comparison mercurial/localrepo.py @ 39996:dbcb466d0065

localrepo: define storage backend in creation options (API)

We add an experimental config option to define the storage backend
for new repositories. By default, it uses "revlogv1," which maps to
the current and only modern supported repository format.

We add a "backend" creation option to control which backend to
use. It defaults to using the value from the config option.

newreporequirements() will now barf if it sees a "backend" value
that isn't "revlogv1." This forces extensions to monkeypatch the
function to handle requirements derivation for custom backends.

In order for this to "just work," we factored out obtaining the
default creation options into its own function and made callers
of newreporequirements() responsible for passing in valid data.
Without this, direct callers of newreporequirements() wouldn't
get the proper results.

Differential Revision: https://phab.mercurial-scm.org/D4791

39995:582676acaf6d

    return makelocalrepository(ui, localpath, intents=intents)

def islocal(path):
    return True

def newreporequirements(ui, createopts=None):
    """Determine the set of requirements for a new local repository.

    Extensions can wrap this function to specify custom requirements for
    new repositories.
    """
    createopts = createopts or {}

    # If the repo is being created from a shared repository, we copy
    # its requirements.
    if 'sharedrepo' in createopts:
        requirements = set(createopts['sharedrepo'].requirements)
        if createopts.get('sharedrelative'):
            requirements.add('relshared')
        else:
            requirements.add('shared')

        return requirements

    requirements = {'revlogv1'}
    if ui.configbool('format', 'usestore'):
        requirements.add('store')
        if ui.configbool('format', 'usefncache'):

    Extensions can wrap this function to filter out creation options
    they know how to handle.
    """
    known = {
        'narrowfiles',
        'sharedrepo',
        'sharedrelative',
        'shareditems',
    }

    ``path`` path to the new repo's working directory.
    ``createopts`` options for the new repository.

    The following keys for ``createopts`` are recognized:

    narrowfiles
       Set up repository to support narrow file storage.
    sharedrepo
       Repository object from which storage should be shared.
    sharedrelative

       stored as relative. By default, the pointer to the "parent" repo
       is stored as an absolute path.
    shareditems
       Set of items to share to the new repository (in addition to storage).
    """
    createopts = createopts or {}

    unknownopts = filterknowncreateopts(ui, createopts)

    if not isinstance(unknownopts, dict):
        raise error.ProgrammingError('filterknowncreateopts() did not return '

39996:dbcb466d0065

    return makelocalrepository(ui, localpath, intents=intents)

def islocal(path):
    return True

def defaultcreateopts(ui, createopts=None):
    """Populate the default creation options for a repository.

    A dictionary of explicitly requested creation options can be passed
    in. Missing keys will be populated.
    """
    createopts = dict(createopts or {})

    if 'backend' not in createopts:
        # experimental config: storage.new-repo-backend
        createopts['backend'] = ui.config('storage', 'new-repo-backend')

    return createopts

def newreporequirements(ui, createopts):
    """Determine the set of requirements for a new local repository.

    Extensions can wrap this function to specify custom requirements for
    new repositories.
    """
    # If the repo is being created from a shared repository, we copy
    # its requirements.
    if 'sharedrepo' in createopts:
        requirements = set(createopts['sharedrepo'].requirements)
        if createopts.get('sharedrelative'):
            requirements.add('relshared')
        else:
            requirements.add('shared')

        return requirements

    if 'backend' not in createopts:
        raise error.ProgrammingError('backend key not present in createopts; '
                                     'was defaultcreateopts() called?')

    if createopts['backend'] != 'revlogv1':
        raise error.Abort(_('unable to determine repository requirements for '
                            'storage backend: %s') % createopts['backend'])

    requirements = {'revlogv1'}
    if ui.configbool('format', 'usestore'):
        requirements.add('store')
        if ui.configbool('format', 'usefncache'):

    Extensions can wrap this function to filter out creation options
    they know how to handle.
    """
    known = {
        'backend',
        'narrowfiles',
        'sharedrepo',
        'sharedrelative',
        'shareditems',
    }

    ``path`` path to the new repo's working directory.
    ``createopts`` options for the new repository.

    The following keys for ``createopts`` are recognized:

    backend
       The storage backend to use.
    narrowfiles
       Set up repository to support narrow file storage.
    sharedrepo
       Repository object from which storage should be shared.
    sharedrelative

       stored as relative. By default, the pointer to the "parent" repo
       is stored as an absolute path.
    shareditems
       Set of items to share to the new repository (in addition to storage).
    """
    createopts = defaultcreateopts(ui, createopts=createopts)

    unknownopts = filterknowncreateopts(ui, createopts)

    if not isinstance(unknownopts, dict):
        raise error.ProgrammingError('filterknowncreateopts() did not return '