feat: domain blocker plugin

docs/creating-a-plugin.md

@@ -7,6 +7,7 @@ ButterRobot organizes plugins into different categories:
 - **Development**: Utility plugins like `ping`
 - **Fun**: Entertainment plugins like dice rolling, coin flipping
 - **Social**: Social media related plugins like URL transformers/expanders
+- **Security**: Moderation and protection features like domain blocking
 
 When creating a new plugin, consider which category it fits into and place it in the appropriate directory.
 
@@ -59,6 +60,91 @@ func (p *MarcoPlugin) OnMessage(msg *model.Message, config map[string]interface{
 }
 ```
 
+### Configuration-Enabled Plugin
+
+This plugin requires configuration to be set in the admin interface. It demonstrates how to create plugins that need channel-specific configuration:
+
+```go
+package security
+
+import (
+	"fmt"
+	"regexp"
+	"strings"
+
+	"git.nakama.town/fmartingr/butterrobot/internal/model"
+	"git.nakama.town/fmartingr/butterrobot/internal/plugin"
+)
+
+// DomainBlockPlugin is a plugin that blocks messages containing links from specific domains
+type DomainBlockPlugin struct {
+	plugin.BasePlugin
+}
+
+// New creates a new DomainBlockPlugin instance
+func New() *DomainBlockPlugin {
+	return &DomainBlockPlugin{
+		BasePlugin: plugin.BasePlugin{
+			ID:             "security.domainblock",
+			Name:           "Domain Blocker",
+			Help:           "Blocks messages containing links from configured domains",
+			ConfigRequired: true, // Mark this plugin as requiring configuration
+		},
+	}
+}
+
+// OnMessage processes incoming messages
+func (p *DomainBlockPlugin) OnMessage(msg *model.Message, config map[string]interface{}) []*model.Message {
+	// Get blocked domains from config
+	blockedDomainsStr, ok := config["blocked_domains"].(string)
+	if !ok || blockedDomainsStr == "" {
+		return nil // No blocked domains configured
+	}
+
+	// Split and clean blocked domains
+	blockedDomains := strings.Split(blockedDomainsStr, ",")
+	for i, domain := range blockedDomains {
+		blockedDomains[i] = strings.ToLower(strings.TrimSpace(domain))
+	}
+
+	// Extract domains from message
+	urlRegex := regexp.MustCompile(`https?://([^\s/$.?#].[^\s]*)`)
+	matches := urlRegex.FindAllStringSubmatch(msg.Text, -1)
+	
+	// Check if any extracted domains are blocked
+	for _, match := range matches {
+		if len(match) < 2 {
+			continue
+		}
+		
+		domain := strings.ToLower(match[1])
+		
+		for _, blockedDomain := range blockedDomains {
+			if blockedDomain == "" {
+				continue
+			}
+			
+			if strings.HasSuffix(domain, blockedDomain) || domain == blockedDomain {
+				// Domain is blocked, create warning message
+				response := &model.Message{
+					Text:    fmt.Sprintf("⚠️ Message contained a link to blocked domain: %s", blockedDomain),
+					Chat:    msg.Chat,
+					ReplyTo: msg.ID,
+					Channel: msg.Channel,
+				}
+				return []*model.Message{response}
+			}
+		}
+	}
+
+	return nil
+}
+
+func init() {
+	plugin.Register(New())
+}
+```
+
 ### Advanced Example: URL Transformer
 
 This more complex plugin transforms URLs, useful for improving media embedding in chat platforms:
@@ -143,6 +229,36 @@ func (p *TwitterExpander) OnMessage(msg *model.Message, config map[string]interf
 }
 ```
 
+## Enabling Configuration for Plugins
+
+To indicate that your plugin requires configuration:
+
+1. Set `ConfigRequired: true` in the BasePlugin struct:
+   ```go
+   BasePlugin: plugin.BasePlugin{
+       ID:             "myplugin.id",
+       Name:           "Plugin Name",
+       Help:           "Help text",
+       ConfigRequired: true,
+   },
+   ```
+
+2. Access the configuration in the OnMessage method:
+   ```go
+   func (p *MyPlugin) OnMessage(msg *model.Message, config map[string]interface{}) []*model.Message {
+       // Extract configuration values
+       configValue, ok := config["some_config_key"].(string)
+       if !ok || configValue == "" {
+           // Handle missing or empty configuration
+           return nil
+       }
+       
+       // Use the configuration...
+   }
+   ```
+
+3. The admin interface will show a "Configure" button for plugins that require configuration.
+
 ## Registering Plugins
 
 To use the plugin, register it in your application:
@@ -161,3 +277,11 @@ func (a *App) Run() error {
     // ...
 }
 ```
+
+Alternatively, you can register your plugin in its init() function:
+
+```go
+func init() {
+    plugin.Register(New())
+}
+```

docs/plugins.md

@@ -14,6 +14,10 @@
 
 - Remind Me: Reply to a message with `!remindme <duration>` to set a reminder. Supported duration units: y (years), mo (months), d (days), h (hours), m (minutes), s (seconds). Examples: `!remindme 1y` for 1 year, `!remindme 3mo` for 3 months, `!remindme 2d` for 2 days, `!remindme 3h` for 3 hours. The bot will mention you with a reminder after the specified time.
 
+### Security
+
+- Domain Blocker: Blocks messages containing links from specified domains. Configure it per channel with a comma-separated list of domains to block. When a message contains a link matching any of the blocked domains, the bot will notify that the message contained a blocked domain. This plugin requires configuration through the admin interface.
+
 ### Social Media
 
 - Twitter Link Expander: Automatically converts twitter.com and x.com links to fxtwitter.com links and removes tracking parameters. This allows for better media embedding in chat platforms.

