How to benefit from SVN in web development - eclipse

I am managing the development of currently two different web applications of which one will roll out in beta testing before sunday.
I have some previous experience from SVN usage, after playing around a few hours with TortoiseSVN locally on a XP machine, but I never really got the hang out of it to be honest.
However, it feels like it's about time to rethinking SVN and really try to give it an honest chance. I would at least sleep alot better if I know that versioned backups of each file were available and it was easy to roll back changes to an web applications whenever something hits the fan. Especially as the app grows bigger.
I currently work exclusively with PHP in Eclipse and deploy all files for the beta environment through FTP.
I have read most posts here about using Eclipse with SVN plugins, but I really doesn't understand how the workflow practically would look when SVN is used.
Do I check in every morning to my repository, do what i do best, and at the days end commit all changes?
How would sync be kept between local file structure, SVN repository, and multiple environments (live env., testing env., etc)?
Tell me about how your workflow looks when using SVN!

You may want to start by going through the free online book:
Version Control with Subversion published by O'Reilly Media
Chapters 1 and 2 go through the fundamental concepts and the basic usage of Subversion. Then the remaining chapters explore more advanced topics.

Here's my steps with SVN for what I do:
Branch to work on bug/feature -> When starting to work on a bug or feature, I create a new branch taking the head revision of the code so that I'm in my own sandbox of sorts.
When I've fixed the bug or finished the feature, then comes the switch back to the main branch and merging in the fix so that it becomes part of the next code push into either dev clean or test. While this isn't exactly simple, it isn't as painful as one may fear.
Periodically, there are other things to do:
Clean up old branches -> As features and bugs get done, sometimes it is worth going back and pruning the work done so that the folder doesn't become huge in the Repo-browser.
Update code on my box -> Sometimes I'll go a little time between features and bugs, though I'd still like to keep the code on my machine up to date as much as possible.

Hmm,
If I may mention the little app I'm working on currently, dashy: http://www.mirios.com.au/dashy, it handles what you're concerned about from the deployment/configuration side (rolling back changes, handling configuration of multiple environments: dev/staging/live, etc) and is suitable for Windows + SVN only, at the moment. (Getting started with it, however, will be slightly involved, and the documentation isn't particularly complete, though it gives an idea).
As to how to use SVN in general, well, you have a build server, and you use a CI system to to automated builds, then you commit to your CI server (We use CruiseControl.NET, Hudson could do it as well). Further to this, you generally update in the morning, to check if anyone in the team made relevant changes, and use branches and tags where appropriate.
It's kind of complicated, (but not really) and once you get started and get everything installed, life should be quite good (whether or not you use dashy).

Related

How should we tackle a big change in our application?

We have this huge application that has 18 projects in our source control (VSS).
Whenever we are working on small changes everything is fine because each developer has a set of a few files checked out to himself, and hopefully no one is going to need them until they are checked in (in about 4 to 8 hours).
But when we want to work on big changes a developer keeps so many files checked out for some days and make it hard for others to do their assigned tasks.
Here's a scenario for example:
Last week we wanted to implement a feature that will fetch every list in our application using a paging mechanism. Therefore we should change the UI, business and data access layers.
There's a developer assigned to this task, she's checked out a lot of files, and she's blocking other tasks.
How should we plan to develop these kind of features?
Switch to a better Version Control System. VSS suffers from design issues and its hard lock principles. Subversion is available for free and can be used for large scale application development. Branching and tagging are cheap operations and there is no hard lock.
Your company will definitively live better with Subversion. Try it out!
Server Easy to setup on what system ever (Windows/Linux)
TortoiseSVN Client for Windows that integrates within Windows Explorer
SVN Manual Read at least the first few chapters
There are many other alternatives but VSS is a pain in large scale development. As there is a better free solution available, why stick to a vendor?
If upgrading to a real VCS isn't an option right now, have the person doing the major feature download a local copy of everything and then make his changes outside of version control. Merge it all at once (over a weekend or something in case it gets complicated).
This doesn't help the developer who will need version control while making the "big changes"
Well, you do what you gotta do with the tools you've got. He could always install a modern VCS like git which works locally. Just check the entire baseline into git (minus history) and go.
VSS sucks, migrate to a real SCM, microsoft will probably help you seamlessly upgrade to TFS which doesn't have this problem. Or migrate to any one of FOSS SCMs like subversion, but the transition will probably be harder (but may be cheaper).
Have you considered sharing and branching? Also, you can allow multiple checkouts with users who have experience. In your case of making a large application change, I suggest labeling then creating a branch. If something happens to "big changes", you will not the production version. You can make your quick fixes in the released code then merge them into "big changes" once it is ready. Check the help topic "Sharing and Branching".
