Use goreleaser to build and release (#244)

Instead of using gox on one side and an action to release, we can merge
them together with goreleaser which will build for extra targets (arm,
mips if needed in the future) and it also takes care of creating
checksums, a source archive, and a changelog and creating a release with
all the artifacts.

All binaries should respect the old naming convention, so any scripts
out there should still work.

Signed-off-by: Itxaka <igarcia@suse.com>

vendor/google.golang.org/grpc/internal/resolver/config_selector.go

@@ -0,0 +1,164 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package resolver provides internal resolver-related functionality.
+package resolver
+
+import (
+	"context"
+	"sync"
+
+	"google.golang.org/grpc/internal/serviceconfig"
+	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/resolver"
+)
+
+// ConfigSelector controls what configuration to use for every RPC.
+type ConfigSelector interface {
+	// Selects the configuration for the RPC, or terminates it using the error.
+	// This error will be converted by the gRPC library to a status error with
+	// code UNKNOWN if it is not returned as a status error.
+	SelectConfig(RPCInfo) (*RPCConfig, error)
+}
+
+// RPCInfo contains RPC information needed by a ConfigSelector.
+type RPCInfo struct {
+	// Context is the user's context for the RPC and contains headers and
+	// application timeout.  It is passed for interception purposes and for
+	// efficiency reasons.  SelectConfig should not be blocking.
+	Context context.Context
+	Method  string // i.e. "/Service/Method"
+}
+
+// RPCConfig describes the configuration to use for each RPC.
+type RPCConfig struct {
+	// The context to use for the remainder of the RPC; can pass info to LB
+	// policy or affect timeout or metadata.
+	Context      context.Context
+	MethodConfig serviceconfig.MethodConfig // configuration to use for this RPC
+	OnCommitted  func()                     // Called when the RPC has been committed (retries no longer possible)
+	Interceptor  ClientInterceptor
+}
+
+// ClientStream is the same as grpc.ClientStream, but defined here for circular
+// dependency reasons.
+type ClientStream interface {
+	// Header returns the header metadata received from the server if there
+	// is any. It blocks if the metadata is not ready to read.
+	Header() (metadata.MD, error)
+	// Trailer returns the trailer metadata from the server, if there is any.
+	// It must only be called after stream.CloseAndRecv has returned, or
+	// stream.Recv has returned a non-nil error (including io.EOF).
+	Trailer() metadata.MD
+	// CloseSend closes the send direction of the stream. It closes the stream
+	// when non-nil error is met. It is also not safe to call CloseSend
+	// concurrently with SendMsg.
+	CloseSend() error
+	// Context returns the context for this stream.
+	//
+	// It should not be called until after Header or RecvMsg has returned. Once
+	// called, subsequent client-side retries are disabled.
+	Context() context.Context
+	// SendMsg is generally called by generated code. On error, SendMsg aborts
+	// the stream. If the error was generated by the client, the status is
+	// returned directly; otherwise, io.EOF is returned and the status of
+	// the stream may be discovered using RecvMsg.
+	//
+	// SendMsg blocks until:
+	//   - There is sufficient flow control to schedule m with the transport, or
+	//   - The stream is done, or
+	//   - The stream breaks.
+	//
+	// SendMsg does not wait until the message is received by the server. An
+	// untimely stream closure may result in lost messages. To ensure delivery,
+	// users should ensure the RPC completed successfully using RecvMsg.
+	//
+	// It is safe to have a goroutine calling SendMsg and another goroutine
+	// calling RecvMsg on the same stream at the same time, but it is not safe
+	// to call SendMsg on the same stream in different goroutines. It is also
+	// not safe to call CloseSend concurrently with SendMsg.
+	SendMsg(m interface{}) error
+	// RecvMsg blocks until it receives a message into m or the stream is
+	// done. It returns io.EOF when the stream completes successfully. On
+	// any other error, the stream is aborted and the error contains the RPC
+	// status.
+	//
+	// It is safe to have a goroutine calling SendMsg and another goroutine
+	// calling RecvMsg on the same stream at the same time, but it is not
+	// safe to call RecvMsg on the same stream in different goroutines.
+	RecvMsg(m interface{}) error
+}
+
+// ClientInterceptor is an interceptor for gRPC client streams.
+type ClientInterceptor interface {
+	// NewStream produces a ClientStream for an RPC which may optionally use
+	// the provided function to produce a stream for delegation.  Note:
+	// RPCInfo.Context should not be used (will be nil).
+	//
+	// done is invoked when the RPC is finished using its connection, or could
+	// not be assigned a connection.  RPC operations may still occur on
+	// ClientStream after done is called, since the interceptor is invoked by
+	// application-layer operations.  done must never be nil when called.
+	NewStream(ctx context.Context, ri RPCInfo, done func(), newStream func(ctx context.Context, done func()) (ClientStream, error)) (ClientStream, error)
+}
+
+// ServerInterceptor is unimplementable; do not use.
+type ServerInterceptor interface {
+	notDefined()
+}
+
+type csKeyType string
+
+const csKey = csKeyType("grpc.internal.resolver.configSelector")
+
+// SetConfigSelector sets the config selector in state and returns the new
+// state.
+func SetConfigSelector(state resolver.State, cs ConfigSelector) resolver.State {
+	state.Attributes = state.Attributes.WithValues(csKey, cs)
+	return state
+}
+
+// GetConfigSelector retrieves the config selector from state, if present, and
+// returns it or nil if absent.
+func GetConfigSelector(state resolver.State) ConfigSelector {
+	cs, _ := state.Attributes.Value(csKey).(ConfigSelector)
+	return cs
+}
+
+// SafeConfigSelector allows for safe switching of ConfigSelector
+// implementations such that previous values are guaranteed to not be in use
+// when UpdateConfigSelector returns.
+type SafeConfigSelector struct {
+	mu sync.RWMutex
+	cs ConfigSelector
+}
+
+// UpdateConfigSelector swaps to the provided ConfigSelector and blocks until
+// all uses of the previous ConfigSelector have completed.
+func (scs *SafeConfigSelector) UpdateConfigSelector(cs ConfigSelector) {
+	scs.mu.Lock()
+	defer scs.mu.Unlock()
+	scs.cs = cs
+}
+
+// SelectConfig defers to the current ConfigSelector in scs.
+func (scs *SafeConfigSelector) SelectConfig(r RPCInfo) (*RPCConfig, error) {
+	scs.mu.RLock()
+	defer scs.mu.RUnlock()
+	return scs.cs.SelectConfig(r)
+}

