We have 2 solutions.
SolutionA is an internal solution where we put reusable code through our products
For the sake of the question, it has only two projects NugetProjectA and NugetProjectB which has a project reference to NugetProjectA.
SolutionB its a solution that has package references towards SolutionA via nuget.
The thing that troubles is:
add new method added in NugetProjectA
add new method in NugetProjectB project that uses previous method
publish new version of NugetProjectB
update nuget reference on Project of SolutionA
execute in Project newly added method of NugetProjectB
Since we didn't publish the NugetProjectA updated version, last step described will fail.
This seems to be a easy problem to solution. But imagine this with many more projects in SolutionB and many more in SolutionA.
Your question is vague and open-ended, so there isn't a simple, concise answer. Honestly it could easily be a multi-post blog series or even a short book. I'll try to give some general suggestions, but I'm not going to go into a lot of details to avoid making this answer too long.
Mono-repo vs multiple repos
Just like the microservice craze from a few years ago, you should first ask yourself if you need it. Having all your source code in a single repository and solution might make it feel "legacy", and it sure seems nicer to have a 3 minute build of a component rather than a 30 minute build of a whole system when checking in a 1-line bug fix. But are the problems you listed in your question worth the benefit of a shorter CI build?
On the other extreme, Google may famously run almost everything out of a single repository, but they have teams of people doing nothing more than managing their mono-repo and build system because a large number of developers working on a single repo have a different set of problems. These are engineers not working on customer applications. If their work make other teams more productive, then it can be worthwhile.
You need to figure out what's best for you, but given the problem you described in the question, maybe you have too many repos/solutions and your processes could be faster with fewer mistakes if you consolidate a little.
Automation
The next best thing is to just use good engineering practises. Automate as much as possible to reduce the risk of human mistakes, including automating processes that validate that manual processes are followed correctly.
Have the a CI or CD pipeline push packages, so you can't forgot to push dependencies, like in your example.
There are tools that will automatically generate a version number from the git history based on the number of commits since the versioning config file was checked in. This prevents you from forgetting to increment the package version when you check in a change to the package.
Have tests to make sure the package works before pushing it. You could make it as simple as making sure that dependencies exist, but you could also go further and have test programs run that use the package to ensure that backwards compatibility isn't broken and that new features actually work as expected. Have these tests run before pushing the package, so if the tests fail, you don't push a bad package.
You can have a pipeline that will automatically create pull requests on solutions that use a package when a new version of one of your packages is published. You can even automatically merge it, but you'll want to make sure you have real good tests to avoid a buggy package cascading into a huge mess, particularly if you do automatic deployments on successful builds.
Be creative and think about other ways you can automate your processes to make things easier for yourself and your team.
But be pragmatic about what you automate. There's no point spending a week full time to automate something that only takes you 5 minutes once a month to do manually. But if the manual process sometimes goes wrong and causes hours or days of effort to fix, then that makes automating the process more worthwhile.
Use modern features
The .NET ecosystem has changed a lot in the last 2-3 years since .NET Core was announced. Now packing with MSBuild (either dotnet pack or msbuild -t:pack) is easier to create packages than creating .nuspec files and making sure you do the right things to get project dependencies packed as nuget dependencies, getting all files in the right places, etc. If your class library uses SDK style projects, then there's nothing extra to do. If your project is a traditional project, you'll need to use PackageReference for your NuGet dependencies (or specify <ProjectStyle>PackageReference</ProjectStyle> as an MSBuild property in your project file), and then reference the NuGet.Build.Tasks.Pack package.
Version the application, not each package
Like the mono-repo vs multiple repos point, considering versioning all packages in the application with a single version number, rather than versioning each package individually. Yes, this means you'll sometimes (or maybe often) publish a new version of a package that doesn't have any code changes to the previous version, but it simplifies the release considerably. Coupled with packing with MSBuild in the section above, you can create a Directory.Build.props file in your repository root, and set the <Version> property to your app version, and all projects in the repo will have the same version. So, when you're ready to release, bump the version in a single file and every project and every NuGet packages will have the same version.
Summary
In an ideal world each component would be reusable in different applications, in a separate source code repository, each package individually versioned using semantic versioning. But in the real world this adds a lot of development time complexity. Your customers may be happier to get bug fixes and new features more quickly, even if the version number of packages are less meaningful. So, make data driven decisions. If you're frequently having dependency version problems, reduce your dependencies so there are fewer things that can go wrong.
