Issue certificates in the image and correct silent mail failures

.env.example

@@ -28,5 +28,5 @@ SENTRY_RELEASE=
 CF_Token=
 CF_Zone_ID=
 DNS_API=dns_cf
-ACME_SH_EMAIL=
+ACME_SH_EMAIL=devnull@localhost
 MXDOMAIN=ineedatest.email

Dockerfile

@@ -1,6 +1,6 @@
 # Build stage
-# Official images publish 1.26.3-alpine / 1.26.3-alpine3.22+ — not alpine3.21.
-FROM golang:1.26.3-alpine AS builder
+# Matches the patch in go.mod. This tag is Alpine 3.24; the runtime stage stays on 3.21.
+FROM golang:1.26.10-alpine AS builder
 
 WORKDIR /app
 
@@ -22,7 +22,7 @@ FROM alpine:3.21
 ARG ACME_SH_VERSION=3.0.7
 
 # Install ca-certificates, openssl, socat, git, bash; pin acme.sh via git tag (no curl|sh)
-RUN apk add --no-cache ca-certificates openssl socat git bash curl \
+RUN apk add --no-cache ca-certificates openssl socat git bash curl su-exec \
  && git clone --depth 1 --branch "${ACME_SH_VERSION}" https://github.com/acmesh-official/acme.sh.git /opt/acme.sh \
  && addgroup -S inboundparse \
  && adduser -S -G inboundparse -h /home/inboundparse inboundparse \
@@ -39,14 +39,15 @@ COPY start.sh /usr/local/bin/start.sh
 RUN chmod +x /usr/local/bin/inboundparse /usr/local/bin/start.sh \
  && chown inboundparse:inboundparse /usr/local/bin/inboundparse /usr/local/bin/start.sh
 
-USER inboundparse
+# Stay root for the entrypoint. start.sh writes a root-owned /cert volume,
+# then drops to inboundparse before the SMTP process.
 ENV HOME=/home/inboundparse
 
 # Environment variables for acme.sh and SMTP server
 ENV CF_Token=""
 ENV CF_Zone_ID=""
 ENV DNS_API=""
-ENV ACME_SH_EMAIL=""
+ENV ACME_SH_EMAIL="devnull@localhost"
 ENV MXDOMAIN=""
 ENV WEBHOOK_URL=""
 ENV ENABLE_SPF="true"

README.md

@@ -183,8 +183,15 @@ You can configure InboundParse using environment variables or command line flags
 
 #### TLS Settings
 
-- `CERT_FILE`             Path to TLS certificate file (optional)
+The image entrypoint requests a Let's Encrypt certificate on startup when DNS credentials are set, then starts SMTP. No extra script is required. If those credentials are unset, or issuance fails, SMTP still starts without STARTTLS. A volume mounted at `/cert` keeps the certificate across restarts.
+
+- `CERT_FILE`             Path to TLS certificate file (optional; the entrypoint sets this when it has a certificate)
 - `KEY_FILE`              Path to TLS private key file (optional)
+- `MXDOMAIN`              Certificate domain (default: `SERVER_NAME`, then `mx.inboundparse.com`)
+- `ACME_SH_EMAIL`         Let's Encrypt account email (default: `devnull@localhost`)
+- `DNS_API`               acme.sh DNS provider (default: `dns_cf`)
+- `CF_Token`              Cloudflare API token (required for `dns_cf`)
+- `CF_Zone_ID`            Cloudflare zone id (required for `dns_cf`)
 
 #### Feature Flags
 

docs/providers/fly.io/README.md

@@ -6,11 +6,14 @@ The sample Fly config in this directory is [`fly.toml`](./fly.toml). Adjust app
 # From the directory that contains fly.toml
 fly deploy
 
-# Core secrets (adjust for your webhook and DNS/API provider — see `start.sh` / `Dockerfile` for ACME)
+# The image entrypoint issues the certificate. No extra start script.
+# ACME_SH_EMAIL defaults to devnull@localhost. SMTP still starts without
+# STARTTLS when the DNS secrets are unset or issuance fails.
 fly secrets set WEBHOOK_URL=https://your-webhook-url.com/api/webhook
 fly secrets set CF_Token=your-cloudflare-token
 fly secrets set CF_Zone_ID=your-zone-id
 fly secrets set MXDOMAIN=your-domain.com
+fly secrets set ACME_SH_EMAIL=you@your-domain.com
 
