How to setup source control with multiple products all dependent on a single class library

Question

I am the CTO and sole developer for my company. I'm getting ready to hire our first developer and possibly a second within the next 6-12 months. I'm embarrassed to say that I've never used source code control as part of my workflow. I guess being a 1-member development team has allowed me to be a bit lazy. It's not that I haven't wanted to, I just have a bit of a mental block about how to get started with it.

We have 5 web applications that I build and maintain. We use ASP.NET, and each web app references a single .NET Class Library (DLL) that has been copied into the "bin" folder for each app. I've been developing with a single Visual Studio "solution" that includes the class library and all of the web apps. A bit bloated, I'm sure, but this method has made it easy for me to minimize mistakes by enabling me to do global find and replace operations on all of my apps (and the class library) at the same time.

I realize that implementing source code control is a big change to my workflow by itself, but also introducing another developer into my process has me a bit overwhelmed. I'm looking for some assistance on how to develop a workflow that will enable my small team to move quickly without cumbersome processes. I'd like to avoid discussions about which SCC system to choose (we're going to use Mercurial). I'm more interested in discussing the structure and workflow aspects of this.

Here are the questions I need help with:

1. Should I split up each app into a separate "project" or keep them all together so we can continue to benefit from global find-and-replace operations when necessary. I'm worried about splitting them up because of the class library situation (see #2).

2. If splitting up the apps into separate projects, I'm not sure how to proceed with the class library that each project needs a copy of. For example, let's say that the changes to one of the apps (call it "project 1") requires a change to the class library... if the class library is in a separate project (call it "project 2"), it seems "messy" to me that project 1 would be dependent on the latest changes in project 2 in order to work properly. Or, do you simply make your changes to project 2 (the class library), check them in, and then copy the newly compiled dll into project 1 (but shouldn't the new copy of the dll being copied into project 1 be recorded in the SCC somehow). I'm getting confused even as I write this...

Thanks in advance for your help.

Answer 1

First, congratulations on deciding to finally use source control. I know changing your habits can be frustrating but in the long run I'm sure you'll see the benefits.

1. There's nothing wrong with a solution that has multiple projects in it. I generally keep mine to about 10 but that's simply to improve load times. If keeping them together works better for you, leave it that way. Usage of source control won't have any affect on this.
2. As far as the class library, I think what you need to do is change the way you go about making changes to the library project rather than how you use the projects that reference it. Implement unit testing on the library project to enforce backward compatibility so you know that dropping the latest version of the library won't break your app. You'll likely find this won't be true a few times but as you develop more unit tests to handle edge cases this will happen less and less.

Answer 2

You can have multiple projects in a single Visual Studio solution. What I've done in the past is to have both the ASP.NET project and the class library project in the same solution. You can have your ASP.NET project reference the class library project (Add Reference and then go to the Projects tab to show other projects in the same solution). That way, whenever you change the class library, the ASP.NET application will be build using the latest version of the class library. You can setup multiple solutions - one for each ASP.NET application with each solution including the class libary project.

You could also setup one large solution with all of your ASP.NET projects as well as your class library but that may get a bit hard to work with, especially with multiple developers working on the different ASP.NET pages.