Re: [xwiki-devs] [BRAINSTORM] You're rewriting XWiki, you can use any technology in the world, describe it.

Hi Caleb, From my point of view, before starting to list technologies that would be great for a next generation XWiki you first need to define what your exact target is for XWiki. It is very important to do that because when I look at Jerome's answer I don't necessarly have the feeling he is looking at exactly the same objective as I would. While his technology choices might make a lot of sense for an eCommerce platform, they might not in the Intranet concept. This is a first big significant task which depending on the answers will serve as input on the technology stack to use. Indeed since 2003 when I started XWiki a lot of new technologies and also use cases or delivery methods have florished. For instance Cloud is now a very important delivery method of Web Applications and wether your write for a Cloud service, for Software deployment or for both this might lead to different technology choices. Mobile is another key delivery method that was not there in 2003. On the technology side, SOA, REST, Javascript are everywhere. NoSQL is also a key technology to consider. So let me first try to address the question of what a new XWiki could be used for, what it is currently used for, what are the strength of XWiki and it's weaknesses. First the initial objective which is the reason for XWiki: - building flexible collaborative intranets on top of a Wiki, allowing to quickly build applications, integrate these applications with the content Then a lot of things that users, clients have asked for, developers have done on their own: - providing Knowledge based solutions - building applications on top of the "Application" development features of XWiki (the extension of the previous use case) - providing a full Intranet solution, including what XWiki does natively, but also providing "Advanced Profiles", "Groups", "Social networks", a set of Collaborative Applications (Forum, files, etc..) - building public or internal content web sites with limited editors (CMS use case) - building a web application using XWiki as a framework, using many or little of the XWiki existing functions - just doing a very nice Wiki in an Enterprise or Public context - doing any of these in the "Cloud" context (multi tenant) and allowing users to subscribe to an "use-case" that would be built using the XWiki technology As you can see this is close to the "flavor" discussion we already have and I've voluntarily listed the first three which are the flavors we are currently discussing because this is at XWiki SAS what we see organizations we discuss with are asking for most. We have seen the other uses cases also but either we had difficulties addressing them or it was less natural to use XWiki to address them. The "framework" use case is a very important one here, because if we think XWiki's objective is to be a Framework objective for ANY web application, then this might be incompatible with the Intranet, Knowledge Base and even the Wiki use case. For instance Jerome's use case does not fit in the "Intranet" use case and the problem he has are very different from those you have in an Intranet environment. The "Cloud" one is a very big one also and can lead to radical different technology choices. As we can see many new cloud services are build around NoSQL and there are some good reason for that. It's because the Cloud provider wants a unique platform for all his customers and wants to run the service in a fully multi-tenant way on top of this unique storage mecanism. The objective here is to reduce the operating cost to the maximum, in order to be able to provide a "freemium" service. However this choice might have a lot of benefits in the "Cloud" context, but it is a radical choice which has a lot of impact if you also want to provide your service as "Software" like we do for XWiki. It complexifies the installation, reduces the features of your storage (very little relational queries), is a radical new technology to learn to build on which is still very young (choosen a NoSQL platform today is a very risky bet and supporting multiple technologies is a nightmare). Now not supporting NoSQL does not necessarly mean you cannot go "Cloud" but this goes against the way of doing business in the cloud and complexifies the cloud platform, has scalability issues, etc. Now it's impossible to ignore "Cloud" but it's important to understand which type of "Cloud". Is is a unique Cloud or is it SaaS where your objective is to be able to "host" the service for users and customers. The first choice might mean going NoSQL, the second might mean sticking with traditional Databases. The first choice might mean that you will have a hard time convince "software" users because you also need to convince them to go NoSQL. For me the biggest success we have is for "Intranets" and it has always been the key objective, and what we see is that the "Intranet" use case has lead us to have to address the "full Intranet" solution but also the "CMS" one as some organizations want a unique platform for both publishing and collaboration. There is a lot of pressure also to support all "Social Network" features as there are obvious bridges between a software that would be the main places to manage profile, groups and discussions and another software that want to manage information, knowledge and applications. For me the biggest strength of XWiki is it's flexibility to build Applications and to Customize it. The first objective of XWiki was to allow organizations to setup a wiki start sharing knowledge and then extend their wiki with applications that would organize the information in a better way. This need is still here today (Podio is a good example of the Application concept without the Wiki part to glue everything together). I believe many CMS include more and more "application" features so that you can extend your web site with more advance organizations and features (but CMS don't have the same collaborative aspects). The power of XWiki is to allow to do this fully from your web browser and to do it fast. It is to allow power users (not developers) to participate because they don't need full developer skill (this one is very important when it comes to the technology choices of how XWiki gets extensible). The power of XWiki is to not limit the customizations capabilities to the content but also allow to customize the UI by overidding all templates and then morph the initial web site you created into something else. This power is want allowed XWiki to kind of be a full "framework" for web development, but it could be that we have pushed it too far or not far enough. These strength are particularly talking for some of the users case listed before and for others it can actually be a weakness. The weaknesses of XWiki depend on the use cases. For the "Intranet" use case, our weaknesses have been to not work enough on the UI, to not adapt enough to the actual intranet use cases (this is where flavors come in). Another weakness is not enough separation (but not too much) between content and applications. Applications live in XWiki page but we don't have enough markers to separate them and not enough "SOA" at the XWiki Application level. We can fix this. Other weaknesses are how to address mobile, how to address AJAX development and still allowing power-users (not developers) to participate in this development. We also took too much time to build AppWithinMinutes. There are challenges to allowing power-users to develop and still allow this development to be continued by real developers. On the "framework" use-case it's another analysis. Do we need to allow development in the Wiki if XWiki's job is to compete with web-development frameworks ? Can we go without hosting the development in an IDE and if so should it be Eclipse or a Web based IDE ? Is it compatible to provide development features that are more easily accessible to non power-user (like velocity is) or can we go with more advanced technologies. Etc... there are many questions coming from that. There are many other very interesting questions that will yield different answers. For instance should we do a full AJAX UI. What are the consequences of it. If we go full AJAX, what about URLs ? What about search engine indexing. Can we do CMS if we are full AJAX. Full AJAX means more complex to customize also depending on how it's developped. To summarize we need to "choose" first what we want XWiki to be. Once we all agree on this then we can answer how to build the next generation XWiki. I don't disagree that we should think about this, because it's going to be 10 years in November since I started building XWiki and of course technologies evolve and we need to be able to adapt. I'm looking forward to your opinions on that. Then I propose we discuss for each of the use-cases we consider are the future of XWiki what are the right technologies. Then we also look at the compatibility of technologies with each other. This will give us a lot of answers. One being in which direction do we need to put our technological effort on. Another being more clear about what users and developers can expect from XWiki. Ludovic 2013/3/27 Jerome Velociter <jerome(a)velociter.fr>