Mercurial project overlapping? - mercurial

I have a site/backoffice solution that works with this structure:
/bo // mercurial repo
/site // site files
/www/admin // mercurial repo
/var // site specific vars
The backoffice works seamless across several sites and therefore all projects have a mercurial repo and code contributions done to project A always get replicated on projects B and C. This has worked well so far but now I feel I should also be doing a repo to the root /.
Is it possible? Can I have a repo on / excluding both the /bo and the /www/admin and have it all work nicely together or should I anticipate problems?

You could setup a repo at the root, and:
declare /site and /var as SubRepos,
while ignoring /bo and /www/admin
That way, all your current repos still go on unchanged, but you also have one global repo with only what you need.

Related

How to properly use hg share extension?

Say I have cloned a repo to a directory called ~/trunk and I want to share a branch named my-new-branch to the directory ~/my-new-branch. How would I do that with the hg share extension?
This is what I've been doing:
cd ~
hg share trunk my-new-branch
But then when I cd into the new directory I have to hg up to the branch?
Confused.
IMO share is a very useful command which has some great advantages over clone in some cases. But I think it is unfortunately overlooked in many instances.
What share does is to re-use the 'store' of Mercurial version control information between more than one local repository. (It has nothing directly to do with branching.)
The 'store' is a bunch of files which represents all the history Mercurial saves for you. You don't interact with it directly. Its a black box 99.99% of the time.
share differs from the more commonly-used clone command in that clone would copy the information store, taking longer to run and using potentially a lot more disk space.
The "side effect" of using share rather than clone is that you will instantly see all the same commits in every shared repository. It is as if push/pull were to happen automatically among all the shared repos. This would not be true with clone, you'd have to explicitly push/pull first. This is quite useful but something to be mindful of in your workflow because it may surprise you the first time you use it if you are only used to clone.
If you want to work in multiple branches (named or unnamed) of your project simultaneously,
either clone or share will work fine. One you have created the second repository, yes you need to update it to whatever changeset you want to begin working on.
Concrete example using share:
hg clone path\to\source\repo working1 # Create local repo working1 cloned from somewhere
cd working1
hg up branchname1
cd ..
hg share working1 working2 # shares the 'store' already used for working1 with working2
cd working2
hg up branchname2 # some other branch or point to start working from
As soon as you commit something in working1 that commit will be visible in the history of working2. But since they are not on the same branch this has no real immediate effect on working2.
working2 will retain path\to\source\repo as its default push/pull location, just like working1.
My own practice has been to create numerous locally shared repositories (quick, easy, saves space) and work in various branches. Often I'll even have a few of them on the same named branch but set to different points in history, for various reasons. I no longer find much need to actually clone locally (on the same PC).
A caveat -- I would avoid using share across a network connection - like to a repo on a mapped network drive. I think that could suffer some performance or even reliability issues. In fact, I wouldn't work off a network drive with a Mercurial repo (if avoidable) in any circumstance. Cloning locally would be safer.
Secondly -- I would read the docs, there are a few weird scenarios you might encounter; but I think these are not likely just based on my own experience.
Final note: although share is implemented as an "extension" to Mercurial, it has been effectively a part of it since forever. So there is nothing new or experimental about it, don't let the "extension" deal put you off.

Can I work in the repository in a single user Mercurial workflow?

