Handling database files in projects - ruby-on-rails

Within my organisation we use a continuous integration system for deploying Ruby on Rails projects. The normal process for deploying a project is to set it up, enter the database credentials in config/database.yml and then run git update-index --assume-unchanged config/database.yml so local database settings won't be pushed to the server.
Recently switching between branches has been giving us error: Entry 'config/database.yml' not uptodate. Cannot merge. even when the -f / --force parameter is given branch changing will fail.
Does anyone have an idea why this isn't working or a better solution of handling it?

One solution is to add config/database.yml (And any other configuration files that differ between environments) to the .gitignore file.
You'll then need to remove the file from the git repository (Details Here) and manually create it on each environment.

Related

Capistrano 3 simple update

I have a Rails application which I deployed to a remote server with git and Capistrano 3. It works fine.
Sometimes after I change some files (in app/views, for example), I want to upload those changes to the current release without running the full cycle of deploy process.
I need one command to upload changed files (files in the last commit in git) to the current release directory on the remote server.
What is the best way to do it?
Improve Performance with Remote Cache
The way Capistrano works, it will create a new clone/export of your repository on every deploy. That can be slow, so there’s an option to add some extra commands to our deploy.rb recipe to speed things up. Add the following to the section of your deploy.rb where you describe your scm settings: set :deploy_via, :remote_cache
This command makes Capistrano do a single clone/checkout of your repository on your server the first time, then do an svn up or git pull on every deploy instead of doing an entire clone/export. If you deploy often, you’ll notice that this speeds up your deployments significantly.
Hope this help you what you are looking for!!!
For more detail check out this link. deploy-with-capistrano

How to set up a new workstation after adding .gitignore to the repo

I have a deployed rails website, and have a gitignore file in place. If I pull the app to a new computer or workstation, none of the gitignore files will be there since they are being igrnored. How do I correctly set up a new workstation? Do I just copy the files from another location and place them in the correct folders on the new workstation?
What some like to do, including myself, is to add example configuraton to the repo. For instance, you'd add database.yml to the gitignore so that nobody commits their personal passwords and then create a database.example.yml file that contains an example of how to set up database.yml
If those files you specified in the .gitignore are an essential part of your website configuration, they should be in the repository and not ignored.
You have several options:
Ignore files for everyone cloning the project
This is done using the file .gitignore in any folder of your git repository (people usually use one .gitignore at the root folder of the repository). The "ignore-behaviour" will be transmitted to everyone cloning or pulling the repository if you run git add .gitignore, commit and push.
Ignore files only for you, and only in this repository
This is done by using the same syntax as in the .gitignore, but in the file .git/info/exclude. The "ignore-behaviour" won't be transmitted to anyone, and only applies to you and to this specific repository.
Ignore files only for you, for all of your repositories
You can do this by defining a user .gitignore with
git config --global core.excludesfile ~/.gitignore.
Ignore files for all users on this computer, and for all of the repositories
You can do this with a system-wide .gitignore: sudo git config --system core.excludesfile /etc/gitignore
I personally intensively use 1 and 2 (the file .git/info/exclude can really be useful sometimes), but never the 3 and 4.

git repository move rails application code to live to test repositories

Hello I am having Two Branches on Github for the Rails Application.
One is Test and Other is Live.
Problem is Live branch is having the latest changes on it and Test is not having the lates changes.
so I want to transfer the code from Live to test on github.
Both the environment having different Database name and having different deploy.rb file with their environment.
So my concern is how to update the Test environment code with live environment code without changing the database and deploy.rb file.
Please Help me.
Thanks.
You could put a merge driver which would always keep your local version for those two files (deploy.rb and database.yml).
See as an example "How do I tell git to always select my local version for conflicted merges on a specific file?".
You can declare that merger driver in a .gitattributes file, which mean it will be published from upstream repo to upstream repo (as opposed to a git config solution which would be purely local to your repo)

