propose collation called on geteligibleproposer

Former-commit-id: 0a23d54aa3006d103bb7123bcfe0ac2ca3a2b027 [formerly 7266cc53ca4d6826b4a54d30391f9c5e5b0b7d10]
Former-commit-id: 6b33ca471ede8696fc83285ae426645308a4c6fe

sharding/collator.go

@@ -6,6 +6,7 @@ import (
 	"github.com/ethereum/go-ethereum/accounts/abi/bind"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/log"
+	"math/big"
 )
 
 // subscribeBlockHeaders checks incoming block headers and determines if
@@ -51,27 +52,23 @@ func watchShards(c *Client, head *types.Header) error {
 		return fmt.Errorf("cannot unlock account. %v", err)
 	}
 
-	ops := bind.CallOpts{}
-	count, err := c.vmc.VMCCaller.ShardCount(&ops)
-	if err != nil {
-		return fmt.Errorf("unable to fetch shard count. %v", err)
-	}
-
+	log.Info(fmt.Sprint("watching shards..."))
 	s := 0
-	for s < int(count.Int64()) {
+	for s < shardCount {
 		// Checks if we are an eligible proposer according to the VMC
-		addr, err := c.vmc.VMCCaller.GetEligibleProposer(&ops, big.NewInt(s))
-		if err != nil {
-			return fmt.Errorf("cannot fetch eligible collation proposer. %v", err)
-		}
-		// if the address is the coinbase addr (current node running the sharding
-		// clint, then we propose a new collation)
-		if addr == accounts[0].Address {
-			err := proposeCollation()
+		ops := bind.CallOpts{}
+		period := head.Number.Div(head.Number, big.NewInt(int64(periodLength)))
+		addr, err := c.vmc.VMCCaller.GetEligibleProposer(&ops, big.NewInt(int64(s)), period)
+
+		// If output is non-empty and the addr == coinbase
+		if err == nil && addr == accounts[0].Address {
+			log.Info(fmt.Sprintf("selected as collator on shard %d", s))
+			err := proposeCollation(s)
 			if err != nil {
 				return fmt.Errorf("could not propose collation. %v", err)
 			}
 		}
+
 		s++
 	}
 
@@ -104,6 +101,6 @@ func proposeCollation(shardID int) error {
 	// This functions will fetch the transactions in the txpool and and apply
 	// them to finish up the collation. It will then need to broadcast the
 	// collation to the main chain using JSON-RPC.
-
+	log.Info(fmt.Sprint("propose collation called"))
 	return nil
 }

sharding/collator_test.go

@@ -1,11 +1,19 @@
 package sharding
 
 import (
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"sync"
 	"testing"
 )
 
-func TestDeposit(t *testing.T) {
-	if 0 != 0 {
-		t.Errorf("test incorrect")
-	}
+// FakeEthService based on implementation of internal/ethapi.Client
+type FakeEthService struct {
+	mu sync.Mutex
+
+	getCodeResp hexutil.Bytes
+	getCodeErr  error
+}
+
+func TestSubscribeHeaders(t *testing.T) {
+
 }

sharding/vmc.go

@@ -97,7 +97,7 @@ func initVMCValidator(c *Client) error {
 		},
 	}
 
-	_, err := c.vmc.VMCTransactor.Deposit(&ops, accounts[0].Address)
+	_, err := c.vmc.VMCTransactor.Deposit(&ops)
 	if err != nil {
 		return fmt.Errorf("unable to deposit eth and become a validator: %v", err)
 	}