add open AI spam filter

app/bot/openai/openai.go

@@ -304,3 +304,8 @@ func (o *OpenAI) Summary(text string) (response string, err error) {
 func (o *OpenAI) ReactOn() []string {
 	return []string{"chat!", "gpt!", "ai!", "чат!"}
 }
+
+// CreateChatCompletion exposes the underlying openai.CreateChatCompletion method
+func (o *OpenAI) CreateChatCompletion(ctx context.Context, req openai.ChatCompletionRequest) (openai.ChatCompletionResponse, error) {
+	return o.client.CreateChatCompletion(ctx, req)
+}

app/bot/spam_openai.go

@@ -0,0 +1,117 @@
+package bot
+
+import (
+	"bufio"
+	"context"
+	"fmt"
+	"io"
+	"log"
+	"strings"
+
+	"github.com/sashabaranov/go-openai"
+)
+
+//go:generate moq --out mocks/openai_client.go --pkg mocks --skip-ensure . OpenAIClient
+
+// SpamOpenAIFilter bot, checks if user is a spammer using openai api call
+type SpamOpenAIFilter struct {
+	dry       bool
+	superUser SuperUser
+	openai    OpenAIClient
+	maxLen    int
+
+	spamPrompt    string
+	enabled       bool
+	approvedUsers map[int64]bool
+}
+
+// OpenAIClient is interface for OpenAI client with the possibility to mock it
+type OpenAIClient interface {
+	CreateChatCompletion(context.Context, openai.ChatCompletionRequest) (openai.ChatCompletionResponse, error)
+}
+
+// NewSpamOpenAIFilter makes a spam detecting bot
+func NewSpamOpenAIFilter(spamSamples io.Reader, openai OpenAIClient, maxLen int, superUser SuperUser, dry bool) *SpamOpenAIFilter {
+	log.Printf("[INFO] Spam bot (openai)")
+	res := &SpamOpenAIFilter{dry: dry, approvedUsers: map[int64]bool{}, superUser: superUser, openai: openai}
+
+	scanner := bufio.NewScanner(spamSamples)
+	for scanner.Scan() {
+		res.spamPrompt += scanner.Text() + "\n"
+	}
+	if err := scanner.Err(); err != nil {
+		log.Printf("[WARN] failed to read spam samples, error=%v", err)
+		res.enabled = false
+	} else {
+		res.enabled = true
+	}
+	if len(res.spamPrompt) > maxLen {
+		res.spamPrompt = res.spamPrompt[:maxLen]
+	}
+	return res
+}
+
+// OnMessage checks if user already approved and if not checks if user is a spammer
+func (s *SpamOpenAIFilter) OnMessage(msg Message) (response Response) {
+	if s.approvedUsers[msg.From.ID] {
+		return Response{}
+	}
+
+	if s.superUser.IsSuper(msg.From.Username) {
+		return Response{} // don't check super users for spam
+	}
+
+	if !s.isSpam(msg.Text) {
+		log.Printf("[INFO] user %s (%d) is not a spammer, added to aproved", msg.From.Username, msg.From.ID)
+		s.approvedUsers[msg.From.ID] = true
+		return Response{} // not a spam
+	}
+
+	log.Printf("[INFO] user %s detected as spammer, msg: %q", msg.From.Username, msg.Text)
+	if s.dry {
+		return Response{
+			Text: fmt.Sprintf("this is spam from %q, but I'm in dry mode, so I'll do nothing yet", msg.From.Username),
+			Send: true, ReplyTo: msg.ID,
+		}
+	}
+	return Response{Text: "this is spam! go to ban, " + msg.From.DisplayName, Send: true, ReplyTo: msg.ID, BanInterval: permanentBanDuration, DeleteReplyTo: true}
+}
+
+// Help returns help message
+func (s *SpamOpenAIFilter) Help() string { return "" }
+
+// ReactOn keys
+func (s *SpamOpenAIFilter) ReactOn() []string { return []string{} }
+
+// isSpam checks if a given message is similar to any of the known bad messages.
+func (s *SpamOpenAIFilter) isSpam(message string) bool {
+
+	messages := []openai.ChatCompletionMessage{}
+	messages = append(messages, openai.ChatCompletionMessage{
+		Role:    openai.ChatMessageRoleSystem,
+		Content: "this is the list of spam messages. I will give you a messages to detect if this is spam or not and you will answer with a single world \"OK\" or \"SPAM\"\n\n" + s.spamPrompt,
+	})
+	messages = append(messages, openai.ChatCompletionMessage{
+		Role:    openai.ChatMessageRoleUser,
+		Content: message,
+	})
+
+	resp, err := s.openai.CreateChatCompletion(
+		context.Background(),
+		openai.ChatCompletionRequest{
+			Model:     openai.GPT3Dot5Turbo,
+			MaxTokens: 1024,
+			Messages:  messages,
+		},
+	)
+	if err != nil {
+		log.Printf("[WARN] failed to check spam, error=%v", err)
+		return false
+	}
+	if len(resp.Choices) == 0 {
+		log.Printf("[WARN] empty response from openai")
+		return false
+	}
+
+	return strings.Contains(resp.Choices[0].Message.Content, "SPAM")
+}

