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XoWiki: List of the available includelets

Created by Gustaf Neumann, last modified by Benjamin Brink 30 Jun 2017, at 07:11 AM

This is a list of the includelets, which can be included in a xowiki page: 

Collaboration Graph

Created by Gustaf Neumann, last modified by Benjamin Brink 30 Jun 2017, at 07:10 AM

XoWiki: How to save files directly in the wiki

Created by Gustaf Neumann, last modified by Benjamin Brink 30 Jun 2017, at 07:08 AM

In order to save files directly in the wiki, just add a link with the content file:yourfile to a page (as for other links, between curly double brackets).

[[file:oacs-dotlrn-vienna-xowiki.pdf|XoWiki Slides from the Vienna OpenACS conference]]

When the file link is added, and the file does not exist, the wiki marks the link with a handle to upload the file. According to the current policies, everybody who is logged-in has sufficient permissions is allowed to edit pages.. 

Here is an example of a file-link, pointing to the xowiki slides from the the Vienna oacs-dotlrn conference XoWiki Slides from the Vienna OpenACS conference

GETable resources, that should be POSTable resources

Created by Michael Aram, last modified by Benjamin Brink 30 Jun 2017, at 07:05 AM

TODO: These OpenACS-URLs are available via GET requests, but as the associated actions are either not safe or not idempotent (or both), they should be made available only via POST instead...

This is more of a problem nowadays as it was earlier, as current browsers (like Chrome or Safari) tend to fetch resources even before the user hits enter in the address bar (i.e. one cannot easily prevent that an unwanted action is taken while entering a similar URL).

In particular the actual (Jan 2014) versions of Safari on Mac OS X 10.9.1 automatically pre-fetches URLs for an url path, when sub-pages were visited in the past, and a user clicks in the url bar (as soon as it shows possible completions). One can e.g. shut down "automatically" the OpenACS server by on /acs-admin/, since Safari might "prefetch" /acs-admin/server-restart.

This page is only a TODO list, that should become a bug report later...

• /acs-admin/users/become
• /acs-admin/server-restart

OpenACS Performance Tuning

Created by OpenACS community, last modified by Benjamin Brink 30 Jun 2017, at 06:56 AM

OpenACS Performance Tuning

Here is some documentation on general OpenACS performance tuning:

• Boost_your_application_performance_to_serve_large_files
• Diagnosing Performance Problems

Much performance tuning is targeted at the subsystems level, and so you will find some specific tuning information in these pages:

• en:aolserver-admin
• en:postgresql-admin

A broad scope of causes can be attributed to OpenACS performance issues. These forum threads help identify useful diagnostic techniques and accurate testing to help narrow the scope of problem areas etc.

• AOLserver and OpenACS Benchmarks (Why is my OpenACS so slow?)
• Server Performance Benchmarks with Apache Benchmark and Traffic Jamme
• How would one handle 12,000 db backed requests per second?
• Network performance monitoring tools
• Help Needed in Setting up .LRN to Scale
• Why is [my] OpenACS becoming so slow?
• Performance Problems - what is the bottleneck?
• Postgres connections [maxed out] and OpenACS
• Performance boost for older installations

Add extra headers

Created by Rocael Hernández Rizzardini, last modified by Benjamin Brink 30 Jun 2017, at 06:53 AM

Usually you can do it with templates:
<property name="header_stuff">
....
  </property>

But sometimes you want to add it not in just one page, so you usually go to www/site-master.adp, but that is not really good to maintain modularity, so instead, now you can define within your package a tcl callback like this:

ad_proc -public -callback subsite::get_extra_headers -impl my_implementation {} {
    return the stuff that should go into the html headers
} {

    set scripts "...."
    set tags "...."

    set text_to_return $scripts
    append text_to_return $tags

    return $text_to_return

}
 

Using Pound as a reverse Proxy

Created by Nima Mazloumi, last modified by Benjamin Brink 30 Jun 2017, at 06:52 AM

Requirements: You have OpenSSL installed and created a certificate.

Assumptions:

• You have OpenACS 5.2 installed (branch oacs-5-2) under /www/service0
• Your Server has the IP-Address 1.2.3.4
• Pound is running on Port 443 under user "root" and group "users"
• AOLserver on 127.0.0.1, Port 10000
• Your certificate is under "/www/service0/certs/certificate.pem"

For an alternative of pound, see Nginx with a sample configuration from Malte.

In order to use Pound for Load-Balancing and SSL encryption follow the below steps. Call "man pound" for a detailed description of the used parameters.

1. Install Pound

   cd /opt/src
   wget http://www.apsis.ch/pound/Pound-2.1.6.tgz
   tar xzpf Pound-2.1.6.tgz
   cd Pound-2.1.6
   ./configure
   make
   make install

2. Configure Pound

   emacs /usr/local/etc/pound.cfg/usr/local/etc/pound.cfg

   User            "root"
   Group           "users"
   LogLevel        0
   Alive           10

   ListenHTTPS
               Address 1.2.3.4
               Port 443
               Cert "/www/service0/certs/certificate.pem"
               xHTTP 2
               HeadRemove "X-SSL-Request"
               HeadRemove "X-Forwarded-For"
               AddHeader  "X-SSL-Request: 1"

               Service
                   URL ".*"
                   BackEnd
                           Address 127.0.0.1
                           Port 10000
                   End
               End
   End

3. Configure AOLserver

   emacs /www/service0/etc/config.tcl

   set httpport              10000
   set address               127.0.0.1

4. Start Pound+AOLserver

Passing values up from an include

Created by irc community, last modified by Benjamin Brink 30 Jun 2017, at 06:47 AM

following dialog from irc (names changed..) shows how to trick the system to pass values from an include to the calling page. This trick needs to be turned into real documentation.

