llms/mistral: Implementing embeddings.EmbedderClient for Mistral and an example with PGVector

examples/mistral-embedding-example/go.mod

@@ -0,0 +1,22 @@
+module github.com/tmc/langchaingo/examples/mistral-embedding-example
+
+go 1.22.0
+
+toolchain go1.22.1
+
+require github.com/tmc/langchaingo v0.1.12
+
+replace github.com/tmc/langchaingo => ../../
+
+require (
+	github.com/dlclark/regexp2 v1.10.0 // indirect
+	github.com/gage-technologies/mistral-go v1.1.0 // indirect
+	github.com/google/uuid v1.6.0 // indirect
+	github.com/jackc/pgpassfile v1.0.0 // indirect
+	github.com/jackc/pgservicefile v0.0.0-20221227161230-091c0ba34f0a // indirect
+	github.com/jackc/pgx/v5 v5.5.5 // indirect
+	github.com/pgvector/pgvector-go v0.1.1 // indirect
+	github.com/pkoukk/tiktoken-go v0.1.6 // indirect
+	golang.org/x/crypto v0.23.0 // indirect
+	golang.org/x/text v0.15.0 // indirect
+)

examples/mistral-embedding-example/mistral-embedding-example.go

@@ -0,0 +1,131 @@
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"log"
+	"time"
+
+	"github.com/tmc/langchaingo/embeddings"
+	"github.com/tmc/langchaingo/llms/mistral"
+	"github.com/tmc/langchaingo/schema"
+	"github.com/tmc/langchaingo/vectorstores"
+	"github.com/tmc/langchaingo/vectorstores/pgvector"
+)
+
+func main() {
+	var dsn string
+	flag.StringVar(&dsn, "dsn", "", "PGvector connection string")
+	flag.Parse()
+	model, err := mistral.New()
+	if err != nil {
+		panic(err)
+	}
+
+	e, err := embeddings.NewEmbedder(model)
+
+	if err != nil {
+		panic(err)
+	}
+
+	// Create a new pgvector store.
+	ctx := context.Background()
+	store, err := pgvector.New(
+		ctx,
+		pgvector.WithConnectionURL(dsn),
+		pgvector.WithEmbedder(e),
+	)
+	if err != nil {
+		log.Fatal("pgvector.New", err)
+	}
+
+	// Add documents to the pgvector store.
+	_, err = store.AddDocuments(context.Background(), []schema.Document{
+		{
+			PageContent: "Tokyo",
+			Metadata: map[string]any{
+				"population": 38,
+				"area":       2190,
+			},
+		},
+		{
+			PageContent: "Paris",
+			Metadata: map[string]any{
+				"population": 11,
+				"area":       105,
+			},
+		},
+		{
+			PageContent: "London",
+			Metadata: map[string]any{
+				"population": 9.5,
+				"area":       1572,
+			},
+		},
+		{
+			PageContent: "Santiago",
+			Metadata: map[string]any{
+				"population": 6.9,
+				"area":       641,
+			},
+		},
+		{
+			PageContent: "Buenos Aires",
+			Metadata: map[string]any{
+				"population": 15.5,
+				"area":       203,
+			},
+		},
+		{
+			PageContent: "Rio de Janeiro",
+			Metadata: map[string]any{
+				"population": 13.7,
+				"area":       1200,
+			},
+		},
+		{
+			PageContent: "Sao Paulo",
+			Metadata: map[string]any{
+				"population": 22.6,
+				"area":       1523,
+			},
+		},
+	})
+	if err != nil {
+		log.Fatal("store.AddDocuments:\n", err)
+	}
+	time.Sleep(1 * time.Second)
+
+	// Search for similar documents.
+	docs, err := store.SimilaritySearch(ctx, "japan", 1)
+	if err != nil {
+		log.Fatal("store.SimilaritySearch1:\n", err)
+	}
+	fmt.Println("store.SimilaritySearch1:\n", docs)
+
+	time.Sleep(2 * time.Second) // Don't trigger cloudflare
+
+	// Search for similar documents using score threshold.
+	docs, err = store.SimilaritySearch(ctx, "only cities in south america", 3, vectorstores.WithScoreThreshold(0.50))
+	if err != nil {
+		log.Fatal("store.SimilaritySearch2:\n", err)
+	}
+	fmt.Println("store.SimilaritySearch2:\n", docs)
+
+	time.Sleep(3 * time.Second) // Don't trigger cloudflare
+
+	// Search for similar documents using score threshold and metadata filter.
+	// Metadata filter for pgvector only supports key-value pairs for now.
+	filter := map[string]any{"area": "1523"} // Sao Paulo
+
+	docs, err = store.SimilaritySearch(ctx, "only cities in south america",
+		3,
+		vectorstores.WithScoreThreshold(0.50),
+		vectorstores.WithFilters(filter),
+	)
+	if err != nil {
+		log.Fatal("store.SimilaritySearch3:\n", err)
+	}
+	fmt.Println("store.SimilaritySearch3:\n", docs)
+}

