Category: GPL

Managing Component-based Websites with Alfresco

Posted by on November 04, 2012

From time to time at Rivet Logic we get questions concerning Alfresco‘s ability to build and manage component-based websites due to its file / folder based organization. In many cases this question arises from either a limited look at Alfresco’s features (sometimes sourced from industry analyst reports that lack depth) or a far too simplistic understanding of Alfresco’s core capabilities and established best practices for web content management and dynamic content delivery.

Through this short article I will demonstrate the following:

  • Repository organization has no bearing on website placement of components
  • Primary organization in a file / folder structure is a strength and offers technical capability that differentiates Alfresco from lesser Web CMS platforms.

Decoupled CMS ArchitectureThis article will approach this question with the capabilities of Crafter Rivet, a 100% open source web content and experience management solution built as a plug in for Alfresco.  Crafter Rivet consists of two major subsystems:  1) Crafter Studio, an authoring environment built on top of Alfresco’s content repository and 2) Crafter Engine, a high performance content delivery platform which relies on Apache Solr for dynamic content queries. Crafter Rivet and Alfresco enable a de-coupled content management architecture: Crafter Studio and Alfresco for content authoring, management and workflow, and Crafter Engine for high performance dynamic content delivery.  Content is published from Alfresco to the de-coupled Crafter Engine delivery stack, which is where the website application(s) runs. Once deployed to Crafter Engine, content updates are immediately available and are reflected in a high performance, queryable Apache Solr index to support dynamic content delivery.  Moreover, all content is cached in memory for very low response times.

With this understanding of how the separation of content management from content delivery work in a de-coupled Web CMS platform such as Alfresco, we can now discuss how the content organization within the Alfresco repository facilitates component-based site development. We refer to content organization within the repository as the “primary organization” of the content.  Crafter Rivet allows authors to build component-based websites, and place content components anywhere on the site regardless of the primary organization found inside the Alfresco repository.  Components may be placed in a region of a page explicitly through drag-and-drop construction, or they may be surfaced through a dynamic query.

Explicit placement simply links the content to a page through an ID-based association, completely independent of the underlying file/folder structure. Query-driven content placement leverages a Solr-based index and returns a list of component IDs (and other attributes) based on the given criteria. And in both cases, the primary organization of the content plays no role in the ability for the content to be used in any region of any page of the website.

Primary Content OrganizationWithin the repository and authoring life cycle, primary organization is an extremely useful paradigm.  Authors need to be able to find content quickly.  By putting every content item in a structured location (i.e., folder) it is much easier to find when browsing. Contrast this with the opaque database/data structure approach taken by many other platforms which offer no direct access or ability to browse for content.  In general, we have found it best to remove abstraction as much as possible when modeling content. For site pages, as an example, we model these as files and folders that match the URL. Crafter Engine understands that specifically for pages, the URL and this structure are related.  A change in to the folder structure also changes the URL.  This is extremely helpful to authors as it maps directly to their expectation when thinking about page hierarchy in their information architecture.

Components, on the other hand, tend to be grouped by type or some other such criteria. Authors may create arbitrary folder structure to house components, forming a primary organization that enables them to quickly find and work with content. This primary organization has nothing to do with how, when or where the content will be rendered on the site. Further, Alfresco allows content managers to attach rules, policies and permissions to folders inside the repository.  This is an extremely useful and powerful capability not found in may other Web CMS systems. By leveraging the primary organization of pages and components, content managers can enact specific rules for content transformation, metadata extraction, validation, workflow, and much more throughout the authoring life cycle.

 

As you begin to work with Alfresco for web content management you want to keep in mind that the organization of your content inside the repository and the delivery of that content are two very different things.  Alfresco as a content repository is generally de-coupled from the delivery mechanism as we have seen with Crafter Rivet.  Take advantage of the fact that Alfresco’s file / folder structure has many organizational and technical benefits during the authoring life cycle and has no bearing on the delivery of that content when deployed to a dynamic content delivery engine like Crafter Engine.

