merge origin

README.md

@@ -7,18 +7,17 @@
 
 > :heart: [**Uptrace.dev** - distributed traces, logs, and errors in one place](https://uptrace.dev)
 
-- [Docs](https://redis.uptrace.dev)
+- Join [Discord](https://discord.gg/rWtp5Aj) to ask questions.
+- [Documentation](https://redis.uptrace.dev)
 - [Reference](https://pkg.go.dev/github.com/go-redis/redis/v8?tab=doc)
 - [Examples](https://pkg.go.dev/github.com/go-redis/redis/v8?tab=doc#pkg-examples)
 - [RealWorld example app](https://github.com/uptrace/go-treemux-realworld-example-app)
-- Join [Discord](https://discord.gg/rWtp5Aj) to ask questions.
 
 ## Ecosystem
 
-- [redisext](https://github.com/go-redis/redisext) - tracing using OpenTelemetryHook.
+- [Distributed Locks](https://github.com/bsm/redislock).
 - [Redis Cache](https://github.com/go-redis/cache).
 - [Rate limiting](https://github.com/go-redis/redis_rate).
-- [Distributed Locks](https://github.com/bsm/redislock).
 
 ## Features
 
@@ -40,18 +39,18 @@
 
 ## Installation
 
-go-redis requires a Go version with [Modules](https://github.com/golang/go/wiki/Modules) support and
-uses import versioning. So please make sure to initialize a Go module before installing go-redis:
+go-redis supports 2 last Go versions and requires a Go version with
+[modules](https://github.com/golang/go/wiki/Modules) support. So make sure to initialize a Go
+module:
 
 ```shell
 go mod init github.com/my/repo
-go get github.com/go-redis/redis/v8
 ```
 
-Import:
+And then install go-redis (note _v8_ in the import; omitting it is a popular mistake):
 
-```go
-import "github.com/go-redis/redis/v8"
+```shell
+go get github.com/go-redis/redis/v8
 ```
 
 ## Quickstart
@@ -64,24 +63,13 @@ import (
 
 var ctx = context.Background()
 
-func ExampleNewClient() {
-    rdb := redis.NewClient(&redis.Options{
-        Addr:     "localhost:6379",
-        Password: "", // no password set
-        DB:       0,  // use default DB
-    })
-
-    pong, err := rdb.Ping(ctx).Result()
-    fmt.Println(pong, err)
-    // Output: PONG <nil>
-}
-
 func ExampleClient() {
     rdb := redis.NewClient(&redis.Options{
         Addr:     "localhost:6379",
         Password: "", // no password set
         DB:       0,  // use default DB
     })
+
     err := rdb.Set(ctx, "key", "value", 0).Err()
     if err != nil {
         panic(err)
@@ -106,11 +94,6 @@ func ExampleClient() {
 }
 ```
 
-## Howto
-
-Please go through [examples](https://pkg.go.dev/github.com/go-redis/redis/v8?tab=doc#pkg-examples)
-to get an idea how to use this package.
-
 ## Look and feel
 
 Some corner cases:

extra/rediscensus/go.mod

@@ -0,0 +1,11 @@
+module github.com/go-redis/redis/extra/rediscensus
+
+go 1.15
+
+replace github.com/go-redis/redis/extra/rediscmd => ../rediscmd
+
+require (
+	github.com/go-redis/redis/extra/rediscmd v0.1.0
+	github.com/go-redis/redis/v8 v8.3.2
+	go.opencensus.io v0.22.5
+)