Don't get me wrong, there are many good reasons to have multiple projects, multiple solutions, multiple repositories. Just make sure that the reason you're doing them is because it helps your team/company be more productive, not for idealistic reasons that are slowing you down or causing bugs.
Related
In our build system ,once build is over ,assemblies also will be check-in . But When we were moving to UCM , architects divided in this opininon. Few people supported check-in the compiled assemblies and msi and few were opposing it.
when we were check-in ,we simply do symlinks and it gave us great advantage. Moreover when check-in was done ,it will be removing entries from bin and release folder instead of copy. It helped us lot. Every day people were able to work with latest assemblies check-in by nightly build. Now they are not able to do that. They want me to copy the Nightly build dll to some common place.
On other hands due to every day check-in our repository grows humungous.
I don't know what was the best option.
Can you share your thoughts about which method is better? Is it better to check-in assemblies in UCM/Clearcase or not?
AS a practice, all build outputs should not be kept under source control. But, you have to keep them on a common place until they expire. The philosophy behind this practice is:
The repository size gets larger as you add binaries to it.
The old versions of an assembly produced in a nightly build (belongs to 2 years ago) are useless. On the other hand, the old version of source codes and its history are useful all the time.
In addition to the build results, software products are usually dependent to third party components. These third party components are usually evolved and their newer versions are usually released. Keeping build results in the source control, you have to keep the right version of third party components somewhere else.
Another reason against checkin assemblies in ClearCase is the lack of clean-up feature possible: you cannot easily rmver some versions you might not need without potentially compromising the Vob repo.
This is especially true in UCM where metadata and hyperlinks are added to versions, making the removal of one quite dangerous for the integrity of other objects (like an UCM baseline) depending on it.
For the other, more general, reasons for not versioning binaries, see "Is it good practice to store framework runtimes under source control?" and hsalimi's answer.
I am attempting to convince my colleagues to start using a build server and automated building for our Silverlight application. I have justified it on the grounds that we will catch integration errors more quickly, and will also always have a working dev copy of the system with the latest changes. But some still don't get it.
What are the most significant advantages of using a Build Server for your project?
There are more advantages than just finding compile errors earlier (which is significant):
Produce a full clean build for each check-in (or daily or however it's configured)
Produce consistent builds that are less likely to have just worked due to left-over artifacts from a previous build
Provide a history of which change actually broke a build
Provide a good mechanism for automating other related processes (like deploy to test computers)
Continuous integration reveals any problems in the big picture, as different teams/developers work in different parts of the code/application/system
Unit and integration tests ran with the each build go even deeper and expose problems that would maybe not be seen on the developer's workstation
Free coffees/candy/beer. When someone breaks the build, he/she makes it up for the other team members...
I think if you can convince your team members that there WILL be errors and integration problems that are not exposed during the development time, that should be enough.
And of course, you can tell them that the team will look ancient in the modern world if you don't run continuous builds :)
See Continuous Integration: Benefits of Continuous Integration :
On the whole I think the greatest and most wide ranging benefit of Continuous Integration is reduced risk. My mind still floats back to that early software project I mentioned in my first paragraph. There they were at the end (they hoped) of a long project, yet with no real idea of how long it would be before they were done.
...
As a result projects with Continuous Integration tend to have dramatically less bugs, both in production and in process. However I should stress that the degree of this benefit is directly tied to how good your test suite is. You should find that it's not too difficult to build a test suite that makes a noticeable difference. Usually, however, it takes a while before a team really gets to the low level of bugs that they have the potential to reach. Getting there means constantly working on and improving your tests.
If you have continuous integration, it removes one of the biggest barriers to frequent deployment. Frequent deployment is valuable because it allows your users to get new features more rapidly, to give more rapid feedback on those features, and generally become more collaborative in the development cycle. This helps break down the barriers between customers and development - barriers which I believe are the biggest barriers to successful software development.
From my personal experience, setting up a build server and implementing CI process, really changes the way the project is conducted. The act of producing a build becomes an uneventful everyday thing, because you literally do it every day. This allows you to catch things earlier and be more agile.
