All - thank you for your responses. I really appreciate the perspectives and insight.
Based on some of the responses I should re-clarify that I'm not asking about how best to build projects within Visual Studio, but asking what is best when building projects via CCNet (i.e. automated builds and continuous integration). It is a given that using .sln files when building within Visual Studio is the logical and best choice. If one builds with a solution file then when it breaks, one would only see (using ccnet web dashboard or cctray) that the solution broke and not which actual project broke. This can be rather uncomfortable for debugging if there are many projects in the solution. Also, doesn't this go against the benefits of having an automated build system, that is, so that we can what code is working and what code is not working? If we just use a big, all-inclusive green-light/red-light approach, we lose out on useful feedback that the build system can (and should, IMO) provide. Generally speaking, we cannot presume that there would be a single .sln file that all developers would use, so that would go against the reason for the build process to use the same .sln file that is being used by the developers. Developers sometimes move things around in a solution for debugging purposes, with an example of this being when a developer changes to use a project reference (and includes the project into the solution) instead of an assembly. Because of this, developers don't always use the same exact .sln file or, if they do, there can be frustration amongst developers because the .sln file is being changed between them. As far as having to go through the trouble of having to add a new project to the build script when a new one is created, this also only takes a small bit of time and the need for the project would be caught either when the build breaks and/or when testing occurs. This is just a simple maintenance task and would be required anyway for any new unit tests that would need to be added and executed as well. To rely on developers running unit tests is unfortunately urealistic. We all know that developers running unit tests is the ideal situation but doesn't always happen (and in some shops/teams/groups, does not happen at all); this is why automated unit tests are implemented in build scripts, is it not? That being said, the unit tests then need to occur after a project builds which works with building per project. I agree that ideally unit tests should be in their own separate project, but that is not always the case (e.g. testing internal methods). IMO, unit tests should also be written with the smallest scope possible, when possible, and that would mean that they can be project-based; thus, there should be no "uphill battle". The projects are built in a queue (defined by projects that are dependent on each other) so there would be no outdated versions of a project when testing. One thing that I can see here however is an argument to not run unit tests on projects until after all other projects (regardless if they are required or not for the project unit test) are built successfully; this can be beneficial so as not to hinder the build queue (though this could be resolved by not allowing failed tests to fail the build queue). If a project requires resources that are not in the developer- accessible repository then using the .sln file that a developer uses will not work, since a developer may not have (or should not have) access to them. An example of this is if there a content files like report documents or many .jpgs, .pngs, etc, that need to be included in the deliverable but are kept in a separate not-accessible-to- developers repository. If a project requires obfuscation or any other special processing then this also would not comfortably work if using a .sln file, since there could be licensing, permissions, encryption, etc, constraints. This special processing could of course exist in some post-build or pre- build event using some conditional that checks to see if in or on a specific environment, but now that would put deliverable logic in the code and I don't think that is a good idea since it blurs the area of responsibility between a build master (or deployment team or technical operations department) and the developer or development teams. IMO, there should be no dependency this way between the source code and the automated builds; the source code should exist on it's own. Does this make sense? Thoughts? On May 7, 8:22 pm, Sam Calder <samuel.cal...@gmail.com> wrote: > I agree with Brendan. My point of view: > > > Reasons to use project files and NOT use solution files: > > 1. A .sln file could be modified by a developer for, let's say, > > debugging purposes, and that could cause the build process to fail > > ...and any developer that checks that in & triggers the build needs to be > beaten about the head with a cluebat, same as anyone else who checks in any > other build-breaking change. Solution files generally don't actually contain > much more than GUIDS, project references and build configs (and if you are > unlucky enough to use SourceSafe, source control bindings). It's pretty hard > to screw up a solution file. > > > 2. Solution files can use paths that do not work with the build > > process > > Not if they're referenced correctly (IE. relative paths), and your source > control is structured appropriately. > > > 3. Using solution files goes against having small, more granular > > builds because this would require that a whole solution is retrieved > > from the repository > > Solution files give you a useful layer if indirection. Nothing's stopping > you having a solution file that contains one project, if you want. And if > you have an entire enterprise platform with 50+ project files in one > solution then yes you should consider breaking them up into separate > sensible solutions based on architectural purpose (data layer, common code, > web service, server, client, etc...), with binary dependencies. But you > don't have to break it up into 50+ separate build processes, nor do you have > to consolidate projects just to reduce the number of builds or build > complexity.