /adm/login

ErrorDocument     500 /adm/errorhandler

</Location>

É etc É

Fig. 1.2.2 Ð Excerpts of loncapa_apache.conf

Authentication Overview

A user can log into any server in the network and run sessions. The server responsible for initially authenticating the user is the userÕs homeserver.

When a user first accesses a server within a browser session, he or she is challenged to provide authentication information in the form of username, password and domain Ð this is done by lonlogin, which is the error_document for lonacc and loncacc (the normal authentication handlers). When the server receives that information, it asks all library servers in the domain that the user specified to validate the information Ð this is done by lonauth.

The userÕs home server will answer with authorized or non_authorized, all others with unknown_user. If one server authorizes the user, a cookie is returned to the user by lonauth and the session is initialized on the local server by establishing the session environment file. If a server sends non_authorized, the user is rejected.  Fig. 1.3.1 illustrates this process.


Domain

ˆ username, password ˆ Library Server

| § unknown_user §

|

| ˆ username, password ˆ Library Server

| § authorized §

|

User ˆ username,password,domain ˆ Server

§ cookie § store session information for valid cookies

Fig. 1.3.1 Ð Illustration of Authentication Mechanism

At all subsequent interactions, the client sends the cookie back to the server Ð if the cookie is missing or invalid, the user is re-challenged for login information. Handlers are lonacc and loncacc. Cookies expire by closing the browser and are invalidated when the user logs out or logs in a second time into the same machine from another browser.

Authentication Mechanisms, User Data, Passwords

On the library servers, it is a routine in lond that does the authentication. It checks if this is the userÕs homeserver, checks the password, and answers with Òunknown_userÓ, ÒauthorizedÓ or Ònon_authorizedÓ.

Determination if this is the userÕs homeserver is done by the presence of his or her password file in

/home/httpd/lonUsers/domain/1.char/2.char/3.char/username/passwd

for example

/home/httpd/lonUsers/msu/s/m/i/smith/passwd

The password is stored in the format mechanism:info, where mechanism can currently be unix, krb4 or internal. For krb4, the info is the Kerberos domain, for internal it is the crypt password itself. unix simply authenticates against /etc/passwd.

Environment

The access handlers Ð coming early in the Apache request cycle Ð also set up the session environment. The cookie received from the web client is a pointer to the session profiles, which are stored in a directory for temporary files (/home/httpd/lonIDs/).

Standard Components

These are the standard components of the environment added by Apache and the shell.

AUTH_TYPE ---- Basic

DOCUMENT_ROOT ---- /home/httpd/html

GATEWAY_INTERFACE ---- CGI-Perl/1.1

HTTP_ACCEPT ---- image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, image/png, */*

HTTP_ACCEPT_CHARSET ---- iso-8859-1,*,utf-8

HTTP_ACCEPT_ENCODING ---- gzip

HTTP_ACCEPT_LANGUAGE ---- en,pdf

HTTP_CONNECTION ---- Keep-Alive

HTTP_COOKIE ---- SITESERVER=ID=cbc6695505253a2ff0e7bb7110574d90; lonID=kortemey_990461714_msu_msul1

HTTP_HOST ---- zaphod.lite.msu.edu

HTTP_REFERER ----

HTTP_USER_AGENT ---- Mozilla/4.75 (Macintosh; U; PPC)

MOD_PERL ---- mod_perl/1.21

PATH ---- /sbin:/usr/sbin:/bin:/usr/bin:/usr/X11R6/bi¤

QUERY_STRING ----

REMOTE_ADDR ---- 35.8.63.7

REMOTE_PORT ---- 1844

REMOTE_USER ---- lonadm

REQUEST_METHOD ---- GET

REQUEST_URI ---- /adm/test

SCRIPT_FILENAME ---- /home/httpd/html/adm/test

SCRIPT_NAME ---- /adm/test

SERVER_ADDR ---- 35.8.63.51

SERVER_ADMIN ---- korte@lite.msu.edu

SERVER_NAME ---- zaphod.lite.msu.edu

SERVER_PORT ---- 80

SERVER_PROTOCOL ---- HTTP/1.0

SERVER_SIGNATURE ----

SERVER_SOFTWARE ---- Apache/1.3.9 (Unix) (Red Hat/Linux) mod_perl/1.21

Resource Access Control

The following values are set by traceroute at the initialization of the course and are used by access handlers to check if a resource can be served to a user.

