Create request_id directive #1590 (#1711)

* Create request_id directive #1590

* Address Comments

* Fix TestListenerAddrEqual

* requestid: Add some tests

* Address Comments by tobya

* Address Comments

caddyhttp/caddyhttp.go

@@ -24,6 +24,7 @@ import (
 	_ "github.com/mholt/caddy/caddyhttp/proxy"
 	_ "github.com/mholt/caddy/caddyhttp/push"
 	_ "github.com/mholt/caddy/caddyhttp/redirect"
+	_ "github.com/mholt/caddy/caddyhttp/requestid"
 	_ "github.com/mholt/caddy/caddyhttp/rewrite"
 	_ "github.com/mholt/caddy/caddyhttp/root"
 	_ "github.com/mholt/caddy/caddyhttp/status"

caddyhttp/caddyhttp_test.go

@@ -11,7 +11,7 @@ import (
 // ensure that the standard plugins are in fact plugged in
 // and registered properly; this is a quick/naive way to do it.
 func TestStandardPlugins(t *testing.T) {
-	numStandardPlugins := 31 // importing caddyhttp plugs in this many plugins
+	numStandardPlugins := 32 // importing caddyhttp plugs in this many plugins
 	s := caddy.DescribePlugins()
 	if got, want := strings.Count(s, "\n"), numStandardPlugins+5; got != want {
 		t.Errorf("Expected all standard plugins to be plugged in, got:\n%s", s)

caddyhttp/httpserver/middleware.go

@@ -205,4 +205,7 @@ const (
 
 	// MitmCtxKey is the key for the result of MITM detection
 	MitmCtxKey caddy.CtxKey = "mitm"
+
+	// RequestIDCtxKey is the key for the U4 UUID value
+	RequestIDCtxKey caddy.CtxKey = "request_id"
 )

caddyhttp/httpserver/plugin.go

@@ -443,6 +443,7 @@ var directives = []string{
 	// services/utilities, or other directives that don't necessarily inject handlers
 	"startup",
 	"shutdown",
+	"requestid",
 	"realip", // github.com/captncraig/caddy-realip
 	"git",    // github.com/abiosoft/caddy-git
 

caddyhttp/httpserver/replacer.go

@@ -243,6 +243,9 @@ func (r *replacer) getSubstitution(key string) string {
 	case "{path_escaped}":
 		u, _ := r.request.Context().Value(OriginalURLCtxKey).(url.URL)
 		return url.QueryEscape(u.Path)
+	case "{request_id}":
+		reqid, _ := r.request.Context().Value(RequestIDCtxKey).(string)
+		return reqid
 	case "{rewrite_path}":
 		return r.request.URL.Path
 	case "{rewrite_path_escaped}":

caddyhttp/requestid/requestid.go

@@ -0,0 +1,34 @@
+package requestid
+
+import (
+	"context"
+	"log"
+	"net/http"
+
+	"github.com/mholt/caddy/caddyhttp/httpserver"
+	uuid "github.com/nu7hatch/gouuid"
+)
+
+// Handler is a middleware handler
+type Handler struct {
+	Next httpserver.Handler
+}
+
+func (h Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) (int, error) {
+	reqid := UUID()
+	c := context.WithValue(r.Context(), httpserver.RequestIDCtxKey, reqid)
+	r = r.WithContext(c)
+
+	return h.Next.ServeHTTP(w, r)
+}
+
+// UUID returns U4 UUID
+func UUID() string {
+	u4, err := uuid.NewV4()
+	if err != nil {
+		log.Printf("[ERROR] generating request ID: %v", err)
+		return ""
+	}
+
+	return u4.String()
+}

caddyhttp/requestid/requestid_test.go

@@ -0,0 +1,33 @@
+package requestid
+
+import (
+	"context"
+	"net/http"
+	"testing"
+
+	"github.com/mholt/caddy/caddyhttp/httpserver"
+)
+
+func TestRequestID(t *testing.T) {
+	request, err := http.NewRequest("GET", "http://localhost/", nil)
+	if err != nil {
+		t.Fatal("Could not create HTTP request:", err)
+	}
+
+	reqid := UUID()
+
+	c := context.WithValue(request.Context(), httpserver.RequestIDCtxKey, reqid)
+
+	request = request.WithContext(c)
+
+	// See caddyhttp/replacer.go
+	value, _ := request.Context().Value(httpserver.RequestIDCtxKey).(string)
+
+	if value == "" {
+		t.Fatal("Request ID should not be empty")
+	}
+
+	if value != reqid {
+		t.Fatal("Request ID does not match")
+	}
+}

