add a recoverer middleware

_examples/basic/go.mod

@@ -4,15 +4,21 @@ go 1.18
 
 replace github.com/goware/alerter => ../../
 
-require github.com/goware/alerter v0.0.0-00010101000000-000000000000
+require (
+	github.com/go-chi/chi/v5 v5.0.10
+	github.com/goware/alerter v0.0.0-00010101000000-000000000000
+)
 
 require (
-	github.com/goware/cachestore v0.3.1 // indirect
-	github.com/hashicorp/golang-lru v0.5.4 // indirect
-	github.com/klauspost/cpuid/v2 v2.0.9 // indirect
-	github.com/mattn/go-colorable v0.1.12 // indirect
-	github.com/mattn/go-isatty v0.0.14 // indirect
-	github.com/rs/zerolog v1.28.0 // indirect
+	github.com/cespare/xxhash/v2 v2.2.0 // indirect
+	github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f // indirect
+	github.com/goware/cachestore v0.7.0 // indirect
+	github.com/hashicorp/golang-lru/v2 v2.0.1 // indirect
+	github.com/klauspost/cpuid/v2 v2.2.5 // indirect
+	github.com/mattn/go-colorable v0.1.13 // indirect
+	github.com/mattn/go-isatty v0.0.19 // indirect
+	github.com/redis/go-redis/v9 v9.0.3 // indirect
+	github.com/rs/zerolog v1.29.1 // indirect
 	github.com/zeebo/xxh3 v1.0.2 // indirect
-	golang.org/x/sys v0.0.0-20210927094055-39ccf1dd6fa6 // indirect
+	golang.org/x/sys v0.10.0 // indirect
 )

