This commit introduces the new go-libp2p-gorpc streaming capabilities for
Cluster. The main aim is to work towards heavily reducing memory usage when
working with very large pinsets.
As a side-effect, it takes the chance to revampt all types for all public
methods so that pointers to static what should be static objects are not used
anymore. This should heavily reduce heap allocations and GC activity.
The main change is that state.List now returns a channel from which to read
the pins, rather than pins being all loaded into a huge slice.
Things reading pins have been all updated to iterate on the channel rather
than on the slice. The full pinset is no longer fully loaded onto memory for
things that run regularly like StateSync().
Additionally, the /allocations endpoint of the rest API no longer returns an
array of pins, but rather streams json-encoded pin objects directly. This
change has extended to the restapi client (which puts pins into a channel as
they arrive) and to ipfs-cluster-ctl.
There are still pending improvements like StatusAll() calls which should also
stream responses, and specially BlockPut calls which should stream blocks
directly into IPFS on a single call.
These are coming up in future commits.
This does 3 things:
- Add a NoPin option to the adder. When set to true, the adding process does not
send a pin in the end.
- When user-allocations are set and local=true happens, we do not overwrite
the allocations returned by the allocator to include the local peer
anymore, as this could alter user-allocations.
- Some code improvement (remove pointers).
Local dagservice is not really a local as it add to other peers as well.
It is a dagservice that does not perform sharding. Since we are going to
have a local dagservice(one that adds only to the local peer), renaming
this `single` dagservice