internal/admin/admin.go

@@ -98,6 +98,7 @@ func New(cfg *config.Config, database *db.Database, version string) *Admin {
 		"channel_detail.html",
 		"plugin_list.html",
 		"channel_plugins_list.html",
+		"channel_plugin_config.html",
 	}
 
 	for _, tf := range templateFiles {
@@ -143,6 +144,7 @@ func (a *Admin) RegisterRoutes(mux *http.ServeMux) {
 	mux.HandleFunc("/admin/channels", a.handleChannelList)
 	mux.HandleFunc("/admin/channels/", a.handleChannelDetail)
 	mux.HandleFunc("/admin/channelplugins", a.handleChannelPluginList)
+	mux.HandleFunc("/admin/channelplugins/config/", a.handleChannelPluginConfig)
 	mux.HandleFunc("/admin/channelplugins/", a.handleChannelPluginDetailOrDelete)
 }
 
@@ -628,6 +630,96 @@ func (a *Admin) handleChannelPluginList(w http.ResponseWriter, r *http.Request)
 	})
 }
 
+// handleChannelPluginConfig handles the channel plugin configuration route
+func (a *Admin) handleChannelPluginConfig(w http.ResponseWriter, r *http.Request) {
+	// Check if user is logged in
+	if !a.isLoggedIn(r) {
+		http.Redirect(w, r, "/admin/login", http.StatusSeeOther)
+		return
+	}
+
+	// Extract channel plugin ID from path
+	path := r.URL.Path
+	channelPluginID := strings.TrimPrefix(path, "/admin/channelplugins/config/")
+
+	// Convert channel plugin ID to int64
+	id, err := strconv.ParseInt(channelPluginID, 10, 64)
+	if err != nil {
+		http.Error(w, "Invalid channel plugin ID", http.StatusBadRequest)
+		return
+	}
+
+	// Get the channel plugin
+	channelPlugin, err := a.db.GetChannelPluginByID(id)
+	if err != nil {
+		http.Error(w, "Channel plugin not found", http.StatusNotFound)
+		return
+	}
+
+	// Get the plugin
+	p, err := plugin.Get(channelPlugin.PluginID)
+	if err != nil {
+		http.Error(w, "Plugin not found", http.StatusNotFound)
+		return
+	}
+
+	// Handle form submission
+	if r.Method == http.MethodPost {
+		// Parse form
+		if err := r.ParseForm(); err != nil {
+			http.Error(w, "Bad request", http.StatusBadRequest)
+			return
+		}
+
+		// Create config map from form values
+		config := make(map[string]interface{})
+		
+		// Process form values based on plugin type
+		if channelPlugin.PluginID == "security.domainblock" {
+			// Get blocked domains from form
+			blockedDomains := r.FormValue("blocked_domains")
+			config["blocked_domains"] = blockedDomains
+		} else {
+			// Generic handling for other plugins
+			for key, values := range r.Form {
+				if key == "form_submitted" {
+					continue
+				}
+				if len(values) == 1 {
+					config[key] = values[0]
+				} else {
+					config[key] = values
+				}
+			}
+		}
+
+		// Update plugin configuration
+		if err := a.db.UpdateChannelPluginConfig(id, config); err != nil {
+			http.Error(w, "Failed to update plugin configuration", http.StatusInternalServerError)
+			return
+		}
+
+		// Get the channel to redirect back to the channel detail page
+		channel, err := a.db.GetChannelByID(channelPlugin.ChannelID)
+		if err != nil {
+			a.addFlash(w, r, "Plugin configuration updated", "success")
+			http.Redirect(w, r, "/admin/channelplugins", http.StatusSeeOther)
+			return
+		}
+
+		a.addFlash(w, r, "Plugin configuration updated", "success")
+		http.Redirect(w, r, fmt.Sprintf("/admin/channels/%d", channel.ID), http.StatusSeeOther)
+		return
+	}
+
+	// Render template
+	a.render(w, r, "channel_plugin_config.html", TemplateData{
+		Title:         "Configure Plugin: " + p.GetName(),
+		ChannelPlugin: channelPlugin,
+		Plugins:       map[string]model.Plugin{channelPlugin.PluginID: p},
+	})
+}
+
 // handleChannelPluginDetailOrDelete handles the channel plugin detail or delete route
 func (a *Admin) handleChannelPluginDetailOrDelete(w http.ResponseWriter, r *http.Request) {
 	// Check if user is logged in

internal/admin/templates/channel_detail.html

@@ -68,6 +68,10 @@
                                             {{if $channelPlugin.Enabled}}Disable{{else}}Enable{{end}}
                                         </button>
                                     </form>
+                                    {{$plugin := index $.Plugins $pluginID}}
+                                    {{if $plugin.RequiresConfig}}
+                                    <a href="/admin/channelplugins/config/{{$channelPlugin.ID}}" class="btn btn-info btn-sm">Configure</a>
+                                    {{end}}
                                     <form method="post" action="/admin/channelplugins/{{$channelPlugin.ID}}/delete" class="d-inline">
                                         <button type="submit" class="btn btn-danger btn-sm"
                                             onclick="return confirm('Are you sure you want to remove this plugin?')">Remove</button>

internal/admin/templates/channel_plugin_config.html

@@ -0,0 +1,37 @@
+{{define "content"}}
+<div class="row">
+    <div class="col-md-12">
+        <div class="card">
+            <div class="card-header">
+                <h3 class="card-title">Configure Plugin: {{(index .Plugins .ChannelPlugin.PluginID).GetName}}</h3>
+            </div>
+            <div class="card-body">
+                <form method="post">
+                    <!-- Plugin configuration fields -->
+                    {{if eq .ChannelPlugin.PluginID "security.domainblock"}}
+                    <div class="mb-3">
+                        <label class="form-label">Blocked Domains</label>
+                        <input type="text" class="form-control" name="blocked_domains"
+                               value="{{with .ChannelPlugin.Config}}{{index . "blocked_domains"}}{{end}}"
+                               placeholder="example.com, evil.org, ads.com">
+                        <div class="form-text text-muted">
+                            Enter comma-separated list of domains to block (e.g., example.com, evil.org).
