Merge branch 'main' into docs_site_preview_in_ci

.github/FUNDING.yml

@@ -0,0 +1,2 @@
+# These are supported funding model platforms
+github: tmc

.github/workflows/ci.yaml

@@ -44,4 +44,7 @@ jobs:
       - name: Build
         run: go build -v ./...
       - name: Test
+        env:
+          OPENAI_API_KEY: ${{ secrets.OPENAI_API_KEY }}
+          GENAI_API_KEY: ${{ secrets.GENAI_API_KEY }}
         run: go test -v ./...

README.md

@@ -58,6 +58,7 @@ Socktastic
 
 Here are some links to blog posts and articles on using Langchain Go:
 
+- [Using Gemini models in Go with LangChainGo](https://eli.thegreenplace.net/2024/using-gemini-models-in-go-with-langchaingo/) - Jan 2024
 - [Using Ollama with LangChainGo](https://eli.thegreenplace.net/2023/using-ollama-with-langchaingo/) - Nov 2023
 - [Creating a simple ChatGPT clone with Go](https://sausheong.com/creating-a-simple-chatgpt-clone-with-go-c40b4bec9267?sk=53a2bcf4ce3b0cfae1a4c26897c0deb0) - Aug 2023
 - [Creating a ChatGPT Clone that Runs on Your Laptop with Go](https://sausheong.com/creating-a-chatgpt-clone-that-runs-on-your-laptop-with-go-bf9d41f1cf88?sk=05dc67b60fdac6effb1aca84dd2d654e) - Aug 2023

agents/mrkl_prompt.go

@@ -9,8 +9,8 @@ import (
 )
 
 const (
-	_defaultMrklPrefix = `Today is {{.today}} and you can use tools to get new information.
-Answer the following questions as best you can using the following tools:
+	_defaultMrklPrefix = `Today is {{.today}}.
+Answer the following questions as best you can. You have access to the following tools:
 
 {{.tool_descriptions}}`
 

callbacks/agent_final_stream.go

@@ -76,28 +76,32 @@ func (handler *AgentFinalStreamHandler) ReadFromEgress(
 func (handler *AgentFinalStreamHandler) HandleStreamingFunc(_ context.Context, chunk []byte) {
 	chunkStr := string(chunk)
 	handler.LastTokens += chunkStr
+	var detectedKeyword string
 
 	// Buffer the last few chunks to match the longest keyword size
-	longestSize := len(handler.Keywords[0])
+	var longestSize int
 	for _, k := range handler.Keywords {
 		if len(k) > longestSize {
 			longestSize = len(k)
 		}
 	}
 
-	if len(handler.LastTokens) > longestSize {
-		handler.LastTokens = handler.LastTokens[len(handler.LastTokens)-longestSize:]
-	}
-
 	// Check for keywords
 	for _, k := range DefaultKeywords {
 		if strings.Contains(handler.LastTokens, k) {
 			handler.KeywordDetected = true
+			detectedKeyword = k
 		}
 	}
 
+	if len(handler.LastTokens) > longestSize {
+		handler.LastTokens = handler.LastTokens[len(handler.LastTokens)-longestSize:]
+	}
+
 	// Check for colon and set print mode.
-	if handler.KeywordDetected && chunkStr != ":" {
+	if handler.KeywordDetected && !handler.PrintOutput {
+		// remove any other strings before the final answer
+		chunk = []byte(filterFinalString(chunkStr, detectedKeyword))
 		handler.PrintOutput = true
 	}
 
@@ -106,3 +110,17 @@ func (handler *AgentFinalStreamHandler) HandleStreamingFunc(_ context.Context, c
 		handler.egress <- chunk
 	}
 }
+
+func filterFinalString(chunkStr, keyword string) string {
+	chunkStr = strings.TrimLeft(chunkStr, " ")
+
+	index := strings.Index(chunkStr, keyword)
+	switch {
+	case index != -1:
+		chunkStr = chunkStr[index+len(keyword):]
+	case strings.HasPrefix(chunkStr, ":"):
+		chunkStr = strings.TrimPrefix(chunkStr, ":")
+	}
+
+	return strings.TrimLeft(chunkStr, " ")
+}