go.mod

@@ -158,7 +158,6 @@ require (
 	gitlab.com/golang-commonmark/linkify v0.0.0-20191026162114-a0c2df6c8f82 // indirect
 	gitlab.com/golang-commonmark/mdurl v0.0.0-20191124015652-932350d1cb84 // indirect
 	gitlab.com/golang-commonmark/puny v0.0.0-20191124015043-9f83538fa04f // indirect
-	go.mongodb.org/mongo-driver/v2 v2.0.0-beta1 // indirect
 	go.opencensus.io v0.24.0 // indirect
 	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.51.0 // indirect
 	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.51.0 // indirect
@@ -196,7 +195,7 @@ require (
 	github.com/aws/aws-sdk-go-v2/service/bedrockruntime v1.8.1
 	github.com/cohere-ai/tokenizer v1.1.2
 	github.com/fatih/color v1.17.0
-	github.com/gage-technologies/mistral-go v1.0.0
+	github.com/gage-technologies/mistral-go v1.1.0
 	github.com/getzep/zep-go v1.0.4
 	github.com/go-openapi/strfmt v0.21.3
 	github.com/go-sql-driver/mysql v1.7.1
@@ -220,6 +219,7 @@ require (
 	github.com/weaviate/weaviate-go-client/v4 v4.13.1
 	gitlab.com/golang-commonmark/markdown v0.0.0-20211110145824-bf3e522c626a
 	go.mongodb.org/mongo-driver v1.14.0
+	go.mongodb.org/mongo-driver/v2 v2.0.0-beta1
 	go.starlark.net v0.0.0-20230302034142-4b1e35fe2254
 	golang.org/x/exp v0.0.0-20230713183714-613f0c0eb8a1
 	golang.org/x/tools v0.14.0

go.sum

@@ -196,8 +196,8 @@ github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSw
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/gabriel-vasile/mimetype v1.4.2 h1:w5qFW6JKBz9Y393Y4q372O9A7cUSequkh1Q7OhCmWKU=
 github.com/gabriel-vasile/mimetype v1.4.2/go.mod h1:zApsH/mKG4w07erKIaJPFiX0Tsq9BFQgN3qGY5GnNgA=
-github.com/gage-technologies/mistral-go v1.0.0 h1:Hwk0uJO+Iq4kMX/EwbfGRUq9zkO36w7HZ/g53N4N73A=
-github.com/gage-technologies/mistral-go v1.0.0/go.mod h1:tF++Xt7U975GcLlzhrjSQb8l/x+PrriO9QEdsgm9l28=
+github.com/gage-technologies/mistral-go v1.1.0 h1:POv1wM9jA/9OBXGV2YdPi9Y/h09+MjCbUF+9hRYlVUI=
+github.com/gage-technologies/mistral-go v1.1.0/go.mod h1:tF++Xt7U975GcLlzhrjSQb8l/x+PrriO9QEdsgm9l28=
 github.com/gavv/httpexpect v2.0.0+incompatible/go.mod h1:x+9tiU1YnrOvnB725RkpoLv1M62hOWzwo5OXotisrKc=
 github.com/getsentry/raven-go v0.2.0/go.mod h1:KungGk8q33+aIAZUIVWZDr2OfAEBsO49PX4NzFV5kcQ=
 github.com/getsentry/sentry-go v0.12.0 h1:era7g0re5iY13bHSdN/xMkyV+5zZppjRVQhZrXCaEIk=