Also note that setting build server is only a part of the CI process, which includes setting up tests and ultimately automating the deployment (very useful).
Another side-effect benefit that often doen't get mentioned is that CI tools like CruiseControl.NET becomes the central issuer of all version numbers for all branches, including internal RCs. You could then enforce your team to always ship a build that came out of the CI tool, even if it's a custom version of the product.
Early warning of broken or incompatible code means that all conflicts are identified asap, thereby avoiding last minute chaos on the release date.
When your boss says "I need a copy of the latest code ASAP" you can get it to them in < 5 minutes.
You can make the build available to internal testers easily, and when they report a bug they can easily tell you "it was the April 01 nightly build" so that you can work with the same version of the source code.
You'll be sure that you have an automated way to build the code that doesn't rely on libraries / environment variables / scripts / etc. that are set up in developers' environments but hard to replicate by others who want to work with the code.
We have found the automatic VCS tagging of the exact code that produce a version very helpful in going back to a specific version to replicate an issue.
Integration is a blind spot
Integration often doesn't get any respect - "we just throw the binaries into an installer thingie". If ithis doesn't work, it's the installers fault.
Stable Build Environment
Prevents excuses such as "This error sometimes occurs when built on Joe's machine". Prevents using old dependent libraries accidentally when building on Mikes machine.
True dogfooding
You inhouse testers and users have a true customer experience. Your developers have a clear reference for reproducing errors.
My manager told us we needed to set them up for two major reasons. None were really to do with the final project but to make sure what is checked in or worked on is correct.
First to clean up DLL Hell. When someone builds on their local machine they can be pointing at any reference folder. Lots of projects were getting built with the wrong versions of dlls from someone not updating their local folder. In the build server it will always be built of the same source. All you have to do is get latest to get the latest references.
The second major thing for us was a way to support projects with little knowledge of them. Any developer can go grab the source and do a minor fix if required. They don't have to mess with hours of set up or finding references. We have an overseas team that works primarily on a project but if there is a rush fix we need to do during US hours we can grab latest and be able to build not have to worry about broken source or what didn't get checked in. Gated checkins save everyone else on your team time.
Our development team (about 40 developers) has a formal build every two weeks. We have a process that in the "build day", every developers are forbiden to commit code into SVN. I don't think this is a good idea because:
Build will take days (even weeks in bad time) to make and BVT.
People couldn't commit code as they will, they will not work.
People will commit all codes in a huge pack, so the common is hard to write.
I want know if your team has same policy, and if not how do you take this situation.
Thanks
Pick a revision.
Check out the code from that revision.
Build.
???
Profit.
Normally, a build is made from a labeled code.
If the label is defined (and do not move), every developer can commit as much as he/she wants: the build will go on from a fixed and defined set of code.
If fixes need to be make on that set of code being built, a branch can then be defined from that label, minor fixes can be made to achieve a correct build, before being merging back to the current development branch.
A "development effort" (like a build with its tweaks) should not ever block another development effort (the daily commits).
Step 1: svn copy /trunk/your/project/goes/here /temp/build
Step 2: Massage your sources in /temp/build
Step 3: Perform the build in /temp/build. If you encounter errors, fix them in /temp/build and build again
Step 4: If successful, svn move /temp/build /builds/product/buildnumber
This way, developers can check in whenever they want and are not disturbed by the daily/weekly/monthly/yearly build
Sounds frustrating. Is there a reason you guys are not doing Continuous Integration?
If that sounds too extreme for you, then definitely invest some time in learning how branching works in SVN. I think you could convince the team to either develop on branches and merge into trunk, or else commit the "formal build" to a particular tag/branch.
We create a branch for every ticket or new feature, even if the ticket is small (eg takes only 2 hours to fix).
At the end of each the coding part of each iteration we decide what tickets to include in the next release. We then merge those tickets into trunk and release software.
There are other steps within that process where testing is performed by another developer on each ticket branch before the ticket is merged to trunk.
Developers can always code by creating their own branch from trunk at any time. Note we are a small team with only 12 developers.
Both Kevin and VonC have well pointed out that the build should be made from a specific revision of the code and should not ever block the developers from committing in new code. If this is somehow a problem, then you should consider using another version management software which uses centralized AND local repositories. For example, in mercurial, there is a central repository just like in svn, but developers also have a local repository. This means that when a developer makes a commit, he only commits to his local repository and the changes will not be seen by other developers. Once he is ready to commit the code for other developers, then the developer just pushes the changes from his local repository to the centralized repository.
