feat: allow configuration of ACME certificates duration

docs/content/https/acme.md

@@ -140,7 +140,11 @@ Please check the [configuration examples below](#configuration-examples) for mor
 
 Traefik automatically tracks the expiry date of ACME certificates it generates.
 
-If there are less than 30 days remaining before the certificate expires, Traefik will attempt to renew it automatically.
+By default, Traefik manages 90 days certificates,
+and starts to renew certificates 30 days before their expiry.
+
+When using a certificates resolver that issues certificates with custom durations,
+one can configure the certificates' duration with the [`certificatesDuration`](#certificatesduration) option.
 
 !!! info ""
     Certificates that are no longer used may still be renewed, as Traefik does not currently check if the certificate is being used before renewing.
@@ -533,6 +537,50 @@ docker run -v "/my/host/acme:/etc/traefik/acme" traefik
 !!! warning
     For concurrency reasons, this file cannot be shared across multiple instances of Traefik.
 
+### `certificatesDuration`
+
+_Optional, Default=2160_
+
+The `certificatesDuration` option defines the certificates' duration in hours.
+It defaults to `2160` (90 days) to follow Let's Encrypt certificates' duration.
+
+!!! warning "Traefik cannot manage certificates with a duration lower than 1 hour."
+
+```yaml tab="File (YAML)"
+certificatesResolvers:
+  myresolver:
+    acme:
+      # ...
+      certificatesDuration: 72
+      # ...
+```
+
+```toml tab="File (TOML)"
+[certificatesResolvers.myresolver.acme]
+  # ...
+  certificatesDuration=72
+  # ...
+```
+
+```bash tab="CLI"
+# ...
+--certificatesresolvers.myresolver.acme.certificatesduration=72
+# ...
+```
+
+`certificatesDuration` is used to calculate two durations:
+
+- `Renew Period`: the period before the end of the certificate duration, during which the certificate should be renewed.
+- `Renew Interval`: the interval between renew attempts.
+
+| Certificate Duration | Renew Period      | Renew Interval          |
+|----------------------|-------------------|-------------------------|
+| >= 1 year            | 4 months          | 1 week                  |
+| >= 90 days           | 30 days           | 1 day                   |
+| >= 7 days            | 1 day             | 1 hour                  |
+| >= 24 hours          | 6 hours           | 10 min                  |
+| < 24 hours           | 20 min            | 1 min                   |
+
 ### `preferredChain`
 
 _Optional, Default=""_

docs/content/https/ref-acme.toml

@@ -22,6 +22,14 @@
   #
   # caServer = "https://acme-staging-v02.api.letsencrypt.org/directory"
 
+  # The certificates' duration in hours.
+  # It defaults to 2160 (90 days) to follow Let's Encrypt certificates' duration.
+  #
+  # Optional
+  # Default: 2160
+  #
+  # certificatesDuration=2160
+
   # Preferred chain to use.
   #
   # If the CA offers multiple certificate chains, prefer the chain with an issuer matching this Subject Common Name.

docs/content/https/ref-acme.txt

@@ -21,6 +21,14 @@
 #
 --certificatesresolvers.myresolver.acme.caserver=https://acme-staging-v02.api.letsencrypt.org/directory
 
+# The certificates' duration in hours.
+# It defaults to 2160 (90 days) to follow Let's Encrypt certificates' duration.
+#
+# Optional
+# Default: 2160
+#
+--certificatesresolvers.myresolver.acme.certificatesDuration=2160
+
 # Preferred chain to use.
 #
 # If the CA offers multiple certificate chains, prefer the chain with an issuer matching this Subject Common Name.

docs/content/https/ref-acme.yaml

@@ -24,6 +24,14 @@ certificatesResolvers:
       #
       # caServer: "https://acme-staging-v02.api.letsencrypt.org/directory"
 
+      # The certificates' duration in hours.
+      # It defaults to 2160 (90 days) to follow Let's Encrypt certificates' duration.
+      #
+      # Optional
+      # Default: 2160
+      #
+      # certificatesDuration: 2160
+
       # Preferred chain to use.
       #
       # If the CA offers multiple certificate chains, prefer the chain with an issuer matching this Subject Common Name.