acc.cond.msu_12679c3ed543a25msul1.0 ---- 0

acc.cond.msu_12679c3ed543a25msul1.1 ---- 0

acc.res.msu_12679c3ed543a25msul1. ---- &:1&

acc.res.msu_12679c3ed543a25msul1.msu/mmp ---- &welcome267.htm:1&welcomelbs267.htm:0&

acc.res.msu_12679c3ed543a25msul1.msu/mmp/applist/Spectrum ---- &s.htm:1&

acc.res.msu_12679c3ed543a25msul1.msu/mmp/applist/chain ---- &chain.htm:1&

acc.res.msu_12679c3ed543a25msul1.msu/mmp/applist/coulomb ---- &orbit.htm:1&

acc.res.msu_12679c3ed543a25msul1.msu/mmp/applist/induct ---- &faraday.htm:1&

acc.res.msu_12679c3ed543a25msul1.msu/mmp/conversions ----

&conv_area.htm:1&prefixes.htm:1&conv_power.htm:1&intro.htm:1&conv_temperature.htm:1&conv_time.htm:1&conv_velocity.htm:1&conversions.sequence:1&conv_length.htm:1&conv_mass.htm:1&conv_pressure.htm:1&conv_volume.htm:1&conv_energy.htm:1&conv_angle.htm:1&sibaseunits.htm:1&

acc.res.msu_12679c3ed543a25msul1.msu/mmp/kap13 ---- &cd371.htm:1&

acc.res.msu_12679c3ed543a25msul1.msu/mmp/kap16 ----

&cd427.htm:1&cd424.htm:1&Stable.htm:1&cd421.htm:1&Constants.htm:1&cd425.htm:1&cd422.htm:1&kap16.sequence:1&cd426.htm:1&cd423.htm:1&

acc.res.msu_12679c3ed543a25msul1.msu/mmp/kap17 ----

&cd436.htm:1&kap17.sequence:1&cd433.htm:1&cd430.htm:1&cd437.htm:1&cd434.htm:1&cd428.htm:1&cd431.htm:1&cd435.htm:1&cd429.htm:1&geometry.htm:1&cd432.htm:1&

acc.res.msu_12679c3ed543a25msul1.msu/mmp/kap17/calculus ---- &calc.htm:1&

acc.res.msu_12679c3ed543a25msul1.msu/mmp/kap18 ----

&RR440.htm:1&RR449b.htm:1&RR446b.htm:1&cd473.htm:1&RR453.htm:1&RR447.htm:1&RR443b.htm:1&RR449a.htm:1&RR450.htm:1&RR452a.htm:1&RR444.htm:1&RR446a.htm:1&sum18a.htm:1|1&RR441.htm:1&RR443a.htm:1&eField.htm:1&RR454.htm:1&RR444b.htm:1&RR448.htm:1&RR447app.htm:1&RR451.htm:1&RR445.htm:1&RR453a.htm:1&kap18.sequence:1&RR439.htm:1&RR447a.htm:1&RR442.htm:1&RR450a.htm:1&RR444a.htm:1&RR448b.htm:1&RR445newch.htm:1&RR4460app.htm:1&RR455.htm:1&RR441a.htm:1&RR449.htm:1&RR452.htm:1&cd438.htm:1&RR446.htm:1&RR454a.htm:1&sum18.htm:1|1&RR446c.htm:1&RR448a.htm:1&RR451a.htm:1&RR443.htm:1&RR445answer.htm:0&RR445a.htm:1&