vendor/google.golang.org/grpc/internal/resolver/dns/dns_resolver.go

@@ -32,7 +32,9 @@ import (
 	"sync"
 	"time"
 
+	grpclbstate "google.golang.org/grpc/balancer/grpclb/state"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/internal/backoff"
 	"google.golang.org/grpc/internal/envconfig"
 	"google.golang.org/grpc/internal/grpcrand"
 	"google.golang.org/grpc/resolver"
@@ -43,6 +45,15 @@ import (
 // addresses from SRV records.  Must not be changed after init time.
 var EnableSRVLookups = false
 
+var logger = grpclog.Component("dns")
+
+// Globals to stub out in tests. TODO: Perhaps these two can be combined into a
+// single variable for testing the resolver?
+var (
+	newTimer           = time.NewTimer
+	newTimerDNSResRate = time.NewTimer
+)
+
 func init() {
 	resolver.Register(NewBuilder())
 }
@@ -140,7 +151,6 @@ func (b *dnsBuilder) Build(target resolver.Target, cc resolver.ClientConn, opts
 
 	d.wg.Add(1)
 	go d.watcher()
-	d.ResolveNow(resolver.ResolveNowOptions{})
 	return d, nil
 }
 
@@ -198,28 +208,38 @@ func (d *dnsResolver) Close() {
 
 func (d *dnsResolver) watcher() {
 	defer d.wg.Done()
+	backoffIndex := 1
 	for {
-		select {
-		case <-d.ctx.Done():
-			return
-		case <-d.rn:
-		}
-
 		state, err := d.lookup()
 		if err != nil {
+			// Report error to the underlying grpc.ClientConn.
 			d.cc.ReportError(err)
 		} else {
-			d.cc.UpdateState(*state)
+			err = d.cc.UpdateState(*state)
 		}
 