Use a version control system that works in merge mode (optimistic), not in lock mode.
Merge mode is optimistic is that it assumes changes will usually not be made in the same place. If it happens in the same place then it is usally easy to resolve.
An example of a version control system that can work in merge mode is CVS. It is outdated now, but others exist.
SVN is the answer to your problems. I have used it and its a breeze to learn/work with it. But there are a few new kids on the block. Try GIT. I have been hearing a lot about it althought havent had a chance to try it
VSS is just an old story, we use Subversion (server) and TortoiseSVN (client) now. (That's just based on our preference)
By the way, migrating to other version control / source control - only - will not solve your team issue. The problem is about communication. If she can't communicate with the others and stay with her habit (working with a lot of files without checking them in), she will put your team down, you must let her know how to work with team using version control. If not, she will put you into "Merge" problems when using Subversion. ^^
You already got the advice about changing to a usable VCS.
Above that, you and the developers should train to break the big changes into smaller ones. I'd consider about 10 commits per day and full time developer a normal rate. It makes the locks much less painful.
The principle should be: make the smallest possible change that brings you toward your desired state and works (as in the software compiles and passes all tests).
In the case you sketched out. Adding a parameter to one layer, and changing all calls to that layer (possibly with a dummy value) would be one change. Actually using that value, would be another change.
This should result in much less files locked for a much shorter period.
Long-term, you'll want to migrate to another VCS. As others have mentioned, consider either open source or TFS if you want to stick with MS. (We use TFS, but I'm not going to sing its praises - it's OK.) As AMissico mentioned, branching will help with any VCS that supports it. Learning to use branching effectively is not trivial, and will require study and/or training.
Continuous Integration will also help. TeamCity is what we use, and it's relatively simple to set up. See FeatureBranch.

Ideas on setting up a version control system

I've been tasked with setting up a version control for our web developers. The software, which was chosen for me because we already have other non-web developers using it, is Serena PVCS.
I'm having a hard time trying to decide how to set it up so I'm going to describe how development happens in our system, and hopefully it will generate some discussion on how best to do it.
We have 3 servers, Development, UAT/Staging, and Production. The web developers only have access to write and test their code on the Development server. Once they write the code, they must go through a certification process to get the code moved to UAT/Staging, then after the code is tested thoroughly there, it gets moved to Production.
It seems like making the Developers use version control for their code on Development which they are constantly changing and testing would be an annoyance. Normally only one developer works on a module at a time so there isn't much, if any, risk of over-writing other people's work.
My thought was to have them only use version control when they are ready to go to UAT/Staging. This allows them to develop and test without constantly checking in their code.
The certification group could then use the version control to help see what changes had been made to the module and to make sure they were always getting the latest revision from the developer to put up on UAT/Staging (now we rely on the developer zip'ing up their changed files and uploading them via a web request system).
This would take care of the file side of development, but leaves the whole database side out of version control. That's something else that I need to consider...
Any thoughts or ideas would be greatly appreciated. Thanks.
I would not treat source control as annoyance. See Nicks answer for the reasons.
If I were You, I would not decide this on my own, because it is not a
matter of setting up a version control software on some server but
a matter of changing and improving development procedures.
In Your case, it might be worth explaining and discussing release branches
with Your developers and with quality assurance.
This means that Your developers decide which feature to include into a release
and while the staging crew is busy on testing the "staging" branch of the source,
Your developers can already work on the next release without interfering with the staging team.
You can also think about feature branches, which means that there is a new branch for every specific new feature of the web site. Those branches are merged back, if the feature is implemented.
But again: Make sure, that Your teams agreed to the new development process. Otherwise, You waste Your time by setting up a version control system.
The process should at least include:
When to commit.
When to branch/merge.
What/When to tag.
The overall work flow.
I have used Serena, and it is indeed an annoyance. In addition to the unpleasantness of the workflow overhead Serena puts on top of the check in-check out process, it is a real pain with regard to doing anything besides the simplest of tasks.
In Serena ChangeMan, all code on local machines is managed through a central server. This is a really bad design. This means a lot of day-to-day branch maintenance work that would ordinarily be done by developers has to go through whomever has administrator privileges, making that person 1) a bottleneck and 2) embittered because they have a soul-sucking job.
The centralized management also strictly limits what developers are able to do with the code on their own machine. For example, if you want to create a second copy of the code locally on your box, just to do a quick test or whatever, you have to get the administrator to set up a second repository on your box. When you limit developers like this, you limit the productivity and creativity of your team.
Also, the tools are bad and the user interface is horrendous. And you will never be able to find developers who are already trained to use it, because its too obscure.
So, if another team says you have to use Serena, push back. That product is terrible.
Using source control isn't any annoyance, it's a tool. Having the benefits of branching and tagging is invaluable when working with new APIs and libraries.