> 4. Automated unit tests cannot (or at least easily) be executed > upon > > each project build, but would rather have to be done after the whole > solution builds > > Per my response to #3, if your solutions are small and sensible it shouldn't > be that big a problem. In fact you may find you can reuse some of the test > setup/teardown test code, mocks, etc. too. > > > Reasons to NOT use project files and instead use solution files: > > 1. Requires more work to setup the builds > > ...and it requires more work to maintain the existing builds too. You build > project-by-project, any time a new project is added, or renamed, or deleted, > you need to manually modify your build config. I use CCNET to build > solutions, you use it to build projects. I set up my CCNET build config a > year ago, it's maybe 30 lines long and it's hardly been modified since, > despite the fact my team has added maybe 20 projects to the solution file in > that time. Building from solution and having a sensible source-control > hierarchy makes it possible to incorporate changes automatically and > effortlessly. > > > 2. using project files can require having to contend with false > > positives when a changeset covers many projects within the solution > > and a build cycle detects and starts building projects out of > > "order" (this can be resolved by always building a whole queue from > > the beginning, upon a detected change, of course). > > A good reason to use solution files, yes. See my response to #3... split > your entire enterprise solution to sensible layers & components, use good > interface-based design to split dependencies where appropriate, and you'll > find changesets of the type you propose don't actually happen very often - > and when they do, well you've already chained builds between your solution > files to accomodate it anyway... > > One additional benefit you neglected to mention - as a developer you open > and build the solution file. If your build process opens and builds the same > file you can easily guarantee what the developer builds is what the build > process will build. This reliability is extra important if you rely on your > build process to create releases. > > My $0.02. I'd recommend using solution files whenever possible, and only > dropping back to projects if absolutely necessary. > > Cheers, > > - Sam. > > On Thu, May 7, 2009 at 8:10 PM, Brendan Crosser-McGay > <veri...@gmail.com>wrote: > > > Rebuttal to Reasons to use project files and NOT use solution files: > > 1. Solution files maintain internal consistency of environments across all > > projects connected together. Make as many environments that you need when > > you start the project and the solution file allows you to switch > > environments across all projects, and make sure that they are all in sync. > > That's why each project should at least have two environments, Debug and > > Release. Developers who check in changes that break the build is actually a > > useful metric, and can encourage a team to run their unit tests before > > checking in so they don't break the build. Besides, sometimes a broken > > build on a solution can reveal weaknesses that need attention. > > > 2. You are going to have larger issues if you have static paths in your > > solution file. Visual Studio automatically uses dynamic paths in your > > project so it doesn't matter where the solution file and project files are > > as their base, as they can be loaded just about anywhere. The solution file > > should be seen as a "grouping" of files together under a single umbrella to > > achieve a common goal. There isn't an easy way (in visual studio) to > > signify that a certain set of files are essential to the entire set of > > projects besides using solution level folders and files. > > > 3. If you have special needs, make lots of solution files, you can use the > > same projects in as many solutions as you like. > > > 4. The act of an entire solution either passing or failing by means of it > > building is usually a very important metric. Unit tests are typically > > contained in a separate project, and thus you would have an uphill battle > > trying to get useful test results if you were building and testing all > > projects independently. Interdependence testing across projects would be > > sacrificed if it's possible to test one project based on outdated versions > > of another project. > > > Rebuttal to Reasons to NOT use project files and instead use solution > > files: > > 1. Creating a solution in Visual Studio, and then adding specific projects > > you need for the build to function is trivial, and can be done in less then > > a minute or two (depending on how fast your PC is.), all visual studio > > slowness aside. :) I know I have a number of projects in my source control > > that are used in multiple solutions with much success. > > > 2. Visual studio manages this, and resolves dependencies. > > > No disrespects meant, but have you been using Visual Studio for long, or > > are you coming over to it from another IDE or language entirely? Developing > > in Visual Studio would be quite difficult without using the "solution" > > system built into it, especially when developing a number of different > > interdependent projects. The best example I've found so far is > > CruiseControl.NET's source code itself, as it's built in C# and uses a > > solution file with a number of dependent files included. > > > Cheers, > > Brendan > > > On Thu, May 7, 2009 at 4:56 PM, ogaz <mobile1j...@gmail.com> wrote: > > >> I am hoping some of you can offer some thoughts on this-- > > >> I am trying to list reasons to use Visual Studio project files instead > >> of Visual Studio solution files to build projects (e.g. CCNet --> > >> MSBuild task --> .csproj instead of CCNet --> MSBuild task -- > >> > .sln). I am of the thinking that ideally it is **generally** best > >> to build using project files instead solution files. > > >> Reasons to use project files and NOT use solution files: > >> 1. A .sln file could be modified by a developer for, let's say, > >> debugging purposes, and that could cause the build process to fail > >> 2. Solution files can use paths that do not work with the build > >> process > >> 3. Using solution files goes against having small, more granular > >> builds because this would require that a whole solution is retrieved > >> from the repository > >> 4. Automated unit tests cannot (or at least easily) be executed upon > >> each project build, but would rather have to be done after the whole > >> solution builds > > >> Reasons to NOT use project files and instead use solution files: > >> 1. Requires more work to setup the builds > >> 2. using project files can require having to contend with false > >> positives when a changeset covers many projects within the solution > >> and a build cycle detects and starts building projects out of > >> "order" (this can be resolved by always building a whole queue from > >> the beginning, upon a detected change, of course).