Resources for Crafter Rivet – Web CMS for Alfresco 4

Posted by on April 16, 2012

Last week was a busy week for those of us working on Crafter Rivet, the WEM/WCM extension for Alfresco 4.0.  We’re extremely excited about this release and are busy scheduling events and demos as word is starting to get out!

You can download Crafter Rivet here:

If you missed our Webinar last week that was co-hosted with Alfresco you can check it out here:
http://www2.alfresco.com/Crafter0412

For existing Alfresco WCM customers on Alfresco version 2 and 3 using the AVM based solution, we’ve put together a couple of blogs to help you think about your migration to Alfresco 4 and the core repository:

For everyone who wants to learn more about this exciting and powerful open source solution for web content and experience management that sits on top of Alfresco, the world’s most open and powerful content management platform, we’re hosting a Crafter Rivet Roadshow in a city near you in May!  Come on out for content packed presentations, demonstrations, Q & A and free lunch!

Sign-up for the Crafter Rivet Roadshow here!

Crafter Roadshow Dates:

San Francisco
Tues. May 8

Los Angeles
Wed. May 9

Chicago
Tues. May 15

New York
Wed. May 16

Boston
Thur. May 17

Washington DC
Tues. May 22

Web CMS on The Alfresco Core Repository (Part 2 of 2)

Posted by on April 10, 2012

In yesterday’s post we covered the fact that Alfresco stopped selling the AVM based WCM solution to new customers.  Existing customers using the AVM based approach will continue to receive support until the AVM reaches end of life status.  New customers looking to Alfresco for WCM/WEM capabilities who read this will naturally wonder what is the approach to WCM on Alfresco.  Existing customers will want to know how to migrate off the AVM and in to Alfresco’s core repository.

As we have seen in yesterday’s post, the core repository has had the benefit of continuous innovation through which it has grown as a platform now capable of supporting use cases critical to WCM/WEM with key features like remote file deployments and form based content capture.  Along with features clearly directed at the WCM use cases, the core repository is host to an amazing array of features and capabilities that make it ideal for all manner of enterprise management, WCM/WEM included.

At Rivet Logic we have made a significant investment in a web content and experience management extension to Alfresco that we call Crafter Rivet. Crafter Rivet is a 100% open source,  full featured application that powers 100s of websites and has over 40 man years of development effort invested in it. Initially Crafter Rivet’s authoring and management capability was based on the AVM. When Alfresco made the decision to direct the full force of its innovation on the core repository we knew it was time to covert. Just released, Crafter Rivet 2.0 is 100% based on the core repository, Solr search and Actviti workflow for Alfresco 4 CE and EE.  Making the switch from the AVM to the core repository required a deep examination of our use cases and the features we would have on hand within the core repository.

Now that we have a background understanding of both the AVM and core repository features we discussed yesterday it is time to look at the use cases that the AVM was designed to address.  We will discuss the use case and how these gaps were addressed by Crafter Rivet.  Let’s get started!

Use Case: Sandboxing
As described in yesterday’s blog, sandboxing is a feature but there are use cases that drive this feature. In a Web CMS context we have times when we need to modify templates, CSS and other assets that have far reaching effects on our sites. There are three common use cases that point to sandboxing:

  • Development:  As a developer I want to work with a template, a CSS file, a JavaScript library, etc. without worrying that the bugs I will inevitably create will interfere with the rest of the teams ability to produce, manage, preview and publish content.
  • Timing: On websites of significant size and complexity, there are often times when projects are created to update the look and feel of the site.  These projects with future delivery dates need to be able to take place without interfering with daily publishing.  Further, it’s important that the project be able keep up with on-going updates to reduce the headache of last minute merges.
  • Playground:  Sometimes we just want to play.  Sandboxes allow us to enable team members to innovate and play around without fear of impacting the live website.