The advantage with this kind of an approach is that developers can commit smaller pieces of code, even if it would break a build, because the changes are only applied to the local repository. Once the changes are stable enough, they can be pushed to the centralized repository. This way a developer can have the advatange of source control even though the centralized repository would be down.
Oh, and you'll be looking at branches in a whole new way.
If you became interested in mercurial, check out this site: http://hginit.com
I have worked on projects with a similar policy. The reason we needed such a policy is that we were not using branches. If developers are allowed to create a branch, then they can make whatever commits they need to on that branch and not interrupt anyone else -- the policy becomes "don't merge to main" during the weekly-build period.
Another approach is to have the weekly-build split off onto a branch, so that regardless of what gets checked in (and possibly merged), the weekly build will not be affected.
Using labels, as VonC suggested, is also a good approach. However, you need to consider what happens when a labeled file needs a patch for the nightly build -- what if a developer has checked in a change to that file since it was labeled, and that developer's changes should not be included in the weekly build? In that case, you will need a branch anyway. But branching off a label can be a good approach too.
I have also worked on projects that make branches like crazy and it becomes a mess trying to figure out what's happening with any particular file. Changes may be committed to multiple branches in the same timeframe. Eventually the merge conflicts need to be resolved. This can be quite a headache. Regardless, my preference is to be able to use branches.
Wow, thats an awful way to develop.
Last time I worked in a really large team we had about 100 devs in 3 time zones: USA, UK, India, so we could effectively have 24 hour development.
Each dev would check the build tree and work on what they had to work on.
At the same time, there would be continuous builds happening. The build would make its copy from the submitted code and build it. Any failures would go back to the most recent submitter(s) for code for that build.
Result:
Lots of builds, most of which compiled OK. These builds then started automatic smoke testing scenarios to find any unexpected bugs not found during testing priot to commiting.
Build failures found early, fixed early.
Bugs found early, fixed early.
Developers only wait the minimum time to submit (they have to wait until any other dev that is submitting has finished submitting - this requirement made so that the build servers have a point at which they can grab the source tree for a new build).
Most devs had two machines so they could work on a second bug while running their tests on the other machine (the tests were very graphical and would cause all sorts of focus issues, so you really needed a different machine to do other work).
Highly productive, continuous development with no deadtime as in your scenario.
To be fair, I don't think I could work in place that you describe. It would be soul destroying to work in such an unproductive way.
I strongly believe that your organization would benefit from Continuous Integrations, where you build very often, perhaps for every checkin to your code base.
Don't know if i'll get shot for saying this, but you should really move to a decentralized solution like GIT. SVN is horrible about this and the fact that you can't commit basically stops people from working properly. At 40 people this is worth it because each can continue working on their own stuff and only push what they want. The build server can do what it wants and build without affecting everyone.
Yet another example why Linus was right when saying that in almost all cases, a decentralized solution like git works best in real life teams.
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As recently as several years ago, the developers actually made the builds that went to clients. This was obviously a disaster for reasons too numerous to list.
Then when we started to learn the errors of our ways, we looked for a way to auto-build the entire application on a dedicated build machine. The culture at that time was very averse to bringing in outside tools, so we built our own autobuild system by writing a VB app.
This worked fine for a while, until the project's structure started to change, new projects were added, and we needed to build the application in different ways. Then then weaknesses of our hand-rolled autobuilder became apparent and, over time, increasingly onerous. This disease has progressed now to the point where QA (who owns our build process) can't even maintain the autobuilder because it requires more and more programming skill. Every time we add a project or change something in an existing project, it consumes more developer time just to make it work. There have been days when we were unable to produce a build because the system was broken.
I'm now in a position where I can change this process, and I'm looking to scrap the entire system and put something else in it's place. My goals are:
Have an autobuild system that can run with zero human interaction at a specific time every day. It should be able to gather all the source code, compile all the apps, create the setups, put the finished products on a network share, and possibly trigger the automated testing system to kick in (we use QTP).
The autobuild system should be flexible enough to easily adapt to changes in the project without rrequiring a major overhaul.