And just a side note, a couple of months back one of the dev's machine's failed and lost all his newest source, we asked when the last time he committed code to the source control and it was 2 months. Sometimes just having it to back up stuff when you reach milestones is nice.
I usually commit to source control a couple of times a week, depending if I've hit a good stopping point and I'm about to move on to something different or bigger.
Following on from the last two good points I would also ask your other non-web developers what developmet process they are using so you won't have to create a new one. They would also have encountered many of he problems that occur in your environment, both technical using the same OS and setup and managerial.

What OSX/XCode version control system should I use for iPhone development?

I've been developing my first iPhone app part-time and would like to start using a more rigorous form of version control than I've been using over the past four months, i.e. copying source code folders to another directory and time stamping them.
I've used SourceSafe and Team Foundation System but I don't have a good idea of what version control systems (VCS) are available for the Macintosh. I've seen ads on SO for a Subversion front end but would like some other options.
Here's a list of my initial requirements:
Runs locally under OS X Leopard 10.5.7
Integrates with XCode 3.1.3 (if no integration, user-friendly interface)
Basic VCS features - check-in comments, branching, pinning
Advanced VCS features like build automation or reports would be nice but not critical at this time
Ability to handle multiple developers down the road (6-12 months)
Thanks in advance for the help.
Mercurial would be my pick for version control for a project starting as a solo project if you don't want to set up a dedicated server. Mercurial requires no server because it's a distributed VCS, every working copy is also a complete repository, so once you've installed Mercurial you are ready to go, just type 'hg init' in the root directory of your project and you're off.
It's perfect for working alone or with a small number of developers (i.e. no IT staff or sysadmins available), it has a utility that lets you quickly set up a temporary server for your local repository so when you meet up with people it's easy for them to clone the repository or share changes. You can also just give people copies of your repository over email or USB key or copy them over the network or whatever and reconcile changes to the copies against each other later.
For me Mercurial made the difference between actually using a VCS for personal projects and just giving up because it's too much trouble. Setting up a Subversion server locally isn't a huge deal but it's still enough trouble to make me not bother, and if you really want to be thorough you'd want to think about how to do proper backups, etc. With Mercurial at any point you can just back up your working copy to other media and you have a backup. I don't know if this really makes sense but Mercurial is a VCS that you can use casually and informally thanks to the distributed nature.
No Xcode integration, but having used various VCS' with and without integration I don't think it's very important as long as good clients are available. These days I've mostly settled on just going command line and it's refreshing.
Perforce, IMO, is right out. Aside from being a commercial product it is obnoxious beyond belief. It requires you to be connected to a server at all times or things become a major pain in the ass. So if you just want to work on stuff from multiple machines in multiple locations or if you want to have people on the project that won't be on the same network all the time it's going to suck. Perforce just constantly beats you over the head with the fact you are using Perforce, no other VCS I've used is so in your face and annoying.
Git is another option with a similar feature set to Mercurial that might be worth looking at. In my case I also do Windows stuff and Git's Windows support is supposedly crap so I went with something that works on all my platforms.
Build automation IMO is the build server's job, not the VCS' job, so if you want build automation find an appropriate build server.
SVN or Subversion is included with Xcode and is well integrated with it. As you grow to have bigger needs, you can use third-party Subversion servers and use the same SVN support over the network. If you don't like SVN, I think XCode supports CVS too.
If you're looking for something adequate, cheap, and expandable, then just mosey on over to the SCM menu of XCode, and check out what's already there. If you need help setting up SVN, just comment.
IT looks like subversion would be your best choice for XCode as there is already some guidence on getting that up and running with XCode here. Subversion addresses all of the features you are speaking of. Pinning specifically is a feature of Source Safe; however subversion can do tagging. Build automation is not a feature of a source control system, but source control systems are typically used in continuous integration server scenarios. I have not used it but from what I understand Hudson is a continuous integration Server which is gaining popularity and momemtum. You can find more information on Hudson here and here
SubVersioN (SVN) fulfills (most of) your requirements.
I'd also put in a vote for subversion since XCode supports it natively. I've been using it myself and have been very happy.
However I'd question your requirement to run the server locally. Sure, you can do that no problems with subversion. But wouldn't you be nervous about your hard disk failing?
I've been using Beanstalk to host my source code. It's free for up to 3 developers, you'll be able to upgrade your account once you grow, its fast and it's SAFE.
I just looked in Xcode (3.2, though, so it may not be exactly the same) and the options for source control integration are subversion, CVS and perforce.
Outside of Xcode, there are a couple of very nice GUI clients for subversion for OS X.
Subversion would be a good place to start, it seems.
