GitLab

Improved the repo migration errors to provide instructions
to the user.

WARNING: No migration performed! That needs to come in a separate
commit, perhaps amended into this one.

Migration must move keyspace "/b" from leveldb to the flatfs subdir,
while removing the "b" prefix (keys should start with just "/").

This allows replacing the datastore without needing to write Close
through to every wrapped datastore.

FSRepo.Open is dead since fdd1cd8d

We now consider debugerrors harmful: we've run into cases where
debugerror.Wrap() hid valuable error information (err == io.EOF?).
I've removed them from the main code, but left them in some tests.
Go errors are lacking, but unfortunately, this isn't the solution.

It is possible that debugerros.New or debugerrors.Errorf should
remain still (i.e. only remove debugerrors.Wrap) but we don't use
these errors often enough to keep.

- Modified Godeps/Godeps.json by hand
- [TEST] Updated welcome docs hash to sharness
- [TEST] Updated contact doc
- [TEST] disabled breaking test (t0080-repo refs local)

There is no way this was safe before.

Be careful to unlock on the error paths.

No code attempts to open the same repo multiple times.

Error handling is still buggy, but it's starting to get clearer.

repo.Once now does refcounts on a whole Repo level, returning the same
pointer to multiple Openers. This removes the need for the weird model
of separate FSRepo instances pointing to the same underlying storage,
and the races caused by that.

This will replace the elaborate refcounting in fsrepo, to make it
easier to maintain.

Nobody calls At without immediately calling Open.

First step, a mechanical transformation. Cleanups will follow.

This is only called from `ipfs` command line tool well before it opens
the repo. The behavior change here causes a false positive if the
current process has already opened the repo. That's a bit late to ask
this question, anyway, and is not expected to have ever triggered.

The only caller is `ipfs init`, which at that time does not hold a
repository open, and refuses to run on existing repos anyway.

now, eventlogger works wherever the fsrepo is used

"for each desired change, make the change easy (warning: this may be
hard), then make the easy change" - Kent Beck

https://twitter.com/KentBeck/status/250733358307500032

http://martinfowler.com/articles/preparatory-refactoring-example.html

cc @jbenet @whyrusleeping