It should be simple enough so that QA can own the system and not require developer resources to make changes to how builds are made.
What are your experiences? Can you recommend an autobuild system? Should I have different goals?
I'm currently using CruiseControl integrated with Ant to control project builds. This allows flexibility of build schedules and means you can automate the entire build process fairly easily using Ant scripts. Also, during defect fixing periods you can have CruiseControl set up to watch for source control submissions instead of time periods and build when these occur. This allows developers very quick feedback on defect fixes.
I use FinalBuilder and FinalBuilder Server for nightly builds. It's a bit buggy at times, but if you think it through it's quite easy to create extensible projects that can build X project type, build it's database from change scripts and deploy it to a testing server.
It can also handle all kinds of wierd and wonderful things like ZIPing a nightly build and uploading it to an FTP or creating ISO images automatically.
Definitely look into MSBuild if you're on the Microsoft stack.
Joel is always going on and on about how great FinalBuilder is, so that might be worth a look as well.
We just migrated from a hand-rolled set of Perl scripts to a Buildbot setup. I found it because that's what Google's using for Chrome.
You can do nightlies, or it can integrate with source control to do an isolated test build whenever anybody does a checkin, or a variety of other things. It's also parallel; you can have more than one machine in the build farm, either for specialized duties or just to handle more load.
The entire system is written in Python, so it's platform-agnostic, which is important if you need to do builds on more than one platform. It can do anything you can do from the command line; we have it calling MSBuild for user-mode components, a DDK build for kernel-mode pieces, and running products for unit test builds.
Out of the box it supports most OSS source control tools, but if you're using TFS or something else you may need to modify the package that you install on the slave machines.
I think you are on the right track here.
Whoever looks after your automated build process needs to have a fundamental understanding of how your solution fits together. This doesn't necessarily mean knowing how to write code or architect solutions, but they will require a solid understanding of how the solution compiles, packages itself etc.
You might need to share responsibility for builds between people or teams to accomplish this. I'd say that a daily build is a "team responsibility".
I'd look at establishing a baseline build configuration which can be extended for "special use" builds (besides just building a release version), e.g. internationalized releases, fxCop/Quality Tools config, build + run Unit Tests, continuous integration builds, a build config to run on developer workstations, etc.
Instead, I'd aim to achieve the following:
Automatic versioning, signing etc
Ability to produce verbose output (logging) to help debug build breaks
On that point - it should handle errors properly, capture as much information and log it properly
Consistency - It should work the same way each time to produce repeatable outcomes
Run in a clean, limited access environment
Well commented/documented so that it can be understood by new staff, etc.
Option to generate release notes, compile metrics, produce reports (if this option is available)
Ability to deploy to multiple environments
Support different ways to obtain source code from source control, e.g. by changeset, label, date, etc
As for tool recommendations, I've used FinalBuilder, Visual Build Pro, MSBuild/Team Build, nAnt, CruiseControl and CIFactory plus and good old fashioned batch files.
Each has its pros and cons, I'm not going to make a recommendation except to say that the products with decent UI support were a little bit easier to work with, but at times were far less powerful. If you're working with VIsual Studio, MSBuild is very powerful, but has a somewhat steep learning curve.
As of tools delivered with MS Visual Studio you might want to use MSBuild. Additional Community toolsets for MSBuild will even give you the possibility to checkout code from Subversion and zip output.
We're using it successfully in our company. Projects consists of several solutions with 100+ subprojects. Works like a charm.
Visual Build Pro is nice, if your build machines are Windows. I think this would fill the requirement you have about QA owning the system. But don't get me wrong, it's pretty powerful.
We use CruiseControl.NET and UppercuT (which uses NAnt) to do this. UppercuT uses conventions for building so it makes it really easy for someone to get started by answering three questions (What is the solution named? What is the path to source control? What is your company's name?) and you are building.
http://code.google.com/p/uppercut/
Some good explanations here: UppercuT
We use the Hudson buildbot for for big Java web app building from ant build scripts. Hudson is pretty sweet for our purposes. It has a master/slave setup so builds can be done concurrently (on a timer or on-demand). Slave nodes can be any OS/hardware combo provided it has the needed build tools already on it and is on the network (and won't crash every 10 min).
Full web-based interface including live console output, change logs, artifacts from the build are available across the network including previous builds (if successful). Awesomesauce!