dave: you can't pass stuff up from an include
dave: you have to use upvar
dave: ie: something like this works
michael: but, yes, the order is important. i.e., if i pass a reference to an include and hope to get/use a modified value, the value will be there *after* the <include>
dave: here is what works :)
dave: if you pass a property to a master template
dave: like this
dave: <property name="foo">@foo</property>
dave: <include src="myinclude">
dave: you can upvar #[template::adp_level] foo myfoo
dave: set myfoo "something"
dave: and something will be passed up to the master
dave: but since the code is just one big script
dave: you can't modify code that happens before
dave: we discussed quite a few times a way to work around that
dave: you could upvar something which would be available AFTER the include in the script
michael: i can do the same thing by passing in a reference
dave: yeah
dave: i just though of tha t:)
dave: cool.
michael: and the value will be there after the include
michael: so i just have to move my <property> tags to the bottom of the adp
dave: although that should be documented somehow that an include is modifying stuff in the caller
dave: i don't think you do. I can't remember. did that ages ago for gp and that code is hopefully long gone :)
michael: yeah, i tried it dave:
dave: cool.
tektubby: aha! one of the 7 mysteries of OpenACS solved.
dave: putting property at the bottom works? pretty clever
michael: when referencing the variable (set to "") before the include, i get "" on the calling page
michael: after the include, i get the modified value

How to contribute code that passes accessibility tests

Created by Rocael Hernández Rizzardini, last modified by Benjamin Brink 30 Jun 2017, at 06:10 AM

About this document

• Status: DRAFT
• Updated: 11-jun-2009

Accessibility Policy

The policy for .LRN is published at .LRN website: Accessibility Policy

Corresponding policy for OpenACS is currently being written and will be published soon.

The conformance level to be satisfied is explained in the "Accessibility Conformance Level" section of the .LRN Accessibility Policy.

The "Accessibility page" refered by the .LRN Accessibility Policy states the conformance level and its domain of aplication for each version of the software.

Web Content Accessibility Guidelines

Note: Although automatic tools, such as TAW and "Cynthia says", may be useful to help the developer/author in addressing accessibility issues by providing informative reports, they can not certify the accessibility level of a page since many things need a manual review. Also, those tools won't be able to check a page protected by user and password (they would report on the login page, the one they can actually reach).

WCAG version 2.0

• Understanding WCAG 2.0: a "must read"
• The guidelines
• How to meet WCAG 2.0 (quick reference)
• Techniques and Failures for the Success Criteria of WCAG 2.0

WCAG version 1.0

• The guidelines: explain how to make Web content accessible to people with disabilities.
• Checklist of checkpoints to satify for each level of conformance. Each checkpoint is followed by one or more links to techniques in the following documents:
  • "Core Techniques for Web Content Accessibility Guidelines 1.0" ([WCAG10-CORE-TECHNIQUES]), which discusses the accessibility themes and general techniques that apply across technologies.
  • "HTML Techniques for Web Content Accessibility Guidelines 1.0" ([WCAG10-HTML-TECHNIQUES]), which provides examples and strategies for authoring accessible Hypertext Markup Language (HTML) content.
  • "CSS Techniques for Web Content Accessibility Guidelines 1.0" ([WCAG10-CSS-TECHNIQUES]), which provides examples and strategies to help authors write Cascading Style Sheets (CSS) as part of accessible content design.
• Techniques: gateway to the aforementioned specific ones.

Contributing Code

Once the requirements are met, to contribute your code follow these instructions (one of the two):

1. How to contribute to OpenACS
2. Contributing code for .LRN: submit your proposal to the .LRN leadership team by:
   • posting at the .LRN Q&A forum
   • joining the weekly meeting on IRC (tuesday at 18:00 CET/CEST)

Resources

on-site resources

• (addressing) Accessibility in .LRN and OpenACS: tutorial from the OpenACS/.LRN conference in Valencia (nov 2008), based on WCAG version 1.0.
• Accessibility Guidelines for OpenACS/.LRN developers: slides from an online tutorial on may 2009, based on WCAG version 2.0.
• .LRN Zen project Standards

External resources

• Web Accessibility Initiative
• Web Accessibility in Mind
• 456 Berea St: Articles and news on web standards, accessibility, and usability

If you need more information on how to address accessibility, post your questions at the forums

.LRN Zen Project: YEF grant

Created by Avni Khatri, last modified by Benjamin Brink 30 Jun 2017, at 05:55 AM

Overview

This page is being used to track the work done for the .LRN Zen Project Phase Two with money received from the YEF grant. The grant will cover work to make the latest forums package conform to WCAG 2.0 AA accessibility standards. The goal is to finish the project in time to apply for a large YEF grant in the next cycle - June 2011.

Team Members

• Dave Bauer
• Avni Khatri
• Carl Blesius
• Emmanuelle Raffenne
• Michael Steigman

Current Status

• Overall status
  • Dave reviewed all of the WCAG 2.0 Guidelines document to get a better understanding of the scope of this project.
    The good news is that since we use consistent templates, forms, etc most of the code is automatically generated and we can make the code generators compliant and just check the output. 
    He's modified the spreadsheet list to combine the checklist and functional steps because it was recommended to go straight to the WCAG documents.

• Action items
  • (Dave) Try out the proposed process on one of the forum pages - 2/16
  • (Avni) Work with Emmanuelle (if she has time) to come up with simplified WCAG 2.0 AA checklist we will use - 2/16
    • http://webaim.org/standards/wcag/checklist 
  • Send Emmanuelle a finalized project plan with estimates and have her review - 2/23