For our project, we have two repositories: Main and Automated Testing. In the Testing repository, we allow multiple heads, so one commonly used "hg push -f" when pushing to the Testing repository. But using "push -f" is a bad habit, as one may accidentally use this for other repositories, too.
So I am looking for some configuration option, preferably on the repository side, which allows pushing multiple heads without using -f -- does Mercurial provide such an option?
(I know that I can install a hook to an repository to prevent it being the target of a forced push, but I would like to get rid of the need to use -f altogether.)
A simple solution (unfortunately needed per-client) is to setup an alias in your ~/.hgrc as follows:
[alias]
testboardpush = push -f ssh://example.com/testboard
You can then use hg testboardpush to push your commits to the automated testing repository, instead of getting into the bad habbit of using push -f.
If you have multiple repositories with multiple testboard locations, you can instead setup your alias inside your ~/.hgrc file as follows:
[alias]
testboardpush = push -f testboard
And then for each HG repository's .hg/hgrc file, have the lines:
[paths]
testboard = ssh://example.com/testboard
With this setup, typing hg testboardpush will always push to the correct place for the particular HG repository you are currently working in (or fail with an error if the path hasn't been setup).
Unfortunately, it does not appear you can do this from the server side without a custom version of HG; in particular, my reading of the push implementation in the localrepo.py file of the HG sources indicates it unconditionally checks for new heads using discovery.checkheads (and aborts) unless the force argument is set.
Related
We have a master repository located on a separate server. I originally cloned the default branch and made my changes locally. I have locally commited those changes. However, there has been a branch created on the master repository that I would like to push my changes to. Below is the description of my attempt at getting this accomplished.
I have cloned the branch. I am trying to export my changes from local default like so:
C:\hg\default>hg export -g -o mypatch -r tip
and when trying to import them into the clone of the new branch, I get the following:
C:\hg\newBranch>hg import C:\hg\default\mypatch
applying C:\hg\Fill1\mypatch
patching file .hgignore
Hunk #1 FAILED at 11
1 out of 1 hunks FAILED -- saving rejects to file .hgignore.rej
abort: patch failed to apply
I can manually fix the .hgingore.rej file just fine. The problem is that the patch also contains files that were moved. Instead of the files showing as moved, I get the following when running hg status:
C:\hg\newBranch>hg status -C
M someOtherFilesThatLookAsExpected.txt
! originalLocaion\fileA.txt
? newLocation\fileA.txt
This missing and new status is for all files that were moved in the commit contained the applied patch. Am I doing something wrong? Do I always have to manually move files when applying a patch? Is there an easier way to accomplish this branch transfer?
That's a bit difficult to answer without knowing more about your repository structure, but here's how I'd go about it without knowing more. I'm assuming that the reason for the conflict is that there are conflicting changes in the same branch of the repository.
First, get the contents of the newBranch repository:
cd c:\hg\default
hg pull c:\hg\newBranch
Then, either merge or rebase your changes on top. If you are working on the same branch, then just using
hg pull --rebase c:\hg\newBranch
in lieu of the regular pull should do (assuming you have rebasing enabled). Otherwise, do an explicit merge or rebase of the two heads that you need to reconcile. Finally, do:
hg push -r tip c:\hg\newBranch
in order to get your (now reconciled) changes back into newBranch.
Unless you have very specific and unusual requirements, push and pull should be your normal way to sync repositories or part of them (note that using -r will only push/pull the respective branch). Export/import are rather low-level mechanisms that may not give you the benefits of the standard machinery that handles renames, three-way merging logic, etc.
I have in some cases a need to enforce that Mercurial-users have run hg pull -u before any hg commit can be allowed, i.e., hg pull will mean that the incoming queue is empty — and furthermore I also want that the person is using the head version of the branch.
How can I set up such a restriction?
(I am fully aware that this goes against parts of the DVCS design core)
You could ask your developers to install
[hooks]
pre-commit = hg pull -u
in their config files (it should probably be installed in the per-repository .hg/hgrc file since this workflow is repository specific).
This makes Mercurial a little Subversion-like: your developers will only have one outstanding changeset. But note as soon as someone pushes to the server, hg pull -u cannot update to the new branch tip since it will cross branches (topological branches) to do so. So a proper merge will be needed at that point (or a rebase, see hg pull --rebase).