acc.res.msu_12679c3ed543a25msul1.msu/mmp/kap18/demo ----

&vid440.htm:0&vid440sm.htm:0&vid449.htm:0&vid449-a.htm:0&vid441.htm:0&vid449sm.htm:0&vid455.htm:0&egun.htm:0&egunsm.htm:0&vid441sm.htm:0&vid449-asm.htm:0&vid455sm.htm:0&

acc.res.msu_12679c3ed543a25msul1.msu/mmp/kap18/problems ----

&cd460b.problem:1&cd458.problem:1&cd462.problem:1&cd457.problem:1&cd461.problem:1&cd460.problem:1&cd464.problem:1&cd459.problem:1&cd463.problem:1&

acc.res.msu_12679c3ed543a25msul1.msu/mmp/kap18a ---- &kap18a.sequence:1&

acc.res.msu_12679c3ed543a25msul1.msu/mmp/kap18a/problems ----

&cd465.problem:1&cd472.problem:1&cd466.problem:1&cd467.problem:1&cd470.problem:1&cd468.problem:1&cd471.problem:1&cd469.problem:1&

É etc for all resources in the course É

Browser Information

browser.mathml ----

browser.os ---- mac

browser.type ---- netscape

browser.version ---- 4.75

Cached Information about Courses and their Description

course.msu_12679c3ed543a16msul1.description ---- lbs267L Lab SS01

course.msu_12679c3ed543a16msul1.domain ---- msu

course.msu_12679c3ed543a16msul1.home ---- msul1

course.msu_12679c3ed543a16msul1.last_cache ---- 990461725

course.msu_12679c3ed543a16msul1.num ---- 12679c3ed543a16msul1

course.msu_12679c3ed543a16msul1.url ---- msu/mmp/lbs267l.sequence

course.msu_12679c3ed543a25msul1.description ---- lbs267 Lecture SS01

course.msu_12679c3ed543a25msul1.domain ---- msu

course.msu_12679c3ed543a25msul1.home ---- msul1

course.msu_12679c3ed543a25msul1.last_cache ---- 990461728

course.msu_12679c3ed543a25msul1.num ---- 12679c3ed543a25msul1

course.msu_12679c3ed543a25msul1.url ---- msu/mmp/lbs267.sequence

course.msu_12679c3ed543a37msul1.description ---- Demo Course

course.msu_12679c3ed543a37msul1.domain ---- msu

course.msu_12679c3ed543a37msul1.home ---- msul1

course.msu_12679c3ed543a37msul1.last_cache ---- 990461725

course.msu_12679c3ed543a37msul1.num ---- 12679c3ed543a37msul1

course.msu_12679c3ed543a37msul1.url ---- msu/korte/demo.sequence

Information Imported from the Environment Database File of the User

environment.favorite.cake ---- Cheese Cake

environment.favorite.color ---- green

environment.firstname ---- Gerd

environment.id ---- z12345678

environment.lastname ---- Kortemeyer

Information about the Request

httpref./res/msu/mmp/ ---- /res/msu/mmp/welcome267.htm

request.ambiguous ---- adm/pages/index.html

request.course.fn ---- /home/httpd/perl/tmp/kortemey_msu_12679c3ed543a25msul1

request.course.id ---- msu_12679c3ed543a25msul1

request.course.sec ----

request.course.uri ---- msu/mmp/lbs267.sequence

request.filename ---- /home/httpd/html/adm/test

request.host ---- zaphod.lite.msu.edu

request.role ---- cc./msu/12679c3ed543a25msul1

request.state ---- published

Information about the User

user.domain ---- msu

user.environment ---- /home/httpd/lonIDs/kortemey_990461714_msu_msul1.id

user.home ---- msul1

user.login.time ---- 990461714