It’s clear that the ability to sandbox (or branch/merge) your website code base can be pretty handy. In my mind there are several key questions:

  • Is the support for this use case a “must have” for my specific environment?  How often do I run in to the use cases above?
  • What granularity of sandboxing do I need?

Many popular Web content management systems do not natively support sandboxing. In a lot of cases the need for the branch merge capability is handled through the development and deployment process. In general I think it safe to say this feature is a rather strong “nice to have” unless you have an site with look and feel components which are literally being constantly updated and where the traditional development process would add too much time to the effort.

When you do need sandboxes the next question is granularity and how sandboxes are used. The AVM UI dictates sandboxes for each user. In my experience accumulated over many Alfresco WCM engagements; is that this was too fined grained for the needs of most engagements.  Most users want to work directly in context with other users.  They need basic locking on individual assets to keep work safe during their edits but they don’t require an entirely separate and parallel universe.  The ability to create a sandbox ad-hoc for a specific purpose maps more directly to the needs we see on the ground. In other words, a sandbox is too granular but a sandbox for a project to update the look and feel of the entire site where users could work together would more aptly address the kind of needs we see.

Crafter Rivet starts with the first finding, that sandboxing is not a “must have” feature and that in-fact when it is applied it should be done so to facilitate specific projects and specific ad-hoc needs. If you look at the way we have structured our content in the core repository you will see we have left room to support one or more draft copies of the site.  In v2.0 we do not support layering in the default configuration; however, Crafter Engine, our content delivery and preview tier, is able to sit over top of multiple hierarchical stores and present them as one store much in the same way the AVM did.

Use Case: History and Reversion in a Web CMS Context
As a user, when I want to preview a version of a specific asset, let’s say a page,  I want to see the page as it was on that day. That means I want to see exactly the same components and assets (images, CSS, js etc) as they were on that given day.  This is a real challenge in the core repository because there is no native support linking assets together under a common version; each asset is individually versioned and the links between objects (associations) do not capture version.

Now to be honest, I have simplified the problem a bit to make a point.  I said that pages, for example, are compound assets and that you are always interested in seeing their dependencies at a given point in time.  This is often the case when we’re talking about images and components that are specific to the page but it’s not really the case when we’re talking about shared assets like templates, CSS, JavaScript, and shared components and shared collateral.  Think for a moment about why users want to look at and ultimately revert to previous versions of content.  They are doing so either:

  • In the short term because they have made a mistake, or
  • in the long term because they need to revert messaging to a previous point in time.

In the first instance there is likely to be no issue.  Common assets are likely going to be the same as they where at the point in time of the version.  However, in the second case, we really want to see the old content in the context of the current templates, etc.  If we revert, it’s to get the older content, but we’re going to deploy it in the context of the latest look and feel of our site.

Handling versioning in Web CMS is a must have, must do capability.

In Crafter Rivet we considered these use cases fully and drew a distinction between two types of relationships.  Those relationships which are page only  and those which are shared commonly amongst other objects in the system.  When you revert a page or any other object, those relationships which are “page only” will revert to a point in time, while other relationships that are common will continue to align to the latest version of the asset.

To accomplish this we leverage both the native versioning capability of the core repository as well as file organization and patterns.  In short, we organize page-only assets in folder structures that represent the page. Page objects are given names that are based on a hash of the object to guarantee a unique name which means in effect that the versioning of the page only object is “horizontal” in the repository. By horizontal I mean that a new file path is used rather than relying on the version store.  Shared objects like pages or other common assets are stored regularly and rely on the native versioning support.  If you revert a page you will revert to an a state where the page points to a different set of file / file paths — achieving a solution for both use cases we mentioned above.

Snapshots
There are several Web CMS use cases that could require snaphsots and version diffs.  For example, some websites have compliance related issues and thus must maintain versions of their sites so that in the event of a dispute over information communicated via the site they can easily prove what the site looked like at a particular moment in time.  The question for snapshots is:

  • Is this something your organization must have?
  • And if so, is it something that the repository has to do for you?

