Best practices for version information? - language-agnostic

I am currently working on automating/improving the release process for packaging my shop's entire product. Currently the product is a combination of:
Java server-side codebase
XML configuration and application files
Shell and batch scripts for administrators
Statically served HTML pages
and some other stuff, but that's most of it
All or most of which have various versioning information contained in them, used for varying purposes. Part of the release packaging process involves doing a lot of finding, grep'ing and sed'ing (in scripts) to update the information. This glue that packages the product seems to have been cobbled together in an organic, just-in-time manner, and is pretty horrible to maintain. For example, some Java methods create Date objects for the time of release, the arguments for which are updated by a textual replacement, without compiler validation... just, urgh.
I'm trying avoid giving examples of actual software used (i.e. CVS, SVN, ant, etc.) because I'd like to avoid the "use xyz's feature to do this" and concentrate more on general practices. I'd like to blame shoddy design for the problem, but if I had to start again, still using varying technologies, I'd be unsure how best to go about handling this, beyond laying down conventions.
My questions is, are there any best practices or hints and tips for maintaining and updating versioning information across different technologies, filetypes, platforms and version control systems?

Create a properties file that contains the version number and have all of the different components reference the properties file
Java files can reference the properties through
XML can use includes?
HTML can use a JavaScript to write the version number from the properties in the HTML
Shell scripts can read in the file

Indeed, to complete Craig Angus's answer, the rule of thumb here should be to not include any meta-informations in your normal delivery files, but to report those meta-data (version number, release date, and so on) into one special file -- included in the release --.
That helps when you use one VCS (Version Control System) tool from the development to homologation to pre-production.
That means whenever you load a workspace (either for developing, or for testing or for preparing a release into production), it is the versionning tool which gives you all the details.
When you prepare a delivery (a set of packaged files), you should ask that VCS tool about every meta-information you want to keep, and write them in a special file itself included into the said set of files.
That delivery should be packaged in an external directory (outside any workspace) and:
copied to a shared directory (or a maven repository) if it is a non-official release (but just a quick packaging for helping the team next door who is waiting for your delivery). That way you can make 10 or 20 delivers a day, it does not matter: they are easily disposable.
imported into the VCS in order to serve as official deliveries, and in order to be deployed easily since all you need is to ask the versionning tool for the right version of the right deliver, and you can begin to deploy it.
Note: I just described a release management process mostly used for many inter-dependant projects. For one small single project, you can skip the import in the VCS tool and store your deliveries elsewhere.

In addition to Craig Angus' ones include the version of tools used.

Related

What is "vendoring"?

What is "vendoring" exactly? How would you define this term?
Does it mean the same thing in different programming languages? Conceptually speaking, not looking at the exact implementation.
Based on this answer
Defined here for Go as:
Vendoring is the act of making your own copy of the 3rd party packages
your project is using. Those copies are traditionally placed inside
each project and then saved in the project repository.
The context of this answer is in the Go language, but the concept still applies.
If your app depends on certain third-party code to be available you could declare a dependency and let your build system install the dependency for you.
If however the source of the third-party code is not very stable you could "vendor" that code. You take the third-party code and add it to your application in a more or less isolated way. If you take this isolation seriously you should "release" this code internally to your organization/working environment.
Another reason for vendoring is if you want to use certain third-party code but you want to change it a little bit (a fork in other words). You can copy the code, change it, release it internally and then let your build system install this piece of code.
Vendoring means putting a dependency into you project folder (vs. depending on it globally) AND committing it to the repo.
For example, running cp /usr/local/bin/node ~/yourproject/vendor/node & committing it to the repo would "vendor" the Node.js binary – all devs on the project would use this exact version. This is not commonly done for node itself but e.g. Yarn 2 ("Berry") is used like this (and only like this; they don't even install the binary globally).
The committing act is important. As an example, node_modules are already installed in your project but only committing them makes them "vendored". Almost nobody does that for node_modules but e.g. PnP + Zero Installs of Yarn 2 are actually built around vendoring – you commit .yarn/cache with many ZIP files into the repo.
"Vendoring" inherently brings tradeoffs between repo size (longer clone times, more data transferred, local storage requirements etc.) and reliability / reproducibility of installs.
Summarizing other, (too?) long answers:
Vendoring is hard-coding the often forked version of a dependency.
This typically involves static linking or some other copy but it doesn't have to.
Right or wrong, the term "hard-coding" has an old and bad reputation. So you won't find it near projects openly vendoring, however I can't think of a more accurate term.
As far as I know the term comes from Ruby on Rails.
It describes a convention to keep a snapshot of the full set of dependencies in source control, in directories that contain package name and version number.
The earliest occurrence of vendor as a verb I found is the vendor everything post on err the blog (2007, a bit before the author co-founded GitHub). That post explains the motivation and how to add dependencies. As far as I understand the code and commands, there was no special tool support for calling the directory vendor at that time (patches and code snippets were floating around).
The err blog post links to earlier ones with the same convention, like this fairly minimal way to add vendor subdirectories to the Rails import path (2006).
Earlier articles referenced from the err blog, like this one (2005), seemed to use the lib directory, which didn't make the distinction between own code and untouched snapshots of dependencies.
The goal of vendoring is more reproducibility, better deployment, the kind of things people currently use containers for; as well as better transparency through source control.
Other languages seem to have picked up the concept as is; one related concept is lockfiles, which define the same set of dependencies in a more compact form, involving hashes and remote package repositories. Lockfiles can be used to recreate the vendor directory and detect any alterations. The lockfile concept may have come from the Ruby gems community, but don't quote me on that.
The solution we’ve come up with is to throw every Ruby dependency in vendor. Everything. Savvy? Everyone is always on the same page: we don’t have to worry about who has what version of which gem. (we know) We don’t have to worry about getting everyone to update a gem. (we just do it once) We don’t have to worry about breaking the build with our libraries. […]
The goal here is simple: always get everyone, especially your production environment, on the same page. You don’t want to guess at which gems everyone does and does not have. Right.
There’s another point lurking subtlety in the background: once all your gems are under version control, you can (probably) get your app up and running at any point of its existence without fuss. You can also see, quite easily, which versions of what gems you were using when. A real history.