 # Optional: error tracking
 fly secrets set SENTRY_DSN=https://your-dsn@sentry.io/project-id

go.mod

@@ -1,6 +1,6 @@
 module inboundparse
 
-go 1.26.3
+go 1.26.10
 
 require (
 	github.com/emersion/go-msgauth v0.7.0
@@ -15,7 +15,8 @@ require (
 	github.com/rs/zerolog v1.35.1
 	github.com/stretchr/testify v1.11.1
 	github.com/zaccone/spf v0.0.0-20170817004109-76747b8658d9
-	golang.org/x/sync v0.20.0
+	golang.org/x/net v0.60.0
+	golang.org/x/sync v0.23.0
 )
 
 require (
@@ -34,12 +35,11 @@ require (
 	github.com/prometheus/common v0.67.5 // indirect
 	github.com/prometheus/procfs v0.20.1 // indirect
 	go.yaml.in/yaml/v2 v2.4.4 // indirect
-	golang.org/x/crypto v0.51.0 // indirect
-	golang.org/x/mod v0.36.0 // indirect
-	golang.org/x/net v0.54.0 // indirect
-	golang.org/x/sys v0.44.0 // indirect
-	golang.org/x/text v0.37.0 // indirect
-	golang.org/x/tools v0.45.0 // indirect
+	golang.org/x/crypto v0.57.0 // indirect
+	golang.org/x/mod v0.41.0 // indirect
+	golang.org/x/sys v0.48.0 // indirect
+	golang.org/x/text v0.42.0 // indirect
+	golang.org/x/tools v0.49.0 // indirect
 	google.golang.org/protobuf v1.36.11 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -73,20 +73,20 @@ go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=
 go.uber.org/goleak v1.3.0/go.mod h1:CoHD4mav9JJNrW/WLlf7HGZPjdw8EucARQHekz1X6bE=
 go.yaml.in/yaml/v2 v2.4.4 h1:tuyd0P+2Ont/d6e2rl3be67goVK4R6deVxCUX5vyPaQ=
 go.yaml.in/yaml/v2 v2.4.4/go.mod h1:gMZqIpDtDqOfM0uNfy0SkpRhvUryYH0Z6wdMYcacYXQ=
-golang.org/x/crypto v0.51.0 h1:IBPXwPfKxY7cWQZ38ZCIRPI50YLeevDLlLnyC5wRGTI=
-golang.org/x/crypto v0.51.0/go.mod h1:8AdwkbraGNABw2kOX6YFPs3WM22XqI4EXEd8g+x7Oc8=
-golang.org/x/mod v0.36.0 h1:JJjpVx6myfUsUdAzZuOSTTmRE0PfZeNWzzvKrP7amb4=
-golang.org/x/mod v0.36.0/go.mod h1:moc6ELqsWcOw5Ef3xVprK5ul/MvtVvkIXLziUOICjUQ=
-golang.org/x/net v0.54.0 h1:2zJIZAxAHV/OHCDTCOHAYehQzLfSXuf/5SoL/Dv6w/w=
-golang.org/x/net v0.54.0/go.mod h1:Sj4oj8jK6XmHpBZU/zWHw3BV3abl4Kvi+Ut7cQcY+cQ=
-golang.org/x/sync v0.20.0 h1:e0PTpb7pjO8GAtTs2dQ6jYa5BWYlMuX047Dco/pItO4=
-golang.org/x/sync v0.20.0/go.mod h1:9xrNwdLfx4jkKbNva9FpL6vEN7evnE43NNNJQ2LF3+0=
-golang.org/x/sys v0.44.0 h1:ildZl3J4uzeKP07r2F++Op7E9B29JRUy+a27EibtBTQ=
-golang.org/x/sys v0.44.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
-golang.org/x/text v0.37.0 h1:Cqjiwd9eSg8e0QAkyCaQTNHFIIzWtidPahFWR83rTrc=
-golang.org/x/text v0.37.0/go.mod h1:a5sjxXGs9hsn/AJVwuElvCAo9v8QYLzvavO5z2PiM38=
-golang.org/x/tools v0.45.0 h1:18qN3FAooORvApf5XjCXgsuayZOEtXf6JK18I3+ONa8=
-golang.org/x/tools v0.45.0/go.mod h1:LuUGqqaXcXMEFEruIVJVm5mgDD8vww/z/SR1gQ4uE/0=
+golang.org/x/crypto v0.57.0 h1:3ZVCjf8Ggz7zneR/EHRVx68Ctf+2pmIMP2UFhh9cC6M=
+golang.org/x/crypto v0.57.0/go.mod h1:Fdz0i5U6CoizGwLda9DttjSk6qlZo25zYNtR+ycvuZA=
+golang.org/x/mod v0.41.0 h1:qJmnOUb4YB+FsEuM3HcWucdZASCPGhsX6uljO6pog0c=
+golang.org/x/mod v0.41.0/go.mod h1:Ek9pY8RKWXwsWvd3rQiHYtMqkjSUV+s1Rj7j4H5Ur6o=
+golang.org/x/net v0.60.0 h1:79p50tfZlm0J9YfoDsSi639qSXNGVwEzOPLCxM2FsYU=
+golang.org/x/net v0.60.0/go.mod h1:2DA/G1UfVbCpQPeWTmMPGY7Cs2PkBkwu743bVX5PIVg=
+golang.org/x/sync v0.23.0 h1:KameEIfc1IkluZyXWLn39Wd4tURc6GbCiISGiZm2bQk=
+golang.org/x/sync v0.23.0/go.mod h1:sUUOizhqBxiL6pEWpqNLUiaJn1ShEbZ6BBqskPbjZm0=
+golang.org/x/sys v0.48.0 h1:bbX/i/6MgT9BVLM9RT1thmxL04yeTAhbEz4SyadbXoo=
+golang.org/x/sys v0.48.0/go.mod h1:hNLxWAXmnKAxqDtdwIYC4bM9oQPEecfsnNMuSxOs3og=
+golang.org/x/text v0.42.0 h1:JbOZXgfeCPU9gacVtYliJqOhD+zhrEqK4LfdpmlUZqI=
+golang.org/x/text v0.42.0/go.mod h1:ojzP1Z+2QtioaF8DTtO8K5q7JWVVYwZKenzujK0Zd0E=
+golang.org/x/tools v0.49.0 h1:3NI7VXzL9+1WZD52Dx2ttoPwD5DWrFGpl9mFZDlmisI=
+golang.org/x/tools v0.49.0/go.mod h1:SJNXV9DBKT0UbdttsQjbfJlAE/q+y36++zo3uL3N0Oo=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20240814211410-ddb44dafa142 h1:e7S5W7MGGLaSu8j3YjdezkZ+m1/Nm0uRVRMEMGk26Xs=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20240814211410-ddb44dafa142/go.mod h1:UqMtugtsSgubUsoxbuAoiCXvqvErP7Gf0so0mK9tHxU=
 google.golang.org/grpc v1.67.1 h1:zWnc1Vrcno+lHZCOofnIMvycFcc0QRGIzm9dhnDX68E=