Normally mercurial will NOT let you push an open head to the server without using the -f flag (force). You can write a hook to pull automatically but that can not be enforced server side due to the server not knowing what you have. There is an article on mercurial's website about this scenario:
https://www.mercurial-scm.org/wiki/TipsAndTricks?highlight=%28heads%29#Prevent_a_push_that_would_create_multiple_heads
As Adam says, perhaps what you really need to do is prevent multiple heads (per branch). This is what we do, using the 'forbid_2head' hook from Netbeans (linked from here https://www.mercurial-scm.org/wiki/TipsAndTricks#Prevent_a_push_that_would_create_multiple_heads)
The result is that the hook prevents any push that creates multiple heads on a branch (so one on the anonymous/default branch plus one each on named branches). This effectively forces a pull before commit because you have to pull, get the two heads locally, then merge or rebase to remove it.
note, the hook is on the server/master repo
I use named branches in Mercurial.
In doing so I have created one branch called playground where I can try out various wacky experiments. I never intend to merge this branch into any others and I never want to push it to our main repository.
Since creating it, every time I do a push I am told I have added a new branch and I have to use the --new-branch flag. At this point hg push -b default (or whatever branch I'm pushing) works fine but it's annoying. Is there any way to suppress that message by letting Hg know that I am not interested in pushing that branch ever?
Starting with Mercurial 2.1 (released in February 2012), you can mark your changesets secret to keep them from being pushed to another repository. You use the new hg phase command to do this:
$ hg phase --force --secret .
This mark the current working directory parent revision (.) as being in the secret phase. Secret changesets are local to your repository: they wont be pushed or pulled. Pushing now looks like this:
$ hg push
pushing to /home/mg/tmp/repo
searching for changes
no changes to push but 2 secret changesets
There is no equivalent mechanism in older versions of Mercurial. There your best bet is to create a local clone for the changesets you don't want to push.
Update:
Mercurial 2.1 introduced the hg phase command which allows users to control what change sets are exchanged with remote repositories. #MartinGeisler answer to this question details this method.
Original Answer:
If you want to create a local branch of your code you have a couple options. You can hg clone the repository which will locally create a branch of the entire repository in your filesystem. The other alternative is you can try to use a Mercurial extension like LocalbranchExtension.
There are many ways to branch in Mercurial without using a named branch. Just find a method that suits your needs.
Further reading: http://stevelosh.com/blog/2009/08/a-guide-to-branching-in-mercurial/
In addition to the excellent answer above concerning phases, you can also specify 'default-path' (in the [paths] section of your .hgrc) to refer to the local repository:
[paths]
default = ...
default-push = .
This will cause all outgoing changesets to be compared to the specified repository. In this case, comparing outgoing changesets in your local repository TO your local repository results in nothing to push.
You can still pull/update/merge from the main repository, but no push will ever send anything back to that main repository.
If you work on multiple machines/repositories, you can set one up as described above, and configure the others to specify the 'default' path to point to the server that pushes to itself. In this way, the other machines can push/pull to your local central repository, and these changesets will never escape your carefully configured collection of repositories.
I am developing a web database that is already in use for about a dozen separate installations, most of which I also manage. Each installation has a fair bit of local configuration and customization. Having just switched to mercurial from svn, I would like to take advantage of its distributed nature to keep track of local modifications. I have set up each installed server as its own repo (and configured apache not to serve the .hg directories).
My difficulty is that the development tree also contains local configuration, and I want to avoid placing every bit of it in an unversioned config file. So, how do I set things up to avoid propagating local configuration to the master repo and to the installed copies?
Example: I have a long config.ini file that should be versioned and distributed. The "clean" version contains placeholders for the database connection parameters, and I don't want the development server's passwords to end up in the repositories for the installed copies. But now and then I'll make changes (e.g., new defaults) that I do need to propagate. There are several files in a similar situation.
The best I could work out so far involves installing mq and turning the local modifications into a patch (two patches, actually, with logically separate changesets). Every time I want to commit a regular changeset to the local repo, I need to pop all patches, commit the modifications, and re-apply the patches. When I'm ready to push to the master repo, I must again pop the patches, push, and re-apply them. This is all convoluted and error-prone.
The only other alternative I can see is to forget about push and only propagate changesets as patches, which seems like an even worse solution. Can someone suggest a better set-up? I can't imagine that this is such an unusual configuration, but I haven't found anything about it.
Edit: After following up on the suggestions here, I'm coming to the conclusion that named branches plus rebase provide a simple and workable solution. I've added a description in the form of my own answer. Please take a look.
From your comments, it looks like you are already familiar with the best practice for dealing with this: version a configuration template, and keep the actual configuration unversioned.
But since you aren't happy with that solution, here is another one you can try:
Mercurial 2.1 introduced the concept of Phases. The phase is changeset metadata marking it as "secret", "draft" or "public". Normally this metadata is used and manipulated automatically by mercurial and its extensions without the user needing to be aware of it.