user.name ---- kortemey

Information about User Roles and Privileges

user.priv.au./msu/./ ---- :sma&F:gan&F

user.priv.au./msu/./msu/ ---- :cca&IK:are&F:bre&F:cre&F:ere&F

user.priv.ca./msu/korte./ ---- :sma&F:gan&F

user.priv.ca./msu/korte./msu/ ---- :are&F:bre&F:cre&F:ere&F

user.priv.ca./msu/korte./msu/korte ----

user.priv.cc./msu/12679c3ed543a16msul1./ ---- :sma&F:bre&F:mcr&F

user.priv.cc./msu/12679c3ed543a16msul1./msu/ ----

user.priv.cc./msu/12679c3ed543a16msul1./msu/12679c3ed543a16msul1 ---- :opa&F:srm&F:gan&F:are&F:ccr&IK:cep&IK:cta&IK:cre&F:cst&IK:cin&IK:ere&F:vgr&F

user.priv.cc./msu/12679c3ed543a25msul1./ ---- :sma&F:bre&F:mcr&F

user.priv.cc./msu/12679c3ed543a25msul1./msu/ ----

user.priv.cc./msu/12679c3ed543a25msul1./msu/12679c3ed543a25msul1 ---- :opa&F:srm&F:gan&F:cta&IK:cep&IK:ccr&IK:are&F:cin&IK:cst&IK:cre&F:ere&F:vgr&F

user.priv.cc./msu/12679c3ed543a37msul1./ ---- :sma&F:mcr&F:bre&F

user.priv.cc./msu/12679c3ed543a37msul1./msu/ ----

user.priv.cc./msu/12679c3ed543a37msul1./msu/12679c3ed543a37msul1 ---- :opa&F:srm&F:gan&F:are&F:ccr&IK:cep&IK:cta&IK:cre&F:cst&IK:cin&IK:ere&F:vgr&F

user.priv.cm./ ---- :sma&F:mcr&F:gan&F:bre&F

user.priv.cm./msu/ ---- :mau&F:cca&IK:cad&UIK:ccc&U:cst&UIK:cdg&UIK:are&F:cli&UIK:cta&UIK:cep&UIK:ccr&UIK:bre&F:cau&U:cre&F:cin&UIK:ere&F

user.priv.cm./msu/12679c3ed543a16msul1 ---- :opa&F:srm&F:gan&F:are&F:ccr&IK:cep&IK:cta&IK:cre&F:cst&IK:cin&IK:ere&F:vgr&F

user.priv.cm./msu/12679c3ed543a25msul1 ---- :opa&F:srm&F:gan&F:are&F:ccr&IK:cep&IK:cta&IK:cre&F:cst&IK:cin&IK:ere&F:vgr&F

user.priv.cm./msu/12679c3ed543a37msul1 ---- :opa&F:cst&IK:vgr&F:srm&F:gan&F:are&F:ccr&IK:cep&IK:cta&IK:cre&F:cin&IK:ere&F

user.priv.cm./msu/korte ----

user.priv.dc./msu/./ ---- :sma&F

user.priv.dc./msu/./msu/ ---- :mau&F:cad&UIK:ccr&UIK:cep&UIK:cta&UIK:cli&UIK:ccc&U:cau&U:cst&UIK:cin&UIK:cdg&UIK

user.role.au./msu/ ---- 964531839.0

user.role.ca./msu/korte ---- .

user.role.cc./msu/12679c3ed543a16msul1 ---- 964531839.0

user.role.cc./msu/12679c3ed543a25msul1 ---- 964531839.0

user.role.cc./msu/12679c3ed543a37msul1 ---- 964531839.0

user.role.dc./msu/ ---- 964531839.0

 

Handler Reference: LON-CAPA and the 77 Web Perl Modules

Scott Harrison, freeware volunteer, sharrison@sourceforge.net

LON-CAPA provides many different web services for coordinating online educational interactions. Currently, these web services are made available by 77 different perl modules. The invocation of these perl modules is many times due to the URI format based on entries inside /etc/httpd/conf/loncapa_apache.conf.

Throughout this technical manual, various web perl modules are described in detail. Here is a summary of all the 77 web perl modules:

Name/Location

Description

SOURCE: rat/lonwrapper.pm
TARGET: home/httpd/lib/perl/Apache/lonwrapper.pm

Wrapper for external and binary files as standalone resources. Edit handler for rat maps; TeX content handler.