internal/app/app.go

@@ -12,8 +12,6 @@ import (
 	"os/signal"
 	"syscall"
 	"time"
-
-	"golang.org/x/sync/errgroup"
 )
 
 // App represents the application
@@ -190,45 +188,31 @@ func (a *App) Start() error {
 	return nil
 }
 
-// Run runs the application with graceful shutdown
+// Run runs the application with graceful shutdown.
+// Signal handlers are installed before Start is launched. Start blocks in SMTP
+// Serve for the life of the process, so waiting for it to return would leave
+// SIGINT and SIGTERM unhandled while mail is accepted.
 func (a *App) Run() error {
-	// Start the application
-	if err := a.Start(); err != nil {
-		return err
-	}
-
-	// Set up graceful shutdown
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-
-	// Create error group for managing goroutines
-	g, ctx := errgroup.WithContext(ctx)
-
-	// Handle shutdown signals
 	sigChan := make(chan os.Signal, 1)
 	signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)
+	defer signal.Stop(sigChan)
 
-	g.Go(func() error {
-		select {
-		case sig := <-sigChan:
-			a.logger.Info().
-				Str("signal", sig.String()).
-				Msg("Received shutdown signal")
-			cancel()
-			return nil
-		case <-ctx.Done():
-			return ctx.Err()
-		}
-	})
+	// Buffered so the Start goroutine can send after Run has already returned
+	// on a signal. An unbuffered send would leak that goroutine.
+	startErr := make(chan error, 1)
+	go func() {
+		startErr <- a.Start()
+	}()
 
-	// Wait for context cancellation
-	g.Go(func() error {
-		<-ctx.Done()
+	select {
+	case sig := <-sigChan:
+		a.logger.Info().
+			Str("signal", sig.String()).
+			Msg("Received shutdown signal")
 		return a.Stop()
-	})
-
-	// Wait for all goroutines to complete
-	return g.Wait()
+	case err := <-startErr:
+		return err
+	}
 }
 
 // Stop stops the application gracefully