Git + GitHub + Heroku

I am new to the world of Git, GitHub and Heroku. So far, I am enjoying this paradigm but coming from a background with SVN, things seems a bit complicated to me in the world of Git. I am facing a problem for which I am looking for a solution.
Scenario:
1. I have setup a new private project on GitHub. I forked the private project and now I have the following structure in my branch:
/project
/apps
/my-apps
/my-app-1
....
/my-app-2
....
/your-apps
/your-app-1
....
/your-app-2
....
/plugins
....
I can commit the code in my Fork on GitHub from my machine in any of the folders I want. Later on, these would be pulled into the master repository by the admin of the project.
2. For every individual application in the apps folder, I have setup an app on Heroku which is a Git Repo in itself where I push my changes when I am done with the user stories from my local machine. In short, every app in the apps folder is a Rails App hosted on Heroku.
Problem:
What I want is that when I push my changes into Heroku, they can be committed into my project fork on GitHub as well, so, it also has the latest code all the time.
The issue I see is that the code on Heroku is a Git Repo while the folders which I have on GitHub are part of a Repo.
So far, what I have researched is that there is something known as Submodule in the Git World which can come to the rescue, however, I have not been able to find some newbie instructions.
Can someone in the community be kind enough to share thoughts and help me to identify the solution of this problem?
The idea behind submodules is that they're all separate git repositories that you can include into a master one and rather instead of including all the files it includes a link to that submodule instead.
How to use submodules
To use a submodule, first you must extract out the directory and create it as its own git repository by using git init. Then you can upload this separately to Github or [place of your choosing] and to use it as a submodule use the command: git submodule add [place/to/put/it] git://github.com/you/proj1.
Separation is best
I would think it better to leave these separated out as their own git repositories and push to heroku from each one. The reason? It's more likely (I feel) that you're going to be working on one at a time and doing a git commit and git push heroku master for that one only.
If you wished however to deploy all applications at the same time you could recurse down the directory tree using this Ruby script placed in the top-level directory:
Dir["**/*"].select { |dir| File.directory?(dir) }.each do |f|
Dir.chdir(dir) do
`git push origin master`
`git push heroku master`
end
end
Of course this would only work if you have staged all your changes. I can't think of a way to automate that as Ruby <= 1.9 doesn't have the module to read your thoughts.

how do I deploy multiple branches to different directories via git push?