All the cool kids are using distributed VCSes these days, apparently. You might want to spend half an hour reading up on git or mercurial (hg - my preference). There's no direct integration with Xcode, but they're easy enough to get into.
Perforce is now free for up to twenty users, but will be expensive after that. You might want to check it out, however. Xcode no longer supports native Perforce integration, though there are scripts and a plugin.

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I have the opportunity to give a formal presentation to my boss about anything that benefits the company. My idea is to adopt source control in my workplace. I have been using Mercurial to manage my own project at work, but the rest of the team does not have a formal source control system in place. Unfortunately, I'm not very good at presenting ideas.
So, can you guys tell me why developers MUST use source control? Additionally, why would you choose any tool except Visual SourceSafe? I don't have experience using VSS, but he is likely to ask why we wouldn't just use Microsoft's tools.
I want to hear opinions from the many smart programmers here! My preferred options are SVN or mercurial. Both seem to have good support for their Windows versions, and both are less archaic than CVS. Also, as a self-declared open source disciple, I would prefer to suggest an open-source tool. :)
Thank you!
Edit: To make it short, generally, current practice for other developers is copying folder, tag with date and maybe record on their own. You get the picture. What if my boss says "if it works, why fix it?"
Let's compare two examples, one development environment that uses source control, and one that doesn't.
A: Does Use
B: Does not Use
Scenario 1: A project is requested, completed, and rolled out
A + B) Programmers develop the project internally, when it's completed, push it out to testing, and then deliver to the client (whoever that may be)
Not much difference, in the big picture
Scenario 2: After a project is released, the client decides that they don't want feature X
A + B) Developers remove the code that the client doesn't want, test, and deliver.
Again, not much difference.
Scenario 3: Two weeks later, the client decides that they actually DO want feature X
A) Developers reintegrate the code they took out in 2 back into the normal development tree, test, and deliver.
B) The developers search for the old code on their personal machines, the file server, and backups. If they find the code, they must manually reinsert each file. If they do not, they probably have to recode that entire feature.
It's easy to get old code that you took out for one reason or another
Scenario 4: There's a strange bug in the system where a function is supposed to return a boolean result, but always returns false. It wasn't like that two weeks ago.
A) Developers examine all the old versions of the software, and figure out that a return false directive isn't in the proper scope - it's executing inside a loop instead of outside.
B) Developers spend weeks trying to figure out what the problem is. Eventually, they notice the return on the wrong line, and fix it. Not having source control means they had to examine each and every file that was executed, rather than finding the differences from when it was working and now.
Scenario 5: Someone breaks the build. It gets past testing and is only noticed weeks later.
A) The team examines the commit history, finds out who broke the build, makes that person fix it and buy the team dinner.
B) The team has to go back through the entire project to find the error, but can't figure out who put that code in. Developers blame each other, and the team dynamic fails.
It's easy to see who committed what, when, and why.
Use source control because neither you nor your team are perfect. The primary function of source control is to ensure that you have a complete historical record of your development process. Having this record, you have the ability to confidently branch out with "experimental" versions, knowing that if the experiment fails, you can back up to an earlier version.
In addition, a good source control system like svn will permit multiple developers to work on the same file and provide powerful tools for reconciling the differences that each introduces.
Simply - so you have a true history of the code - to investigate changes (reasons for bugs), revert to versions, audit, etc. Backup isn't enough - you simply have a copy of the current picture. Ever change a file and wish you could remember what you did?
You have to use Source Control for these reasons
1) You can rollback to any version
2) Different developers can work on the same files
3) All developers, will have access to the same code base
4) You can track changes
5) You can rollback changes that don't work
6) Source control is the basis of continuous integration and helps massively with TDD
7) If you don't use source control, you will slowly go mad as files get lost/overwritten and nothing works as it should
VSS is not the worst SCC application, I used it for years and grew to hate it, but it does work, is simple, and many people know it.
Here's a simple real-life example.
A few years ago, my boss says, "Feature XYZ used to work, and now it doesn't. No one knows what happened. Can you fix it?"
Now I've never worked with feature XYZ before. So fixing it would involve a lot of flailing around trying to figure out what it does.
But we have source control! So I do this:
Create a test script to test feature XYZ: "Click here, type this, click there, etc."
Get current version. Build. Test. Feature XYZ is broken.
Get version from a week ago. Build. Test. Feature XYZ works.
Get version halfway between those two. Build. Test. Feature XYZ works.
Get version halfway between previous one, and current one. Build. Test. Feature XYZ is broken.
I kept doing this binary search until eventually I hit the point of change: version 145 (we'll say) had the feature working, but version 146 had it broken. Then I just did a compare between those two versions to see what changed. Turns out our technical lead (sigh) had checked in code that changed functionality, but also introduced a side effect that broke feature XYZ.