docs/content/reference/static-configuration/cli-ref.md

@@ -54,6 +54,9 @@ Certificates resolvers configuration. (Default: ```false```)
 `--certificatesresolvers.<name>.acme.caserver`:  
 CA server to use. (Default: ```https://acme-v02.api.letsencrypt.org/directory```)
 
+`--certificatesresolvers.<name>.acme.certificatesduration`:  
+Certificates' duration in hours. (Default: ```2160```)
+
 `--certificatesresolvers.<name>.acme.dnschallenge`:  
 Activate DNS-01 Challenge. (Default: ```false```)
 

docs/content/reference/static-configuration/env-ref.md

@@ -54,6 +54,9 @@ Certificates resolvers configuration. (Default: ```false```)
 `TRAEFIK_CERTIFICATESRESOLVERS_<NAME>_ACME_CASERVER`:  
 CA server to use. (Default: ```https://acme-v02.api.letsencrypt.org/directory```)
 
+`TRAEFIK_CERTIFICATESRESOLVERS_<NAME>_ACME_CERTIFICATESDURATION`:  
+Certificates' duration in hours. (Default: ```2160```)
+
 `TRAEFIK_CERTIFICATESRESOLVERS_<NAME>_ACME_DNSCHALLENGE`:  
 Activate DNS-01 Challenge. (Default: ```false```)
 

docs/content/reference/static-configuration/file.toml

@@ -358,6 +358,7 @@
     [certificatesResolvers.CertificateResolver0.acme]
       email = "foobar"
       caServer = "foobar"
+      certificatesDuration = 2160
       preferredChain = "foobar"
       storage = "foobar"
       keyType = "foobar"
@@ -376,6 +377,7 @@
     [certificatesResolvers.CertificateResolver1.acme]
       email = "foobar"
       caServer = "foobar"
+      certificatesDuration = 2160
       preferredChain = "foobar"
       storage = "foobar"
       keyType = "foobar"

docs/content/reference/static-configuration/file.yaml

@@ -376,6 +376,7 @@ certificatesResolvers:
     acme:
       email: foobar
       caServer: foobar
+      certificatesDuration: 2160
       preferredChain: foobar
       storage: foobar
       keyType: foobar
@@ -396,6 +397,7 @@ certificatesResolvers:
     acme:
       email: foobar
       caServer: foobar
+      certificatesDuration: 2160
       preferredChain: foobar
       storage: foobar
       keyType: foobar

pkg/anonymize/anonymize_config_test.go

@@ -916,6 +916,7 @@ func TestDo_staticConfiguration(t *testing.T) {
 			ACME: &acme.Configuration{
 				Email:                "acme Email",
 				CAServer:             "CAServer",
+				CertificatesDuration: 42,
 				PreferredChain:       "foobar",
 				Storage:              "Storage",
 				KeyType:              "MyKeyType",

pkg/anonymize/testdata/anonymized-static-config.json

@@ -426,6 +426,7 @@
         "preferredChain": "foobar",
         "storage": "Storage",
         "keyType": "MyKeyType",
+        "certificatesDuration": 42,
         "dnsChallenge": {
           "provider": "DNSProvider",
           "delayBeforeCheck": "42ns",

pkg/provider/acme/provider.go

@@ -39,6 +39,7 @@ type Configuration struct {
 	Storage              string `description:"Storage to use." json:"storage,omitempty" toml:"storage,omitempty" yaml:"storage,omitempty" export:"true"`
 	KeyType              string `description:"KeyType used for generating certificate private key. Allow value 'EC256', 'EC384', 'RSA2048', 'RSA4096', 'RSA8192'." json:"keyType,omitempty" toml:"keyType,omitempty" yaml:"keyType,omitempty" export:"true"`
 	EAB                  *EAB   `description:"External Account Binding to use." json:"eab,omitempty" toml:"eab,omitempty" yaml:"eab,omitempty"`
+	CertificatesDuration int    `description:"Certificates' duration in hours." json:"certificatesDuration,omitempty" toml:"certificatesDuration,omitempty" yaml:"certificatesDuration,omitempty" export:"true"`
 
