How to combine files from different svn locations into a working copy?�
I have finally made a test conversion of our CVS(nt) repositories (note1) and now I need to grasp how to work with our code via svn. Specifically on the PC programming side we are using a number of common source files in many different projects. This has been solved in CVS by creating entries in the CVSROOT/modules file which define a "virtual module" where individual files are collected from different physical modules (or projects in svn language). Such a module is given a name of its own, which is to the user equivalent to a project name and can be checked out. We have many such instances in our PC repository... When a user checks out this virtual module he will get a working copy looking according to the definition in the modules file similar to this: vProject |--- src (all sources from the physical project module) |--- bin (the binary output from the project) |--- cmn (selected files from a "Common" project module) |--- lib (maybe some selected binaries needed by the project) etc... I have looked in the SVN-book and the closest I get is what is described in chapter "Sparse Directories", but it describes how the developer can run a series of manually defined checkouts using the --depth cmd line arguments followed by a number of updates where a wanted file is given as the argument one by one. This is really inconvenient because it means that the full project cannot be checked out by someone not knowing these dependencies and it is also awkward because there are so many individual checkouts/updates to be done to build the working copy. Is there no mechanism mimicking the modules handling in CVS? Or must one include a batch file (on Windows) which contains all of the operations one must perform to create a working copy? Such a batch file could in theory execute all the individual operations to create the working copy starting from the checked out project itself only. But it would be yet another component file to write and maintain and everyone must know how to use it (once) IMPORTANT: We do not want to *copy* the needed files from the common projects into a new project and add them there to svn because then we lose the ability to fix bugs in a central location. If we do then there will be multiple copies of the same file all around the repository. Note1) I had to do these undocumented steps in order to be able to convert the existing CVS repositories to SVN on an Ubuntu16 Server 16.04 box: 1) Set cvs2svn to use the built-in parser. Using cvs would not work in the end because cvs2svn tried to run checkouts, which would not work on a copied repo 2) Delete all files living in the top level of the repos. Only directories seemed to be allowed. 3) I had to prune the reposiotory of all CVS subdirectories (where the cvsnt server stores some kind of attributes) 4) I had to add symbol_strategy_rules=global_symbol_strategy_rules, at the end of the run_options.add_project( loop in the options file With these steps done the conversion succeeded without error messages. We are probably lucky this worked in view of the cvs2svn documentation saying that one risk failure and that it could be helped by using the cvs as parser, which we could not in fact NOT do... -- Bo Berglund Developer in Sweden
Re: How to combine files from different svn locations into a working copy?�
On Sat, Dec 09, 2017 at 06:02:20PM +0100, Bo Berglund wrote: > When a user checks out this virtual module he will get a working copy > looking according to the definition in the modules file similar to > this: > > vProject > |--- src (all sources from the physical project module) > |--- bin (the binary output from the project) > |--- cmn (selected files from a "Common" project module) > |--- lib (maybe some selected binaries needed by the project) > > etc... > > I have looked in the SVN-book and the closest I get is what is > described in chapter "Sparse Directories", Sparse directories are for a different use case: When you want to omit some files and/or directories from a checkout. The closest equivalent to what you describe are svn externals: http://svnbook.red-bean.com/nightly/en/svn.advanced.externals.html
Re: How to combine files from different svn locations into a working copy?�
On Dec 9, 2017, at 12:02 PM, Bo Berglund wrote: > > I have finally made a test conversion of our CVS(nt) repositories > (note1) and now I need to grasp how to work with our code via svn. > Specifically on the PC programming side we are using a number of > common source files in many different projects. FWIW in our firm we use svn externals for this. All our projects are in a monorepo (single monolithic svn repository). Each project has its own trunk/branches/tags directories. The shared code is organized as "libraries" which does not necessarily mean DLLs, but which does mean that they are treated like any other project, with their own trunk/branches/tags, their own version number (not related to the revision number of the repository), development rules/policies, and release cycle. When a larger encompassing project uses such a "library," somewhere under that larger project's trunk directory is a subdirectory with the svn:externals property set to fetch the code of the dependency. Usually we fetch only the "src" subdirectory of the library, because tests, documentation, etc., are not needed. The following is important: in the text of this property, we use the caret (^) syntax rather than specifying an absolute URL so that if the repository is ever moved to a different server, the links will not be broken (i.e., checking out old revisions will work correctly) -- this works because of our monorepo; furthermore we use (IIRC) the @ syntax to specify the exact revision of the external code that we want to use. This is so that the library can continue evolving on its own schedule without causing breakage in dependent projects, which evolve on their own different schedule. When a project decides to update to a newer version of the library, it can do so by changing the external property to refer to the newer revision. Since you asked about sparse checkouts... Note that because all our projects, including such "libraries," are in a monorepo, we can take advantage of Subversion's atomic commits to do global cross-project refactoring such as renaming an identifier in a library and updating all code that will be affected throughout all dependent projects in one atomic commit transaction. This usually requires a checkout that encompasses all such code, which in our case would be huge. One consequence of each project having its own trunk/branches/tags is that a full repo checkout will not only fetch all projects, it will fetch every tagged revision and every branch of every project. This is where sparse checkouts (the "telescoping" feature -- see the --depth argument) come in handy. Currently there is no viewspec to automatically checkout a specific layout (I think someone is working on adding that; not sure though) so we have some Windows .bat files and Unix shell scripts that put together these kinds of checkouts -- generally this means getting each project (the parent directory of the trunk/branches/tags) with --depth=immediates, then updating its trunk directory to --depth=infinity. (I am writing this from memory so please excuse if the argument names are wrong.) Hope this is helpful. The svn book explains these features quite well.