SOURCE: loncom/publisher/loncfile.pm
TARGET: home/httpd/lib/perl/Apache/loncfile.pm

Provides web-based functionality for file copy, rename, mkdir, etc, in the construction space menu.

SOURCE: loncom/interface/lonstatistics.pm
TARGET: home/httpd/lib/perl/Apache/lonstatistics.pm

Handler to show statistics on solving LON-CAPA problems.

SOURCE: loncom/publisher/londiff.pm
TARGET: home/httpd/lib/perl/Apache/londiff.pm

Handler to show difference between two files.

SOURCE: loncom/publisher/lonupload.pm
TARGET: home/httpd/lib/perl/Apache/lonupload.pm

Handler to upload files through browser into construction space.

SOURCE: loncom/homework/essayresponse.pm
TARGET: home/httpd/lib/perl/Apache/essayresponse.pm

Handler to evaluate essay (ungraded) style responses.

SOURCE: loncom/homework/externalresponse.pm
TARGET: home/httpd/lib/perl/Apache/externalresponse.pm

Handler to evaluate externally graded responses.

SOURCE: loncom/homework/loncapagrade.pm
TARGET: home/httpd/lib/perl/Apache/loncapagrade.pm

Handler to evaluate externally graded responses.

SOURCE: loncom/publisher/lonpubdir.pm
TARGET: home/httpd/lib/perl/Apache/lonpubdir.pm

Handler to publish directories.

SOURCE: loncom/publisher/lonretrieve.pm
TARGET: home/httpd/lib/perl/Apache/lonretrieve.pm

Handler to retrieve old versions from resource space.

SOURCE: loncom/homework/edit.pm
TARGET: home/httpd/lib/perl/Apache/edit.pm

Helper functions when in homework edit mode.

SOURCE: loncom/interface/lonmeta.pm
TARGET: home/httpd/lib/perl/Apache/lonmeta.pm

Metadata display handler.

SOURCE: rat/lonambiguous.pm
TARGET: home/httpd/lib/perl/Apache/lonambiguous.pm

Handler to resolve ambiguous file locations.

SOURCE: rat/lonratparms.pm
TARGET: home/httpd/lib/perl/Apache/lonratparms.pm

Handler to set resource parameters inside of the RAT based on metadata.

SOURCE: rat/lonsequence.pm
TARGET: home/httpd/lib/perl/Apache/lonsequence.pm

Handler for showing sequence objects of educational resources.

SOURCE: loncom/interface/loncreatecourse.pm
TARGET: home/httpd/lib/perl/Apache/loncreatecourse.pm

Allows domain coordinators to create new courses and assign course coordinators.

SOURCE: loncom/interface/loncreateuser.pm
TARGET: home/httpd/lib/perl/Apache/loncreateuser.pm

Allows users to within their own privileges create/edit users and give them roles.

SOURCE: loncom/interface/lonchart.pm
TARGET: home/httpd/lib/perl/Apache/lonchart.pm

Produces simple LectureOnline-like student assessment performance chart

SOURCE: loncom/interface/loncommon.pm
TARGET: home/httpd/lib/perl/Apache/loncommon.pm

Makes a table out of the previous attempts. Inputs result_from_symbread, user, domain, home_server, course_id.

SOURCE: loncom/homework/grades.pm
TARGET: home/httpd/lib/perl/Apache/grades.pm

Handles the viewing of grades.

SOURCE: loncom/homework/imageresponse.pm
TARGET: home/httpd/lib/perl/Apache/imageresponse.pm

Coordinates the response to clicking an image.

SOURCE: loncom/homework/optionresponse.pm
TARGET: home/httpd/lib/perl/Apache/optionresponse.pm

Handles tags associated with showing a list of options.

SOURCE: loncom/homework/outputtags.pm
TARGET: home/httpd/lib/perl/Apache/outputtags.pm

Handles tags associated with output. Seems to relate to due dates of the assignment.

