feat: add custom Duration type for config values

pkg/bootstrap/builder.go

@@ -19,7 +19,9 @@ import (
 	"os"
 	"strconv"
 	"strings"
+	"time"
 
+	"go.probo.inc/probo/pkg/duration"
 	"go.probo.inc/probo/pkg/probod"
 )
 
@@ -149,12 +151,12 @@ func (b *Builder) Build() (*probod.FullConfig, error) {
 					},
 				},
 				Slack: probod.SlackConfig{
-					SenderInterval: b.getEnvIntOrDefault("SLACK_SENDER_INTERVAL", 60),
+					SenderInterval: b.getEnvDurationOrDefault("SLACK_SENDER_INTERVAL", 60*time.Second),
 					SigningSecret:  b.getEnv("CONNECTOR_SLACK_SIGNING_SECRET"),
 				},
 				Webhook: probod.WebhookConfig{
-					SenderInterval: b.getEnvIntOrDefault("WEBHOOK_SENDER_INTERVAL", 5),
-					CacheTTL:       b.getEnvIntOrDefault("WEBHOOK_CACHE_TTL", 86400),
+					SenderInterval: b.getEnvDurationOrDefault("WEBHOOK_SENDER_INTERVAL", 5*time.Second),
+					CacheTTL:       b.getEnvDurationOrDefault("WEBHOOK_CACHE_TTL", 24*time.Hour),
 				},
 			},
 			LLM: probod.LLMSettings{
@@ -451,6 +453,20 @@ func (b *Builder) getEnvIntOrDefault(key string, defaultValue int) int {
 	return defaultValue
 }
 
+func (b *Builder) getEnvDurationOrDefault(key string, defaultValue time.Duration) duration.Duration {
+	if value := b.getEnv(key); value != "" {
+		if intValue, err := strconv.ParseInt(value, 10, 64); err == nil {
+			return duration.Duration(time.Duration(intValue) * time.Second)
+		}
+
+		if parsed, err := time.ParseDuration(value); err == nil {
+			return duration.Duration(parsed)
+		}
+	}
+
+	return duration.Duration(defaultValue)
+}
+
 func (b *Builder) getEnvFloatOrDefault(key string, defaultValue float64) float64 {
 	if value := b.getEnv(key); value != "" {
 		if floatValue, err := strconv.ParseFloat(value, 64); err == nil {

pkg/bootstrap/builder_test.go

@@ -18,9 +18,11 @@ import (
 	"os"
 	"path/filepath"
 	"testing"
+	"time"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"go.probo.inc/probo/pkg/duration"
 	"go.probo.inc/probo/pkg/probod"
 )
 
@@ -156,10 +158,10 @@ func TestBuilder_Build_Defaults(t *testing.T) {
 	assert.Equal(t, "localhost:1025", cfg.Probod.Notifications.Mailer.SMTP.Addr)
 	assert.False(t, cfg.Probod.Notifications.Mailer.SMTP.TLSRequired)
 	assert.Equal(t, 60, cfg.Probod.Notifications.Mailer.MailerInterval)
-	assert.Equal(t, 60, cfg.Probod.Notifications.Slack.SenderInterval)
+	assert.Equal(t, duration.Duration(60*time.Second), cfg.Probod.Notifications.Slack.SenderInterval)
 	assert.Empty(t, cfg.Probod.Notifications.Slack.SigningSecret)
-	assert.Equal(t, 5, cfg.Probod.Notifications.Webhook.SenderInterval)
-	assert.Equal(t, 86400, cfg.Probod.Notifications.Webhook.CacheTTL)
+	assert.Equal(t, duration.Duration(5*time.Second), cfg.Probod.Notifications.Webhook.SenderInterval)
+	assert.Equal(t, duration.Duration(24*time.Hour), cfg.Probod.Notifications.Webhook.CacheTTL)
 
