Partial download by filepath with mercurial - mercurial

How do you download a specific folder from a Mercurial repo? This is a similar question to partial cloning, but I don't want to actually create a local repo, since I won't be versioning these files. I just want to quickly download a specific folder containing a few KB worth of files from a repo that's several hundreds MB in size.
Specifically, I want to download all the entire "examples/plugins" folder from the Gazebo project.
I've tried searching hg's manpage and Google, but all my searches keep bringing me back to pages that assume I want to create a full repo and make a partial clone or narrow clone, which hg doesn't support.

If the Mercurial repository is running hgweb, it's possible to download a specific folder remotely. For example for the official hg repository, you can download https://www.mercurial-scm.org/repo/hg/archive/REVISION.tar.bz2/SUBPATH/.
Example: https://www.mercurial-scm.org/repo/hg/archive/19c5b0913960.tar.bz2/contrib/
This uses the 'hg archive' functionality Edward mentions, but through the web-interface.

Related

How can I see my original source code on the server Mercurial repository?

I'm a novice in Mercurial and Phabricator.
I cannot see my source code on the server repository.
How can I see my original source code on my Mercurial repository?
I mean that if I want to compile the code on the server, which files will be used?
You can't manipulate files directly in repository as files (they doesn't exist as FS-object) - and this is true for all and any SCM.
You have to extract files from repository as unversioned tree into some location (hg help archive) or have Working Directory with files (hg help up), because usually servver-side repositories are "bare", with empty Working Directory.
Best (and standard) way to do it - use server-side hooks

Mercurial to Manage Existing Website?

Getting ready to launch a website/project that was in beta testing. I want to switch it over to version control (Mercurial since I'm familiar with it).
Problem is, I am not sure how to go about doing it since the code on the website is already up and in-use and how to deal with the directories I do not need to manage (vendor and web/Upload).
Whats the best way to go about this?
Would I put the entire site into a folder, init a Merc repo, use hgignore to not track vendor and web/Upload, commit, then clone it to the live server?
Thanks! Just confused on what to do since the site is live and has user uploads.
I'm assuming you want to turn the website directory on your web server into a Mercurial repository. If that's the case, you would create a new repository somewhere on that computer, then move the .hg directory in the new repository into the website directory you want to be the root of the repository. You should then be able to run
hg add * --exclude vendor --exclude web/Upload
hg commit -m "Adding site to version control."
to get all the non-user files into version control.
I recommend, however, that you write a script or investigate tools that will deploy your website out of a repository outside your web root. You don't want your .hg directory exposed to the world. Until you get a deploy script/tool working, make sure you tell your webserver to prohibit/reject all requests to your .hg directory.

When using Mercurial HG, how to just get the latest code?

