sharding: Package comments and responding to PR feedback

Former-commit-id: 970a229ed8d1cce8c5383a40e313092828c1be69 [formerly 0f30c11d3352946caccc1d325a0551f43dc8439c]
Former-commit-id: 6ca7badf14c01fabf6a63db26214b6a0179aa8f2

sharding/client/client.go

@@ -1,3 +1,6 @@
+// Package client provides an interface for interacting with a running ethereum full node.
+// As part of the initial phases of sharding, actors will need access to the sharding management
+// contract on the main PoW chain.
 package client
 
 import (
@@ -7,6 +10,7 @@ import (
 	"fmt"
 	"math/big"
 	"os"
+	"time"
 
 	ethereum "github.com/ethereum/go-ethereum"
 
@@ -17,8 +21,10 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/ethclient"
+	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/node"
 	"github.com/ethereum/go-ethereum/rpc"
+	"github.com/ethereum/go-ethereum/sharding"
 	"github.com/ethereum/go-ethereum/sharding/contracts"
 	cli "gopkg.in/urfave/cli.v1"
 )
@@ -27,7 +33,7 @@ const (
 	clientIdentifier = "geth" // Used to determine the ipc name.
 )
 
-// General Client for Collator. Communicates to Geth node via JSON RPC.
+// General client for Collator/Proposer. Communicates to Geth node via JSON RPC.
 
 type shardingClient struct {
 	endpoint  string             // Endpoint to JSON RPC
@@ -189,3 +195,45 @@ func dialRPC(endpoint string) (*rpc.Client, error) {
 	}
 	return rpc.Dial(endpoint)
 }
+
+// initSMC initializes the sharding manager contract bindings.
+// If the SMC does not exist, it will be deployed.
+func initSMC(c *shardingClient) (*contracts.SMC, error) {
+	b, err := c.client.CodeAt(context.Background(), sharding.ShardingManagerAddress, nil)
+	if err != nil {
+		return nil, fmt.Errorf("unable to get contract code at %s: %v", sharding.ShardingManagerAddress, err)
+	}
+
+	// Deploy SMC for development only.
+	// TODO: Separate contract deployment from the sharding client. It would only need to be deployed
+	// once on the mainnet, so this code would not need to ship with the client.
+	if len(b) == 0 {
+		log.Info(fmt.Sprintf("No sharding manager contract found at %s. Deploying new contract.", sharding.ShardingManagerAddress.String()))
+
+		txOps, err := c.CreateTXOps(big.NewInt(0))
+		if err != nil {
+			return nil, fmt.Errorf("unable to intiate the transaction: %v", err)
+		}
+
+		addr, tx, contract, err := contracts.DeploySMC(txOps, c.client)
+		if err != nil {
+			return nil, fmt.Errorf("unable to deploy sharding manager contract: %v", err)
+		}
+
+		for pending := true; pending; _, pending, err = c.client.TransactionByHash(context.Background(), tx.Hash()) {
+			if err != nil {
+				return nil, fmt.Errorf("unable to get transaction by hash: %v", err)
+			}
+			time.Sleep(1 * time.Second)
+		}
+
+		log.Info(fmt.Sprintf("New contract deployed at %s", addr.String()))
+		return contract, nil
+	}
+
+	contract, err := contracts.NewSMC(sharding.ShardingManagerAddress, c.client)
+	if err != nil {
+
+	}
+	return contract, nil
+}

