all: import "context" instead of "golang.org/x/net/context"

There is no need to depend on the old context package now that the
minimum Go version is 1.7. The move to "context" eliminates our weird
vendoring setup. Some vendored code still uses golang.org/x/net/context
and it is now vendored in the normal way.

This change triggered new vet checks around context.WithTimeout which
didn't fire with golang.org/x/net/context.

Author: fjl

accounts/abi/bind/backend.go

@@ -17,13 +17,13 @@
 package bind
 
 import (
+	"context"
 	"errors"
 	"math/big"
 
 	"github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
-	"golang.org/x/net/context"
 )
 
 var (

accounts/abi/bind/backends/simulated.go

@@ -17,6 +17,7 @@
 package backends
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"math/big"
@@ -34,7 +35,6 @@ import (
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/pow"
-	"golang.org/x/net/context"
 )
 
 // Default chain configuration which sets homestead phase at block 0 (i.e. no frontier)

accounts/abi/bind/base.go

@@ -17,6 +17,7 @@
 package bind
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"math/big"
@@ -26,7 +27,6 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/crypto"
-	"golang.org/x/net/context"
 )
 
 // SignerFn is a signer function callback when a contract requires a method to

accounts/abi/bind/util.go

@@ -17,13 +17,13 @@
 package bind
 
 import (
+	"context"
 	"fmt"
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/log"
-	"golang.org/x/net/context"
 )
 
 // WaitMined waits for tx to be mined on the blockchain.

accounts/abi/bind/util_test.go

@@ -17,6 +17,7 @@
 package bind_test
 
 import (
+	"context"
 	"math/big"
 	"testing"
 	"time"
@@ -27,7 +28,6 @@ import (
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/crypto"
-	"golang.org/x/net/context"
 )
 
 var testKey, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")

accounts/usbwallet/ledger_wallet.go

@@ -21,6 +21,7 @@
 package usbwallet
 
 import (
+	"context"
 	"encoding/binary"
 	"encoding/hex"
 	"errors"
@@ -38,7 +39,6 @@ import (
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/karalabe/hid"
-	"golang.org/x/net/context"
 )
 
 // Maximum time between wallet health checks to detect USB unplugs.

build/_vendor/src/golang.org/x/net/LICENSE

@@ -1,18 +1,3 @@
-# Vendored Dependencies
-
-Dependencies are almost all vendored in at the standard Go `/vendor` path. This allows
-people to build go-ethereum using the standard toolchain without any particular package
-manager. It also plays nicely with `go get`, not requiring external code to be relied on.
-
-The one single dependent package missing from `vendor` is `golang.org/x/net/context`. As
-this is a package exposed via public library APIs, it must not be vendored as dependent
-code woulnd't be able to instantiate.
-
-To allow reproducible builds of go-ethereum nonetheless that don't need network access
-during build time to fetch `golang.org/x/net/context`, a version was copied into our repo
-at the very specific `/build/_vendor` path, which is added automatically by all CI build
-scripts and the makefile too.
-
 # Debian Packaging
 
 Tagged releases and develop branch commits are available as installable Debian packages

build/ci-notes.md

@@ -26,6 +26,7 @@ package chequebook
 
 import (
 	"bytes"
+	"context"
 	"crypto/ecdsa"
 	"encoding/json"
 	"fmt"
@@ -43,7 +44,6 @@ import (
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/swarm/services/swap/swap"
-	"golang.org/x/net/context"
 )
 
 // TODO(zelig): watch peer solvency and notify of bouncing cheques

contracts/chequebook/cheque.go

@@ -20,6 +20,7 @@ package release
 //go:generate abigen --sol ./contract.sol --pkg release --out ./contract.go
 
 import (
+	"context"
 	"fmt"
 	"strings"
 	"time"
@@ -33,7 +34,6 @@ import (
 	"github.com/ethereum/go-ethereum/node"
 	"github.com/ethereum/go-ethereum/p2p"
 	"github.com/ethereum/go-ethereum/rpc"
-	"golang.org/x/net/context"
 )
 
 // Interval to check for new releases
@@ -116,47 +116,49 @@ func (r *ReleaseService) checker() {
 