SOURCE: loncom/interface/lontest.pm
TARGET: home/httpd/lib/perl/Apache/lontest.pm

Used for debugging and testing the LON-CAPA system.

SOURCE: loncom/homework/radiobuttonresponse.pm
TARGET: home/httpd/lib/perl/Apache/radiobuttonresponse.pm

Handles multiple-choice style responses.

SOURCE: loncom/interface/lonassignments.pm
TARGET: home/httpd/lib/perl/Apache/lonassignments.pm

Handles processing of assignments.

SOURCE: loncom/interface/loncommunicate.pm
TARGET: home/httpd/lib/perl/Apache/loncommunicate.pm

Will be the access handler to email sending, as well as the planned chatrooms, etc.

SOURCE: loncom/interface/lonerrorhandler.pm
TARGET: home/httpd/lib/perl/Apache/lonerrorhandler.pm

Handles errors.

SOURCE: loncom/interface/lonevaluate.pm
TARGET: home/httpd/lib/perl/Apache/lonevaluate.pm

Handles evaluation.

SOURCE: loncom/interface/lonfeedback.pm
TARGET: home/httpd/lib/perl/Apache/lonfeedback.pm

Handles feedback from students to instructors and system administrators. Provides a screenshot of the current resource, as well as previous attempts if the resource was a homework. Used by lonmsg.pm.

SOURCE: loncom/interface/lonnavmaps.pm
TARGET: home/httpd/lib/perl/Apache/lonnavmaps.pm

Handles navigational maps.

SOURCE: loncom/interface/lonpreferences.pm
TARGET: home/httpd/lib/perl/Apache/lonpreferences.pm

Handles user preferences associated with customizing the online LON-CAPA educational environment.

SOURCE: loncom/interface/lonprintout.pm
TARGET: home/httpd/lib/perl/Apache/lonprintout.pm

Handles the production of printable files and resources.

SOURCE: loncom/interface/lonsearchcat.pm
TARGET: home/httpd/lib/perl/Apache/lonsearchcat.pm

Handles a searchable catalogue.

SOURCE: loncom/interface/londropadd.pm
TARGET: home/httpd/lib/perl/Apache/londropadd.pm

Allows course coordinators to upload courselists in different formats, and automatically create users (if they do not exist already), assign them the role of student in a course, and add them to the classlist.

SOURCE: loncom/interface/lonmsg.pm
TARGET: home/httpd/lib/perl/Apache/lonmsg.pm

lonmsg.pm has several functions to send and receive internal messages. author_res_msg - send message to resource author. user_crit_msg - send a critical message to a user. A critical message will require acknowledgment by the recipient and the sender will be notified. user_crit_received - routine to trigger acknowledgment. statuschange - change the status of a message (read, replied, forwarded, etc). The handler also displays messages, has routines to reply, etc.

SOURCE: loncom/homework/hint.pm
TARGET: home/httpd/lib/perl/Apache/hint.pm

This handler coordinates the delivery of hints to students working on LON-CAPA problems and assignments.

SOURCE: loncom/interface/lonspreadsheet.pm
TARGET: home/httpd/lib/perl/Apache/lonspreadsheet.pm

Spreadsheets are completely web-based. They exist on the level of a whole course, a student, and individual assessments.

SOURCE: loncom/interface/lonparmset.pm
TARGET: home/httpd/lib/perl/Apache/lonparmset.pm

Handler to resolve ambiguous file locations

SOURCE: loncom/publisher/lonconstruct.pm
TARGET: home/httpd/lib/perl/Apache/lonconstruct.pm

Page wrapper for handling construction space.

SOURCE: loncom/publisher/lonpublisher.pm
TARGET: home/httpd/lib/perl/Apache/lonpublisher.pm

Publishes an LON-CAPA educational resource complete with metadata (authorship, language, copyright, creation date, etc).

SOURCE: loncom/interface/lonmenu.pm
TARGET: home/httpd/lib/perl/Apache/lonmenu.pm

Has routines which control the remote control.