What should NOT be under source control?

It would be nice to have a more or less complete list over what files and/or directories that shouldn't (in most cases) be under source control. What do you think should be excluded?
Suggestion so far:
In general
Config files with sensitive information (passwords, private keys etc.)
Thumbs.db, .DS_Store and desktop.ini
Editor backups: *~ (emacs)
Generated files (for instance DoxyGen output)
C#
bin\*
obj\*
*.exe
Visual Studio
*.suo
*.ncb
*.user
*.aps
*.cachefile
*.backup
_UpgradeReport_Files
Java
*.class
Eclipse
I don't know, and this is what I'm looking for right now :-)
Python
*.pyc
Temporary files
- .*.sw?
- *~
Anything that is generated. Binary, bytecode, code/documents generated from XML.
From my commenters, exclude:
Anything generated by the build, including code documentations (doxygen, javadoc, pydoc, etc.)
But include:
3rd party libraries that you don't have the source for OR don't build.
FWIW, at my work for a very large project, we have the following under ClearCase:
All original code
Qt source AND built debug/release
(Terribly outdated) specs
We do not have built modules for our software. A complete binary is distributed every couple weeks with the latest updates.
OS specific files, generated by their file browsers such as
Thumbs.db and .DS_Store
Some other Visual Studio typical files/folders are
*.cachefile
*.backup
_UpgradeReport_Files
My tortoise global ignore pattern for example looks like this
bin obj *.suo *.user *.cachefile *.backup _UpgradeReport_Files
files that get built should not be checked in
I would approach the problem a different way; what things should be included in source control? You should only source control those files that:
( need revision history OR are created outside of your build but are part of the build, install, or media ) AND
can't be generated by the build process you control AND
are common to all users that build the product (no user config)
The list includes things like:
source files
make, project, and solution files
other build tool configuration files (not user related)
3rd party libraries
pre-built files that go on the media like PDFs & documents
documentation
images, videos, sounds
description files like WSDL, XSL
Sometimes a build output can be a build input. For example, an obfuscation rename file may be an output and an input to keep the same renaming scheme. In this case, use the checked-in file as the build input and put the output in a different file. After the build, check out the input file and copy the output file into it and check it in.
The problem with using an exclusion list is that you will never know all the right exclusions and might end up source controlling something that shouldn't be source controlled.
Like Corey D has said anything that is generated, specifically anything that is generated by the build process and development environment are good candidates. For instance:
Binaries and installers
Bytecode and archives
Documents generated from XML and code
Code generated by templates and code generators
IDE settings files
Backup files generated by your IDE or editor
Some exceptions to the above could be:
Images and video
Third party libraries
Team specific IDE settings files
Take third party libraries, if you need to ship or your build depends on a third party library it wouldn't be unreasonable to put it under source control, especially if you don't have the source. Also consider some source control systems aren't very efficient at storing binary blobs and you probably will not be able to take advantage of the systems diff tools for those files.
Paul also makes a great comment about generated files and you should check out his answer:
Basically, if you can't reasonably
expect a developer to have the exact
version of the exact tool they need,
there is a case for putting the
generated files in version control.
With all that being said ultimately you'll need to consider what you put under source control on a case by case basis. Defining a hard list of what and what not to put under it will only work for some and only probably for so long. And of course the more files you add to source control the longer it will take to update your working copy.
Anything that can be generated by the IDE, build process or binary executable process.
An exception:
4 or 5 different answers have said that generated files should not go under source control. Thats not quite true.
Files generated by specialist tools may belong in source control, especially if particular versions of those tools are necessary.
Examples:
parsers generated by bison/yacc/antlr,
autotools files such as configure or Makefile.in, created by autoconf, automake, libtool etc,
translation or localization files,
files may be generated by expensive tools, and it might be cheaper to only install them on a few machines.
Basically, if you can't reasonably expect a developer to have the exact version of the exact tool they need, there is a case for putting the generated files in version control.