extra/rediscensus/rediscensus.go

@@ -0,0 +1,45 @@
+package rediscensus
+
+import (
+	"context"
+
+	"github.com/go-redis/redis/extra/rediscmd"
+	"github.com/go-redis/redis/v8"
+	"go.opencensus.io/trace"
+)
+
+type TracingHook struct{}
+
+var _ redis.Hook = TracingHook{}
+
+func (TracingHook) BeforeProcess(ctx context.Context, cmd redis.Cmder) (context.Context, error) {
+	ctx, span := trace.StartSpan(ctx, cmd.FullName())
+	span.AddAttributes(trace.StringAttribute("db.system", "redis"),
+		trace.StringAttribute("redis.cmd", rediscmd.CmdString(cmd)))
+
+	return ctx, nil
+}
+
+func (TracingHook) AfterProcess(ctx context.Context, cmd redis.Cmder) error {
+	span := trace.FromContext(ctx)
+	if err := cmd.Err(); err != nil {
+		recordErrorOnOCSpan(ctx, span, err)
+	}
+	span.End()
+	return nil
+}
+
+func (TracingHook) BeforeProcessPipeline(ctx context.Context, cmds []redis.Cmder) (context.Context, error) {
+	return ctx, nil
+}
+
+func (TracingHook) AfterProcessPipeline(ctx context.Context, cmds []redis.Cmder) error {
+	return nil
+}
+
+func recordErrorOnOCSpan(ctx context.Context, span *trace.Span, err error) {
+	if err != redis.Nil {
+		span.AddAttributes(trace.BoolAttribute("error", true))
+		span.Annotate([]trace.Attribute{trace.StringAttribute("Error", "redis error")}, err.Error())
+	}
+}

extra/rediscmd/go.mod

@@ -0,0 +1,9 @@
+module github.com/go-redis/redis/extra/rediscmd
+
+go 1.15
+
+require (
+	github.com/go-redis/redis/v8 v8.3.2
+	github.com/onsi/ginkgo v1.14.2
+	github.com/onsi/gomega v1.10.3
+)

extra/rediscmd/rediscmd.go

@@ -0,0 +1,149 @@
+package rediscmd
+
+import (
+	"encoding/hex"
+	"fmt"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/go-redis/redis/v8"
+)
+
+func CmdString(cmd redis.Cmder) string {
+	b := make([]byte, 0, 32)
+	b = AppendCmd(b, cmd)
+	return String(b)
+}
+
+func CmdsString(cmds []redis.Cmder) (string, string) {
+	const numCmdLimit = 100
+	const numNameLimit = 10
+
+	seen := make(map[string]struct{}, numNameLimit)
+	unqNames := make([]string, 0, numNameLimit)
+
+	b := make([]byte, 0, 32*len(cmds))
+
+	for i, cmd := range cmds {
+		if i > numCmdLimit {
+			break
+		}
+
+		if i > 0 {
+			b = append(b, '\n')
+		}
+		b = AppendCmd(b, cmd)
+
+		if len(unqNames) >= numNameLimit {
+			continue
+		}
+
+		name := cmd.FullName()
+		if _, ok := seen[name]; !ok {
+			seen[name] = struct{}{}
+			unqNames = append(unqNames, name)
+		}
+	}
+
+	summary := strings.Join(unqNames, " ")
+	return summary, String(b)
+}
+
+func AppendCmd(b []byte, cmd redis.Cmder) []byte {
+	const numArgLimit = 32
+
+	for i, arg := range cmd.Args() {
+		if i > numArgLimit {
+			break
+		}
+		if i > 0 {
+			b = append(b, ' ')
+		}
+		b = appendArg(b, arg)
+	}
+
+	if err := cmd.Err(); err != nil {
+		b = append(b, ": "...)
+		b = append(b, err.Error()...)
+	}
+
+	return b
+}
+
+func appendArg(b []byte, v interface{}) []byte {
+	const argLenLimit = 64
+
+	switch v := v.(type) {
+	case nil:
+		return append(b, "<nil>"...)
+	case string:
+		if len(v) > argLenLimit {
+			v = v[:argLenLimit]
+		}
+		return appendUTF8String(b, Bytes(v))
+	case []byte:
+		if len(v) > argLenLimit {
+			v = v[:argLenLimit]
+		}
+		return appendUTF8String(b, v)
+	case int:
+		return strconv.AppendInt(b, int64(v), 10)
+	case int8:
+		return strconv.AppendInt(b, int64(v), 10)
+	case int16:
+		return strconv.AppendInt(b, int64(v), 10)
+	case int32:
+		return strconv.AppendInt(b, int64(v), 10)
+	case int64:
+		return strconv.AppendInt(b, v, 10)
+	case uint:
+		return strconv.AppendUint(b, uint64(v), 10)
+	case uint8:
+		return strconv.AppendUint(b, uint64(v), 10)
+	case uint16:
+		return strconv.AppendUint(b, uint64(v), 10)
+	case uint32:
+		return strconv.AppendUint(b, uint64(v), 10)
+	case uint64:
+		return strconv.AppendUint(b, v, 10)
+	case float32:
+		return strconv.AppendFloat(b, float64(v), 'f', -1, 64)
+	case float64:
+		return strconv.AppendFloat(b, v, 'f', -1, 64)
+	case bool:
+		if v {
+			return append(b, "true"...)
+		}
+		return append(b, "false"...)
+	case time.Time:
+		return v.AppendFormat(b, time.RFC3339Nano)
+	default:
+		return append(b, fmt.Sprint(v)...)
+	}
+}
+
+func appendUTF8String(dst []byte, src []byte) []byte {
+	if isSimple(src) {
+		dst = append(dst, src...)
+		return dst
+	}
+
+	s := len(dst)
+	dst = append(dst, make([]byte, hex.EncodedLen(len(src)))...)
+	hex.Encode(dst[s:], src)
+	return dst
+}
+
+func isSimple(b []byte) bool {
+	for _, c := range b {
+		if !isSimpleByte(c) {
+			return false
+		}
+	}
+	return true
+}
+
+func isSimpleByte(c byte) bool {
+	return c >= 0x21 && c <= 0x7e
+}

