feat: automatically set GOMEMLIMIT (#1010)

Author: dunglas

caddy/go.mod

@@ -12,11 +12,13 @@ retract (
 replace github.com/dunglas/mercure => ../
 
 require (
+	github.com/KimMachineGun/automemlimit v0.7.0
 	github.com/MicahParks/keyfunc/v3 v3.3.10
 	github.com/caddyserver/caddy/v2 v2.9.1
 	github.com/dunglas/mercure v0.18.2
 	github.com/stretchr/testify v1.10.0
 	go.uber.org/zap v1.27.0
+	go.uber.org/zap/exp v0.3.0
 )
 
 require (
@@ -102,6 +104,7 @@ require (
 	github.com/mschoch/smat v0.2.0 // indirect
 	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
 	github.com/onsi/ginkgo/v2 v2.22.2 // indirect
+	github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58 // indirect
 	github.com/pelletier/go-toml/v2 v2.2.3 // indirect
 	github.com/pires/go-proxyproto v0.8.0 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
@@ -162,7 +165,6 @@ require (
 	go.uber.org/automaxprocs v1.6.0 // indirect
 	go.uber.org/mock v0.5.0 // indirect
 	go.uber.org/multierr v1.11.0 // indirect
-	go.uber.org/zap/exp v0.3.0 // indirect
 	golang.org/x/crypto v0.33.0 // indirect
 	golang.org/x/crypto/x509roots/fallback v0.0.0-20250214233241-911360c8a4f4 // indirect
 	golang.org/x/exp v0.0.0-20250215185904-eff6e970281f // indirect

caddy/go.sum

@@ -33,6 +33,8 @@ github.com/AndreasBriese/bbloom v0.0.0-20190825152654-46b345b51c96/go.mod h1:bOv
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/BurntSushi/toml v1.4.0 h1:kuoIxZQy2WRRk1pttg9asf+WVv6tWQuBNVmK8+nqPr0=
 github.com/BurntSushi/toml v1.4.0/go.mod h1:ukJfTF/6rtPPRCnwkur4qwRxa8vTRFBF0uk2lLoLwho=
+github.com/KimMachineGun/automemlimit v0.7.0 h1:7G06p/dMSf7G8E6oq+f2uOPuVncFyIlDI/pBWK49u88=
+github.com/KimMachineGun/automemlimit v0.7.0/go.mod h1:QZxpHaGOQoYvFhv/r4u3U0JTC2ZcOwbSr11UZF46UBM=
 github.com/Masterminds/goutils v1.1.1 h1:5nUrii3FMTL5diU80unEVvNevw1nH4+ZV4DSLVJLSYI=
 github.com/Masterminds/goutils v1.1.1/go.mod h1:8cTjp+g8YejhMuvIA5y2vz3BpJxksy863GQaJW2MFNU=
 github.com/Masterminds/semver/v3 v3.3.1 h1:QtNSWtVZ3nBfk8mAOu/B6v7FMJ+NHTIgUPi7rj+4nv4=
@@ -336,6 +338,8 @@ github.com/onsi/ginkgo/v2 v2.22.2/go.mod h1:oeMosUL+8LtarXBHu/c0bx2D/K9zyQ6uX3cT
 github.com/onsi/gomega v1.36.2 h1:koNYke6TVk6ZmnyHrCXba/T/MoLBXFjeC1PtvYgw0A8=
 github.com/onsi/gomega v1.36.2/go.mod h1:DdwyADRjrc825LhMEkD76cHR5+pUnjhUN8GlHlRPHzY=
 github.com/openzipkin/zipkin-go v0.1.1/go.mod h1:NtoC/o8u3JlF1lSlyPNswIbeQH9bJTmOf0Erfk+hxe8=
+github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58 h1:onHthvaw9LFnH4t2DcNVpwGmV9E1BkGknEliJkfwQj0=
+github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58/go.mod h1:DXv8WO4yhMYhSNPKjeNKa5WY9YCIEBRbNzFFPJbWO6Y=
 github.com/pelletier/go-toml v1.2.0/go.mod h1:5z9KED0ma1S8pY6P1sdut58dfprrGBbd/94hg7ilaic=
 github.com/pelletier/go-toml/v2 v2.2.3 h1:YmeHyLY8mFWbdkNWwpr+qIL2bEqT0o95WSdkNHvL12M=
 github.com/pelletier/go-toml/v2 v2.2.3/go.mod h1:MfCQTFTvCcUyyvvwm1+G6H/jORL20Xlb6rzQu9GuUkc=

caddy/mercure/main.go

@@ -2,13 +2,33 @@
 package main
 
 import (
+	"log/slog"
+
+	"github.com/caddyserver/caddy/v2"
+
+	"github.com/KimMachineGun/automemlimit/memlimit"
 	caddycmd "github.com/caddyserver/caddy/v2/cmd"
+	"go.uber.org/zap/exp/zapslog"
 
 	// plug in Caddy modules here.
 	_ "github.com/caddyserver/caddy/v2/modules/standard"
 	_ "github.com/dunglas/mercure/caddy"
 )
 
 func main() {
+	// Backport of https://github.com/caddyserver/caddy/pull/6809
+	// TODO: remove this block when Caddy 2.10 will be released
+	_, _ = memlimit.SetGoMemLimitWithOpts(
+		memlimit.WithLogger(
+			slog.New(zapslog.NewHandler(caddy.Log().Core())),
+		),
+		memlimit.WithProvider(
+			memlimit.ApplyFallback(
+				memlimit.FromCgroup,
+				memlimit.FromSystem,
+			),
+		),
+	)
+
 	caddycmd.Main()
 }