So I removed the side effect, tested...and lo and behold, feature XYZ worked again.
Without source control, you can never do this. You'll have to flail around, changing one thing or another, hoping to magically hit on the thing that makes feature XYZ work again.
With source control, you just test your way through the versions, pinpoint the exact code that caused the problem, and fix it.
Microsoft (MSDN) has a good article on the benefits of source control.
http://msdn.microsoft.com/en-us/library/ms173539.aspx
There are also lots of good questions here on SO as to the pros and cons.
What are your pros and cons of git after having used it?
Subversion is very popular, but Git is going to be the "next big thing" in the source control world.
It seems to me that most people have covered the major feature of source control but one of the biggest positives is skipped over. These are:
Branches
Without a source code repository it is impossible to create branches (or copies/stream/etc.) of your code for particular purposes. Not being able to create and merge branches is one of the biggest things that disqualifies VSS from being a real source code control system. Some of the purposes of a branch include:
Bug Fix
Sometimes you need to resolve a bug and do it in a place away form the mainline or trunk version of your code. This may be to resolve a problem in the testing environment or any number of reasons. If you have a version control tool you should be able to easily make a new branch (something VSS sucks at) to fix the bug and be able to merge it back into the mainline code if necessary
Maintenance Release
This could be much the same as a bug fix but done after code has been released to production. Examples would be for fix packs, service releases, etc. Again, you want to be able to merge the changes back into the trunk if necessary
New Feature
Sometimes you need to start development of a new version while maintaining your current code. For example you release and maintain v1.0 but need to start work on v2.0 while maintaining v1.0. Branches help resolve this situation
Tagging/Labeling
Another thing source code control systems do is make snapshots of the source code at a particular point in time. These are called labels in VSS, tags in subversion, etc. By creating these on a regular basis and linking them to some substantial milestone in your project it then becomes possible to determine what exactly has changed in your code between releases. This can be important for auditors but also in tracking down the source/scope of an issue. VSS also gets a fail here because VSS only versions the files, not directories. This means it is impossible to re-create a previous version of the system if you rename/move/delete files or directories in the repository (something that happens a lot if you refactor). Good source code control systems like Subversion do just this.
I suggest using SVN, because:
Source control gives you excellent history. You can see where what changes have been made, thus providing a great way to see what's changed over time (even better if you fill out the submit summary each time)
To the developer, it provides an excellent fallback if something goes horribly wrong. You can revert changes to a file back to any point in its history, so you can try out that mod you wanted to make, and if it doesn't work, roll it right back easily.
It provides a central repository that is much easier to back up than running around to different developers' computers.
It allows you to branch a project off in a different direction - useful for specializations and customizations.
It enables more than one developer to work together on the same project, and the same source, by letting you merge and otherwise manipulate changes to one central copy.
I suggest NOT using VSS - see this page for reasons:
http://www.highprogrammer.com/alan/windev/sourcesafe.html for more reasons.
If the current process is copying a folder and giving it a date, isn't that so that you get some sort of development history, so isn't that basically a simple form of source control?
So to answer any criticisms about source control, you're already doing it. Now you just need to point out the weaknesses in the current system and suggest a better one.
Why do you need to re-invent the wheel when people have really thought about a lot of the complex scenarios which can occur during development and developed the tools which let them handle them.
What you're currently doing is very fragile and will fall over if any sort of complex scenario comes up, at which point you'll have to expend a lot of energy working out how to do something that the tools already do. VSS is better than what you're doing, but doesn't have the very useful conventions that SVN, git or mercurial has which allows multiple projects to live together in a well organised manner - I'm talking branches, tags and merging, both of which are fragile and basically a nightmare under vss.
SVN does have plugins for visual studio. Some are free. But I find that tortoise-svn just eclipses anything else. The only benefit I find with a plugin is that new files get added to svn automatically.
So, weaknesses of your current system:
If you have to make a change to a file, you are likely to overwrite or be overwritten by the other dev's changes. You may not even notice this.
If you have to remember which files you've changed to copy them over some 'master' copy, you're likely to miss one at some point.
Good luck ever finding any documentation about when you made a change and why.
How could you ever build a stable automated build system on your current system? Cruise control and hudson work really well, you're hobbling yourself
VSS doesn't group changes to multiple files together very well. Everything modern does this extremely well and with atomic consistency.
VSS branch and merge support is awful. When we used it we ended up bracketing every change with comments in source code and manually copying code around rather than relying on VSS merge.
It's going to be very hard, near impossible in your current system, to have some version of the code in live maintenance and some other, later version, in heavy development. Think about what's needed to keep two projects in sync like this, you'll need a good tool. SVN can do it, git can do it really well.
That might be enough to go on with, can do more.