+                            Messages containing links to these domains will be blocked.
+                        </div>
+                    </div>
+                    {{else}}
+                    <div class="alert alert-warning">
+                        This plugin doesn't have specific configuration fields implemented yet.
+                    </div>
+                    {{end}}
+
+                    <div class="form-footer">
+                        <button type="submit" class="btn btn-primary">Save Configuration</button>
+                        <a href="/admin/channels/{{.ChannelPlugin.ChannelID}}" class="btn btn-secondary">Cancel</a>
+                    </div>
+                </form>
+            </div>
+        </div>
+    </div>
+</div>
+{{end}}

internal/admin/templates/channel_plugins_list.html

@@ -38,6 +38,10 @@
                                                 {{if $channelPlugin.Enabled}}Disable{{else}}Enable{{end}}
                                             </button>
                                         </form>
+                                        {{$plugin := index $.Plugins $pluginID}}
+                                        {{if $plugin.ConfigRequired}}
+                                            <a href="/admin/channelplugins/config/{{$channelPlugin.ID}}" class="btn btn-info btn-sm">Configure</a>
+                                        {{end}}
                                         <form method="post" action="/admin/channelplugins/{{$channelPlugin.ID}}/delete" class="d-inline">
                                             <button type="submit" class="btn btn-danger btn-sm"
                                                 onclick="return confirm('Are you sure you want to remove this plugin?')">Remove</button>

internal/app/app.go

@@ -20,6 +20,7 @@ import (
 	"git.nakama.town/fmartingr/butterrobot/internal/model"
 	"git.nakama.town/fmartingr/butterrobot/internal/platform"
 	"git.nakama.town/fmartingr/butterrobot/internal/plugin"
+	"git.nakama.town/fmartingr/butterrobot/internal/plugin/domainblock"
 	"git.nakama.town/fmartingr/butterrobot/internal/plugin/fun"
 	"git.nakama.town/fmartingr/butterrobot/internal/plugin/ping"
 	"git.nakama.town/fmartingr/butterrobot/internal/plugin/reminder"
@@ -87,10 +88,8 @@ func (a *App) Run() error {
 	plugin.Register(fun.NewLoquito())
 	plugin.Register(social.NewTwitterExpander())
 	plugin.Register(social.NewInstagramExpander())
-
-	// Register reminder plugin
-	reminderPlugin := reminder.New(a.db)
-	plugin.Register(reminderPlugin)
+	plugin.Register(reminder.New(a.db))
+	plugin.Register(domainblock.New())
 
 	// Initialize routes
 	a.initializeRoutes()
@@ -304,20 +303,40 @@ func (a *App) handleMessage(item queue.Item) {
 			continue
 		}
 
-		// Process message
-		responses := p.OnMessage(message, channelPlugin.Config)
+		// Process message and get actions
+		actions := p.OnMessage(message, channelPlugin.Config)
 
-		// Send responses
+		// Get platform for processing actions
 		platform, err := platform.Get(item.Platform)
 		if err != nil {
 			a.logger.Error("Error getting platform", "error", err)
 			continue
 		}
 
-		for _, response := range responses {
-			if err := platform.SendMessage(response); err != nil {
+		// Process each action
+		for _, action := range actions {
+			switch action.Type {
+			case model.ActionSendMessage:
+				// Send a message
+				if action.Message != nil {
+					if err := platform.SendMessage(action.Message); err != nil {
 						a.logger.Error("Error sending message", "error", err)
 					}
+				} else {
+					a.logger.Error("Send message action with nil message")
+				}
+				
+			case model.ActionDeleteMessage:
+				// Delete a message using direct DeleteMessage call
+				if err := platform.DeleteMessage(action.Chat, action.MessageID); err != nil {
+					a.logger.Error("Error deleting message", "error", err, "message_id", action.MessageID)
+				} else {
+					a.logger.Info("Message deleted", "message_id", action.MessageID)
+				}
+				
+			default:
+				a.logger.Error("Unknown action type", "type", action.Type)
+			}
 		}
 	}
 }

internal/db/db.go

@@ -386,6 +386,24 @@ func (d *Database) UpdateChannelPlugin(id int64, enabled bool) error {
 	return err
 }
 
+// UpdateChannelPluginConfig updates a channel plugin's configuration
+func (d *Database) UpdateChannelPluginConfig(id int64, config map[string]interface{}) error {
+	// Convert config to JSON
+	configJSON, err := json.Marshal(config)
+	if err != nil {
+		return err
+	}
+
+	query := `
+		UPDATE channel_plugin
+		SET config = ?
+		WHERE id = ?