 	DNSChallenge  *DNSChallenge  `description:"Activate DNS-01 Challenge." json:"dnsChallenge,omitempty" toml:"dnsChallenge,omitempty" yaml:"dnsChallenge,omitempty" label:"allowEmpty" file:"allowEmpty" export:"true"`
 	HTTPChallenge *HTTPChallenge `description:"Activate HTTP-01 Challenge." json:"httpChallenge,omitempty" toml:"httpChallenge,omitempty" yaml:"httpChallenge,omitempty" label:"allowEmpty" file:"allowEmpty" export:"true"`
@@ -50,6 +51,7 @@ func (a *Configuration) SetDefaults() {
 	a.CAServer = lego.LEDirectoryProduction
 	a.Storage = "acme.json"
 	a.KeyType = "RSA4096"
+	a.CertificatesDuration = 3 * 30 * 24 // 90 Days
 }
 
 // CertAndStore allows mapping a TLS certificate to a TLS store.
@@ -133,6 +135,10 @@ func (p *Provider) Init() error {
 		return errors.New("unable to initialize ACME provider with no storage location for the certificates")
 	}
 
+	if p.CertificatesDuration < 1 {
+		return errors.New("cannot manage certificates with duration lower than 1 hour")
+	}
+
 	var err error
 	p.account, err = p.Store.GetAccount(p.ResolverName)
 	if err != nil {
@@ -177,7 +183,9 @@ func isAccountMatchingCaServer(ctx context.Context, accountURI, serverURI string
 // Provide allows the file provider to provide configurations to traefik
 // using the given Configuration channel.
 func (p *Provider) Provide(configurationChan chan<- dynamic.Message, pool *safe.Pool) error {
-	ctx := log.With(context.Background(), log.Str(log.ProviderName, p.ResolverName+".acme"))
+	ctx := log.With(context.Background(),
+		log.Str(log.ProviderName, p.ResolverName+".acme"),
+		log.Str("ACME CA", p.Configuration.CAServer))
 
 	p.pool = pool
 
@@ -187,14 +195,18 @@ func (p *Provider) Provide(configurationChan chan<- dynamic.Message, pool *safe.
 	p.configurationChan = configurationChan
 	p.refreshCertificates()
 
-	p.renewCertificates(ctx)
+	renewPeriod, renewInterval := getCertificateRenewDurations(p.CertificatesDuration)
+	log.FromContext(ctx).Debugf("Attempt to renew certificates %q before expiry and check every %q",
+		renewPeriod, renewInterval)
 
-	ticker := time.NewTicker(24 * time.Hour)
+	p.renewCertificates(ctx, renewPeriod)
+
+	ticker := time.NewTicker(renewInterval)
 	pool.GoCtx(func(ctxPool context.Context) {
 		for {
 			select {
 			case <-ticker.C:
-				p.renewCertificates(ctx)
+				p.renewCertificates(ctx, renewPeriod)
 			case <-ctxPool.Done():
 				ticker.Stop()
 				return
@@ -515,6 +527,24 @@ func (p *Provider) addCertificateForDomain(domain types.Domain, certificate, key
 	p.certsChan <- &CertAndStore{Certificate: Certificate{Certificate: certificate, Key: key, Domain: domain}, Store: tlsStore}
 }
 