SOURCE: rat/lonpageflip.pm
TARGET: home/httpd/lib/perl/Apache/lonpageflip.pm

Deals with forward, backward, and other page flips.

SOURCE: rat/lonratedt.pm
TARGET: home/httpd/lib/perl/Apache/lonratedt.pm

Builds up frame set and loads in the right thing.

SOURCE: loncom/html/res/adm/pages/homeworkmenu.html
TARGET: home/httpd/html/res/adm/pages/homeworkmenu.html

Homework remote control.

SOURCE: loncom/html/res/adm/pages/annotator/admannotations.pm
TARGET: home/httpd/lib/perl/Apache/admannotations.pm

This will take annotations and then plug them into a page.

SOURCE: loncom/html/res/adm/pages/bookmarkmenu/admbookmarks.pm
TARGET: home/httpd/lib/perl/Apache/admbookmarks.pm

This will take bookmarks and get/write/display them for the LON-CAPA user interface.

SOURCE: rat/lonratsrv.pm
TARGET: home/httpd/lib/perl/Apache/lonratsrv.pm

Handler that takes output from RAT and stores it on disk. Handles the upper hidden frame of the added window that comes up in RAT. (3 frames come up in RAT server, code, and output. This module handles server connection.)

SOURCE: rat/lonpage.pm
TARGET: home/httpd/lib/perl/Apache/lonpage.pm

bundles pages into one page

SOURCE: rat/lonuserstate.pm
TARGET: home/httpd/lib/perl/Apache/lonuserstate.pm

compile course into binary data structure (in loncom/rat)

SOURCE: loncom/xml/lontex.pm
TARGET: home/httpd/lib/perl/Apache/lontex.pm

Handler for tex files (somewhere in modules)

SOURCE: loncom/xml/lontexconvert.pm
TARGET: home/httpd/lib/perl/Apache/lontexconvert.pm

Access to tth/ttm

SOURCE: loncom/xml/lonxml.pm
TARGET: home/httpd/lib/perl/Apache/lonxml.pm

XML Parsing Module

SOURCE: loncom/xml/lonplot.pm
TARGET: home/httpd/lib/perl/Apache/lonplot.pm

XML-based plotter of graphs

SOURCE: loncom/xml/style.pm
TARGET: home/httpd/lib/perl/Apache/style.pm

Style Parsing Module

SOURCE: loncom/xml/londefdef.pm
TARGET: home/httpd/lib/perl/Apache/londefdef.pm

Tags Default Definition Module

SOURCE: loncom/xml/run.pm
TARGET: home/httpd/lib/perl/Apache/run.pm

used to prevent poorly written problems from causing lingering after effects

SOURCE: loncom/xml/scripttag.pm
TARGET: home/httpd/lib/perl/Apache/scripttag.pm

implements <script>, <scriptlib>, <parserlib>, and <import>

SOURCE: loncom/homework/randomlabel.pm
TARGET: home/httpd/lib/perl/Apache/randomlabel.pm

Interface for producing applet code which randomizes the labelling of an image.

SOURCE: loncom/homework/lonhomework.pm
TARGET: home/httpd/lib/perl/Apache/lonhomework.pm

handles requests for output, evaluation, and alteration of a homework resource

SOURCE: loncom/homework/inputtags.pm
TARGET: home/httpd/lib/perl/Apache/inputtags.pm

produces HTML input tags (<INPUT>) for rendering homework resources

SOURCE: loncom/homework/structuretags.pm
TARGET: home/httpd/lib/perl/Apache/structuretags.pm

produces HTML tags necessary for structuring the presentation of homework resources

SOURCE: loncom/homework/response.pm
TARGET: home/httpd/lib/perl/Apache/response.pm

defines different types of responses given to student as well as syntax for producing response values

SOURCE: loncom/homework/caparesponse/caparesponse.pm
TARGET: home/httpd/lib/perl/Apache/caparesponse.pm

handles request to the CAPA homework processing engine

SOURCE: loncom/xml/Safe.pm
TARGET: home/httpd/lib/perl/Safe.pm

Meant to safely substitute for CPAN version of Safe. Allows for safely executing embedded perl comands in a way that does not threaten the operating system.