+	`
+
+	_, err = d.db.Exec(query, string(configJSON), id)
+	return err
+}
+
 // DeleteChannelPlugin deletes a channel plugin
 func (d *Database) DeleteChannelPlugin(id int64) error {
 	query := `

internal/model/message.go

@@ -4,6 +4,26 @@ import (
 	"time"
 )
 
+// ActionType defines the type of action to perform
+type ActionType string
+
+const (
+	// ActionSendMessage is for sending a message to the chat
+	ActionSendMessage ActionType = "send_message"
+	// ActionDeleteMessage is for deleting a message from the chat
+	ActionDeleteMessage ActionType = "delete_message"
+)
+
+// MessageAction represents an action to be performed on the platform
+type MessageAction struct {
+	Type      ActionType
+	Message   *Message   // For send_message
+	MessageID string     // For delete_message
+	Chat      string     // Chat where the action happens
+	Channel   *Channel   // Channel reference
+	Raw       map[string]interface{} // Additional data for the action
+}
+
 // Message represents a chat message
 type Message struct {
 	Text    string
@@ -75,7 +95,7 @@ type ChannelPlugin struct {
 	ChannelID int64
 	PluginID  string
 	Enabled   bool
-	Config    map[string]interface{}
+	Config    map[string]any
 }
 
 // User represents an admin user

internal/model/platform.go

@@ -43,4 +43,7 @@ type Platform interface {
 
 	// SendMessage sends a message through the platform
 	SendMessage(msg *Message) error
+
+	// DeleteMessage deletes a message from the platform
+	DeleteMessage(channel string, messageID string) error
 }

internal/model/plugin.go

@@ -23,6 +23,6 @@ type Plugin interface {
 	// RequiresConfig indicates if the plugin requires configuration
 	RequiresConfig() bool
 
-	// OnMessage processes an incoming message and returns response messages
-	OnMessage(msg *Message, config map[string]interface{}) []*Message
+	// OnMessage processes an incoming message and returns platform actions
+	OnMessage(msg *Message, config map[string]interface{}) []*MessageAction
 }

internal/platform/slack/slack.go

@@ -167,6 +167,12 @@ func (s *SlackPlatform) SendMessage(msg *model.Message) error {
 		return errors.New("bot token not configured")
 	}
 
+	// Check for delete message action
+	if msg.Raw != nil && msg.Raw["action"] == "delete" {
+		// This is a request to delete a message
+		return s.deleteMessage(msg)
+	}
+
 	// Prepare payload
 	payload := map[string]interface{}{
 		"channel": msg.Chat,
@@ -212,6 +218,63 @@ func (s *SlackPlatform) SendMessage(msg *model.Message) error {
 	return nil
 }
 
+// DeleteMessage deletes a message on Slack
+func (s *SlackPlatform) DeleteMessage(channel string, messageID string) error {
+	// Prepare payload for chat.delete API
+	payload := map[string]interface{}{
+		"channel": channel,
+		"ts":      messageID, // In Slack, the ts (timestamp) is the message ID
+	}
+
+	// Convert payload to JSON
+	data, err := json.Marshal(payload)
+	if err != nil {
+		return err
+	}
+
+	// Send HTTP request to chat.delete endpoint
+	req, err := http.NewRequest("POST", "https://slack.com/api/chat.delete", strings.NewReader(string(data)))
+	if err != nil {
+		return err
+	}
+
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", s.config.BotOAuthAccessToken))
+
+	client := &http.Client{}
+	resp, err := client.Do(req)
+	if err != nil {
+		return err
+	}
+	defer func() {
+		if err := resp.Body.Close(); err != nil {
+			fmt.Printf("Error closing response body: %v\n", err)
+		}
+	}()
+
+	// Check response
+	if resp.StatusCode != http.StatusOK {
+		respBody, _ := io.ReadAll(resp.Body)
+		return fmt.Errorf("slack API error: %d - %s", resp.StatusCode, string(respBody))
+	}
+
+	return nil
+}
+
+// deleteMessage is a legacy method that uses the Raw message approach
+func (s *SlackPlatform) deleteMessage(msg *model.Message) error {
+	// Get message ID to delete
+	messageID, ok := msg.Raw["message_id"]
+	if !ok {
+		return fmt.Errorf("no message ID provided for deletion")
+	}
+	
+	// Convert to string if needed
+	messageIDStr := fmt.Sprintf("%v", messageID)
+	
+	return s.DeleteMessage(msg.Chat, messageIDStr)
+}
+
 // Helper function to parse int64
 func parseInt64(s string) (int64, error) {
 	var n int64

internal/platform/telegram/telegram.go

@@ -217,6 +217,13 @@ func (t *TelegramPlatform) ParseChannelFromMessage(body []byte) (map[string]any,
 
 // SendMessage sends a message to Telegram
 func (t *TelegramPlatform) SendMessage(msg *model.Message) error {
+	// Check for delete message action (legacy method)
+	if msg.Raw != nil && msg.Raw["action"] == "delete" {
+		// This is a request to delete a message using the legacy method
+		return t.deleteMessage(msg)
+	}
+
+	// Regular message sending
 	// Convert chat ID to int64
 	chatID, err := strconv.ParseInt(msg.Chat, 10, 64)
 	if err != nil {
@@ -276,3 +283,88 @@ func (t *TelegramPlatform) SendMessage(msg *model.Message) error {
 	t.log.Debug("Message sent successfully")
 	return nil
 }
+
+// DeleteMessage deletes a message on Telegram
