Obsolete markers wide-usage and propagation should be avoided by default until
the obsolete feature is more mature.
This changeset introduce the `_enable` variable and prevent the creation of
obsolete marker if the feature is set to `False` (the default).
More limitation comes in followup changesets.
Obsolete markers are now exchanged in smaller pieces that fit in a http header.
This changes is done to avoid 400 bad request error when exchanging obsolete
puskey over http.
The last key pushed is always hold by the "dump0" key to ensure an easy place to
hook for people who need it.
The function is now able to write the version header as necessary. The function
now yield bytes to be written to a stream.
This should ease later use of this function for wireprotocol based exchanged.
Prepare the public use of the writemarker by wireprotocol function.
This function yield every nodes which succeed to a group of nodes.
The first user will be checkheads who need to know if we push successors for
remote extra heads.
Marker are now written as soon as possible but within a transaction. Using a
transaction ensure a proper behavior on error and rollback compatibility.
Flush logic are not necessary anymore and are dropped from lock release.
With this changeset, the obsstore is open, written and closed for every single
added marker. This is expected to be highly inefficient and batched write should
be implemented "quickly".
Another issue is that every flush of the file will invalidate the obsstore
filecache and trigger a full re instantiation of the repo.obsstore attribute
(including, reading and parsing entry). This is also expected to be highly
inefficient and proper filecache operation should be implemented "quickly" too.
A side benefit of the filecache issue is that repo.obsstore object is properly
invalidated on transaction abortion.
This is the second step toward incremental writing of marker inside a
transaction. The obsstore file is now handled append only.
Header writing have been extracted from _writemarkers.
Because the _writemarkers method have been dropped, the push code
directly reuse the serialised content of local repo `listkeys`. This
is not very pretty, but this part of the protocol still need major
improvement anyway.
This is the first step toward incremental writing of obsolete marker within a
transaction.
For this purpose, obsstore is now given its repo sopener. This make it able to
handles read and write to the obsstore file itself. Most IO logic is removed
from localrepo and handled by obsstore object directly.
An `obsolete` boolean property is added to changeset context. Function to get
obsolete marker object from a changeset context are added to the obsolete
module.