Having some version control system helps in any, many cases:
Single developer, single branch
The most basic task that each version control system has to perform perfectly if it wants to call itself version control is to be able to go back to specified version of a project. If you made mess of things, you can got to previous version. You can examine some previous version to check how it was done then (for example how it was before refactoring, or before removing some code/file).
Version control systems take much less disk space compared to simply saving backup copies with specified date, because they use deltaification (storing only differences from previous version) and compression. Usually backup systems are means to store last N versions of a project, sometimes with N=1 (only previous version) while version control systems (VCS) store all the history of a project. Knowing Murphy a while after deleting Nth last version you would realize that was the version you want to examine.
Additionally going back to some last version is easy and automated. You can also examine how single file looked like at some past version, and you can get differences (in diff format) between current state and some past version. You can also tag (or 'label') versions, so you can refer to past version not only by date, or by being nth version from current one, but also by symbolic name, for example v1.2 or v1.2-rc0.
With version control system you can examine history to remind you why (and how) some piece of code (some part of a given file) arrived at current state. Most VCS allow to examine line-wise history of a file, i.e. annotating each line of a file when it was changed, in what commit, and by whom (the command is named annotate, blame or praise depending on VCS). In some VCS you can search history for a version (revision) which introduced given fragment of code (e.g. called 'pickaxe search' in Git, one of VCS).
For this feature to be really useful you have to maintain some discipline: you should describe each new version (each new revision / each new commit) writing down why the change was made. Such description (commit message) is very useful, but it doesn't have natural place in backup system.
This feature of course is even more useful if you are not the only developer...
Using version control system allows for alternate way to find bugs in the code, namely by searching history to find version which introduced bug: bisectiong history. When you find revision which introduced bug, you would have limited (in best case: very limited) area to search for bug, because bug has to be in the difference betwen last working version and first version with a bug. Also you would have description of a change (a commit message) to remind you what you wanted to do. This feature is also called sometimes diff debugging. Modern version control systems (VCS) have support for automated (or semi-automated) searching the history by bisecting it (dividing history in half, finding which part contains bug, repeat until single responsible version is found), in the form of bisect (or similar) command.
For this feature to be really useful you have to maintain some discipline: you should commit (save changes / put given state in version control system to remember) single change, dealing with only one feature, with only small difference from the previous version; i.e. commit often.
Most version control systems offer various hooks which allow for example for automated testing, or automated building of a product... or simply reminding you that you do not follow coding standard (coding guidelines).
Single developer, multiple branches
Version control systems allow to create multiple alternate parallel lines of development, called branches (or streams, or views). Common case is having development branches, i.e. having separate branch for unstable development (to test new features), separate branch for stable (main, trunk) version which is (or should be) current working version, and one on more separate maintenance (fixup) branches.
Having maintenance branches allow you to do bugfixes and generate service packs / minor version with corrections to some released version, without need to worry about interference from the new development. Later you can merge maintenace branch into stable, or pick bigfix from maintenance branch into stable and development branches (if further/other development didn't fix bug independently).
Modern VCS (here modern means that both branching and merging branches is easy) allow to go a bit further, i.e. generate separate branch for working on a separate feature (so called topic branches). This allow you to switch between working one one feature to working on other feature (and not only switch from eveloping new feature to working on urgent requested bugfix).
If you are developing your product based on source of some other (usually third party) product, you really should use vendor branches to be able to easy integrate new version of a product from vendor with the changes you made. Admittedly this is no longer purely "single developer" case.
Multiple developers
Using version control systems brings even further advantages if there are more than one developer working on the same project. VCS allow for concurent (parallel) development without worrying that somebody would overwrite your changes, or does not take your changes into account. Of course using version control system is no substitute for communication.
All of the above features are even more important in the multiple-developer case: examining who generated given change, who last changed the code (aka. who broke the build), finding a bug in code not written only by you.
Simple: If the code is not in source safe, it doesn't exist
Subversion is free and better than VSS but VSS is definitely better then nothing.
Before you say anything, find out why your company is not using source control.
Once you know why, it is easy to come up with scenarios where source control can help.
Long discussion on why you should absolutely have source control:
Is Version Control necessary for a small development group (1-2 programmers)?
My comments from that thread:
You always, always want to have some
sort of Source Control even if you are
working on a project by yourself.
Having a history of changes is vital
to being able to see the state of a
codebase at any given time. There are
a variety of reasons for looking back
in a project history which range from
just being able to rollback a bad
change to providing support for an old
release when the customer just wants a
patch to fix a bug rather than
upgrading to a newer version of the
software.
Not having some sort of source control
is pure insanity.
As far as VSS goes - it's certainly better than nothing. It's definitely not the best source control and it's very dated, but the fact it that it continues to do the job for an awful lot of companies out there.