+func (t *TelegramPlatform) DeleteMessage(channel string, messageID string) error {
+	// Convert chat ID to int64
+	chatID, err := strconv.ParseInt(channel, 10, 64)
+	if err != nil {
+		t.log.Error("Invalid chat ID for message deletion", "chat_id", channel, "error", err)
+		return err
+	}
+
+	// Convert message ID to integer
+	msgID, err := strconv.Atoi(messageID)
+	if err != nil {
+		t.log.Error("Invalid message ID for deletion", "message_id", messageID, "error", err)
+		return err
+	}
+
+	// Prepare payload for deleteMessage API
+	payload := map[string]interface{}{
+		"chat_id":    chatID,
+		"message_id": msgID,
+	}
+
+	t.log.Debug("Deleting message on Telegram", "chat_id", chatID, "message_id", msgID)
+
+	// Convert payload to JSON
+	data, err := json.Marshal(payload)
+	if err != nil {
+		t.log.Error("Failed to marshal delete message payload", "error", err)
+		return err
+	}
+
+	// Send HTTP request to deleteMessage endpoint
+	resp, err := http.Post(
+		t.apiURL+"/deleteMessage",
+		"application/json",
+		bytes.NewBuffer(data),
+	)
+	if err != nil {
+		t.log.Error("Failed to delete message", "error", err)
+		return err
+	}
+	defer func() {
+		if err := resp.Body.Close(); err != nil {
+			t.log.Error("Error closing response body", "error", err)
+		}
+	}()
+
+	// Check response
+	if resp.StatusCode != http.StatusOK {
+		bodyBytes, _ := io.ReadAll(resp.Body)
+		errMsg := string(bodyBytes)
+		t.log.Error("Telegram API error when deleting message", "status", resp.StatusCode, "response", errMsg)
+		return fmt.Errorf("telegram API error when deleting message: %d - %s", resp.StatusCode, errMsg)
+	}
+
+	t.log.Debug("Message deleted successfully")
+	return nil
+}
+
+// deleteMessage is a legacy method that uses the Raw message approach
+func (t *TelegramPlatform) deleteMessage(msg *model.Message) error {
+	// Get message ID to delete
+	messageIDInterface, ok := msg.Raw["message_id"]
+	if !ok {
+		t.log.Error("No message ID provided for deletion")
+		return fmt.Errorf("no message ID provided for deletion")
+	}
+
+	// Convert message ID to string
+	var messageIDStr string
+	switch v := messageIDInterface.(type) {
+	case string:
+		messageIDStr = v
+	case int:
+		messageIDStr = strconv.Itoa(v)
+	case float64:
+		messageIDStr = strconv.Itoa(int(v))
+	default:
+		t.log.Error("Invalid message ID type for deletion", "type", fmt.Sprintf("%T", messageIDInterface))
+		return fmt.Errorf("invalid message ID type for deletion")
+	}
+
+	return t.DeleteMessage(msg.Chat, messageIDStr)
+}

internal/plugin/domainblock/domainblock.go

@@ -0,0 +1,132 @@
+package domainblock
+
+import (
+	"fmt"
+	"net/url"
+	"regexp"
+	"strings"
+
+	"git.nakama.town/fmartingr/butterrobot/internal/model"
+	"git.nakama.town/fmartingr/butterrobot/internal/plugin"
+)
+
+// DomainBlockPlugin is a plugin that blocks messages containing links from specific domains
+type DomainBlockPlugin struct {
+	plugin.BasePlugin
+}
+
+// Debug helper to check if RequiresConfig is working
+func (p *DomainBlockPlugin) RequiresConfig() bool {
+	return true
+}
+
+// New creates a new DomainBlockPlugin instance
+func New() *DomainBlockPlugin {
+	return &DomainBlockPlugin{
+		BasePlugin: plugin.BasePlugin{
+			ID:             "security.domainblock",
+			Name:           "Domain Blocker",
+			Help:           "Blocks messages containing links from configured domains",
+			ConfigRequired: true,
+		},
+	}
+}
+
+// extractDomains extracts domains from a message text
+func extractDomains(text string) []string {
+	// URL regex pattern
+	urlPattern := regexp.MustCompile(`https?://([^\s/$.?#].[^\s]*)`)
+	matches := urlPattern.FindAllStringSubmatch(text, -1)
+
+	domains := make([]string, 0, len(matches))
+	for _, match := range matches {
+		if len(match) < 2 {
+			continue
+		}
+
+		// Try to parse the URL to extract the domain
+		urlStr := match[0]
+		parsedURL, err := url.Parse(urlStr)
+		if err != nil {
+			continue
+		}
+
+		// Extract the domain (host) from the URL
+		domain := parsedURL.Host
+		// Remove port if present
+		if i := strings.IndexByte(domain, ':'); i >= 0 {
+			domain = domain[:i]
+		}
+
+		domains = append(domains, strings.ToLower(domain))
+	}
+
+	return domains
+}
+
+// OnMessage processes incoming messages
+func (p *DomainBlockPlugin) OnMessage(msg *model.Message, config map[string]interface{}) []*model.MessageAction {
+	// Skip messages from bots
+	if msg.FromBot {
+		return nil
+	}
+
+	// Get blocked domains from config
+	blockedDomainsStr, ok := config["blocked_domains"].(string)
+	if !ok || blockedDomainsStr == "" {
+		return nil // No blocked domains configured
+	}
+
+	// Split and clean blocked domains
+	blockedDomains := strings.Split(blockedDomainsStr, ",")
+	for i, domain := range blockedDomains {
+		blockedDomains[i] = strings.ToLower(strings.TrimSpace(domain))
+	}
+
+	// Extract domains from message
+	messageDomains := extractDomains(msg.Text)
+	if len(messageDomains) == 0 {