_examples/basic/go.sum

@@ -1,26 +1,43 @@
-github.com/coreos/go-systemd/v22 v22.3.3-0.20220203105225-a9a7ef127534/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
-github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/bsm/ginkgo/v2 v2.7.0 h1:ItPMPH90RbmZJt5GtkcNvIRuGEdwlBItdNVoyzaNQao=
+github.com/bsm/gomega v1.26.0 h1:LhQm+AFcgV2M0WyKroMASzAzCAJVpAxQXv4SaI9a69Y=
+github.com/cespare/xxhash/v2 v2.2.0 h1:DC2CZ1Ep5Y4k3ZQ899DldepgrayRUGE6BBZ/cd9Cj44=
+github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
+github.com/coreos/go-systemd/v22 v22.5.0/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f h1:lO4WD4F/rVNCu3HqELle0jiPLLBs70cWOduZpkS1E78=
+github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f/go.mod h1:cuUVRXasLTGF7a8hSLbxyZXjz+1KgoB3wDUb6vlszIc=
+github.com/go-chi/chi/v5 v5.0.10 h1:rLz5avzKpjqxrYwXNfmjkrYYXOyLJd37pz53UFHC6vk=
+github.com/go-chi/chi/v5 v5.0.10/go.mod h1:DslCQbL2OYiznFReuXYUmQ2hGd1aDpCnlMNITLSKoi8=
 github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
-github.com/goware/cachestore v0.3.1 h1:c17LIMGVM/Y4HBzLIHNuR3FFkySYr3eVoYgT53U4Fl4=
-github.com/goware/cachestore v0.3.1/go.mod h1:ifyKCgoWJDpJneKC8YUryjgiRy7JnEgbkpe/FpgR6BA=
-github.com/hashicorp/golang-lru v0.5.4 h1:YDjusn29QI/Das2iO9M0BHnIbxPeyuCHsjMW+lJfyTc=
-github.com/hashicorp/golang-lru v0.5.4/go.mod h1:iADmTwqILo4mZ8BN3D2Q6+9jd8WM5uGBxy+E8yxSoD4=
-github.com/klauspost/cpuid/v2 v2.0.9 h1:lgaqFMSdTdQYdZ04uHyN2d/eKdOMyi2YLSvlQIBFYa4=
-github.com/klauspost/cpuid/v2 v2.0.9/go.mod h1:FInQzS24/EEf25PyTYn52gqo7WaD8xa0213Md/qVLRg=
-github.com/mattn/go-colorable v0.1.12 h1:jF+Du6AlPIjs2BiUiQlKOX0rt3SujHxPnksPKZbaA40=
+github.com/goware/cachestore v0.7.0 h1:9aLkGOA0qNaXzXFHP6OzIpmdtkunp0WROTn8XD23RPk=
+github.com/goware/cachestore v0.7.0/go.mod h1:/AoSqLZfLN1nowTOnk4ButuUiDsXC0/Jfjpe/sPX7lE=
+github.com/hashicorp/golang-lru/v2 v2.0.1 h1:5pv5N1lT1fjLg2VQ5KWc7kmucp2x/kvFOnxuVTqZ6x4=
+github.com/hashicorp/golang-lru/v2 v2.0.1/go.mod h1:QeFd9opnmA6QUJc5vARoKUSoFhyfM2/ZepoAG6RGpeM=
+github.com/klauspost/cpuid/v2 v2.2.5 h1:0E5MSMDEoAulmXNFquVs//DdoomxaoTY1kUhbc/qbZg=
+github.com/klauspost/cpuid/v2 v2.2.5/go.mod h1:Lcz8mBdAVJIBVzewtcLocK12l3Y+JytZYpaMropDUws=
 github.com/mattn/go-colorable v0.1.12/go.mod h1:u5H1YNBxpqRaxsYJYSkiCWKzEfiAb1Gb520KVy5xxl4=
-github.com/mattn/go-isatty v0.0.14 h1:yVuAays6BHfxijgZPzw+3Zlu5yQgKGP2/hcQbHb7S9Y=
+github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
+github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
 github.com/mattn/go-isatty v0.0.14/go.mod h1:7GGIvUiUoEMVVmxf/4nioHXj79iQHKdU27kJ6hsGG94=
+github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
+github.com/mattn/go-isatty v0.0.19 h1:JITubQf0MOLdlGRuRq+jtsDlekdYPia9ZFsB8h/APPA=
+github.com/mattn/go-isatty v0.0.19/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/redis/go-redis/v9 v9.0.3 h1:+7mmR26M0IvyLxGZUHxu4GiBkJkVDid0Un+j4ScYu4k=
+github.com/redis/go-redis/v9 v9.0.3/go.mod h1:WqMKv5vnQbRuZstUwxQI195wHy+t4PuXDOjzMvcuQHk=
 github.com/rs/xid v1.4.0/go.mod h1:trrq9SKmegXys3aeAKXMUTdJsYXVwGY3RLcfgqegfbg=
-github.com/rs/zerolog v1.28.0 h1:MirSo27VyNi7RJYP3078AA1+Cyzd2GB66qy3aUHvsWY=
-github.com/rs/zerolog v1.28.0/go.mod h1:NILgTygv/Uej1ra5XxGf82ZFSLk58MFGAUS2o6usyD0=
-github.com/stretchr/testify v1.7.1 h1:5TQK59W5E3v0r2duFAb7P95B6hEeOyEnHRa8MjYSMTY=
+github.com/rs/zerolog v1.29.1 h1:cO+d60CHkknCbvzEWxP0S9K6KqyTjrCNUy1LdQLCGPc=
+github.com/rs/zerolog v1.29.1/go.mod h1:Le6ESbR7hc+DP6Lt1THiV8CQSdkkNrd3R0XbEgp3ZBU=
+github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
 github.com/zeebo/assert v1.3.0 h1:g7C04CbJuIDKNPFHmsk4hwZDO5O+kntRxzaUoNXj+IQ=
 github.com/zeebo/xxh3 v1.0.2 h1:xZmwmqxHZA8AI603jOQ0tMqmBr9lPeFwGg6d+xy9DC0=
 github.com/zeebo/xxh3 v1.0.2/go.mod h1:5NWz9Sef7zIDm2JHfFlcQvNekmcEl9ekUZQQKCYaDcA=
 golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20210927094055-39ccf1dd6fa6 h1:foEbQz/B0Oz6YIqu/69kfXPYeFQAuuMYFkjaqXzl5Wo=
 golang.org/x/sys v0.0.0-20210927094055-39ccf1dd6fa6/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
+golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.10.0 h1:SqMFp9UcQJZa+pmYuAKjd9xq1f0j5rLcDIk0mj4qAsA=
+golang.org/x/sys v0.10.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=