extra/rediscmd/rediscmd_test.go

@@ -0,0 +1,32 @@
+package rediscmd
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/ginkgo/extensions/table"
+	. "github.com/onsi/gomega"
+)
+
+func TestGinkgo(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "redisext")
+}
+
+var _ = Describe("AppendArg", func() {
+	DescribeTable("...",
+		func(src string, wanted string) {
+			b := appendArg(nil, src)
+			Expect(string(b)).To(Equal(wanted))
+		},
+
+		Entry("", "-inf", "-inf"),
+		Entry("", "+inf", "+inf"),
+		Entry("", "foo.bar", "foo.bar"),
+		Entry("", "foo:bar", "foo:bar"),
+		Entry("", "foo{bar}", "foo{bar}"),
+		Entry("", "foo-123_BAR", "foo-123_BAR"),
+		Entry("", "foo\nbar", "666f6f0a626172"),
+		Entry("", "\000", "00"),
+	)
+})

extra/rediscmd/safe.go

@@ -0,0 +1,11 @@
+// +build appengine
+
+package rediscmd
+
+func String(b []byte) string {
+	return string(b)
+}
+
+func Bytes(s string) []byte {
+	return []byte(s)
+}

extra/rediscmd/unsafe.go

@@ -0,0 +1,20 @@
+// +build !appengine
+
+package rediscmd
+
+import "unsafe"
+
+// String converts byte slice to string.
+func String(b []byte) string {
+	return *(*string)(unsafe.Pointer(&b))
+}
+
+// Bytes converts string to byte slice.
+func Bytes(s string) []byte {
+	return *(*[]byte)(unsafe.Pointer(
+		&struct {
+			string
+			Cap int
+		}{s, len(s)},
+	))
+}

extra/redisotel/go.mod

@@ -0,0 +1,11 @@
+module github.com/go-redis/redis/extra/redisotel
+
+go 1.15
+
+replace github.com/go-redis/redis/extra/rediscmd => ../rediscmd
+
+require (
+	github.com/go-redis/redis/extra/rediscmd v0.1.0
+	github.com/go-redis/redis/v8 v8.3.2
+	go.opentelemetry.io/otel v0.13.0
+)