I am new to Mercurial HG. My friends created a repo and I am going to use it.
I installed TortoiseHG and trying to get the latest code. I found that when using Clone operation, it will pull all code to my local, including the histories (Am I right?). This is not needed for me. I just wanna get the latest code. Is there an operation for this?
In short, no.
In a bit longer: Mercurial doesn't yet support “shallow” clones where you only get part of the history. So each time you clone you pull in the entire repository with all changesets.
Additionally, unlike Subversion, there is no way to make a “narrow” clone where you only checkout a portion of a repository. For example, if a repository has directories foo/ and bar/, there is no way to get only the bar/ directory. In other words, Mercurial always operates on project-wide snapshots.
The easiest way to achieve what you want:
hg archive [destination folder]
Once you cloned a repository, to get the code of the "tip" (the last version of the current branch - the default one if not precised) you just need to update.
You have an update action in TortoiseHG. Once done, you can look at the files in the folder.
If you wanted another state of the repository (an old version, or an old tagged state) then it's still the update command, with other parametters (see the docs or the TortoiseHG interface).
If you only want the latest code, and you don't intend to do anything related to the repository with it, like commit, or diff to older versions, or whatever, then you it depends on where you got the code from and how.
If he is using one of the hosting services, like bitbucket, there's usually a download link which gives you just the source code.
For instance, if you go here, there's a "Get source" link up and to the right which gives you a few choices in the file format (zip or whatnot.)
If you got the files somewhere else, you need to explore the interface you got them from. Try just pasting the link you cloned from into your browser and see what you get.
Sure. Clone the repository, then delete the .hg subdirectory.
I might be a bit late but actually it is possible to forget some history with Mercurial. You just need to enable convert extension from Your mercurial.ini file or .hgrc file.
[extensions]
hgext.convert=
Now you are able to use convert extension to "clone" only changesets starting from the revision specified.
hg convert --config convert.hg.startrev=[wheretostart] path_to_full_history_repo path_to_new_repo
Just note that this is not the same operation with hg clone. That's why the source repository must be a local repository. For example if we have a repository in folder MyProject and we want to forget all the changes done before revision 100. We can use the following command:
hg convert --config convert.hg.startrev=[100] MyProject MyShrinkedProject
If You are going to use this shrunken repository on a "central server" remember to take care of that everybody clones it before they continue working. Repositories are not compatible with each other anymore.
Mercurial now supports shallow clone using remotefilelog extension. Extension is bundled with mercurial probably since version 4.9. Older versions need to download the extension e.g. from github.
You have to enable it on the server e.g:
[extensions]
remotefilelog =
[remotefilelog]
server = True
serverexpiration = 14
and on client
[extensions]
remotefilelog =
[remotefilelog]
cachepath = /some/path
cachelimit = 5 GB
Than you can do shallow clone with much smaller footprint a and faster clone speed:
hg clone --shallow ssh://user#server/repo

Using Mercurial via a USB flash drive

In short:
How can I use Hg to synchronize repositories between two computers using a flash drive as intermediary?
With more detail:
I often develop code on computers that aren't networked in any way, and I transfer files between these machines using a USB flash drive. Now I would like to develop some software across these machines using Hg repositories on each machine that I can frequently sync-up using the flash drive transfer mechanism.
I'm slightly familiar with Hg, as I use it in the most simple way possible for versioning only my own work on independent machines, but am uncertain as to exactly what I should do to use it to synchronize repositories between two computers using a flash drive as intermediary. Maybe, for example, I need to create a temporary repository on the flash drive (using “clone”) from which I then sync to (using “push” and “pull”), and do this by A→flash, flash→B, B→flash, flash→A? The more specificity in your answer regarding the sequence of actions and commands, the more useful to me.
Finally, how do I get this process started? Do I need to do something so Hg knows these are all part of one code base? For example, each of my current repositories on the different computers was created independently from a time before I started using Hg, and although all the code is similar, independent changes have been made to each, and the repositories know nothing about each other. If what I need to do with this is different than what I need to do for the ongoing case once I have everything unified, spelling this process out for me as well would also help.
In case it's important, these machines can be running any of Windows, Mac, or Linux, and my versions of Mercurial are slightly different on each machine (though the Mercurial versions could be unified if needed).
What you have described above in terms of using the flash drive as an intermediate storage location should work. My process would be:
initial setup
create repo on computer A (using hg init)
clone the repo from computer A to flash drive
hg clone C:/path/to/repo/A X:/path/to/flash/drive/repo
clone the repo from flash drive to computer B
hg clone X:/path/to/flash/drive/repo C:/path/to/repo/B
working process
edit/commit to repo on computer A
push from computer A to flash drive
hg push X:/path/to/flash/drive/repo
pull from flash drive to computer B
hg pull X:/path/to/flash/drive/repo
edit/commit repo on computer B
push from computer B to flash drive (same commands as above)
pull from flash drive to computer A (same commands as above)
Finally, how do I get this process
started? Do I need to do something so
Hg knows these are all part of one
code base?
Mercurial knows if two arbitrary repositories have a common ancestor by looking at the SHA1 hash keys of the commits in each repo. In other words, assuming both repos have at least one common hash key in their histories, Mercurial will attempt to merge them. In your specific case, where both repos are initially un-versioned, Mercurial will need some help. The best thing to do would be to get to a place where both repos are identical and then perform your hg init. Mercurial should handle sharing from this point on.
When working offline on different machines. It is better to use the bundle command that comes with Mercurial. So echoing what dls wrote but a slight change process.
Initial setup as mentioned by dls.
or
Go to your Mercurial repository top directory
Create bundle: hg bundle --base null ../project.hg
Copy the project.hg file to your other computer
Create a directory there
Make it an Mercurial repository : hg init
Incorporate the bundle: hg pull <path/project.hg>
hg update
Check hg log, both the repository will show same base revisions and tip
Workflow using bundle
I use a slightly different workflow. I keep these repositories as distinct repositories.
I mention them as repo1 and repo2.
Suppose that the current tip of repo1 is 4f45839f613c.
You make changes and commit them in repo1
Create a bundle of the changes :
Command : This bundle contains all changes since the specified base version.
hg bundle --base 4f45839f613c changes.bundle
Take it to repo2 by copying the bundle.
You can simply pull the bundle to repo2 :
Command :
hg pull changes.bundle
If the bundle contains changes that are already present in repo2, then these will be ignored when pulling. As long as the bundle doesn't grow to large, this allows to use the bundle command with the same --base revision again and again to create bundles including further changes.
About bundles: these are (very well) compressed.
creates a (compressed) backup of the repository
hg bundle --base null backup.bundle
[Edit : Adding some links on this topic]
http://blog.experimentalworks.net/2010/09/review-remote-changes-offline-in-mercurial/
https://www.mercurial-scm.org/wiki/Bundle
[Edit: What I think is advantage of using bundle]
Bundles can be created offline, copied or sent via mail. Using push to repo on flash drive, requires it to be connected. Bundles are easier since it does not maintain that the two repo from which you push and pull have to be available at the same time.
Apart from that, bundles can also be of two types : Changesets and Incremental. Changeset bundles are complete standalone bundles. You can also use bundles for backup as a single file.

