added graceful error handling if bird is unreachable

VERSION

@@ -1 +1 @@
-1.8.1
+1.8.5

bird/bird.go

@@ -1,10 +1,12 @@
 package bird
 
 import (
-	"os/exec"
+	"reflect"
 	"strings"
 	"sync"
 	"time"
+
+	"os/exec"
 )
 
 var ClientConf BirdConfig
@@ -19,17 +21,24 @@ var Cache = struct {
 	m map[string]Parsed
 }{m: make(map[string]Parsed)}
 
+var NilParse Parsed = (Parsed)(nil)
+var BirdError Parsed = Parsed{"error": "bird unreachable"}
+
+func isSpecial(ret Parsed) bool {
+	return reflect.DeepEqual(ret, NilParse) || reflect.DeepEqual(ret, BirdError)
+}
+
 func fromCache(key string) (Parsed, bool) {
 	Cache.RLock()
 	val, ok := Cache.m[key]
 	Cache.RUnlock()
 	if !ok {
-		return nil, false
+		return NilParse, false
 	}
 
 	ttl, correct := val["ttl"].(time.Time)
 	if !correct || ttl.Before(time.Now()) {
-		return nil, false
+		return NilParse, false
 	}
 
 	return val, ok
@@ -88,14 +97,14 @@ func RunAndParse(cmd string, parser func([]byte) Parsed) (Parsed, bool) {
 	}
 
 	if !checkRateLimit() {
-		return nil, false
+		return NilParse, false
 	}
 
 	out, err := Run(cmd)
 
 	if err != nil {
 		// ignore errors for now
-		return Parsed{}, false
+		return BirdError, false
 	}
 
 	parsed := parser(out)
@@ -105,7 +114,7 @@ func RunAndParse(cmd string, parser func([]byte) Parsed) (Parsed, bool) {
 
 func Status() (Parsed, bool) {
 	birdStatus, ok := RunAndParse("status", parseStatus)
-	if birdStatus == nil {
+	if isSpecial(birdStatus) {
 		return birdStatus, ok
 	}
 	status := birdStatus["status"].(Parsed)
@@ -145,7 +154,7 @@ func Protocols() (Parsed, bool) {
 
 func ProtocolsBgp() (Parsed, bool) {
 	p, from_cache := Protocols()
-	if p == nil {
+	if isSpecial(p) {
 		return p, from_cache
 	}
 	protocols := p["protocols"].([]string)

birdwatcher.go

@@ -13,7 +13,7 @@ import (
 )
 
 //go:generate versionize
-var VERSION = "1.7.18"
+var VERSION = "1.8.5"
 
 func isModuleEnabled(module string, modulesEnabled []string) bool {
 	for _, enabled := range modulesEnabled {

endpoints/endpoint.go

@@ -3,6 +3,7 @@ package endpoints
 import (
 	"fmt"
 	"log"
+	"reflect"
 	"strings"
 
 	"compress/gzip"
@@ -55,10 +56,17 @@ func Endpoint(wrapped endpoint) httprouter.Handle {
 		res := make(map[string]interface{})
 
 		ret, from_cache := wrapped(r, ps)
-		if ret == nil {
+		if reflect.DeepEqual(ret, bird.NilParse) {
 			w.WriteHeader(http.StatusTooManyRequests)
 			return
 		}
+		if reflect.DeepEqual(ret, bird.BirdError) {
+			w.WriteHeader(http.StatusInternalServerError)
+			w.Header().Set("Content-Type", "application/json")
+			js, _ := json.Marshal(ret)
+			w.Write(js)
+			return
+		}
 		res["api"] = GetApiInfo(from_cache)
 
 		for k, v := range ret {