SOURCE: loncom/auth/localauth.pm
TARGET: home/httpd/lib/perl/localauth.pm

Local authentication mechanism (meant to be customized).

SOURCE: loncom/auth/lonacc.pm
TARGET: home/httpd/lib/perl/Apache/lonacc.pm

(This module, like loncacc.pm also authenticates with cookies.) lonacc.pm coordinates access to a wide range of administrative-type functions (e.g. roles, logout, annotations, and bookmarks) as well as coordinating access to educational resources.

SOURCE: loncom/auth/lonracc.pm
TARGET: home/httpd/lib/perl/Apache/lonracc.pm

access handler for file transfers

SOURCE: loncom/auth/loncacc.pm
TARGET: home/httpd/lib/perl/Apache/loncacc.pm

This module provides access to an educational resource construction area. This module is invoked by the URL-related pattern syntax LocationMatch "^/priv.*" or LocationMatch "^/\~.*". Authentication of user identity is coordinated through cookies. The abbreviation "cacc" corresponds to "construction-space access"). If the cookie handle is invalid, then this module returns a forbidden status and makes appropriate log entries. If the cookie handle is valid, status is determined to be okay (and, for the "priv"-type access, the resource is delivered by the lonconstruct module).

SOURCE: loncom/auth/lonauth.pm
TARGET: home/httpd/lib/perl/Apache/lonauth.pm

authenticate, set up session environment

SOURCE: loncom/auth/lonlogin.pm
TARGET: home/httpd/lib/perl/Apache/lonlogin.pm

login screen

SOURCE: loncom/auth/lonlogout.pm
TARGET: home/httpd/lib/perl/Apache/lonlogout.pm

logout

SOURCE: loncom/lonnet/perl/lonrep.pm
TARGET: home/httpd/lib/perl/Apache/lonrep.pm

replication

SOURCE: loncom/auth/lonroles.pm
TARGET: home/httpd/lib/perl/Apache/lonroles.pm

This perl handling module reads in the available roles available for a LON-CAPA user (different courses, different privileges, etc) and produces a form-element HTML page which allows the user to select which role he wishes to exercise in the LON-CAPA system. For instance, a user may want to select between being a student in a thermodynamics physics course or a teaching assistant for an introductory calculus class.

SOURCE: loncom/interface/lonindexer.pm
TARGET: home/httpd/lib/perl/Apache/lonindexer.pm

cross server filesystem browser

SOURCE: loncom/interface/groupsort.pm
TARGET: home/httpd/lib/perl/Apache/groupsort.pm

Implements a second phase of importing multiple resources into the RAT. Allows for reordering the sequence of resources.

SOURCE: loncom/lonnet/perl/lonnet.pm
TARGET: home/httpd/lib/perl/Apache/lonnet.pm

This file is an interface to the lonc processes of the LON-CAPA network as well as set of elaborated functions for handling information necessary for navigating through a given cluster of LON-CAPA machines within a domain. There are over 40 specialized functions in this module which handle the reading and transmission of metadata, user information (ids, names, environments, roles, logs), file information (storage, reading, directories, extensions, replication, embedded styles and descriptors), educational resources (course descriptions, section names and numbers), url hashing (to assign roles on a url basis), and translating abbreviated symbols to and from more descriptive phrases or explanations.

SOURCE: loncom/homework/lectureonline.lcpm
TARGET: home/httpd/html/res/adm/includes/lectureonline.lcpm

Intended for providing perl functions for the <script></script> environment in a problem that was converted from lectureonline.

SOURCE: loncom/homework/default_homework.lcpm
TARGET: home/httpd/html/res/adm/includes/default_homework.lcpm

Provides many functions for the <script> environment in a .problem. Functions are documented in CVS:loncapa/doc/homework/homework5.html.