+		return nil // No domains in message
+	}
+
+	// Check if any domains in the message are blocked
+	for _, msgDomain := range messageDomains {
+		for _, blockedDomain := range blockedDomains {
+			if blockedDomain == "" {
+				continue
+			}
+
+			if strings.HasSuffix(msgDomain, blockedDomain) || msgDomain == blockedDomain {
+				// Domain is blocked, create actions
+
+				// 1. Create a delete message action
+				deleteAction := &model.MessageAction{
+					Type:      model.ActionDeleteMessage,
+					MessageID: msg.ID,
+					Chat:      msg.Chat,
+					Channel:   msg.Channel,
+				}
+
+				// 2. Create a notification message action
+				notificationMsg := &model.Message{
+					Text:    fmt.Sprintf("I don't like links from %s 🙈", blockedDomain),
+					Chat:    msg.Chat,
+					Channel: msg.Channel,
+				}
+
+				sendAction := &model.MessageAction{
+					Type:    model.ActionSendMessage,
+					Message: notificationMsg,
+					Chat:    msg.Chat,
+					Channel: msg.Channel,
+				}
+
+				return []*model.MessageAction{deleteAction, sendAction}
+			}
+		}
+	}
+
+	return nil
+}
+
+// Plugin is registered in app.go, not using init()

internal/plugin/domainblock/domainblock_test.go

@@ -0,0 +1,140 @@
+package domainblock
+
+import (
+	"testing"
+
+	"git.nakama.town/fmartingr/butterrobot/internal/model"
+)
+
+func TestExtractDomains(t *testing.T) {
+	tests := []struct {
+		name     string
+		text     string
+		expected []string
+	}{
+		{
+			name:     "No URLs",
+			text:     "Hello, world!",
+			expected: []string{},
+		},
+		{
+			name:     "Single URL",
+			text:     "Check out https://example.com for more info",
+			expected: []string{"example.com"},
+		},
+		{
+			name:     "Multiple URLs",
+			text:     "Check out https://example.com and http://test.example.org for more info",
+			expected: []string{"example.com", "test.example.org"},
+		},
+		{
+			name:     "URL with path",
+			text:     "Check out https://example.com/path/to/resource",
+			expected: []string{"example.com"},
+		},
+		{
+			name:     "URL with port",
+			text:     "Check out https://example.com:8080/path/to/resource",
+			expected: []string{"example.com"},
+		},
+		{
+			name:     "URL with subdomain",
+			text:     "Check out https://sub.example.com",
+			expected: []string{"sub.example.com"},
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			domains := extractDomains(test.text)
+
+			if len(domains) != len(test.expected) {
+				t.Errorf("Expected %d domains, got %d", len(test.expected), len(domains))
+				return
+			}
+
+			for i, domain := range domains {
+				if domain != test.expected[i] {
+					t.Errorf("Expected domain %s, got %s", test.expected[i], domain)
+				}
+			}
+		})
+	}
+}
+
+func TestOnMessage(t *testing.T) {
+	plugin := New()
+
+	tests := []struct {
+		name           string
+		text           string
+		blockedDomains string
+		expectBlocked  bool
+	}{
+		{
+			name:           "No blocked domains",
+			text:           "Check out https://example.com",
+			blockedDomains: "",
+			expectBlocked:  false,
+		},
+		{
+			name:           "No matching domain",
+			text:           "Check out https://example.com",
+			blockedDomains: "bad.com, evil.org",
+			expectBlocked:  false,
+		},
+		{
+			name:           "Matching domain",
+			text:           "Check out https://example.com",
+			blockedDomains: "example.com, evil.org",
+			expectBlocked:  true,
+		},
+		{
+			name:           "Matching subdomain",
+			text:           "Check out https://sub.example.com",
+			blockedDomains: "example.com",
+			expectBlocked:  true,
+		},
+		{
+			name:           "Multiple domains, one matching",
+			text:           "Check out https://example.com and https://good.org",
+			blockedDomains: "bad.com, example.com",
+			expectBlocked:  true,
+		},
+		{
+			name:           "Spaces in blocked domains list",
+			text:           "Check out https://example.com",
+			blockedDomains: "bad.com, example.com , evil.org",
+			expectBlocked:  true,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			msg := &model.Message{
+				Text: test.text,
+				Chat: "test-chat",
+				ID:   "test-id",
+				Channel: &model.Channel{
+					ID: 1,
+				},
+			}
+
+			config := map[string]interface{}{
+				"blocked_domains": test.blockedDomains,
+			}
+
+			responses := plugin.OnMessage(msg, config)
+
+			if test.expectBlocked {
+				if responses == nil || len(responses) == 0 {
+					t.Errorf("Expected message to be blocked, but it wasn't")
+				}
+			} else {
+				if responses != nil && len(responses) > 0 {
+					t.Errorf("Expected message not to be blocked, but it was")
+				}
+			}
+		})
+	}
+}

internal/plugin/fun/coin.go

@@ -29,7 +29,7 @@ func NewCoin() *CoinPlugin {
 }
 
 // OnMessage handles incoming messages
-func (p *CoinPlugin) OnMessage(msg *model.Message, config map[string]interface{}) []*model.Message {
+func (p *CoinPlugin) OnMessage(msg *model.Message, config map[string]interface{}) []*model.MessageAction {