callbacks/agent_final_stream_test.go

@@ -0,0 +1,53 @@
+package callbacks
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestFilterFinalString(t *testing.T) {
+	t.Parallel()
+
+	cases := []struct {
+		keyword  string
+		inputStr string
+		expected string
+	}{
+		{
+			keyword:  "Final Answer:",
+			inputStr: "This is a correct final string.",
+			expected: "This is a correct final string.",
+		},
+		{
+			keyword:  "Final Answer:",
+			inputStr: " some other text above.\nFinal Answer: This is a correct final string.",
+			expected: "This is a correct final string.",
+		},
+		{
+			keyword:  "Final Answer:",
+			inputStr: " another text before. Final Answer: This is a correct final string.",
+			expected: "This is a correct final string.",
+		},
+		{
+			keyword:  "Final Answer:",
+			inputStr: `   :    This is a correct final string.`,
+			expected: "This is a correct final string.",
+		},
+		{
+			keyword:  "Customed KeyWord_2:",
+			inputStr: " some other text above.\nSome Customed KeyWord_2: This is a correct final string.",
+			expected: "This is a correct final string.",
+		},
+		{
+			keyword:  "Customed KeyWord_$#@-123:",
+			inputStr: " another text before keyword. Some Customed KeyWord_$#@-123: This is a correct final string.",
+			expected: "This is a correct final string.",
+		},
+	}
+
+	for _, tc := range cases {
+		filteredStr := filterFinalString(tc.inputStr, tc.keyword)
+		require.Equal(t, tc.expected, filteredStr)
+	}
+}

chains/api_test.go

@@ -66,5 +66,5 @@ func TestAPI(t *testing.T) {
 	if !ok {
 		t.Fatal("expected answer to be a string")
 	}
-	require.True(t, strings.Contains(answer, "temperature"), `result does not contain the keyword 'temperature'`)
+	require.True(t, strings.Contains(answer, "Munich"), `result does not contain the keyword 'Munich'`)
 }

chains/chains.go

@@ -87,8 +87,8 @@ func callChain(
 	return outputValues, nil
 }
 
-// Run can be used to execute a chain if the chain only expects one input and one
-// string output.
+// Run can be used to execute a chain if the chain only expects one input and
+// one string output.
 func Run(ctx context.Context, c Chain, input any, options ...ChainCallOption) (string, error) {
 	inputKeys := c.GetInputKeys()
 	memoryKeys := c.GetMemory().MemoryVariables(ctx)

chains/llm_math.go

@@ -33,8 +33,7 @@ func NewLLMMathChain(llm llms.Model) LLMMathChain {
 	}
 }
 
-// Call gets relevant documents from the retriever and gives them to the combine
-// documents chain.
+// Call runs the logic of the LLM Math chain and returns the output.
 func (c LLMMathChain) Call(ctx context.Context, values map[string]any, options ...ChainCallOption) (map[string]any, error) { // nolint: lll
 	question, ok := values["question"].(string)
 	if !ok {
@@ -71,7 +70,7 @@ func (c LLMMathChain) processLLMResult(llmOutput string) (string, error) {
 		expression := textMatch[1]
 		output, err := c.evaluateExpression(expression)
 		if err != nil {
-			return "", err
+			return "", fmt.Errorf("evaluating expression: %w", err)
 		}
 		return output, nil
 	}

chains/llm_test.go

@@ -8,6 +8,7 @@ import (
 
 	"github.com/stretchr/testify/require"
 	"github.com/tmc/langchaingo/callbacks"
+	"github.com/tmc/langchaingo/llms/googleai"
 	"github.com/tmc/langchaingo/llms/openai"
 	"github.com/tmc/langchaingo/prompts"
 )
@@ -55,3 +56,35 @@ func TestLLMChainWithChatPromptTemplate(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, "AI: foo\nHuman: boo", result)
 }
+
+func TestLLMChainWithGoogleAI(t *testing.T) {
+	t.Parallel()
+	genaiKey := os.Getenv("GENAI_API_KEY")
+	if genaiKey == "" {
+		t.Skip("GENAI_API_KEY not set")
+	}
+	model, err := googleai.New(context.Background(), googleai.WithAPIKey(genaiKey))
+	require.NoError(t, err)
+	require.NoError(t, err)
+	model.CallbacksHandler = callbacks.LogHandler{}
+
+	prompt := prompts.NewPromptTemplate(
+		"What is the capital of {{.country}}",
+		[]string{"country"},
+	)
+	require.NoError(t, err)
+
+	chain := NewLLMChain(model, prompt)
+
+	// chains tramples over defaults for options, so setting these options
+	// explicitly is required until https://github.com/tmc/langchaingo/issues/626
+	// is fully resolved.
+	result, err := Predict(context.Background(), chain,
+		map[string]any{
+			"country": "France",
+		},
+		WithCallback(callbacks.LogHandler{}),
+	)
+	require.NoError(t, err)
+	require.True(t, strings.Contains(result, "Paris"))
+}