app/bot/spam_openai_test.go

@@ -0,0 +1,83 @@
+package bot
+
+import (
+	"context"
+	"strings"
+	"testing"
+
+	"github.com/sashabaranov/go-openai"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/radio-t/super-bot/app/bot/mocks"
+)
+
+func TestSpamOpenAIFilter_isSpam(t *testing.T) {
+	spamSamples := strings.NewReader("spam1\nspam2\nspam3")
+	mockOpenAI := &mocks.OpenAIClientMock{}
+
+	filter := NewSpamOpenAIFilter(spamSamples, mockOpenAI, 4096, nil, false)
+	require.True(t, filter.enabled)
+	assert.True(t, len(filter.spamPrompt) <= 4096)
+
+	mockOpenAI.CreateChatCompletionFunc = func(ctx context.Context, req openai.ChatCompletionRequest) (openai.ChatCompletionResponse, error) {
+		return openai.ChatCompletionResponse{
+			Choices: []openai.ChatCompletionChoice{
+				{
+					Message: openai.ChatCompletionMessage{
+						Content: "SPAM",
+					},
+				},
+			},
+		}, nil
+	}
+
+	assert.True(t, filter.isSpam("this is a spam message"))
+	assert.Equal(t, 1, len(mockOpenAI.CreateChatCompletionCalls()))
+
+	mockOpenAI.CreateChatCompletionFunc = func(ctx context.Context, req openai.ChatCompletionRequest) (openai.ChatCompletionResponse, error) {
+		return openai.ChatCompletionResponse{
+			Choices: []openai.ChatCompletionChoice{
+				{
+					Message: openai.ChatCompletionMessage{
+						Content: "OK",
+					},
+				},
+			},
+		}, nil
+	}
+
+	assert.False(t, filter.isSpam("this is not a spam message"))
+	assert.Equal(t, 2, len(mockOpenAI.CreateChatCompletionCalls()))
+}
+
+func TestSpamOpenAIFilter_OnMessage(t *testing.T) {
+	superUser := &mocks.SuperUser{IsSuperFunc: func(userName string) bool {
+		if userName == "super" || userName == "admin" {
+			return true
+		}
+		return false
+	}}
+
+	spamSamples := strings.NewReader("spam1\nspam2\nspam3")
+	mockOpenAI := &mocks.OpenAIClientMock{
+		CreateChatCompletionFunc: func(ctx context.Context, req openai.ChatCompletionRequest) (openai.ChatCompletionResponse, error) {
+			return openai.ChatCompletionResponse{
+				Choices: []openai.ChatCompletionChoice{
+					{
+						Message: openai.ChatCompletionMessage{
+							Content: "OK",
+						},
+					},
+				},
+			}, nil
+		},
+	}
+
+	filter := NewSpamOpenAIFilter(spamSamples, mockOpenAI, 4096, superUser, false)
+
+	msg := Message{From: User{ID: 1, Username: "user1"}, Text: "hello"}
+	resp := filter.OnMessage(msg)
+
+	assert.Empty(t, resp.Text)
+}

app/main.go

@@ -154,6 +154,8 @@ func main() {
 			}
 			multiBot = append(multiBot, bot.NewSpamLocalFilter(spamFh, opts.SpamFilter.Threshold,
 				opts.SuperUsers, opts.SpamFilter.Dry))
+			multiBot = append(multiBot, bot.NewSpamOpenAIFilter(spamFh, openAIBot, opts.OpenAI.MaxSymbolsRequest,
+				opts.SuperUsers, opts.SpamFilter.Dry))
 		}
 	} else {
 		log.Print("[INFO] spam filter disabled")