 	if !strings.Contains(strings.ToLower(msg.Text), "flip a coin") {
 		return nil
 	}
@@ -46,5 +46,12 @@ func (p *CoinPlugin) OnMessage(msg *model.Message, config map[string]interface{}
 		Channel: msg.Channel,
 	}
 
-	return []*model.Message{response}
+	action := &model.MessageAction{
+		Type:    model.ActionSendMessage,
+		Message: response,
+		Chat:    msg.Chat,
+		Channel: msg.Channel,
+	}
+
+	return []*model.MessageAction{action}
 }

internal/plugin/fun/dice.go

@@ -32,7 +32,7 @@ func NewDice() *DicePlugin {
 }
 
 // OnMessage handles incoming messages
-func (p *DicePlugin) OnMessage(msg *model.Message, config map[string]interface{}) []*model.Message {
+func (p *DicePlugin) OnMessage(msg *model.Message, config map[string]interface{}) []*model.MessageAction {
 	if !strings.HasPrefix(strings.TrimSpace(strings.ToLower(msg.Text)), "!dice") {
 		return nil
 	}
@@ -62,7 +62,14 @@ func (p *DicePlugin) OnMessage(msg *model.Message, config map[string]interface{}
 		Channel: msg.Channel,
 	}
 
-	return []*model.Message{response}
+	action := &model.MessageAction{
+		Type:    model.ActionSendMessage,
+		Message: response,
+		Chat:    msg.Chat,
+		Channel: msg.Channel,
+	}
+
+	return []*model.MessageAction{action}
 }
 
 // rollDice parses a dice formula string and returns the result

internal/plugin/fun/loquito.go

@@ -24,7 +24,7 @@ func NewLoquito() *LoquitoPlugin {
 }
 
 // OnMessage handles incoming messages
-func (p *LoquitoPlugin) OnMessage(msg *model.Message, config map[string]interface{}) []*model.Message {
+func (p *LoquitoPlugin) OnMessage(msg *model.Message, config map[string]interface{}) []*model.MessageAction {
 	if !strings.Contains(strings.ToLower(msg.Text), "lo quito") {
 		return nil
 	}
@@ -36,5 +36,12 @@ func (p *LoquitoPlugin) OnMessage(msg *model.Message, config map[string]interfac
 		Channel: msg.Channel,
 	}
 
-	return []*model.Message{response}
+	action := &model.MessageAction{
+		Type:    model.ActionSendMessage,
+		Message: response,
+		Chat:    msg.Chat,
+		Channel: msg.Channel,
+	}
+
+	return []*model.MessageAction{action}
 }

internal/plugin/ping/ping.go

@@ -24,11 +24,12 @@ func New() *PingPlugin {
 }
 
 // OnMessage handles incoming messages
-func (p *PingPlugin) OnMessage(msg *model.Message, config map[string]interface{}) []*model.Message {
+func (p *PingPlugin) OnMessage(msg *model.Message, config map[string]interface{}) []*model.MessageAction {
 	if !strings.EqualFold(strings.TrimSpace(msg.Text), "ping") {
 		return nil
 	}
 
+	// Create the response message
 	response := &model.Message{
 		Text:    "pong",
 		Chat:    msg.Chat,
@@ -36,5 +37,13 @@ func (p *PingPlugin) OnMessage(msg *model.Message, config map[string]interface{}
 		Channel: msg.Channel,
 	}
 	
-	return []*model.Message{response}
+	// Create an action to send the message
+	action := &model.MessageAction{
+		Type:    model.ActionSendMessage,
+		Message: response,
+		Chat:    msg.Chat,
+		Channel: msg.Channel,
+	}
+
+	return []*model.MessageAction{action}
 }

internal/plugin/plugin.go

@@ -1,6 +1,7 @@
 package plugin
 
 import (
+	"maps"
 	"sync"
 
 	"git.nakama.town/fmartingr/butterrobot/internal/model"
@@ -41,9 +42,7 @@ func GetAvailablePlugins() map[string]model.Plugin {
 
 	// Create a copy to avoid race conditions
 	result := make(map[string]model.Plugin, len(plugins))
-	for id, plugin := range plugins {
-		result[id] = plugin
-	}
+	maps.Copy(result, plugins)
 
 	return result
 }
@@ -77,6 +76,6 @@ func (p *BasePlugin) RequiresConfig() bool {
 }
 
 // OnMessage is the default implementation that does nothing
-func (p *BasePlugin) OnMessage(msg *model.Message, config map[string]interface{}) []*model.Message {
+func (p *BasePlugin) OnMessage(msg *model.Message, config map[string]interface{}) []*model.MessageAction {
 	return nil
 }

internal/plugin/reminder/reminder.go

@@ -41,7 +41,7 @@ func New(creator ReminderCreator) *Reminder {
 }
 
 // OnMessage processes incoming messages
-func (r *Reminder) OnMessage(msg *model.Message, config map[string]interface{}) []*model.Message {
+func (r *Reminder) OnMessage(msg *model.Message, config map[string]interface{}) []*model.MessageAction {
 	// Only process replies to messages
 	if msg.ReplyTo == "" {
 		return nil
@@ -56,8 +56,7 @@ func (r *Reminder) OnMessage(msg *model.Message, config map[string]interface{})
 	// Parse the duration
 	amount, err := strconv.Atoi(match[1])
 	if err != nil {
-		return []*model.Message{
-			{
+		errorMsg := &model.Message{
 			Text:    "Invalid duration format. Please use a number followed by y (years), mo (months), d (days), h (hours), m (minutes), or s (seconds).",
 			Chat:    msg.Chat,
 			Channel: msg.Channel,
@@ -65,6 +64,14 @@ func (r *Reminder) OnMessage(msg *model.Message, config map[string]interface{})
 			FromBot: true,
 			Date:    time.Now(),
 			ReplyTo: msg.ID,
+		}
+		
+		return []*model.MessageAction{
+			{
+				Type:    model.ActionSendMessage,
+				Message: errorMsg,
+				Chat:    msg.Chat,
