go-redis/example/disable-maintnotifications/README.md

Disable Maintenance Notifications Example

This example demonstrates how to use the go-redis client with maintenance notifications disabled.

What are Maintenance Notifications?

Maintenance notifications are a Redis Cloud feature that allows the server to notify clients about:

• Planned maintenance events
• Failover operations
• Node migrations
• Cluster topology changes

The go-redis client supports three modes:

• ModeDisabled: Client doesn't send CLIENT MAINT_NOTIFICATIONS ON command
• ModeEnabled: Client forcefully sends the command, interrupts connection on error
• ModeAuto (default): Client tries to send the command, disables feature on error

When to Disable Maintenance Notifications

You should disable maintenance notifications when:

1. Connecting to non-Redis Cloud / Redis Enterprise instances - Standard Redis servers don't support this feature
2. You want to handle failovers manually - Your application has custom failover logic
3. Minimizing client-side overhead - You want the simplest possible client behavior
4. The Redis server doesn't support the feature - Older Redis versions or forks

Usage

Basic Example

import (
    "github.com/redis/go-redis/v9"
    "github.com/redis/go-redis/v9/maintnotifications"
)

rdb := redis.NewClient(&redis.Options{
    Addr: "localhost:6379",

    // Explicitly disable maintenance notifications
    MaintNotificationsConfig: &maintnotifications.Config{
        Mode: maintnotifications.ModeDisabled,
    },
})
defer rdb.Close()

Cluster Client Example

rdbCluster := redis.NewClusterClient(&redis.ClusterOptions{
    Addrs: []string{"localhost:7000", "localhost:7001", "localhost:7002"},

    // Disable maintenance notifications for cluster
    MaintNotificationsConfig: &maintnotifications.Config{
        Mode: maintnotifications.ModeDisabled,
    },
})
defer rdbCluster.Close()

Default Behavior (ModeAuto)

If you don't specify MaintNotifications, the client defaults to ModeAuto:

// This uses ModeAuto by default
rdb := redis.NewClient(&redis.Options{
    Addr: "localhost:6379",
    // MaintNotificationsConfig: nil means ModeAuto
})

With ModeAuto, the client will:

1. Try to enable maintenance notifications
2. If the server doesn't support it, silently disable the feature
3. Continue normal operation

Running the Example

1. Start a Redis server:

   redis-server --port 6379
   

2. Run the example:

   go run main.go
   

Expected Output

=== Example 1: Explicitly Disabled ===
✓ Connected successfully (maintenance notifications disabled)
✓ SET operation successful
✓ GET operation successful: value1

=== Example 2: Default Behavior (ModeAuto) ===
✓ Connected successfully (maintenance notifications auto-enabled)

=== Example 3: Cluster Client with Disabled Notifications ===
Cluster not available (expected): ...

=== Example 4: Performance Comparison ===
✓ 1000 SET operations (disabled): 45ms
✓ 1000 SET operations (auto): 46ms

=== Cleanup ===
✓ Database flushed

=== Summary ===
Maintenance notifications can be disabled by setting:
  MaintNotificationsConfig: &maintnotifications.Config{
    Mode: maintnotifications.ModeDisabled,
  }

This is useful when:
  - Connecting to non-Redis Cloud instances
  - You want to handle failovers manually
  - You want to minimize client-side overhead
  - The Redis server doesn't support CLIENT MAINT_NOTIFICATIONS

Performance Impact

Disabling maintenance notifications has minimal performance impact. The main differences are:

1. Connection Setup: One less command (CLIENT MAINT_NOTIFICATIONS ON) during connection initialization
2. Runtime Overhead: No background processing of maintenance notifications
3. Memory Usage: Slightly lower memory footprint (no notification handlers)

In most cases, the performance difference is negligible (< 1%).