llms/mistral/mistralembed.go

@@ -0,0 +1,36 @@
+package mistral
+
+import (
+	"context"
+	"errors"
+)
+
+var ErrEmptyEmbeddings = errors.New("empty embeddings")
+
+func convertFloat64ToFloat32(input []float64) []float32 {
+	// Create a slice with the same length as the input.
+	output := make([]float32, len(input))
+
+	// Iterate over the input slice and convert each element.
+	for i, v := range input {
+		output[i] = float32(v)
+	}
+
+	return output
+}
+
+// CreateEmbedding implements the embeddings.EmbedderClient interface and creates embeddings for the given input texts.
+func (m *Model) CreateEmbedding(_ context.Context, inputTexts []string) ([][]float32, error) {
+	embsRes, err := m.client.Embeddings("mistral-embed", inputTexts)
+	if err != nil {
+		return nil, errors.New("failed to create embeddings: " + err.Error())
+	}
+	allEmbds := make([][]float32, len(embsRes.Data))
+	for i, embs := range embsRes.Data {
+		if len(embs.Embedding) == 0 {
+			return nil, ErrEmptyEmbeddings
+		}
+		allEmbds[i] = convertFloat64ToFloat32(embs.Embedding)
+	}
+	return allEmbds, nil
+}

llms/mistral/mistralembed_test.go

@@ -0,0 +1,79 @@
+package mistral
+
+import (
+	"context"
+	"os"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"github.com/tmc/langchaingo/embeddings"
+)
+
+// TestConvertFloat64ToFloat32 tests the ConvertFloat64ToFloat32 function using table-driven tests.
+func TestConvertFloat64ToFloat32(t *testing.T) {
+	t.Parallel()
+	tests := []struct {
+		name     string
+		input    []float64
+		expected []float32
+	}{
+		{
+			name:     "empty slice",
+			input:    []float64{},
+			expected: []float32{},
+		},
+		{
+			name:     "single element",
+			input:    []float64{3.14},
+			expected: []float32{3.14},
+		},
+		{
+			name:     "multiple elements",
+			input:    []float64{1.23, 4.56, 7.89},
+			expected: []float32{1.23, 4.56, 7.89},
+		},
+		{
+			name:     "zero values",
+			input:    []float64{0.0, 0.0, 0.0},
+			expected: []float32{0.0, 0.0, 0.0},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			output := convertFloat64ToFloat32(tt.input)
+
+			require.Equal(t, len(tt.expected), len(output), "length mismatch")
+			for i := range output {
+				require.Equal(t, tt.expected[i], output[i], "at index %d", i)
+			}
+		})
+	}
+}
+
+func TestMistralEmbed(t *testing.T) {
+	t.Parallel()
+	envVar := "MISTRAL_API_KEY"
+
+	// Get the value of the environment variable
+	value := os.Getenv(envVar)
+
+	// Check if it is set (non-empty)
+	if value == "" {
+		t.Skipf("Environment variable %s is not set, so skipping the test", envVar)
+		return
+	}
+
+	model, err := New()
+	require.NoError(t, err)
+
+	e, err := embeddings.NewEmbedder(model)
+	require.NoError(t, err)
+
+	_, err = e.EmbedDocuments(context.Background(), []string{"Hello world"})
+	require.NoError(t, err)
+
+	_, err = e.EmbedQuery(context.Background(), "Hello world")
+	require.NoError(t, err)
+}