-		// Sleep to prevent excessive re-resolutions. Incoming resolution requests
-		// will be queued in d.rn.
-		t := time.NewTimer(minDNSResRate)
+		var timer *time.Timer
+		if err == nil {
+			// Success resolving, wait for the next ResolveNow. However, also wait 30 seconds at the very least
+			// to prevent constantly re-resolving.
+			backoffIndex = 1
+			timer = newTimerDNSResRate(minDNSResRate)
+			select {
+			case <-d.ctx.Done():
+				timer.Stop()
+				return
+			case <-d.rn:
+			}
+		} else {
+			// Poll on an error found in DNS Resolver or an error received from ClientConn.
+			timer = newTimer(backoff.DefaultExponential.Backoff(backoffIndex))
+			backoffIndex++
+		}
 		select {
-		case <-t.C:
 		case <-d.ctx.Done():
-			t.Stop()
+			timer.Stop()
 			return
+		case <-timer.C:
 		}
 	}
 }
@@ -251,7 +271,7 @@ func (d *dnsResolver) lookupSRV() ([]resolver.Address, error) {
 				return nil, fmt.Errorf("dns: error parsing A record IP address %v", a)
 			}
 			addr := ip + ":" + strconv.Itoa(int(s.Port))
-			newAddrs = append(newAddrs, resolver.Address{Addr: addr, Type: resolver.GRPCLB, ServerName: s.Target})
+			newAddrs = append(newAddrs, resolver.Address{Addr: addr, ServerName: s.Target})
 		}
 	}
 	return newAddrs, nil
@@ -271,7 +291,7 @@ func handleDNSError(err error, lookupType string) error {
 	err = filterError(err)
 	if err != nil {
 		err = fmt.Errorf("dns: %v record lookup error: %v", lookupType, err)
-		grpclog.Infoln(err)
+		logger.Info(err)
 	}
 	return err
 }
@@ -294,7 +314,7 @@ func (d *dnsResolver) lookupTXT() *serviceconfig.ParseResult {
 
 	// TXT record must have "grpc_config=" attribute in order to be used as service config.
 	if !strings.HasPrefix(res, txtAttribute) {
-		grpclog.Warningf("dns: TXT record %v missing %v attribute", res, txtAttribute)
+		logger.Warningf("dns: TXT record %v missing %v attribute", res, txtAttribute)
 		// This is not an error; it is the equivalent of not having a service config.
 		return nil
 	}
@@ -326,13 +346,15 @@ func (d *dnsResolver) lookup() (*resolver.State, error) {
 	if hostErr != nil && (srvErr != nil || len(srv) == 0) {
 		return nil, hostErr
 	}
-	state := &resolver.State{
-		Addresses: append(addrs, srv...),
+
+	state := resolver.State{Addresses: addrs}
+	if len(srv) > 0 {
+		state = grpclbstate.Set(state, &grpclbstate.State{BalancerAddresses: srv})
 	}
 	if !d.disableServiceConfig {
 		state.ServiceConfig = d.lookupTXT()
 	}
-	return state, nil
+	return &state, nil
 }
 
 // formatIP returns ok = false if addr is not a valid textual representation of an IP address.
@@ -418,12 +440,12 @@ func canaryingSC(js string) string {
 	var rcs []rawChoice
 	err := json.Unmarshal([]byte(js), &rcs)
 	if err != nil {
-		grpclog.Warningf("dns: error parsing service config json: %v", err)
+		logger.Warningf("dns: error parsing service config json: %v", err)
 		return ""
 	}
 	cliHostname, err := os.Hostname()
 	if err != nil {
-		grpclog.Warningf("dns: error getting client hostname: %v", err)
+		logger.Warningf("dns: error getting client hostname: %v", err)
 		return ""
 	}
 	var sc string

vendor/google.golang.org/grpc/internal/resolver/unix/unix.go

@@ -0,0 +1,63 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package unix implements a resolver for unix targets.
+package unix
+
+import (
+	"fmt"
+
+	"google.golang.org/grpc/internal/transport/networktype"
+	"google.golang.org/grpc/resolver"
+)
+
+const unixScheme = "unix"
+const unixAbstractScheme = "unix-abstract"
+
+type builder struct {
+	scheme string
+}
+
+func (b *builder) Build(target resolver.Target, cc resolver.ClientConn, _ resolver.BuildOptions) (resolver.Resolver, error) {
+	if target.Authority != "" {
+		return nil, fmt.Errorf("invalid (non-empty) authority: %v", target.Authority)
+	}
+	addr := resolver.Address{Addr: target.Endpoint}
+	if b.scheme == unixAbstractScheme {
+		// prepend "\x00" to address for unix-abstract
+		addr.Addr = "\x00" + addr.Addr
+	}
+	cc.UpdateState(resolver.State{Addresses: []resolver.Address{networktype.Set(addr, "unix")}})
+	return &nopResolver{}, nil
+}
+
+func (b *builder) Scheme() string {
+	return b.scheme
+}
+
+type nopResolver struct {
+}
+
+func (*nopResolver) ResolveNow(resolver.ResolveNowOptions) {}
+
+func (*nopResolver) Close() {}
+
+func init() {
+	resolver.Register(&builder{scheme: unixScheme})
+	resolver.Register(&builder{scheme: unixAbstractScheme})
+}