added ability to calculate multihashes

will be updating dependencies in the following commit

docs/IPFS_ISSUES.md

@@ -1 +1,4 @@
-https://github.com/ipfs/go-ipfs/issues/2509
+https://github.com/ipfs/go-ipfs/issues/2509
+
+* Pinning happens in sequence, this can cause issues with many processings
+    > trying to pin one content, and upload another content

docs/LINKS.md

@@ -72,4 +72,9 @@ https://github.com/ipfs/go-dnslink
 
 
 IPFS Configuration Explanation:
-https://github.com/ipfs/go-ipfs/blob/master/docs/config.md
+https://github.com/ipfs/go-ipfs/blob/master/docs/config.
+
+
+calculate ipfs hashes https://discuss.ipfs.io/t/how-to-calculate-file-directory-hash/777/48
+
+Debugging https://github.com/ipfs/go-ipfs/blob/master/docs/debug-guide.md

utils/multihash.go

@@ -0,0 +1,36 @@
+package utils
+
+import (
+	"os"
+
+	"github.com/ipsn/go-ipfs/core"
+	"github.com/ipsn/go-ipfs/core/coreunix"
+	"github.com/ipsn/go-ipfs/gxlibs/github.com/ipfs/go-blockservice"
+	datastore "github.com/ipsn/go-ipfs/gxlibs/github.com/ipfs/go-datastore"
+	blockstore "github.com/ipsn/go-ipfs/gxlibs/github.com/ipfs/go-ipfs-blockstore"
+	offline "github.com/ipsn/go-ipfs/gxlibs/github.com/ipfs/go-ipfs-exchange-offline"
+	"github.com/ipsn/go-ipfs/gxlibs/github.com/ipfs/go-merkledag"
+	"github.com/ipsn/go-ipfs/pin"
+)
+
+// GenerateIpfsMultiHashForFile is used to calculate an IPFS multihash
+// for a given file, without actually broadcasting it to the network
+// or even adding it at all. It was graciously adopted thanks to @hinshun
+// over on discuss.ipfs.io. Overtime we willallow calculating different hash types
+func GenerateIpfsMultiHashForFile(fileName string) (string, error) {
+	dstore := datastore.NewMapDatastore()
+	bstore := blockstore.NewBlockstore(dstore)
+	bserv := blockservice.New(bstore, offline.Exchange(bstore))
+	dserv := merkledag.NewDAGService(bserv)
+	n := &core.IpfsNode{
+		Blockstore: blockstore.NewGCBlockstore(bstore, blockstore.NewGCLocker()),
+		Pinning:    pin.NewPinner(dstore, dserv, dserv),
+		DAG:        dserv,
+	}
+	fileHandler, err := os.Open(fileName)
+	if err != nil {
+		return "", err
+	}
+
+	return coreunix.Add(n, fileHandler)
+}

utils/multihash_test.go

@@ -0,0 +1,18 @@
+package utils_test
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/RTradeLtd/Temporal/utils"
+)
+
+var testFile = "/tmp/test.txt"
+
+func TestGenerateIpfsMultiHashForFile(t *testing.T) {
+	hash, err := utils.GenerateIpfsMultiHashForFile(testFile)
+	if err != nil {
+		t.Fatal(err)
+	}
+	fmt.Println("recovered hash is ", hash)
+}