Our experience shows that this feature, for the general market, is a nice to have.  Most customers don’t take advantage of this capability.  When we looked at this capability in Crafter Rivet, we decided it was not important to support natively within the repository itself.  If a customer needs a snapshot every day we simply include a deployment target that would produce a snapshot.

For those wondering about snapshot rollback; our experience has shown that this particular feature is really not relevant to most customers in day to day operation.  The feature has come in handy as a mechanism for bailing out people who have made sweeping changes to a site (100s of files) and deployed them with little or no QA only to find a broken website after the fact.  In such a case, snapshotting a rollback is a life saver.  With a click of a button you can revert 100s of files.

Crafter Rivet, by design is 100% file based. In such a crisis scenario, a simple file based backup could be used to restore a Crafter Rivet based site to a former state.  In the repository, you are unlikely to desire an actual rollback.  It’s more likely that you will want to keep the broken state and simply fix what is wrong and then redeploy the working site.

Moving Forward

Alfresco v4 is an incredible platform and the move to the core repository unlocks all of that capability and innovation. Crafter Rivet is a platform that made use of all of the functionality in the AVM.  And with our new release, we made the move.  You can as well.  More importantly, if you are using the AVM with Alfresco v3 (or even V2), then Crafter Rivet is the perfect solution for your upgrade.  We can provide parity for most needs with a much better user experience that goes way beyond basic Web CMS needs with the coverage of WEM use cases like integrated analytics and reporting, native mobile application authoring, preview, and presentation, content targeting and personalization, multi-channel publishing and much more.  If you’re new customer to Alfresco looking for Web CMS solutions, Crafter Rivet is a comprehensive WCM/WEM solution, with features that rival some of the major players in the industry.

Click here to learn more about Crafter Rivet

Click here to sign up for a our webinar “Crafter Rivet – The WEM Solution for Alfresco 4″ on April 12th at 1pm

Alfresco moves to GPL

Posted by on March 15, 2007

We get lots of questions regarding Alfresco’s move from the Mozilla Public License (plus Attribution) to the GNU GPL.

First off, what is the difference between MPL and GPL?

Well, a primary difference is in the reciprocity requirements. The GPL requires that any derivative work of the original software program be licensed under GPL, whereas the MPL requires only that modifications to one of the files containing Original Code or previous Modifications or a new file containing Original Code or previous Modifications must be released under MPL.

In other words, if GPL code resides anywhere within your end software solution/product (i.e., is compiled in), the entire software code base must be licensed under GPL. In contrast, you may combine/compile MPL code with closed-source code as long as your closed-source code does not mix with the MPL code at the file level.

The bottom line: any OEM or end-user who wants to build a solution using Alfresco Community (GPL) must also release their entire software source code base under GPL. Alfresco provides an exception to this if it involves software licensed under an OSI approved license by virtue of Alfresco’s Free/Libre Open Source Software Exception.

If you are an OEM or end-user who wants to ensure that your modifications, extensions, and customizations to Alfresco remain closed, well that’s where Alfresco’s Enterprise license comes in — it waives the reciprocity requirements of the GPL. This dual-licensing approach to open source software is very common (e.g., MySQL)

So now there are two (independent) reasons to purchase Alfresco Enterprise:

1) Support – to get responsive support and consulting help from Alfresco and their certified partners like Rivet Logic

2) GPL Waiver

Other thoughts:

  • Alfresco is now truly open source as defined by OSI and free software as defined by the Free Software Foundation (”free” as in “free speech”).
  • And as a result, Alfresco’s community should grow much larger. According to John Newton (Alfresco’s Chairman and CTO), this effect has been immediate.
  • Look for more Alfresco integrations with other open source projects.

A great move in all respects.