 	// LLM config — defaults
 	assert.Equal(t, "openai", cfg.Probod.LLM.Defaults.Provider)
@@ -243,8 +245,9 @@ func TestBuilder_Build_CustomValues(t *testing.T) {
 	env["AWS_ENDPOINT"] = "https://s3.example.com"
 	env["AWS_USE_PATH_STYLE"] = "true"
 	// Notifications
-	env["WEBHOOK_SENDER_INTERVAL"] = "10"
-	env["WEBHOOK_CACHE_TTL"] = "3600"
+	env["SLACK_SENDER_INTERVAL"] = "2m"
+	env["WEBHOOK_SENDER_INTERVAL"] = "10s"
+	env["WEBHOOK_CACHE_TTL"] = "1h"
 	env["CONNECTOR_SLACK_SIGNING_SECRET"] = "slack-signing-secret"
 	// LLM — providers
 	env["OPENAI_API_KEY"] = "sk-test-key"
@@ -318,9 +321,10 @@ func TestBuilder_Build_CustomValues(t *testing.T) {
 	assert.Equal(t, "https://s3.example.com", cfg.Probod.AWS.Endpoint)
 	assert.True(t, cfg.Probod.AWS.UsePathStyle)
 	// Notifications
+	assert.Equal(t, duration.Duration(2*time.Minute), cfg.Probod.Notifications.Slack.SenderInterval)
 	assert.Equal(t, "slack-signing-secret", cfg.Probod.Notifications.Slack.SigningSecret)
-	assert.Equal(t, 10, cfg.Probod.Notifications.Webhook.SenderInterval)
-	assert.Equal(t, 3600, cfg.Probod.Notifications.Webhook.CacheTTL)
+	assert.Equal(t, duration.Duration(10*time.Second), cfg.Probod.Notifications.Webhook.SenderInterval)
+	assert.Equal(t, duration.Duration(time.Hour), cfg.Probod.Notifications.Webhook.CacheTTL)
 	// LLM — providers
 	assert.Equal(t, "openai", cfg.Probod.LLM.Providers["openai"].Type)
 	assert.Equal(t, "sk-test-key", cfg.Probod.LLM.Providers["openai"].APIKey)

pkg/duration/duration.go

@@ -0,0 +1,52 @@
+// Copyright (c) 2026 Probo Inc <hello@getprobo.com>.
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+package duration
+
+import (
+	"encoding/json"
+	"fmt"
+	"time"
+)
+
+type Duration time.Duration
+
+func (d Duration) MarshalJSON() ([]byte, error) {
+	return json.Marshal(d.String())
+}
+
+func (d *Duration) UnmarshalJSON(data []byte) error {
+	var seconds int64
+	if err := json.Unmarshal(data, &seconds); err == nil {
+		*d = Duration(time.Duration(seconds) * time.Second)
+		return nil
+	}
+
+	var value string
+	if err := json.Unmarshal(data, &value); err == nil {
+		parsed, err := time.ParseDuration(value)
+		if err != nil {
+			return fmt.Errorf("cannot parse duration: %w", err)
+		}
+
+		*d = Duration(parsed)
+		return nil
+	}
+
+	return fmt.Errorf("cannot parse duration from %s", string(data))
+}
+
+func (d Duration) String() string {
+	return time.Duration(d).String()
+}

pkg/duration/duration_test.go

@@ -0,0 +1,70 @@
+// Copyright (c) 2026 Probo Inc <hello@getprobo.com>.
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+package duration_test
+
+import (
+	"encoding/json"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"go.probo.inc/probo/pkg/duration"
+)
+
+func TestDurationUnmarshalJSONInt(t *testing.T) {
+	var got duration.Duration
+	err := json.Unmarshal([]byte(`60`), &got)
+	require.NoError(t, err)
+
+	assert.Equal(t, duration.Duration(60*time.Second), got)
+}
+
+func TestDurationUnmarshalJSONString(t *testing.T) {
+	var got duration.Duration
+	err := json.Unmarshal([]byte(`"5m"`), &got)
+	require.NoError(t, err)
+
+	assert.Equal(t, duration.Duration(5*time.Minute), got)
+}
+
+func TestDurationMarshalJSONRoundTrip(t *testing.T) {
+	want := duration.Duration(90 * time.Second)
+
+	data, err := json.Marshal(want)
+	require.NoError(t, err)
+	assert.Equal(t, `"1m30s"`, string(data))
+
+	var got duration.Duration
+	err = json.Unmarshal(data, &got)
+	require.NoError(t, err)
+	assert.Equal(t, want, got)
+}
+
+func TestDurationUnmarshalJSONInvalid(t *testing.T) {
+	tests := []string{
+		`true`,
+		`1.5`,
+		`"later"`,
+	}
+
+	for _, tt := range tests {
+		t.Run(tt, func(t *testing.T) {
+			var got duration.Duration
+			err := json.Unmarshal([]byte(tt), &got)
+			require.Error(t, err)
+		})
+	}
+}