+				Channel: msg.Channel,
 			},
 		}
 	}
@@ -86,8 +93,7 @@ func (r *Reminder) OnMessage(msg *model.Message, config map[string]interface{})
 	case "s":
 		duration = time.Duration(amount) * time.Second
 	default:
-		return []*model.Message{
-			{
+		errorMsg := &model.Message{
 			Text:    "Invalid duration unit. Please use y (years), mo (months), d (days), h (hours), m (minutes), or s (seconds).",
 			Chat:    msg.Chat,
 			Channel: msg.Channel,
@@ -95,6 +101,14 @@ func (r *Reminder) OnMessage(msg *model.Message, config map[string]interface{})
 			FromBot: true,
 			Date:    time.Now(),
 			ReplyTo: msg.ID,
+		}
+		
+		return []*model.MessageAction{
+			{
+				Type:    model.ActionSendMessage,
+				Message: errorMsg,
+				Chat:    msg.Chat,
+				Channel: msg.Channel,
 			},
 		}
 	}
@@ -127,8 +141,7 @@ func (r *Reminder) OnMessage(msg *model.Message, config map[string]interface{})
 	)
 
 	if err != nil {
-		return []*model.Message{
-			{
+		errorMsg := &model.Message{
 			Text:    fmt.Sprintf("Failed to create reminder: %v", err),
 			Chat:    msg.Chat,
 			Channel: msg.Channel,
@@ -136,6 +149,14 @@ func (r *Reminder) OnMessage(msg *model.Message, config map[string]interface{})
 			FromBot: true,
 			Date:    time.Now(),
 			ReplyTo: msg.ID,
+		}
+		
+		return []*model.MessageAction{
+			{
+				Type:    model.ActionSendMessage,
+				Message: errorMsg,
+				Chat:    msg.Chat,
+				Channel: msg.Channel,
 			},
 		}
 	}
@@ -157,8 +178,8 @@ func (r *Reminder) OnMessage(msg *model.Message, config map[string]interface{})
 		confirmText = fmt.Sprintf("I'll remind you about this message in %d second(s)", amount)
 	}
 
-	return []*model.Message{
-		{
+	// Create confirmation message
+	confirmMsg := &model.Message{
 		Text:    confirmText,
 		Chat:    msg.Chat,
 		Channel: msg.Channel,
@@ -166,6 +187,14 @@ func (r *Reminder) OnMessage(msg *model.Message, config map[string]interface{})
 		FromBot: true,
 		Date:    time.Now(),
 		ReplyTo: msg.ID,
+	}
+	
+	return []*model.MessageAction{
+		{
+			Type:    model.ActionSendMessage,
+			Message: confirmMsg,
+			Chat:    msg.Chat,
+			Channel: msg.Channel,
 		},
 	}
 }

internal/plugin/reminder/reminder_test.go

@@ -142,14 +142,25 @@ func TestReminderOnMessage(t *testing.T) {
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			initialCount := len(creator.reminders)
-			responses := plugin.OnMessage(tt.message, nil)
+			actions := plugin.OnMessage(tt.message, nil)
 
-			if tt.expectResponse && len(responses) == 0 {
-				t.Errorf("Expected response, but got none")
+			if tt.expectResponse && len(actions) == 0 {
+				t.Errorf("Expected response action, but got none")
 			}
 
-			if !tt.expectResponse && len(responses) > 0 {
-				t.Errorf("Expected no response, but got %d", len(responses))
+			if !tt.expectResponse && len(actions) > 0 {
+				t.Errorf("Expected no actions, but got %d", len(actions))
+			}
+
+			// Verify action type is correct when actions are returned
+			if len(actions) > 0 {
+				if actions[0].Type != model.ActionSendMessage {
+					t.Errorf("Expected action type to be %s, but got %s", model.ActionSendMessage, actions[0].Type)
+				}
+				
+				if actions[0].Message == nil {
+					t.Errorf("Expected message in action to not be nil")
+				}
 			}
 
 			if tt.expectReminder && len(creator.reminders) != initialCount+1 {

internal/plugin/social/instagram.go

@@ -26,7 +26,7 @@ func NewInstagramExpander() *InstagramExpander {
 }
 
 // OnMessage handles incoming messages
-func (p *InstagramExpander) OnMessage(msg *model.Message, config map[string]interface{}) []*model.Message {
+func (p *InstagramExpander) OnMessage(msg *model.Message, config map[string]interface{}) []*model.MessageAction {
 	// Skip empty messages
 	if strings.TrimSpace(msg.Text) == "" {
 		return nil
@@ -70,5 +70,12 @@ func (p *InstagramExpander) OnMessage(msg *model.Message, config map[string]inte
 		Channel: msg.Channel,
 	}
 
-	return []*model.Message{response}
+	action := &model.MessageAction{
+		Type:    model.ActionSendMessage,
+		Message: response,
+		Chat:    msg.Chat,
+		Channel: msg.Channel,
+	}
+
+	return []*model.MessageAction{action}
 }

internal/plugin/social/twitter.go

@@ -26,7 +26,7 @@ func NewTwitterExpander() *TwitterExpander {
 }
 
 // OnMessage handles incoming messages
-func (p *TwitterExpander) OnMessage(msg *model.Message, config map[string]interface{}) []*model.Message {
+func (p *TwitterExpander) OnMessage(msg *model.Message, config map[string]interface{}) []*model.MessageAction {
 	// Skip empty messages
 	if strings.TrimSpace(msg.Text) == "" {
 		return nil
@@ -75,5 +75,12 @@ func (p *TwitterExpander) OnMessage(msg *model.Message, config map[string]interf
 		Channel: msg.Channel,
 	}
 
-	return []*model.Message{response}
+	action := &model.MessageAction{
+		Type:    model.ActionSendMessage,
+		Message: response,
+		Chat:    msg.Chat,
+		Channel: msg.Channel,
+	}
+
+	return []*model.MessageAction{action}
 }