In production, I maintain two sites - beta and release. Each points to a different directory via a soft link (e.g.)
beta_public_html -> /home/scott/myapp/trunk/public
public_html -> /home/scott/myapp/branches/1.2.3/public
I'm a longtime svn user, moving to git. I'm used to deploying via svn update and changing the soft link on a new branch, things are pretty simple.
Now I'm moving to git. I still need to have the two soft links (it's a Rails app using Passenger), though now I want them to point to two different git branches ("beta" and "release", say). And I want to be able to update them via git push (or git pull).
Question Part 1: I'm not sure the best way to do this.
The way I had started to do it was to just deploy to two different remotes, e.g.
git push ssh://scott#x.com/home/scott/myapp-beta beta
git push ssh://scott#x.com/home/scott/myapp-release release
But this doesn't work because push doesn't update the working tree by default.
So I go into the remote directories and run git reset --hard the first time, and it pulls the working tree. But I push again and I can't get the new push to show up - it just stays at the initial one.
(BTW, note that I can't seem to push to "myapp-beta.git" - that fails, I have to push to the directory name. I am worried that this is part of the problem, but I don't know what I did wrong here.)
So, if the answer to Question 1 is that my method is fine, Question Part 2: what's wrong with what I'm actually doing? If there are hooks I should be using, can someone point me to them?
(An answer to Question 1 that says "run these seven manual steps" will not be a terribly useful answer, seeing as svn checkout + ln -s are two steps.)
Thanks. I want to get back to writing code.
The article Git push is worse than worsless has an interesting discussion about a similar issue.
One of its solution and conclusion involves:
a bare repository on the production server
a cloned repository with a hook to pull what has been pushed into the bare one
So in your case,
one bare repo on which you can push beta and release branches
two cloned repo 'beta' and 'release' with a hook to pull their respective branches from the bare repo.
In short: one step: git push. No more link to manage (since the directory no longer represent a branch in Git, unlike SVN)
Regarding the hook part, a post-receive hook in the bare repo could be all what you need
See Git Tip: Auto update working tree via post-receive hook
$ cd bare
$ chmod +x .git/hooks/post-receive
with a post-receive hook like
#!/bin/sh
cd ../../beta
env -i git reset --hard
cd ../../release
env -i git reset --hard
Note:
the post-receive hook starts out with the GIT_DIR environment variable set to the repo/.git folder, so no matter what path you 'cd' into it will always try to run any following git commands there.
Fixing this is simply a matter of unsetting the GIT_DIR.
'env -i' does just that: it ignores the inherited environment completely and uses only the supplied variables and values.
The solution is to push to single repository, which would employ update or post-receive hook.
There are a few separate possibilities to create two checkouts, which can be used in hook (on server). Going from most lightweight:
If you don't need for those two checked out directories (checked out versions) to actually be git repositories, you can simply use git-archive to export two snapshots (two branches)
git archive --format=tar --prefix=public_html/ master | (cd /var/www/html && tar xf -)
git archive --format=tar --prefix=beta_public_html/ devel | (cd /var/www/html && tar xf -)
where 'master' and 'devel' are names of branches that you wanted to have checked out. Note that --format=tar is not strictly speaking needed, as tar format is default for "git archive". You might also want to remove old contents ("rm -rf public_html/" before "tar xf -" in first line, joined with "&&", and similarly for the second line).
Alternate way of exporting files would be to use low-level commands "git read-tree" (which writes tree to index) and "git checkout-index" (which copies files from index to working area).
In this solution the repository you push into can (and should) be bare, i.e. without working directory itself.
Another solution would be for the repository you push into to have two working directories, which can be created using git-new-workdir script from contrib/workdir. Each of those working areas would have be a checkout of appropriate branch of this repository.
Then update or post-receive hook would unset GIT_DIR, go to those working areas (public_html and beta_public_html), and do "git reset --hard" there.
In this solution "checkouts" would have some git-related metainfo in them (in hidden .git directory).
Yet another solution would be to have two (additional) slave repositories. Pushing into main (master) repository would then (via hook) either push into those two slave repositories, where their hooks would do "git reset --hard" or equivalent, or go to those two slave repositories and do a "git pull" from master there.
Those two slave repositories would be non-bare, and can be [directly in] public_html and beta_public_html. In this solution "checkouts" would be full-fledged git repositories itself.
You can improve this setup by having those slave repositories to have "alternates" (alternate object database) to point to master repository (i.e. be cloned with "git clone --shared ..."); without this object database in slaves starts hardlinked to master. This of course is possible only if master and slaves are on the same filesystem.
Note this solution allows for master repository to be on different host than slave repositories. (although I guess this is flexibility you don't need).
Finally you can instead of current setup deploy gitweb or some other git web interface (see InterfacesFrontendsAndTools and Gitweb wiki pages for a partial list), so that your users can browse different versions and different branches of your repository at their leisure.
In gitweb (and I guess also in other git web interface) thanks to path_info URL support you can view files in browser, and follow links correctly (if they are local), see e.g. git.html from 'html' branch of git.git repository at repo.or.cz.
P.S. "git push" does not update working directory in remote repository by default, because if somebody is working in the non-bare repository you push into, such sideways push can be very unexpected and lead to loss of work.
I use a post-receive hook like this to publish my website, because Git does not touch the working directory when doing a push. The remote repository is a non-bare repository, i.e. it has a working directory.
if [ -n $GIT_DIR ]; then
# Current dir is "<reporoot>/.git/", but we need to run reset at "<reporoot>/".
# Clearing GIT_DIR is needed, or reset will fail with "fatal: Not a git repository: '.'"
unset GIT_DIR
cd ..
fi
git reset --hard
(BTW, note that I can't seem to push to "myapp-beta.git" - that fails, I have to push to the directory name. I am worried that this is part of the problem, but I don't know what I did wrong here.)
When creating a bare Git repository (git init --bare) which does not have a working directory, it is a convention to name the directory "something.git". When having a non-bare repository, the repository is actually in the ".git" subdirectory, so the full path is "something/.git". It seems that in either case you can leave out the ".git" part and Git will detect it automatically.
I'm not really opposed to the other solutions, but I think there's a less hack'ish "Git way" to do this. Here's what I would do:
On my server, I'd set up a sort of a centralized repository (to be managed by Gitosis or some such thing).
From the client end, I'd constantly pull from the repository, make changes and push back. Branches are ofcourse, managed automatically.
I'd pull the required branch from Gitosis into public_html/ beta_public_html of the server. I'd keep it in sync with Gitosis periodically using a Cron job. If you don't like the Cron job idea, you could always use some sort of a hook + script as the others have pointed out.

Resources