pkg/probod/notifications_config.go

@@ -14,13 +14,15 @@
 
 package probod
 
+import "go.probo.inc/probo/pkg/duration"
+
 type NotificationsConfig struct {
 	Mailer  MailerConfig  `json:"mailer"`
 	Slack   SlackConfig   `json:"slack"`
 	Webhook WebhookConfig `json:"webhook"`
 }
 
 type WebhookConfig struct {
-	SenderInterval int `json:"sender-interval"`
-	CacheTTL       int `json:"cache-ttl"`
+	SenderInterval duration.Duration `json:"sender-interval"`
+	CacheTTL       duration.Duration `json:"cache-ttl"`
 }

pkg/probod/probod.go

@@ -31,6 +31,7 @@ import (
 
 	"go.probo.inc/probo/packages/emails"
 	pemutil "go.probo.inc/probo/pkg/crypto/pem"
+	"go.probo.inc/probo/pkg/duration"
 
 	"github.com/aws/aws-sdk-go-v2/service/s3"
 	proxyproto "github.com/pires/go-proxyproto"
@@ -195,11 +196,11 @@ func New() *Implm {
 					},
 				},
 				Slack: SlackConfig{
-					SenderInterval: 60,
+					SenderInterval: duration.Duration(60 * time.Second),
 				},
 				Webhook: WebhookConfig{
-					SenderInterval: 5,
-					CacheTTL:       86400,
+					SenderInterval: duration.Duration(5 * time.Second),
+					CacheTTL:       duration.Duration(24 * time.Hour),
 				},
 			},
 			CustomDomains: CustomDomainsConfig{
@@ -589,7 +590,7 @@ func (impl *Implm) Run(
 
 	slackSenderCtx, stopSlackSender := context.WithCancel(context.Background())
 	slackSender := slack.NewSender(pgClient, l.Named("slack-sender"), encryptionKey, slack.Config{
-		Interval: time.Duration(impl.cfg.Notifications.Slack.SenderInterval) * time.Second,
+		Interval: time.Duration(impl.cfg.Notifications.Slack.SenderInterval),
 	})
 	wg.Go(
 		func() {
@@ -601,8 +602,8 @@ func (impl *Implm) Run(
 
 	webhookSenderCtx, stopWebhookSender := context.WithCancel(context.Background())
 	webhookSender := webhook.NewSender(pgClient, l.Named("webhook-sender"), webhook.Config{
-		Interval:      time.Duration(impl.cfg.Notifications.Webhook.SenderInterval) * time.Second,
-		CacheTTL:      time.Duration(impl.cfg.Notifications.Webhook.CacheTTL) * time.Second,
+		Interval:      time.Duration(impl.cfg.Notifications.Webhook.SenderInterval),
+		CacheTTL:      time.Duration(impl.cfg.Notifications.Webhook.CacheTTL),
 		EncryptionKey: encryptionKey,
 	})
 	wg.Go(

pkg/probod/slack_config.go

@@ -14,7 +14,9 @@
 
 package probod
 
+import "go.probo.inc/probo/pkg/duration"
+
 type SlackConfig struct {
-	SenderInterval int    `json:"sender-interval"`
-	SigningSecret  string `json:"signing-secret"`
+	SenderInterval duration.Duration `json:"sender-interval"`
+	SigningSecret  string            `json:"signing-secret"`
 }