If your boss is determined to stick with Microsoft tools, go for Team Foundation Server instead of VSS. It's a much better system than VSS and it has nice features like integrated bug tracking.
Take it from me, VSS blows. It's basic file storage w/ history. Anything is better than VSS and VSS is better than nothing :)
So, can you guys tell me why
developers MUST use source control?
It provides one method for an entire
team to use; everybody operates under
the same 'ground rules'.
Changes are
orderly vs. chaotic, saving
development time.
The ability to track
changes promotes accountability and
makes it easier to find the right
persom to solve problems in the
materials maintained.
A list of exact
changes made can be generated quickly
and easily, making it easier to
advise users of the information on
how it has changed from version to
version.
It is easy to 'roll back' to
an earlier version of the
information, if a serious mistake was
made during a change.
Source Control is like insurance! You hope you never need it, but are glad you have it when you do!
Why do a formal presentation?
Assuming the team size is at least two, do a real-world example: Let two (or more, the more the better) people get the code, make their changes and show what it takes to integrate all those changes using whatever non source control means you use.
Then do the same scenario using the source control.
The amount of time and pain you save by using source control will speak for itself.
Stick to the bottom line, explain how it relates to money and your boss will probably listen.
If you are only one programmer, I'd say the main argument is the reduced chance that you will waste time (and therefore money) fixing simple mistakes, trying to rollback code that turned to be the wrong idea etc.
If you are more than one programmer then the above goes twice plus it's the only sane way to be able to work together on the same codebase without wasting even more time waiting for eachother,
Visual Source safe is better than nothing but there are free options that are better in almost every respect. If your boss needs a presentation to understand why source control is essential he might not care what tool you use once he has been enlightened. That you have experience with other tools and not vss again relates to the bottom line so that might suffice.
Why shouldn't your team adopt source control?
Even as a solo developer, I use source control. In a modern software development environment, I can think of few if any reasons why you would not use source control. It is more surprising that you don't already have it. The question strikes me as something like house painters asking "Why should we adopt the use of ladders. You know, ladders don't get the house painted - brushes do."
I'm really sorry but if you actually have to argue for [the formalization of] source control in a development environment, you're in a hopeless situation. If your boss actually needs to be convinced that source control is a worthwhile endeavor, your boss is simply not suitable to be a manager of a group of software developers. In order for someone to effectively manage, they really need at the very least a basic understanding of the landscape. I can't even imagine what's going to happen when you actually need to argue for something that's worth having an argument and doing a presentation over.
Developing without source control is like driving a car without breaks. You lose the ability to do seamless concurrent development, you lose your code getting backed up in working copies, you lose the ability to do historic research via code annotations, you lose the benefit of seeing the context and comments that accompany discrete changes, you just lose, period. Using source control is so obvious and has so many benefits, it's shocking that you'd have to justify it.
At work, we use subversion, but some developers (myself included) use Git locally via the git-svn bridge. For personal work, I use Git.
Because:
It will reduce costs - Developers will have to spend less time checking an item in/out of a real VCS than their current ad-hoc approach.
It will protect the organization's intellectual property - this should be the most important consideration for any software company (other than data...). You are payed to create software - shouldn't it be accessible in its entirety?
It will provide quicker, more reliable and straightforward backup mechanisms - all VCSs have built in dumping capabilities. These tend to be more mature than a simple file copy.
It will act as a communication mechanism between developers - depending on the version control system you may use comments/labels/checkout status to determine if someone else has worked on a file, if it has been promoted to production, if it has a corresponding support ticket number etc.
It streamlines development - the ability to compare versions of files as well as the other mechanisms will be beneficial to your company period.
The main reason we use version control is consistentency.
If the projects are not consistent then problems are going to occur and code is going to be lost.
Make sure you have buy in for the rest of the team. Maybe you can test your presentation on them? Hopefully, they see the need as well.
Nice to see good practices being initiated from the bottom up. Maybe everyone will be more likely to adopt the practice if it comes from one of their own instead of some management mandate.
To avoid things like
"Hey! What happens ? It worked yesterday."
The easiest way to convince management to invest Time in a SCCS is focus on backup and archival. By utilizing something like Subversion (SVN), you can restore any project to any point in time instantly. There is no need to have someone look through backup tapes or worry about tracking multiple versions in an obtuse directory structure.
There are obviously many other advantages (i.e. 2 people working on the same file at the same time), but backups are what quickly sold my company many years ago.
Others have mentioned the specific benefits of source control elsewhere, but I wanted to explicitly address the "VSS" portion of the question.
If your boss wants to use a Microsoft tool, Team Foundation Server with Team Suite is a very nice combination. It also has other tools included, such as bug tracking, documents, and reporting capabilities, which makes a nice platform on which to later improve your process. We are quite happy with it where I work, and my coworkers have told me horror stories about VSS.