+// getCertificateRenewDurations returns renew durations calculated from the given certificatesDuration in hours.
+// The first (RenewPeriod) is the period before the end of the certificate duration, during which the certificate should be renewed.
+// The second (RenewInterval) is the interval between renew attempts.
+func getCertificateRenewDurations(certificatesDuration int) (time.Duration, time.Duration) {
+	switch {
+	case certificatesDuration >= 265*24: // >= 1 year
+		return 4 * 30 * 24 * time.Hour, 7 * 24 * time.Hour // 4 month, 1 week
+	case certificatesDuration >= 3*30*24: // >= 90 days
+		return 30 * 24 * time.Hour, 24 * time.Hour // 30 days, 1 day
+	case certificatesDuration >= 7*24: // >= 7 days
+		return 24 * time.Hour, time.Hour // 1 days, 1 hour
+	case certificatesDuration >= 24: // >= 1 days
+		return 6 * time.Hour, 10 * time.Minute // 6 hours, 10 minutes
+	default:
+		return 20 * time.Minute, time.Minute
+	}
+}
+
 // deleteUnnecessaryDomains deletes from the configuration :
 // - Duplicated domains
 // - Domains which are checked by wildcard domain.
@@ -637,15 +667,14 @@ func (p *Provider) refreshCertificates() {
 	p.configurationChan <- conf
 }
 
-func (p *Provider) renewCertificates(ctx context.Context) {
+func (p *Provider) renewCertificates(ctx context.Context, renewPeriod time.Duration) {
 	logger := log.FromContext(ctx)
 
 	logger.Info("Testing certificate renew...")
 	for _, cert := range p.certificates {
 		crt, err := getX509Certificate(ctx, &cert.Certificate)
 		// If there's an error, we assume the cert is broken, and needs update
-		// <= 30 days left, renew certificate
-		if err != nil || crt == nil || crt.NotAfter.Before(time.Now().Add(24*30*time.Hour)) {
+		if err != nil || crt == nil || crt.NotAfter.Before(time.Now().Add(renewPeriod)) {
 			client, err := p.getClient()
 			if err != nil {
 				logger.Infof("Error renewing certificate from LE : %+v, %v", cert.Domain, err)

pkg/provider/acme/provider_test.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"crypto/tls"
 	"testing"
+	"time"
 
 	"github.com/go-acme/lego/v4/certcrypto"
 	"github.com/stretchr/testify/assert"
@@ -592,3 +593,53 @@ func TestInitAccount(t *testing.T) {
 		})
 	}
 }
+
+func Test_getCertificateRenewDurations(t *testing.T) {
+	testCases := []struct {
+		desc                  string
+		certificatesDurations int
+		expectRenewPeriod     time.Duration
+		expectRenewInterval   time.Duration
+	}{
+		{
+			desc:                  "Less than 24 Hours certificates: 20 minutes renew period, 1 minutes renew interval",
+			certificatesDurations: 1,
+			expectRenewPeriod:     time.Minute * 20,
+			expectRenewInterval:   time.Minute,
+		},
+		{
+			desc:                  "1 Year certificates: 2 months renew period, 1 week renew interval",
+			certificatesDurations: 24 * 365,
+			expectRenewPeriod:     time.Hour * 24 * 30 * 4,
+			expectRenewInterval:   time.Hour * 24 * 7,
+		},
+		{
+			desc:                  "90 Days certificates: 30 days renew period, 1 day renew interval",
+			certificatesDurations: 24 * 90,
+			expectRenewPeriod:     time.Hour * 24 * 30,
+			expectRenewInterval:   time.Hour * 24,
+		},
+		{
+			desc:                  "7 Days certificates: 1 days renew period, 1 hour renew interval",
+			certificatesDurations: 24 * 7,
+			expectRenewPeriod:     time.Hour * 24,
+			expectRenewInterval:   time.Hour,
+		},
+		{
+			desc:                  "24 Hours certificates: 6 hours renew period, 10 minutes renew interval",
+			certificatesDurations: 24,
+			expectRenewPeriod:     time.Hour * 6,
+			expectRenewInterval:   time.Minute * 10,
+		},
+	}
+	for _, test := range testCases {
+		test := test
+		t.Run(test.desc, func(t *testing.T) {
+			t.Parallel()
+
+			renewPeriod, renewInterval := getCertificateRenewDurations(test.certificatesDurations)
+			assert.Equal(t, test.expectRenewPeriod, renewPeriod)
+			assert.Equal(t, test.expectRenewInterval, renewInterval)
+		})
+	}
+}