This exception is discussed by the svn guys in their best practices talk.
Temp files from editors.
.*.sw?
*~
etc.
desktop.ini is another windows file I've seen sneak in.
Config files that contain passwords or any other sensitive information.
Actual config files such a web.config in asp.net because people can have different settings. Usually the way I handle this is by having a web.config.template that is on SVN. People get it, make the changes they want and rename it as web.config.
Aside from this and what you said, be careful of sensitive files containing passwords (for instance).
Avoid all the annoying files generated by Windows (thumb) or Mac OS (.ds_store)
*.bak produced by WinMerge.
additionally:
Visual Studio
*.ncb
The best way I've found to think about it is as follows:
Pretend you've got a brand-new, store-bought computer. You install the OS and updates; you install all your development tools including the source control client; you create an empty directory to be the root of your local sources; you do a "get latest" or whatever your source control system calls it to fetch out clean copies of the release you want to build; you then run the build (fetched from source control), and everything builds.
This thought process tells you why certain files have to be in source control: all of those necessary for the build to work on a clean system. This includes .designer.cs files, the outputs of T4 templates, and any other artifact that the build will not create.
Temp files, config for anything other than global development and sensitive information
Things that don't go into source control come in 3 classes
Things totally unrelated to the project (obviously)
Things that can be found on installation media, and are never changed (eg: 3rd-party APIs).
Things that can be mechanically generated, via your build process, from things that are in source control (or from things in class 2).
Whatever the language :
cache files
generally, imported files should not either (like images uploaded by users, on a web application)
temporary files ; even the ones generated by your OS (like thumbs.db under windows) or IDE
config files with passwords ? Depends on who has access to the repository
And for those who don't know about it : svn:ignore is great!
If you have a runtime environment for your code (e.g. dependency libraries, specific compiler versions etc.) do not put the packages into the source control. My approach is brutal, but effective. I commit a makefile, whose role is to downloads (via wget) the stuff, unpack it, and build my runtime environment.
I have a particular .c file that does not go in source control.
The rule is nothing in source control that is generated during the build process.
The only known exception is if a tool requires an older version of itself to build (bootstrap problem). In that case you will need a known good bootstrap copy in source control so you can build from blank.
Going out on a limb here, but I believe that if you use task lists in Visual Studio, they are kept in the .suo file. This may not be a reason to keep them in source control, but it is a reason to keep a backup somewhere, just in case...
A lot of time has passed since this question was asked, and I think a lot of the answers, while relevant, don't have hard details on .gitignore on a per language or IDE level.
Github came out with a very useful, community collaborated list of .gitignore files for all sorts of projects and IDEs that is worth taking a look.
Here's a link to that git repo: https://github.com/github/gitignore
To answer the question, here are the related examples for:
C# -> see Visual Studio
Visual Studio
Java
Eclipse
Python
There are also OS-specific .gitignore files. Following:
Windows
OS X
Linux
So, assuming you're running Windows and using Eclipse, you can just concatenate Eclipse.gitignore and Windows.gitignore to a .gitignore file in the top level directory of your project. Very nifty stuff.
Don't forget to add the .gitignore to your repo and commit it!
Chances are, your IDE already handles this for you. Visual Studio does anyway.
And for the .gitignore files, If you see any files or patterns missing in a particular .gitignore, you can open a PR on that file with the proposed change. Take a look at the commit and pull request trackers for ideas.
I am always using www.gitignore.io to generate a proper one .ignore file.
Opinion: everything can be in source control, if you need to, unless it brings significant repository overhead such as frequently changing or large blobs.
3rd party binaries, hard-to-generate (in terms of time) generated files to speed up your deployment process, all are ok.
The main purpose of source control is to match one coherent system state to a revision number. If it would be possible, I'd freeze the entire universe with the code - build tools and the target operating system.

