hgext/infinitepush/indexapi.py

context: introduce p[12]copies() methods and debugp[12]copies commands

As mentioned earlier, I'm working on support for storing copy metadata
in the changeset instead of in the filelog.

In order to transition a repo from storing metadata in filelogs to
storing it in the changeset, I'm going to provide a config option for
reading the metadata from the changeset, but falling back to getting
it from the filelog if it's not in the changeset. In this compatiblity
mode, the changeset-optmized algorithms will be used. We will then
need to convert the filelog copy metadata to look like that provided
by changeset copy metadata. This patch introduces methods that do just
that.

By having these methods here, we can start writing changeset-optimized
algorithms that should work already before we add any support for
storing the metadata in the changesets.

This commit also includes new debugp[12]copies commands and exercises
them in test-copies.t.

Differential Revision: https://phab.mercurial-scm.org/D5990

# Infinite push
#
# Copyright 2016 Facebook, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

class indexapi(object):
    """Class that manages access to infinitepush index.

    This class is a context manager and all write operations (like
    deletebookmarks, addbookmark etc) should use `with` statement:

      with index:
          index.deletebookmarks(...)
          ...
    """

    def __init__(self):
        """Initializes the metadata store connection."""

    def close(self):
        """Cleans up the metadata store connection."""

    def __enter__(self):
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        pass

    def addbundle(self, bundleid, nodesctx):
        """Takes a bundleid and a list of node contexts for each node
        in that bundle and records that."""
        raise NotImplementedError()

    def addbookmark(self, bookmark, node):
        """Takes a bookmark name and hash, and records mapping in the metadata
        store."""
        raise NotImplementedError()

    def addmanybookmarks(self, bookmarks):
        """Takes a dict with mapping from bookmark to hash and records mapping
        in the metadata store."""
        raise NotImplementedError()

    def deletebookmarks(self, patterns):
        """Accepts list of bookmarks and deletes them.
        """
        raise NotImplementedError()

    def getbundle(self, node):
        """Returns the bundleid for the bundle that contains the given node."""
        raise NotImplementedError()

    def getnode(self, bookmark):
        """Returns the node for the given bookmark. None if it doesn't exist."""
        raise NotImplementedError()

    def getbookmarks(self, query):
        """Returns bookmarks that match the query"""
        raise NotImplementedError()

    def saveoptionaljsonmetadata(self, node, jsonmetadata):
        """Saves optional metadata for a given node"""
        raise NotImplementedError()

class indexexception(Exception):
    pass