caddyhttp/requestid/setup.go

@@ -0,0 +1,27 @@
+package requestid
+
+import (
+	"github.com/mholt/caddy"
+	"github.com/mholt/caddy/caddyhttp/httpserver"
+)
+
+func init() {
+	caddy.RegisterPlugin("requestid", caddy.Plugin{
+		ServerType: "http",
+		Action:     setup,
+	})
+}
+
+func setup(c *caddy.Controller) error {
+	for c.Next() {
+		if c.NextArg() {
+			return c.ArgErr() //no arg expected.
+		}
+	}
+
+	httpserver.GetConfig(c).AddMiddleware(func(next httpserver.Handler) httpserver.Handler {
+		return Handler{Next: next}
+	})
+
+	return nil
+}

caddyhttp/requestid/setup_test.go

@@ -0,0 +1,43 @@
+package requestid
+
+import (
+	"testing"
+
+	"github.com/mholt/caddy"
+	"github.com/mholt/caddy/caddyhttp/httpserver"
+)
+
+func TestSetup(t *testing.T) {
+	c := caddy.NewTestController("http", `requestid`)
+	err := setup(c)
+	if err != nil {
+		t.Errorf("Expected no errors, got: %v", err)
+	}
+	mids := httpserver.GetConfig(c).Middleware()
+	if len(mids) == 0 {
+		t.Fatal("Expected middleware, got 0 instead")
+	}
+
+	handler := mids[0](httpserver.EmptyNext)
+	myHandler, ok := handler.(Handler)
+
+	if !ok {
+		t.Fatalf("Expected handler to be type Handler, got: %#v", handler)
+	}
+
+	if !httpserver.SameNext(myHandler.Next, httpserver.EmptyNext) {
+		t.Error("'Next' field of handler was not set properly")
+	}
+}
+
+func TestSetupWithArg(t *testing.T) {
+	c := caddy.NewTestController("http", `requestid abc`)
+	err := setup(c)
+	if err == nil {
+		t.Errorf("Expected an error, got: %v", err)
+	}
+	mids := httpserver.GetConfig(c).Middleware()
+	if len(mids) != 0 {
+		t.Fatal("Expected no middleware")
+	}
+}

vendor/github.com/nu7hatch/gouuid/COPYING

@@ -0,0 +1,19 @@
+Copyright (C) 2011 by Krzysztof Kowalik <chris@nu7hat.ch>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