I use Mercurial in a single-user workflow to have the option to roll back changes if my coding or writing goes horribly wrong (I primarily use the Stata and R statistics packages and LaTeX). While working only locally, this has been easy since all I have is the main repo.
Recently I have started ssh-ing into a Linux server for more computational power. So far I have been manually copying files back and forth and using Mercurial only locally, but I would like to use Mercurial to take care of this and keep these two workflows synchronized. Also, I like the ability to code both locally (on my laptop or desktop) and on the server.
Do I need to work on a clone of the main repo on the server and keep the main repo untouched? Or can I work directly in the main repo when I am on the server? In this question #gizmo points to this workflow guide; the "single developer" discussion is helpful, but it's still not clear to me that I can work in the main repo while I'm on the server without causing some major problem that I don't yet understand.
Thanks!
Edit: I should add that I have worked through Joel Spolsky's HgInit.com tutorial and I'm comfortable pushing/pulling/cloning/etc over ssh, but I am still not sure if I can work in the main repo without causing heartache later. Or maybe this is more a philosophical question? Thanks!
Mercurial is DVCS, it means - in each location you have both: local working copy and local repository
Mercurial is DVCS, it means - you can freely exchange (pull|push) data between repos (if they provide remote-access methods).
If you
comfortable pushing/pulling/cloning/etc over ssh
and don't forget perform pull|push cycle around your work at home (in order to don't run hg serve at home-host and sync from server as source) you don't get any headache at all with perfect linear aggregated history on each place. And even you forget to sync repo sometimes, you get in worst case two heads later, which you'll be able to merge easy (doesn't know formats of Stata and R data-files, but LaTeX, as text, is mergeable)
There is no problem with working directly in the repository on your server. From Mercurial's point of view, the "main" repository is just another random repository — Mercurial doesn't consider it to be special.
You don't say this directly, but one thing that people ask is "What happens when I push to the server?" The answer is that hg push only sends data into the repository (the .hg/ folder). The working copy is not touched on the server when you push to it. Since you push new changesets to the server, you might need to run hg update the next time you work on the server. This is just like if you had run hg pull on the server — there you'll also merge or update afterwards.
I have this situation all the time: I create a repository at home and clone it to my computer at work. I change files in either location and push/pull between the two repositories. If I need to share my work with others, then I make a repository at Bitbucket and push the code there. That way Bitbucket serves as a nice canonical repository for the code and I typically change the default path to Bitbucket in the repositories at home and at work. So at home I would have:
[paths]
default = httsp://bitbucket.org/mg/<repo>/
work = ssh://mg#work/<repo>
so that I can do hg push to send things to Bitbucket and hg pull work to grab things directly from work (in case I forgot to push to Bitbucket before leaving).

GIt Workflow dev and production - where should I create the repos?

I've read somewhere* a setup like this would be nice:
Two main branches, one for each server.
Pushing to master sends changes on to live;
Pushing to dev/stage (or whatever you call it) sends changes to staging;
Workflow:
Create branch from dev;
work locally until you're ready to test;
merge back to dev;
push to Hub, which sends changes to dev/staging server.
Once you're ready with those to go live:
merge from dev to master,
then push master to Hub, which sends those changes on to the live server.
Two main branches, one for each server.
So I have one branch "production" on "webroot/myliveapp/"
and another branch "development" on "webroot/devapp/"
Where should the repository be ?
UPDATE:
I mean:
We will have, according to this flow:
Prime repo;
Bare repo hub;
Clones;
The development and production branches should belong to one repository, right ?
If this is correct, then were should we issue the FIRST git init command ?
On our Prime repo ?
So we will have:
"webroot/myliveapp/" - production branch;
"webroot/devapp/" - development branch;
"webroot/.git" - Prime repository;
Does this make sense ?
Or should the Prime repository correspond to our production branch location ?
*Note: if you need a context about what workflow I'm trying to implement, is this one:
http://joemaller.com/990/a-web-focused-git-workflow/
Thanks for the update on your question, it is more clear now.
I believe the problem you're having is based on a misunderstanding of Git workflow; Git doesn't equate directories to branches, it equates a view of your filesystem to branches. This is powerful - but easy to shoot yourself in the foot. Let me explain.
Git acts more like a database-backed, differentially-versioned, history tracking filesystem in itself. It is "above" your filesystem, not "part of" it. It doesn't use your filesystem to represent branches, rather, when you check out a different branch, all the files in your filesystem will change to be the files in that branch. You are asking Git to make your filesystem represent the alternate reality of that branch.
If you are on branch master, and it has a file root/foo.txt committed, and you check out branch experiment, which does not have root/foo.txt committed, you will find that file gone when you look for it. It is a part of master, not experiment, and so it is not present in your filesystem. This is why Git is really picky about your current branch being committed before it lets you switch branches - if you have unstaged changes on your filesystem that Git doesn't know about, it refuses to blow them away by overwriting them with a different reality. You have to intervene to make things right first.
So, to answer the quesiton, don't create subdirectories for "myliveapp" and "devapp" - create different branches. Just have your one codebase under "webroot". Then, hack away on, say, the "unstable" branch, committing your changes as usual. You can then switch all of the files in your repository to be at the version of your dev server's files by switching to the "devapp" branch, and you can similarly switch back to "unstable" at any time.
When you want to update a branch, e.g. doing an update of your dev server, you can merge "unstable" into "devapp". This will make all of the files of "devapp" look like those of "unstable", bringing it up to date.
One other thing to note: the difference between a prime repo, a bare repo, and clones is almost nil. There is virtually no difference in the software; rather, it's a human convention to say "Linus' kernel is the canonical Linux kernel". With that understanding:
A prime repo is just one repository that everyone agrees holds the "canonical" version of the software. That is, whenever a developer has made a change they want everyone to see, rather than saying, "Pull my version of devapp", they can say, "I've published my changes to our prime repo." It's simply an easy convention for people to rally around.
A clone is a copy of some other repo. I could clone the prime repo, make changes, and then you can clone my repo. If you make changes, you can push them either onto the prime repo or onto mine, as long as the merge is valid and you have permissions on the computer.
A bare repo simply has no "working copy" - there is no "webroot" directory on that computer. It's empty with only the .git directory - which is fine for servers where nobody needs to alter the files.
Finally, the .git dir doesn't hold the files of your repo, it holds the git configuration and database. It's your entire repository history in database form, which is used to populate the rest of the repo with a particular version of your software. That's why I made the comment: you can locally check out any version of any alternate reality of the repository, with no network communication, at any time - because it's all there in the .git dir. The only network communication necessary is for when you want to sync your local repository to some other repository, using push or pull.