_examples/basic/main.go

@@ -2,7 +2,9 @@ package main
 
 import (
 	"context"
+	"net/http"
 
+	"github.com/go-chi/chi/v5"
 	"github.com/goware/alerter"
 )
 
@@ -11,10 +13,24 @@ func main() {
 		WebhookURL: "https://discord.com/api/webhooks/0000000000/abcdefghijklmnopqrstuvwxyz",
 		// Username:   "Alerter",
 		// AvatarURL:    "https://cdn.discordapp.com/embed/avatars/0.png",
-		RoleIDToPing: 849690281536389230,
+		MentionRoleID: 849690281536389230,
+		Env:           "production",
 	})
 	if err != nil {
 		panic(err)
 	}
-	alerter.Alert(context.Background(), "hello world %v", "error 1 2 3")
+	a.Alert(context.Background(), "hello world %v", "error 1 2 3")
+
+	r := chi.NewRouter()
+	r.Use(a.Recoverer())
+
+	r.Get("/", func(w http.ResponseWriter, r *http.Request) {
+		w.Write([]byte("hello world"))
+	})
+
+	r.Get("/panic", func(w http.ResponseWriter, r *http.Request) {
+		panic("oh no")
+	})
+
+	http.ListenAndServe(":5555", r)
 }

alerter.go

@@ -1,7 +1,11 @@
 package alerter
 
-import "context"
+import (
+	"context"
+	"net/http"
+)
 
 type Alerter interface {
 	Alert(ctx context.Context, format string, v ...interface{})
+	Recoverer() func(next http.Handler) http.Handler
 }

default_alerter.go

@@ -2,7 +2,9 @@ package alerter
 
 import (
 	"context"
+	"net/http"
 
+	"github.com/go-chi/chi/v5/middleware"
 	"github.com/rs/zerolog/log"
 )
 
@@ -22,3 +24,7 @@ func (a *defaultAlerter) Alert(ctx context.Context, format string, v ...interfac
 		log.Error().Str("alert", "alert").Msgf(format, v...)
 	}
 }
+
+func (a *defaultAlerter) Recoverer() func(next http.Handler) http.Handler {
+	return middleware.Recoverer
+}

discord_alerter.go

@@ -154,14 +154,21 @@ func (a *discordAlerter) doRequest(ctx context.Context, cacheKey string, payload
 	}
 }
 
+type field struct {
+	Name   string `json:"name"`
+	Value  string `json:"value"`
+	Inline bool   `json:"inline"`
+}
+
 type embed struct {
 	Author struct {
 		Name    string `json:"name"`
 		IconURL string `json:"icon_url"`
 	}
-	Title       string `json:"title"`
-	Description string `json:"description"`
-	Color       int    `json:"color"`
+	Title       string  `json:"title"`
+	Description string  `json:"description"`
+	Color       int     `json:"color"`
+	Fields      []field `json:"fields"`
 }
 
 type payload struct {

go.mod

@@ -3,6 +3,7 @@ module github.com/goware/alerter
 go 1.18
 
 require (
+	github.com/go-chi/chi/v5 v5.0.10
 	github.com/goware/cachestore v0.7.0
 	github.com/rs/zerolog v1.29.1
 	github.com/zeebo/xxh3 v1.0.2

go.sum

@@ -6,6 +6,8 @@ github.com/coreos/go-systemd/v22 v22.5.0/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSV
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f h1:lO4WD4F/rVNCu3HqELle0jiPLLBs70cWOduZpkS1E78=
 github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f/go.mod h1:cuUVRXasLTGF7a8hSLbxyZXjz+1KgoB3wDUb6vlszIc=
+github.com/go-chi/chi/v5 v5.0.10 h1:rLz5avzKpjqxrYwXNfmjkrYYXOyLJd37pz53UFHC6vk=
+github.com/go-chi/chi/v5 v5.0.10/go.mod h1:DslCQbL2OYiznFReuXYUmQ2hGd1aDpCnlMNITLSKoi8=
 github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
 github.com/goware/cachestore v0.7.0 h1:9aLkGOA0qNaXzXFHP6OzIpmdtkunp0WROTn8XD23RPk=
 github.com/goware/cachestore v0.7.0/go.mod h1:/AoSqLZfLN1nowTOnk4ButuUiDsXC0/Jfjpe/sPX7lE=