However, if you made a changeset 1234 which you never want to push to other repositories, you can enforce this by manually marking it as secret like this:
hg phase --force --secret -r 1234
If you then try to push to another repository, it will be ignored with this warning:
pushing to http://example.com/some/other/repository
searching for changes
no changes found (ignored 1 secret changesets)
This solution allows you to
version the local configuration changes
prevent those changes from being pushed accidentally
merge your local changes with other changes which you pull in
The big downside is of course that you cannot push changes which you made on top of this secret changeset (because that would push the secret changeset along). You'll have to rebase any such changes before you can push them.
If the problem with a versioned template and an unversioned local copy is that changes to the template don't make it into the local copies, how about modifying your app to use an unversioned localconfig.ini and fallback to a versioned config.ini for missing parameters. This way new default parameters can be added to config.ini and be propagated into your app.
Having followed up on the suggestions here, I came to the conclusion that named branches plus rebase provide a simple and reliable solution. I've been using the following method for some time now and it works very well. Basically, the history around the local changes is separated into named branches which can be easily rearranged with rebase.
I use a branch local for configuration information. When all my repos support Phases, I'll mark the local branch secret; but the method works without it. local depends on default, but default does not depend on local so it can be pushed independently (with hg push -r default). Here's how it works:
Suppose the main line of development is in the default branch. (You could have more branches; this is for concreteness). There is a master (stable) repo that does not contain passwords etc.:
---o--o--o (default)
In each deployed (non-development) clone, I create a branch local and commit all local state to it.
...o--o--o (default)
\
L--L (local)
Updates from upstream will always be in default. Whenever I pull updates, I merge them into local (n is a sequence of new updates):
...o--o--o--n--n (default)
\ \
L--L--N (local)
The local branch tracks the evolution of default, and I can still return to old configurations if something goes wrong.
On the development server, I start with the same set-up: a local branch with config settings as above. This will never be pushed. But at the tip of local I create a third branch, dev. This is where new development happens.
...o--o (default)
\
L--L (local)
\
d--d--d (dev)
When I am ready to publish some features to the main repository, I first rebase the entire dev branch onto the tip of default:
hg rebase --source "min(branch('dev'))" --dest default --detach
The previous tree becomes:
...o--o--d--d--d (default)
\
L--L (local)
The rebased changesets now belong to branch default. (With feature branches, add --keepbranches to the rebase command to retain the branch name). The new features no longer have any ancestors in local, and I can publish them with push -r default without dragging along the local revisions. (Never merge from local into default; only the other way around). If you forget to say -r default when pushing, no problem: Your push gets rejected since it would add a new head.
On the development server, I merge the rebased revs into local as if I'd just pulled them:
...o--o--d--d--d (default)
\ \
L--L-----N (local)
I can now create a new dev branch on top of local, and continue development.
This has the benefits that I can develop on a version-controlled, configured setup; that I don't need to mess with patches; that previous configuration stages remain in the history (if my webserver stops working after an update, I can update back to a configured version); and that I only rebase once, when I'm ready to publish changes. The rebasing and subsequent merge might lead to conflicts if a revision conflicts with local configuration changes; but if that's going to happen, it's better if they occur when merge facilities can help resolve them.
1 Mercurial have (follow-up to comments) selective (string-based) commit - see Record Extension
2 Local changes inside versioned public files can be easy received with MQ Extension (I do it for site-configs all time). Your headache with MQ
Every time I want to commit a regular changeset to the local repo, I
need to pop all patches, commit the modifications, and re-apply the
patches. When I'm ready to push to the master repo, I must again pop
the patches, push, and re-apply them.
is a result of not polished workflow and (some) misinterpretation. If you want commit without MQ-patches - don't do it by hand. Add alias for commit, which qop -all + commit and use this new command only. And when you push, you may don't worry about MQ-state - you push changesets from repo, not WC state. Local repo can also be protected without alias by pre-commit hook checking content.
3 You can try LocalBranches extension, where your local changes stored inside local branches (and merge branches on changes) - I found this way more troublesome, compared to MQ
Is there any option to restrict a user to use hg push -f? Because it will remove intermediate commits by other users.
First of all, doing hg push -f cannot remove intermediate commits. Mercurial is built around an append-only history model and you cannot delete stuff from a server by pushing to it.
When a user does hg push -f, then he tells Mercurial to go ahead with the push even though it creates new remote heads. To prevent this, you need a hook on the server that forbids more than a single head. There are listed several such hooks here.
With Mercurial 1.6, it is no longer necessary to use -f when you push a new named branch. You should instead use hg push --new-branch. This is safer since it only allows the creation of new branches, not the creation of multiple remote heads.