Intro to Subversion Access Control 4.1

Big plans are brewing at WANdisco for 2012, and one project that has just been completed, is Subversion Access Control 4.1.

Access Control 4.1 includes a revamped user interface. The new look makes it easier for users to navigate through the security features offered by Access Control and setup new rules and permissions for Subversion repositories and paths.

The ‘Group’ concept has been replaced with “Teams’ and a new feature has been added to allow the designation of “Team Leader” who is then granted some administrator privileges. Specifically, the Team Leader is able to setup user access rules to a pre-defined repository path (or paths).

We are calling this new feature Delegated Admin since it allows granting of some administrator privileges to users. The context of how this feature could be used might be best described in terms of business units for an enterprise corporation. Consider the following scenario.

A company has 100 Apache Subversion users split into 10 teams, each associated with a separate BU, each team has its own Subversion repository. In the past, Access Control admin can go in and setup repository security rules that applies to all 100 users and repositories. With delegated admin the Access Control administration can create 10 new Teams and assign a Team Leader to each one, specifying the Repository that team should have access to. From there, the Team Leader can log into the system, add/remove the users for the team, and setup multiple rules needed to properly manage those Subversion assets.

Effectively what delegated admin does is allow Team Leaders, people in charge of their respective Business Units, to define and configure their own team rules. Access Control supports the concept of nested-teams which is called Sub-Teams (see screenshot) and this would even allow you to further organize teams from larger sections into multiple sub-sections (eg: West Coast Branch –> Plugins Team; West Coast Branch –> Application Team) and designate a team leader at each level to manage users and rules.

The role of the Access Control administrator now is to simply define Team Leaders and the resources which they can direct access over. Once defined the Team Leader can only create rules that affect their resources meaning the West Coast Branch won’t be able to setup access rules for the East Coast Branch’s repositories and vice-versa.

The ability to delegate some administrator functionality to Team Leaders, and in the context of specific Subversion paths and repositories, is a powerful new feature that will empower enterprise organizations and save time and money. Team Leaders are able to set access restrictions based on the need and requirements of their given team or business unit and no longer have to rely on a single administrator to do that for them.

The First Subversion 1.7 Alpha Release is Available Now and The Community Needs Your Feedback

The long awaited and highly anticipated release of Subversion 1.7 is almost upon us. Like any successful open source project, Subversion needs active participation and feedback from its user community. This is especially true in the case of 1.7, given its emphasis on client-side performance and new client tools. That's why Subversion 1.7.0 alpha-1 has now been made available for user testing. Major 1.7 enhancements include:

• HTTPv2- a protocol rewrite designed to enhance performance by reducing the number of round trips between the client and the server with every request.
• WC-NG - a rewrite of the working copy library that enhances performance by centralizing metadata storage and provides a foundation for supporting features such as shelving and offline commits in future releases.
• svnrdump - a new client tool that provides the same functionality as svnadmin dump and svnadmin load, but on remote repositories. There's no need for administrator access to the source or target repository on on the remote server's filesystem.

A complete list of what's new is available at http://subversion.apache.org/docs/release-notes/1.7.html. Download 1.7 now at: http://www.wandisco.com/subversion/download/1_7-alpha. Contribute to the success of this major new release by providing your feedback at: http://www.svnforum.org/forums/56-Apache-Subversion-1.7.0-Alpha-Support . This is your chance to make a positive impact on the world's most popular version control system and its more than five million users.




Subversion 1.6.17 Now Available

Subversion 1.6.17 was just released today. This newest version provides several key enhancements as well as bug fixes. Most notably, 1.6.17 includes major improvements in checkout performance for large working copies on Windows, greater efficiency of ‘blame – g’ for users dealing with a large amount of mergeinfo and improved error handling on Windows. A detailed list of the changes included in this new release is available at: Subversion 1.6.17 Changes.

Release notes for the entire 1.6.x series can be found at: http://subversion.apache.org/docs/release-notes/1.6.html.

To upgrade to this latest release of Subversion and take advantage of the fixes and enhancements that it offers go to: http://www.wandisco.com/subversion/download

The Next Frontier of Enterprise Software Development: Social Coding For Subversion

WANdisco recently unveiled uberSVN - a major new product available free of charge that transforms Subversion into an open, extensible platform for application lifecycle management (ALM) . In addition to plug-and-play flexibility and rich system and user administration capabilities, uberSVN provides the first-ever social coding environment for Subversion, taking enterprise software development beyond the limits of email, wikis, defect trackers, peer-code-review-tools and other applications typically used to manage projects.

uberSVN’s social coding environment reflects the convergence of social networking paradigms represented by Facebook and Twitter that foster instant communication and the collaborative development models of open source communities where software with features similar to these social networking sites was first used. And it’s having the same positive impact on software quality and developer productivity behind corporate firewalls that it’s had in the open source communities that deliver such market-dominating software as the Apache web server, Linux operating system and even Subversion itself.

uberSVN is organized around development teams and their activities. Each team has a home page that profiles the team members, lists the projects they’re working on, repositories they’re using and their latest activity and status. Team members can see each other’s real-time progress by simply subscribing to Twitter-like feeds that managers can also monitor.

With uberSVN, just like developers in an open source community, software engineers in corporate IT environments can rapidly exchange information and continually learn from one another. The overall skill level of the development team goes up and the all-too-common pitfall of reinventing the wheel is avoided. The end result is higher quality software delivered in far less time.

uberSVN is free. Download it now at: http://www.ubersvn.com/download.

Keeping Multiple Subversion Repositories in Sync

With Subversion 1.4, svnsync was introduced for this purpose. The key problem with using svnsync for multiple Subversion repositories distributed over the WAN is its reliance on a master-slave architecture. While svnsync does provide the advantage of having local read-only repositories at each of the remote development sites, only the master repository is writeable. The master repository is then replicated to the read only slaves. However, the replication process can place a significant load on the network and servers. Because of this, replication tends to happen on an infrequent basis, leaving the read-only slave repositories that remote sites do their checkouts from out of sync with the master much of the time. As a result, commit failures due to update conflicts on the master repository can become a problem. In order to avoid commit failures, developers at the slave repository sites have to do updates over the WAN against the master Subversion repository before doing their commits. This can negate most of the expected network performance and developer productivity benefits of using svnsync in a distributed development environment.

Other solutions such as svk do allow multiple repositories to be readable as well as writeable, but there are no guarantees of consistency across the repositories. A commit can succeed on a developer’s local repository where there are no conflicts, and fail when it’s copied to other sites’ repositories due to update conflicts. This can make administration extremely difficult.

WANdisco solves these problems by turning distributed Subversion repositories into peers. All of the repositories are writeable, and consistency across the repositories is guaranteed. WANdisco’s active-active replication capabilities allow developers to work at LAN speed over the WAN for both read and write operations, while keeping all of the repositories in sync, in effect in real-time. WANdisco also provides self-healing capabilities that automate disaster recovery after a network outage or server failure.