kubo/exchange/offline/offline.go
Henry 92d08db7a5 rewrote import paths of go.net/context to use golang.org/x/context
- updated go-ctxgroup and goprocess
ctxgroup: AddChildGroup was changed to AddChild. Used in two files:
- p2p/net/mock/mock_net.go
- routing/dht/dht.go

- updated context from hg repo to git
prev. commit in hg was ad01a6fcc8a19d3a4478c836895ffe883bd2ceab. (context: make parentCancelCtx iterative)
represents commit 84f8955a887232b6308d79c68b8db44f64df455c in git repo

- updated context to master (b6fdb7d8a4ccefede406f8fe0f017fb58265054c)

Aaron Jacobs (2):
net/context: Don't accept a context in the DoSomethingSlow example.
context: Be clear that users must cancel the result of WithCancel.

Andrew Gerrand (1):
go.net: use golang.org/x/... import paths

Bryan C. Mills (1):
net/context: Don't leak goroutines in Done example.

Damien Neil (1):
context: fix removal of cancelled timer contexts from parent

David Symonds (2):
context: Fix WithValue example code.
net: add import comments.

Sameer Ajmani (1):
context: fix TestAllocs to account for ints in interfaces
2015-02-25 11:58:19 +01:00

69 lines
1.8 KiB
Go

// package offline implements an object that implements the exchange
// interface but returns nil values to every request.
package offline
import (
context "github.com/jbenet/go-ipfs/Godeps/_workspace/src/golang.org/x/net/context"
blocks "github.com/jbenet/go-ipfs/blocks"
"github.com/jbenet/go-ipfs/blocks/blockstore"
exchange "github.com/jbenet/go-ipfs/exchange"
u "github.com/jbenet/go-ipfs/util"
)
func Exchange(bs blockstore.Blockstore) exchange.Interface {
return &offlineExchange{bs: bs}
}
// offlineExchange implements the Exchange interface but doesn't return blocks.
// For use in offline mode.
type offlineExchange struct {
bs blockstore.Blockstore
}
// GetBlock returns nil to signal that a block could not be retrieved for the
// given key.
// NB: This function may return before the timeout expires.
func (e *offlineExchange) GetBlock(_ context.Context, k u.Key) (*blocks.Block, error) {
return e.bs.Get(k)
}
// HasBlock always returns nil.
func (e *offlineExchange) HasBlock(_ context.Context, b *blocks.Block) error {
return e.bs.Put(b)
}
// Close always returns nil.
func (_ *offlineExchange) Close() error {
// NB: exchange doesn't own the blockstore's underlying datastore, so it is
// not responsible for closing it.
return nil
}
func (e *offlineExchange) GetBlocks(ctx context.Context, ks []u.Key) (<-chan *blocks.Block, error) {
out := make(chan *blocks.Block, 0)
go func() {
defer close(out)
var misses []u.Key
for _, k := range ks {
hit, err := e.bs.Get(k)
if err != nil {
misses = append(misses, k)
// a long line of misses should abort when context is cancelled.
select {
// TODO case send misses down channel
case <-ctx.Done():
return
default:
continue
}
}
select {
case out <- hit:
case <-ctx.Done():
return
}
}
}()
return out, nil
}