Mercurial: How to manage common/shared code

I'm using Mercurial for personal use and am conteplating it for some distributed projects as an alternative to SVN for various reasons.
I'm getting comfortable with using it for self contained projects and can see various options for sharing however I haven't yet found any guidance on managing common libraries to be included in multiple projects in a similar manner to that provided by externals in subversion.
The most obvious shared lump of code is error handling and reporting - we want this to be pretty much the same in all projects (its fairly well evolved). There is also utility code, control libraries and similar that we find better to have as projects built with each solution than to pull in as compiled classes (not least because it ensures they are kept up to date, continuous integration helps us address breaking changes).
Thoughts (I hate open ended questions, but I want to know what, if anything, others are doing).
Mercurial 1.3 now includes nested repository support, which can be used to express dependencies. The other option is to let your build system handle the download and tracking of dependencies using something like ivy or maven though those are more focused on pulling down compiled code.
The world has changed since I asked that question and the solution I now use is different.
The simple answer is now to use packages (specifically NuGet as I do .NET) to deliver the common code instead of nesting repos and including the projects in a solution.
So I have common code built into NuGet packages by and hosted using TeamCity and where previously I would have an external and include the project/source I would now just reference the package.
Use the Forest Extension it emulates svn externals for HG, to some extent that is.
Subrepository (with good guide) or Guestrepo "to overcome ... limitations" (of subrepos) is today's language-agnostic answer

How to display credits

I want to give credit to all open source libraries we use in our (commercial) application. I thought of showing a HTML page in our about dialog. Our build process uses ant and the third party libs are committed in svn.
What do you think is the best way of generating the HTML-Page?
Hard code the HTML-Page?
Switch dependency-management to apache-ivy and write some ant task to generate the html
Use maven-ant-tasks and write some ant task to generate the HTML
Use maven only to handle the dependencies and the HTML once, download them and commit them. The rest is done by the unchanged ant-scripts
Switch to maven2 (Hey boss, I want to switch to maven, in 1 month the build maybe work again...)
...
What elements should the about-dialog show?
Library name
Version
License
Author
Homepage
Changes made with link to source archive
...
Is there some best-practise-advice? Some good examples (applications having a nice about-dialog showing the dependencies)?
There are two different things you need to consider.
First, you may need to identify the licenses of the third-party code. This is often down with a THIRDPARTYLICENSE file. Sun Microsystems does this a lot. Look in the install directory for OpenOffice.org, for example. There are examples of .txt and .html versions of such files around.
Secondly, you may want to identify your dependencies in the About box in a brief way (and also refer to the file of license information). I would make sure the versions appear in the About box. One thing people want to quickly check for is an indication of whether the copy of your code they have needs to be replaced or updated because one of your library dependencies has a recently-disclosed bug or security vulnerability.
So I guess the other thing you want to include in the about box is a way for people to find your support site and any notices of importance to users of the particular version (whether or not you have a provision in your app for checking on-line for updates).
Ant task seems to be the best way. We do a similar thing in one of our projects. All the open source libraries are present in a specified folder. An Ant task reads the manifest of these libraries, versions and so on and generates an HTML, copies into another specified folder from where it is picked up by the web container.
Generating the page with each build would be wasteful if the libraries are not going to change often. Library versions may change, but the actual libraries don't. Easier to just create a HTML page would be the easiest way out, but that's one more maintenance head ache. Generate it once and include it with the package. The script can always be run again in case some changes are being made to the libraries (updating versions, adding new libraries).

How to automate the tasks for releasing open-source-software?

Everyone managing open-source-software runs into the problem, that with the time the process of releasing a new version gets more and more work. You have to tag the release in your version-control, create the distributions (that should be easy with automated builds), upload them to your website and/or open-source-hoster. You have to announce the new release with nearly the same message on chosen web-forums, the news-system on sourceforge, mailinglists and your blog or website. And you have to update the entry of your software on freshmeat. Possible more tasks have to be done for the release.
Do you developed techniques to automate some of these tasks? Does software exist that supports you with this?
Pragmatic Project Automation shows how to do all of that. They use Ant for practically everything in the book, so if you know Ant you can make different targets to do any step in the build-release cycle.
For my Perl stuff, I wrote Module::Release. In the top-level directory I type a single command:
% release
If checks several things and dies if anything is wrong. If everything checks out, it uploads the distribution.
It automates my entire process:
Test against multiple versions of Perl
Test distribution files
Check the status of source control
Check for code and distribution quality metrics
Update changes file
Determine new version number
Release code to multiple places
Tag source control with new version number
Everyone seems to write their own release automator though. Most people like their process how they like their process, so general solutions don't work out that well socially.
Brad Fitzpatrick has ShipIt which is a Perl program to automate releases. There's slightly more info in his original announcement.