sharding/client/smc.go

@@ -1,54 +0,0 @@
-package client
-
-import (
-	"context"
-	"fmt"
-	"math/big"
-	"time"
-
-	"github.com/ethereum/go-ethereum/log"
-	"github.com/ethereum/go-ethereum/sharding"
-	"github.com/ethereum/go-ethereum/sharding/contracts"
-)
-
-// initSMC initializes the sharding manager contract bindings.
-// If the SMC does not exist, it will be deployed.
-func initSMC(c *shardingClient) (*contracts.SMC, error) {
-	b, err := c.client.CodeAt(context.Background(), sharding.ShardingManagerAddress, nil)
-	if err != nil {
-		return nil, fmt.Errorf("unable to get contract code at %s: %v", sharding.ShardingManagerAddress, err)
-	}
-
-	// Deploy SMC for development only.
-	// TODO: Separate contract deployment from the sharding client. It would only need to be deployed
-	// once on the mainnet, so this code would not need to ship with the client.
-	if len(b) == 0 {
-		log.Info(fmt.Sprintf("No sharding manager contract found at %s. Deploying new contract.", sharding.ShardingManagerAddress.String()))
-
-		txOps, err := c.CreateTXOps(big.NewInt(0))
-		if err != nil {
-			return nil, fmt.Errorf("unable to intiate the transaction: %v", err)
-		}
-
-		addr, tx, contract, err := contracts.DeploySMC(txOps, c.client)
-		if err != nil {
-			return nil, fmt.Errorf("unable to deploy sharding manager contract: %v", err)
-		}
-
-		for pending := true; pending; _, pending, err = c.client.TransactionByHash(context.Background(), tx.Hash()) {
-			if err != nil {
-				return nil, fmt.Errorf("unable to get transaction by hash: %v", err)
-			}
-			time.Sleep(1 * time.Second)
-		}
-
-		log.Info(fmt.Sprintf("New contract deployed at %s", addr.String()))
-		return contract, nil
-	}
-
-	contract, err := contracts.NewSMC(sharding.ShardingManagerAddress, c.client)
-	if err != nil {
-		return nil, fmt.Errorf("failed to create sharding contract: %v", err)
-	}
-	return contract, nil
-}

sharding/collator/collator.go

@@ -8,6 +8,7 @@ import (
 	"github.com/ethereum/go-ethereum/accounts/abi/bind"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/log"
+	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/sharding"
 	"github.com/ethereum/go-ethereum/sharding/client"
 )
@@ -120,3 +121,22 @@ func submitCollation(shardID int64) error {
 	log.Info("Submit collation function called")
 	return nil
 }
+
+// joinCollatorPool checks if the account is a collator in the SMC. If
+// the account is not in the set, it will deposit 100ETH into contract.
+func joinCollatorPool(c client.Client) error {
+
+	log.Info("Joining collator pool")
+	txOps, err := c.CreateTXOps(sharding.DepositSize)
+	if err != nil {
+		return fmt.Errorf("unable to intiate the deposit transaction: %v", err)
+	}
+
+	tx, err := c.SMCTransactor().Deposit(txOps)
+	if err != nil {
+		return fmt.Errorf("unable to deposit eth and become a collator: %v", err)
+	}
+	log.Info(fmt.Sprintf("Deposited %dETH into contract with transaction hash: %s", new(big.Int).Div(sharding.DepositSize, big.NewInt(params.Ether)), tx.Hash().String()))
+
+	return nil
+}

sharding/collator/collator_client.go

@@ -1,3 +1,4 @@
+// Package collator holds all of the functionality to run as a collator in a sharded system.
 package collator
 
 import (
@@ -6,7 +7,9 @@ import (
 	cli "gopkg.in/urfave/cli.v1"
 )
 
+// Collator runnable client.
 type Collator interface {
+	// Start the main routine for a collator.
 	Start() error
 }
 

sharding/collator/smc.go

@@ -1,30 +0,0 @@
-package collator
-
-import (
-	"fmt"
-	"math/big"
-
-	"github.com/ethereum/go-ethereum/log"
-	"github.com/ethereum/go-ethereum/params"
-	"github.com/ethereum/go-ethereum/sharding"
-	"github.com/ethereum/go-ethereum/sharding/client"
-)
-
-// joinCollatorPool checks if the account is a collator in the SMC. If
-// the account is not in the set, it will deposit 100ETH into contract.
-func joinCollatorPool(c client.Client) error {
-
-	log.Info("Joining collator pool")
-	txOps, err := c.CreateTXOps(sharding.DepositSize)
-	if err != nil {
-		return fmt.Errorf("unable to intiate the deposit transaction: %v", err)
-	}
-
-	tx, err := c.SMCTransactor().Deposit(txOps)
-	if err != nil {
-		return fmt.Errorf("unable to deposit eth and become a collator: %v", err)
-	}
-	log.Info(fmt.Sprintf("Deposited %dETH into contract with transaction hash: %s", new(big.Int).Div(sharding.DepositSize, big.NewInt(params.Ether)), tx.Hash().String()))
-
-	return nil
-}

sharding/contracts/contracts.go

@@ -0,0 +1,5 @@
+// Package contracts consists of generated contracts for sharding.
+package contracts
+
+// DO NOT USE THIS FILE: It exists only for the package comment. Other files in this package are
+// automatically generated and cannot have a package comment.

sharding/proposer/proposer_client.go

@@ -1,3 +1,5 @@
+// Package proposer holds all of the functionality to run as a collation proposer in a sharded
+// system.
 package proposer
 
 import (