Mercurial repo inside a repo

Is it possible to create a mercurial repository inside an existing mercurial repository?
The idea is to handle subdirectories of a repository as different repositories, how do you do that?
I'm not talking about subrepos (at least, if I understood the purpose of subrepos...), but if this is how subrepos do exist for, I got it wrong and I'll try to get it right :)
Thanks
~Aki
EDIT: To be more clear, I'd like to know what happens, the practices and the implications of having a repository inside another one, without specifying modules/subrepos.
In other words: what happens if I just do:
hg init globalRepo
hg init globalRepo/subRepo
and use these two repositories as-are?
It works well. Long before the subrepo support was added in Mercurial 1.3, lots of folks kept their entire home directories in a mercurial repo for tracking their .bashrc files and the like. Then within their home dir they'd have many clones of other repos.
Whenever you invoke mercurial (without the -R option) it looks in the current directory for a .hg directory and then just keeps going up directories until it finds one. So if you're in a repo that is in a repo, your commands will always act on the innermost repo you're in.
The caveat is that you want to make sure not to have files added to the outer repo that end up inside the inner repo. Then you'll have two repos updating the same files.
As you can see in this SO question, you can make that kind of nested hg init, even though it is usually reserved for defining subRepo (which is not what you are after).
Normally it should work as two independant repos, but I would advise adding an hgignore rule in the globalRepo in order to ignore the subRepo content altogether.
Here are some docs on nested repositories.

Can one Mercurial repository live inside another Mercurial repository?

Can one hg repo live inside another hg repo on my local file system?
I am pulling down the bitbucket wiki for 'sandbox', and I want to know if this should be placed in repos/sandbox/wiki or repos/sandbox-wiki.
Is the former okay to do?
Edit: See Subrepository.
The short answer is yes, but I can't imagine why you would want to.
In your example, I think you should go with:
repos/sandbox-wiki
[edit] Additionaly:
Yo Dowg, I herd you like repositories.
So we put a repo in your repo so you can version while you version
:-)
Yes and no. Depends on what you want to do. You can create repo 'sandbox/wiki' but files in this inner repos won't be commited in the outer 'sandbox' repo (#Jason is right). If you don't want to, no problem.
Try explicitly adding files from wiki repos in sandox and you'll get the message below. If you just add path to some directory containing an inner repo the files will just be ignored.
From sandox root directoy:
hg add wiki/myfile
abort: path 'wiki/myfile' is inside repo 'wiki'
Mercurial does not allow nested repositories, but there is at least one reason for them:
Imagine that you are working in a project: /MyProject. In this folder you put everything: code, documentation, tests, etc.
You want to backup your work because it is very important, so you create a repository for /MyProject. Then, overtime you use bundles to save the evolution of /MyProject and back up them in a USB flash memory so that you can recover everything just in case your hard drive breaks.
Remember that /MyProject contains everything. And among all those things, there are the main code and some auxiliary projects. You also want to track the progress of an auxiliary project that is in /MyProject/AuxiliaryProject, so you use Mercurial to track its evolution.
Also, you want to have a separate repository for the main code: /MyProject/Main
In this situation you want nested repositories: one big one for being able to back-up everything using bundles and child repositories for managing each subproject.
I think Mercurial should give the user several options when initializing a repository. For example:
- ignore nested repositories
- include nested repositories but ignoring .Hg folders (i.e. act as if there were no nested repositories but do not ignore the information contained in the nested respositories).
- include nested repositories and also include .Hg folders (makes sense for back-up purposes)
--------- Edit:
Subrepositories is a feature that is work in progress:
https://www.mercurial-scm.org/wiki/subrepos
Also, there is an extension named "forest" that might become obsolete in the future:
https://www.mercurial-scm.org/ForestExtension
You'd need to set up an .hgignore file in sandbox to exclude wiki because mercurial assumes that it is responsible for all descendants. This would probably generate more user confusion than it is worth.