vendor/github.com/nu7hatch/gouuid/uuid.go

@@ -0,0 +1,173 @@
+// This package provides immutable UUID structs and the functions
+// NewV3, NewV4, NewV5 and Parse() for generating versions 3, 4
+// and 5 UUIDs as specified in RFC 4122.
+//
+// Copyright (C) 2011 by Krzysztof Kowalik <chris@nu7hat.ch>
+package uuid
+
+import (
+	"crypto/md5"
+	"crypto/rand"
+	"crypto/sha1"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"hash"
+	"regexp"
+)
+
+// The UUID reserved variants. 
+const (
+	ReservedNCS       byte = 0x80
+	ReservedRFC4122   byte = 0x40
+	ReservedMicrosoft byte = 0x20
+	ReservedFuture    byte = 0x00
+)
+
+// The following standard UUIDs are for use with NewV3() or NewV5().
+var (
+	NamespaceDNS, _  = ParseHex("6ba7b810-9dad-11d1-80b4-00c04fd430c8")
+	NamespaceURL, _  = ParseHex("6ba7b811-9dad-11d1-80b4-00c04fd430c8")
+	NamespaceOID, _  = ParseHex("6ba7b812-9dad-11d1-80b4-00c04fd430c8")
+	NamespaceX500, _ = ParseHex("6ba7b814-9dad-11d1-80b4-00c04fd430c8")
+)
+
+// Pattern used to parse hex string representation of the UUID.
+// FIXME: do something to consider both brackets at one time,
+// current one allows to parse string with only one opening
+// or closing bracket.
+const hexPattern = "^(urn\\:uuid\\:)?\\{?([a-z0-9]{8})-([a-z0-9]{4})-" +
+	"([1-5][a-z0-9]{3})-([a-z0-9]{4})-([a-z0-9]{12})\\}?$"
+
+var re = regexp.MustCompile(hexPattern)
+
+// A UUID representation compliant with specification in
+// RFC 4122 document.
+type UUID [16]byte
+
+// ParseHex creates a UUID object from given hex string
+// representation. Function accepts UUID string in following
+// formats:
+//
+//     uuid.ParseHex("6ba7b814-9dad-11d1-80b4-00c04fd430c8")
+//     uuid.ParseHex("{6ba7b814-9dad-11d1-80b4-00c04fd430c8}")
+//     uuid.ParseHex("urn:uuid:6ba7b814-9dad-11d1-80b4-00c04fd430c8")
+//
+func ParseHex(s string) (u *UUID, err error) {
+	md := re.FindStringSubmatch(s)
+	if md == nil {
+		err = errors.New("Invalid UUID string")
+		return
+	}
+	hash := md[2] + md[3] + md[4] + md[5] + md[6]
+	b, err := hex.DecodeString(hash)
+	if err != nil {
+		return
+	}
+	u = new(UUID)
+	copy(u[:], b)
+	return
+}
+
+// Parse creates a UUID object from given bytes slice.
+func Parse(b []byte) (u *UUID, err error) {
+	if len(b) != 16 {
+		err = errors.New("Given slice is not valid UUID sequence")
+		return
+	}
+	u = new(UUID)
+	copy(u[:], b)
+	return
+}
+
+// Generate a UUID based on the MD5 hash of a namespace identifier
+// and a name.
+func NewV3(ns *UUID, name []byte) (u *UUID, err error) {
+	if ns == nil {
+		err = errors.New("Invalid namespace UUID")
+		return
+	}
+	u = new(UUID)
+	// Set all bits to MD5 hash generated from namespace and name.
+	u.setBytesFromHash(md5.New(), ns[:], name)
+	u.setVariant(ReservedRFC4122)
+	u.setVersion(3)
+	return
+}
+
+// Generate a random UUID.
+func NewV4() (u *UUID, err error) {
+	u = new(UUID)
+	// Set all bits to randomly (or pseudo-randomly) chosen values.
+	_, err = rand.Read(u[:])
+	if err != nil {
+		return
+	}
+	u.setVariant(ReservedRFC4122)
+	u.setVersion(4)
+	return
+}
+
+// Generate a UUID based on the SHA-1 hash of a namespace identifier
+// and a name.
+func NewV5(ns *UUID, name []byte) (u *UUID, err error) {
+	u = new(UUID)
+	// Set all bits to truncated SHA1 hash generated from namespace
+	// and name.
+	u.setBytesFromHash(sha1.New(), ns[:], name)
+	u.setVariant(ReservedRFC4122)
+	u.setVersion(5)
+	return
+}
+
+// Generate a MD5 hash of a namespace and a name, and copy it to the
+// UUID slice.
+func (u *UUID) setBytesFromHash(hash hash.Hash, ns, name []byte) {
+	hash.Write(ns[:])
+	hash.Write(name)
+	copy(u[:], hash.Sum([]byte{})[:16])
+}
+
+// Set the two most significant bits (bits 6 and 7) of the
+// clock_seq_hi_and_reserved to zero and one, respectively.
+func (u *UUID) setVariant(v byte) {
+	switch v {
+	case ReservedNCS:
+		u[8] = (u[8] | ReservedNCS) & 0xBF
+	case ReservedRFC4122:
+		u[8] = (u[8] | ReservedRFC4122) & 0x7F
+	case ReservedMicrosoft:
+		u[8] = (u[8] | ReservedMicrosoft) & 0x3F
+	}
+}
+
+// Variant returns the UUID Variant, which determines the internal
+// layout of the UUID. This will be one of the constants: RESERVED_NCS,
+// RFC_4122, RESERVED_MICROSOFT, RESERVED_FUTURE.
+func (u *UUID) Variant() byte {
+	if u[8]&ReservedNCS == ReservedNCS {
+		return ReservedNCS
+	} else if u[8]&ReservedRFC4122 == ReservedRFC4122 {
+		return ReservedRFC4122
+	} else if u[8]&ReservedMicrosoft == ReservedMicrosoft {
+		return ReservedMicrosoft
+	}
+	return ReservedFuture
+}
+
+// Set the four most significant bits (bits 12 through 15) of the
+// time_hi_and_version field to the 4-bit version number.
+func (u *UUID) setVersion(v byte) {
+	u[6] = (u[6] & 0xF) | (v << 4)
+}
+
+// Version returns a version number of the algorithm used to
+// generate the UUID sequence.
+func (u *UUID) Version() uint {
+	return uint(u[6] >> 4)
+}
+
+// Returns unparsed version of the generated UUID sequence.
+func (u *UUID) String() string {
+	return fmt.Sprintf("%x-%x-%x-%x-%x", u[0:4], u[4:6], u[6:8], u[8:10], u[10:])
+}

vendor/manifest

@@ -165,6 +165,14 @@
 			"branch": "master",
 			"notests": true
 		},
+		{
+			"importpath": "github.com/nu7hatch/gouuid",
+			"repository": "https://github.com/nu7hatch/gouuid",
+			"vcs": "git",
+			"revision": "179d4d0c4d8d407a32af483c2354df1d2c91e6c3",
+			"branch": "master",
+			"notests": true
+		},
 		{
 			"importpath": "github.com/russross/blackfriday",
 			"repository": "https://github.com/russross/blackfriday",