recoverer.go

@@ -0,0 +1,122 @@
+package alerter
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"runtime/debug"
+	"strings"
+
+	"github.com/go-chi/chi/v5/middleware"
+)
+
+func (a *discordAlerter) Recoverer() func(next http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		fn := func(w http.ResponseWriter, r *http.Request) {
+			defer func() {
+				if rvr := recover(); rvr != nil {
+					if rvr == http.ErrAbortHandler {
+						// we don't recover http.ErrAbortHandler so the response
+						// to the client is aborted, this should not be logged
+						panic(rvr)
+					}
+
+					if !a.SkipLogEntry {
+						middleware.PrintPrettyStack(rvr)
+					}
+
+					p, err := a.alertWithPanicPayload(r, rvr)
+					if err != nil {
+						return
+					}
+					cacheKey := fmt.Sprintf("%d", xxh64FromString(p))
+					a.doRequest(r.Context(), cacheKey, p)
+
+					if r.Header.Get("Connection") != "Upgrade" {
+						w.WriteHeader(http.StatusInternalServerError)
+					}
+				}
+			}()
+
+			next.ServeHTTP(w, r)
+		}
+
+		return http.HandlerFunc(fn)
+	}
+}
+
+// parseStack is a modified version of parse from go-chi/chi/middleware/recoverer.go
+func (a *discordAlerter) parseStack(debugStack []byte, rvr interface{}) (string, error) {
+	var err error
+
+	buf := &bytes.Buffer{}
+
+	fmt.Fprintf(buf, "panic: %v\n", rvr)
+
+	stack := strings.Split(string(debugStack), "\n")
+	lines := []string{}
+
+	// locate panic line, as we may have nested panics
+	for i := len(stack) - 1; i > 0; i-- {
+		lines = append(lines, stack[i])
+		if strings.HasPrefix(stack[i], "panic(") {
+			lines = lines[0 : len(lines)-2] // remove boilerplate
+			break
+		}
+	}
+
+	// reverse
+	for i := len(lines)/2 - 1; i >= 0; i-- {
+		opp := len(lines) - 1 - i
+		lines[i], lines[opp] = lines[opp], lines[i]
+	}
+
+	for _, l := range lines {
+		fmt.Fprintf(buf, "\t %s", l)
+	}
+
+	return buf.String(), err
+}
+
+func (a *discordAlerter) alertWithPanicPayload(r *http.Request, rvr interface{}) (string, error) {
+	debugStack, err := a.parseStack(debug.Stack(), rvr)
+	if err != nil {
+		return "", err
+	}
+
+	p := payload{
+		Username:  a.Username,
+		AvatarURL: a.AvatarURL,
+		Embeds: []embed{
+			{
+				Author: struct {
+					Name    string `json:"name"`
+					IconURL string `json:"icon_url"`
+				}{Name: a.Username, IconURL: a.AvatarURL},
+				Title:       "Panic Stack Trace",
+				Description: fmt.Sprintf("```\n %v \n ```", debugStack),
+				Fields: []field{
+					{
+						Name:  "ENV:",
+						Value: a.Env,
+					},
+					{
+						Name:  "Request",
+						Value: fmt.Sprintf("%s %s", r.Method, r.URL.String()),
+					},
+				},
+				Color: 0xCC0000,
+			},
+		},
+	}
+	if a.MentionRoleID > 0 {
+		p.Content = fmt.Sprintf("<@&%d>", a.MentionRoleID)
+	}
+
+	b, err := json.Marshal(p)
+	if err != nil {
+		return "", err
+	}
+	return string(b), nil
+}