My company has a common code library which consists of many class libary projects along with supporting test projects. Each class library project outputs a single binary, e.g. Company.Common.Serialization.dll. Since we own the compiled, tested binaries as well as the source code, there's debate as to whether our consuming applications should use binary or project references.
Some arguments in favor of project references:
Project references would allow users to debug and view all solution code without the overhead of loading additional projects/solutions.
Project references would assist in keeping up with common component changes committed to the source control system as changes would be easily identifiable without the active solution.
Some arguments in favor of binary references:
Binary references would simplify solutions and make for faster solution loading times.
Binary references would allow developers to focus on new code rather than potentially being distracted by code which is already baked and proven stable.
Binary references would force us to appropriately dogfood our stuff as we would be using the common library just as those outside of our organization would be required to do.
Since a binary reference can't be debugged (stepped into), one would be forced to replicate and fix issues by extending the existing test projects rather than testing and fixing within the context of the consuming application alone.
Binary references will ensure that concurrent development on the class library project will have no impact on the consuming application as a stable version of the binary will be referenced rather than an influx version. It would be the decision of the project lead whether or not to incorporate a newer release of the component if necessary.
What is your policy/preference when it comes to using project or binary references?
It sounds to me as though you've covered all the major points. We've had a similar discussion at work recently and we're not quite decided yet.
However, one thing we've looked into is to reference the binary files, to gain all the advantages you note, but have the binaries built by a common build system where the source code is in a common location, accessible from all developer machines (at least if they're sitting on the network at work), so that any debugging can in fact dive into library code, if necessary.
However, on the same note, we've also tagged a lot of the base classes with appropriate attributes in order to make the debugger skip them completely, because any debugging you do in your own classes (at the level you're developing) would only be vastly outsized by code from the base libraries. This way when you hit the Step Into debugging shortcut key on a library class, you resurface into the next piece of code at your current level, instead of having to wade through tons of library code.
Basically, I definitely vote up (in SO terms) your comments about keeping proven library code out of sight for the normal developer.
Also, if I load the global solution file, that contains all the projects and basically, just everything, ReSharper 4 seems to have some kind of coronary problem, as Visual Studio practically comes to a stand-still.
In my opinion the greatest problem with using project references is that it does not provide consumers with a common baseline for their development. I am assuming that the libraries are changing. If that's the case, building them and ensuring that they are versioned will give you an easily reproducible environment.
Not doing this will mean that your code will mysteriously break when the referenced project changes. But only on some machines.
I tend to treat common libraries like this as 3rd-party resources. This allows the library to have it's own build processes, QA testing, etc. When QA (or whomever) "blesses" a release of the library, it's copied to a central location available to all developers. It's then up to each project to decide which version of the library to consume by copying the binaries to a project folder and using binary references in the projects.
One thing that is important is to create debug symbol (pdb) files with each build of the library and make those available as well. The other option is to actually create a local symbol store on your network and have each developer add that symbol store to their VS configuration. This would allow you to debug through the code and still have the benefits of usinng binary references.
As for the benefits you mention for project references, I don't agree with your second point. To me, it's important that the consuming projects explicitly know which version of the common library they are consuming and for them to take a deliberate step to upgrade that version. This is the best way to guarantee that you don't accidentally pick up changes to the library that haven't been completed or tested.
when you don't want it in your solution, or have potential to split your solution, send all library output to a common, bin directory and reference there.
I have done this in order to allow developers to open a tight solution that only has the Domain, tests and Web projects. Our win services, and silverlight stuff, and web control libraries are in seperate solutions that include the projects you need when looking at those, but nant can build it all.
I believe your question is actually about when projects go together in the same solution; the reason being that projects in the same solution should have project references to each other, and projects in different solutions should have binary references to each other.
I tend to think solutions should contain projects that are developed closely together. Such as your API assemblies and your implementations of those APIs.
Closeness is relative, however. A designer for an application, by definition, is closely related to the app, however you wouldn't want to have the designer and the application within the same solution (if they are at all complex, that is). You'd probably want to develop the designer against a branch of the program that is merged at intervals further spaced apart than the normal daily integration.
I think that if the project is not part of the solution, you shouldn't include it there... but that's just my opinion
I separate it by concept in short