What's the best way to get a copy of the tip of a mercurial repository?

I want to do the equivalent of svn export REMOTE_URL with a mercurial repository. What I want at the end is an unversioned snapshot of the repository at the remote URL, but without cloning all of the changesets over to my local machine.
Also, I want to be able to specify a tag in the remote repository to pick this from. If it's not obvious, I'm building a release management tool that pulls from a canonical mercurial repository to build a release file, and it's slow right now because some projects have large, multiple-version binary files committed.
Is this possible? How would one go about it?
Its usually easier (if the remote HG is using the hgweb interface) to just visit the repo in your browser and download a .tgz / .zip / .bz2 of the tip revision. You'll see the links if the remote HG supports this.
If you want the repository, you need all of the revisions that went into the current tip for it to be at all functional.
There are options to hg clone that allow you to fetch a repository up to a certain revision, but none (that I could find) that allow you to get just the tip revision. What you are essentially asking for is a snapshot of the repo.
Edit: To Get A Snapshot
hg clone http[s]://url.to.repo repo.hg
cd repo.hg
hg archive ../repo-snapshot
cd ..
rm -rf repo.hg
The snapshot is now in repo-snapshot.
Yes, this does entail cloning the repo first, which is why I suggested seeing if the remote hgweb supports on the fly downloads of any particular revision. If it does, your problem is solved with something like curl or wget instead of HG.
If not, its good to let the original repo 'live' since you can update it again later via hg pull, then create another snapshot of a future release. This saves having to start over from scratch when cloning, especially for large repositories with lots of changes.
Also, Linux centric, but you get the gist. Of course, replace http[s] with the desired protocol as needed.
Is there any reason you can't maintain a mirror (updated in the background however often you want) of the remote repository on your local machine, then have the release management tool on your local machine run hg archive out of the local clone as necessary? If your concern is user-responsiveness, and not total bandwidth/storage consumed, this offsets the "slow" part to where you won't see it.
Tim Post noted that if you do have the hgweb CGI interface available, you can configure it to pull compressed archives down and unpack them (and the interface is consistent enough that you could script that via wget), but if you don't, core Mercurial doesn't have a lot of tools to help you, and the developers have expressed an opposition to trying to turn Mercurial into a general rsync-type client.
If you aren't afraid of playing with unofficial add-ons, you could have a look at the FTP Extension. That will force you to push from the server, however.