 	for {
 		select {
-		// If the time arrived, check for a new release
 		case <-timer.C:
 			// Rechedule the timer before continuing
 			timer.Reset(releaseRecheckInterval)
-
-			// Retrieve the current version, and handle missing contracts gracefully
-			ctx, _ := context.WithTimeout(context.Background(), time.Second*5)
-			opts := &bind.CallOpts{Context: ctx}
-			version, err := r.oracle.CurrentVersion(opts)
-			if err != nil {
-				if err == bind.ErrNoCode {
-					log.Debug("Release oracle not found", "contract", r.config.Oracle)
-					continue
-				}
-				log.Error("Failed to retrieve current release", "err", err)
-				continue
-			}
-			// Version was successfully retrieved, notify if newer than ours
-			if version.Major > r.config.Major ||
-				(version.Major == r.config.Major && version.Minor > r.config.Minor) ||
-				(version.Major == r.config.Major && version.Minor == r.config.Minor && version.Patch > r.config.Patch) {
-
-				warning := fmt.Sprintf("Client v%d.%d.%d-%x seems older than the latest upstream release v%d.%d.%d-%x",
-					r.config.Major, r.config.Minor, r.config.Patch, r.config.Commit[:4], version.Major, version.Minor, version.Patch, version.Commit[:4])
-				howtofix := fmt.Sprintf("Please check https://github.com/ethereum/go-ethereum/releases for new releases")
-				separator := strings.Repeat("-", len(warning))
-
-				log.Warn(separator)
-				log.Warn(warning)
-				log.Warn(howtofix)
-				log.Warn(separator)
-			} else {
-				log.Debug("Client seems up to date with upstream",
-					"local", fmt.Sprintf("v%d.%d.%d-%x", r.config.Major, r.config.Minor, r.config.Patch, r.config.Commit[:4]),
-					"upstream", fmt.Sprintf("v%d.%d.%d-%x", version.Major, version.Minor, version.Patch, version.Commit[:4]))
-			}
-
-		// If termination was requested, return
+			r.checkVersion()
 		case errc := <-r.quit:
 			errc <- nil
 			return
 		}
 	}
 }
+
+func (r *ReleaseService) checkVersion() {
+	// Retrieve the current version, and handle missing contracts gracefully
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second*5)
+	opts := &bind.CallOpts{Context: ctx}
+	defer cancel()
+
+	version, err := r.oracle.CurrentVersion(opts)
+	if err != nil {
+		if err == bind.ErrNoCode {
+			log.Debug("Release oracle not found", "contract", r.config.Oracle)
+		} else {
+			log.Error("Failed to retrieve current release", "err", err)
+		}
+		return
+	}
+	// Version was successfully retrieved, notify if newer than ours
+	if version.Major > r.config.Major ||
+		(version.Major == r.config.Major && version.Minor > r.config.Minor) ||
+		(version.Major == r.config.Major && version.Minor == r.config.Minor && version.Patch > r.config.Patch) {
+
+		warning := fmt.Sprintf("Client v%d.%d.%d-%x seems older than the latest upstream release v%d.%d.%d-%x",
+			r.config.Major, r.config.Minor, r.config.Patch, r.config.Commit[:4], version.Major, version.Minor, version.Patch, version.Commit[:4])
+		howtofix := fmt.Sprintf("Please check https://github.com/ethereum/go-ethereum/releases for new releases")
+		separator := strings.Repeat("-", len(warning))
+
+		log.Warn(separator)
+		log.Warn(warning)
+		log.Warn(howtofix)
+		log.Warn(separator)
+	} else {
+		log.Debug("Client seems up to date with upstream",
+			"local", fmt.Sprintf("v%d.%d.%d-%x", r.config.Major, r.config.Minor, r.config.Patch, r.config.Commit[:4]),
+			"upstream", fmt.Sprintf("v%d.%d.%d-%x", version.Major, version.Minor, version.Patch, version.Commit[:4]))
+	}
+}

contracts/release/release.go

@@ -19,6 +19,7 @@ package eth
 import (
 	"bytes"
 	"compress/gzip"
+	"context"
 	"errors"
 	"fmt"
 	"io"
@@ -39,7 +40,6 @@ import (
 	"github.com/ethereum/go-ethereum/miner"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/rlp"
-	"golang.org/x/net/context"
 )
 
 const defaultTraceTimeout = 5 * time.Second

eth/api.go

@@ -17,6 +17,7 @@
 package eth
 
 import (
+	"context"
 	"math/big"
 
 	"github.com/ethereum/go-ethereum/accounts"
@@ -33,7 +34,6 @@ import (
 	"github.com/ethereum/go-ethereum/internal/ethapi"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/rpc"
-	"golang.org/x/net/context"
 )
 
 // EthApiBackend implements ethapi.Backend for full nodes

eth/api_backend.go

@@ -17,6 +17,7 @@
 package eth
 
 import (
+	"context"
 	"math/big"
 
 	"github.com/ethereum/go-ethereum"
@@ -26,7 +27,6 @@ import (
 	"github.com/ethereum/go-ethereum/internal/ethapi"
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/ethereum/go-ethereum/rpc"
-	"golang.org/x/net/context"
 )
 
 // ContractBackend implements bind.ContractBackend with direct calls to Ethereum

eth/bind.go

@@ -17,12 +17,12 @@
 package downloader
 
 import (
+	"context"
 	"sync"
 
 	ethereum "github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/rpc"
-	"golang.org/x/net/context"
 )
 
 // PublicDownloaderAPI provides an API which gives information about the current synchronisation status.

eth/downloader/api.go

@@ -17,15 +17,14 @@
 package filters
 
 import (
+	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
 	"math/big"
 	"sync"
 	"time"
 
-	"golang.org/x/net/context"
-
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/core/types"

eth/filters/api.go

@@ -17,18 +17,17 @@
 package filters
 
 import (
+	"context"
 	"math"
-	"time"
-
 	"math/big"
+	"time"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/rpc"
-	"golang.org/x/net/context"
 )
 
 type Backend interface {

eth/filters/filter.go

@@ -19,6 +19,7 @@
 package filters
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"sync"
@@ -29,7 +30,6 @@ import (
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/rpc"
-	"golang.org/x/net/context"
 )
 
 // Type determines the kind of filter and is used to put the filter in to
@@ -372,7 +372,8 @@ func (es *EventSystem) lightFilterNewHead(newHeader *types.Header, callBack func
 func (es *EventSystem) lightFilterLogs(header *types.Header, addresses []common.Address, topics [][]common.Hash, remove bool) []*types.Log {
 	if bloomFilter(header.Bloom, addresses, topics) {
 		// Get the logs of the block
-		ctx, _ := context.WithTimeout(context.Background(), time.Second*5)
+		ctx, cancel := context.WithTimeout(context.Background(), time.Second*5)
+		defer cancel()
 		receipts, err := es.backend.GetReceipts(ctx, header.Hash())
 		if err != nil {
 			return nil

eth/filters/filter_system.go

@@ -17,13 +17,12 @@
 package filters
 
 import (
+	"context"
 	"math/big"
 	"reflect"
 	"testing"
 	"time"
 
-	"golang.org/x/net/context"
-
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/types"