ollama: Fix JSON format bug issue when not streaming (#892)

* Graceful handling when LLM spits whitespace on json mode with Ollama.

* ollama: Simplify stream repr, spruce up fn calling example

---------

Co-authored-by: Travis Cline <[email protected]>

Author: doslindos

examples/ollama-functions-example/ollama_functions_example.go

@@ -3,6 +3,7 @@ package main
 import (
 	"context"
 	"encoding/json"
+	"flag"
 	"fmt"
 	"log"
 	"os"
@@ -12,10 +13,13 @@ import (
 	"github.com/tmc/langchaingo/llms/ollama"
 )
 
+var flagVerbose = flag.Bool("v", false, "verbose mode")
+
 func main() {
+	flag.Parse()
 	// allow specifying your own model via OLLAMA_TEST_MODEL
 	// (same as the Ollama unit tests).
-	model := "mistral:instruct"
+	model := "llama3"
 	if v := os.Getenv("OLLAMA_TEST_MODEL"); v != "" {
 		model = v
 	}
@@ -31,14 +35,12 @@ func main() {
 	var msgs []llms.MessageContent
 
 	// system message defines the available tools.
-	msgs = append(msgs, llms.TextParts(llms.ChatMessageTypeSystem,
-		systemMessage()))
-	msgs = append(msgs, llms.TextParts(llms.ChatMessageTypeHuman,
-		"What's the weather like in Beijing?"))
+	msgs = append(msgs, llms.TextParts(llms.ChatMessageTypeSystem, systemMessage()))
+	msgs = append(msgs, llms.TextParts(llms.ChatMessageTypeHuman, "What's the weather like in Beijing?"))
 
 	ctx := context.Background()
 
-	for {
+	for retries := 3; retries > 0; retries = retries - 1 {
 		resp, err := llm.GenerateContent(ctx, msgs)
 		if err != nil {
 			log.Fatal(err)
@@ -49,19 +51,23 @@ func main() {
 
 		if c := unmarshalCall(choice1.Content); c != nil {
 			log.Printf("Call: %v", c.Tool)
-
+			if *flagVerbose {
+				log.Printf("Call: %v (raw: %v)", c.Tool, choice1.Content)
+			}
 			msg, cont := dispatchCall(c)
 			if !cont {
 				break
 			}
-
 			msgs = append(msgs, msg)
 		} else {
 			// Ollama doesn't always respond with a function call, let it try again.
 			log.Printf("Not a call: %v", choice1.Content)
-
 			msgs = append(msgs, llms.TextParts(llms.ChatMessageTypeHuman, "Sorry, I don't understand. Please try again."))
 		}
+
+		if retries == 0 {
+			log.Fatal("retries exhausted")
+		}
 	}
 }
 
@@ -72,20 +78,17 @@ type Call struct {
 
 func unmarshalCall(input string) *Call {
 	var c Call
-
 	if err := json.Unmarshal([]byte(input), &c); err == nil && c.Tool != "" {
 		return &c
 	}
-
 	return nil
 }
 
 func dispatchCall(c *Call) (llms.MessageContent, bool) {
 	// ollama doesn't always respond with a *valid* function call. As we're using prompt
 	// engineering to inject the tools, it may hallucinate.
 	if !validTool(c.Tool) {
-		log.Printf("invalid function call: %#v", c)
-
+		log.Printf("invalid function call: %#v, prompting model to try again", c)
 		return llms.TextParts(llms.ChatMessageTypeHuman,
 			"Tool does not exist, please try again."), true
 	}
@@ -106,7 +109,7 @@ func dispatchCall(c *Call) (llms.MessageContent, bool) {
 		if err != nil {
 			log.Fatal(err)
 		}
-		return llms.TextParts(llms.ChatMessageTypeSystem, weather), true
+		return llms.TextParts(llms.ChatMessageTypeHuman, weather), true
 	case "finalResponse":
 		resp, ok := c.Input["response"].(string)
 		if !ok {
@@ -124,11 +127,9 @@ func dispatchCall(c *Call) (llms.MessageContent, bool) {
 
 func validTool(name string) bool {
 	var valid []string
-
 	for _, v := range functions {
 		valid = append(valid, v.Name)
 	}
-
 	return slices.Contains(valid, name)
 }
 

llms/ollama/internal/ollamaclient/types.go

@@ -49,7 +49,7 @@ type Message struct {
 type ChatRequest struct {
 	Model     string     `json:"model"`
 	Messages  []*Message `json:"messages"`
-	Stream    *bool      `json:"stream,omitempty"`
+	Stream    bool       `json:"stream,omitempty"`
 	Format    string     `json:"format"`
 	KeepAlive string     `json:"keep_alive,omitempty"`
 

llms/ollama/ollamallm.go

@@ -108,7 +108,7 @@ func (o *LLM) GenerateContent(ctx context.Context, messages []llms.MessageConten
 		Format:   format,
 		Messages: chatMsgs,
 		Options:  ollamaOptions,
-		Stream:   func(b bool) *bool { return &b }(opts.StreamingFunc != nil),
+		Stream:   opts.StreamingFunc != nil,
 	}
 
 	keepAlive := o.options.keepAlive
@@ -129,7 +129,7 @@ func (o *LLM) GenerateContent(ctx context.Context, messages []llms.MessageConten
 		if response.Message != nil {
 			streamedResponse += response.Message.Content
 		}
-		if response.Done {
+		if !req.Stream || response.Done {
 			resp = response
 			resp.Message = &ollamaclient.Message{
 				Role:    "assistant",