Keep TFS in mind as a response to the 'Microsoft Tools' question.

version control practice

In my current job the supervisor's practice is to only check in production ready code. Most recently the project I was on involved work by 3 different developers with some file overlap. This meant manually integrating changes despite the fact that some changes took a day and then it was done. I wanted to see if this was a common practice and get suggestions on how to change this practice with the knowledge that many times my opinion means little in the grand scheme of things.
You can use various ways to handle this situation, depending on your source control system.
Private branches: Allow you to check in and work on code while you go, merging back and forth at appropriate times.
Shelvesets/pacakaged changesets: Allow you to store changesets and send them around for review - ensuring they're production ready before check in.
As to whether this is an appropriate way to work, we don't allow check-in to main branches without prior review. To pass review your code must pass various automated tools, and then must be acceptable to your peer reviewer. For some definitions of "production ready" - this is it. Therefore, we do something like what you do. However, we use private branches to ensure that check-ins can still be made while this is in progress, and that other check-ins don't have to interfere.
If production ready means tested in an integration environment, then it sounds like you may need staging branches or something similar.
Code that is checked in should be unit tested, but, to me, "production ready" implies that it's gone through integration and system testing. You can't do that until a code freeze, so I don't see how you can do that before every check in.
Start by switching away from VSS to something more reliable & feature-rich. See How to convince a company to switch their Source Control
Then apply known-good practices:
Check in often
Pick up others' changes often, to simplify merging
Use fast unit tests to make sure each change meets a minimum bar
Require that that the checked-in code always builds, and always passes tests.
Now you won't be "production ready" at this point: you will still need a couple weeks to test & fix before you can deploy. Getting that time down is awesome for you, and awesome for your customer, so invest in:
High quality automated acceptance tests.
wouldn't it be a good idea to have a testing branch of the repo that can have the non "production ready code" checked in after the changes are done and tested?
the main trunk should never have code checked in that breaks the build and doesn't pass unit tests, but branches don't have to have all those restrictions in place.
I would personally not approve of this because sometimes that's the best way to catch problem code with less experienced developers (by seeing it as they are working on it) and when you "check in early and often" you can rollback to earlier changes you made (as you were developing) if you decide that some changes you made earlier was actually a better idea.
I think it may be the version control we user, VSS in combination with a lack of time to learn the branching. I really like the idea of nightly check ins to help with development and avoid 'Going Dark'. I can see him being resistant to the trunks but perhaps building a development SS and when the code is production ready move it to production SS.
From the practices I have seen the term production quality is used as a 'frightener' to ensure that people are scared of breaking top of tree, not a bad thing to be honest because top of tree should always work if possible.
I would say that best practice is that you should only be merging distinct (i.e. seperate) functional components on the top of tree. If you have a significant overlap on deltas to the same source files I think this 'might' indicate that somewhere along the line the project management has broken down, and that those developers should have merged their changes to seperate integration branch before going in to the main line sources. An individual developer saying that they unit tested their stuff is irrelevant, because the thing they tested has changed!
Trying to solve integration problems on your main line codeline will inevitably stall other unrelated submissions.
Assuming that you are working in a centralized version control system (such as Subversion), and assuming that you have a concept of "the trunk" (where the latest well-working code lives):
If you work on new features in "features branches"/"experimental branches", then it's OK to commit code which is far from finished. (When the feature is done, you commit the well-behaving result into the "trunk".)
But you will not win a popularity contest if committing non-compiling/obviously non-working code into the "trunk" or a "release branch".
The Pragmatic Programmers have a book called Pragmatic Version Control using Subversion which includes a section with advice about branches.
Check in early and check in often for two main reasons -
1 - it might make it easier to integrate code
2 - in case your computer explodes your weeks of work isn't gone
An approach I particularly like is to have different life cycle versions in the depot. That is,for example, have a dev version of the code that is where the developers check in code that is in being worked on; then you could have a beta version, where you could add beta fixes to your code; and then a production version.
There is obvious overhead in this approach, such as the fact that you will have a larger workspace on you local machine, the fact that you will need need to have a migration process into place to move code from one stage to the next (which means a code freeze when doing the integration testing that goes with the migration), and that depending on the complexity of the project(s) you might need to have tools that change settings, environment variables, registry entries, etc.
All of this is a pain to set up, but you only do it once, and once you have it all in place, makes working on different stages of the code a breeze.
#bpapa
Nightly backups of work folders to servers will prevent losing more than a days work.
#tonyo
Let's see the requirement documents were completed the day after we finished coding. Does that tell you about our project management?
We are a small shop so while you would think change is easy there are some here that are unbending to the old ways.