feat: Added Qdrant vectorstore support

vectorstores/qdrant/doc.go

@@ -0,0 +1,3 @@
+// Package qdrant contains an implementation of the VectorStore
+// interface using Qdrant.
+package qdrant

vectorstores/qdrant/options.go

@@ -0,0 +1,81 @@
+package qdrant
+
+import (
+	"errors"
+	"fmt"
+	"net/url"
+
+	"github.com/tmc/langchaingo/embeddings"
+)
+
+const (
+	defaultContentKey = "content"
+)
+
+// ErrInvalidOptions is returned when the options given are invalid.
+var ErrInvalidOptions = errors.New("invalid options")
+
+// Option is a function that configures an Options.
+type Option func(p *Store)
+
+// WithCollectionName returns an Option for setting the collection name. Required.
+func WithCollectionName(name string) Option {
+	return func(p *Store) {
+		p.collectionName = name
+	}
+}
+
+// WithURL returns an Option for setting the Qdrant instance URL.
+// Example: 'http://localhost:63333'. Required.
+func WithURL(qdrantURL url.URL) Option {
+	return func(p *Store) {
+		p.qdrantURL = qdrantURL
+	}
+}
+
+// WithEmbedder returns an Option for setting the embedder to be used when
+// adding documents or doing similarity search. Required.
+func WithEmbedder(embedder embeddings.Embedder) Option {
+	return func(p *Store) {
+		p.embedder = embedder
+	}
+}
+
+// WithAPIKey returns an Option for setting the API key to authenticate the connection. Optional.
+func WithAPIKey(apiKey string) Option {
+	return func(p *Store) {
+		p.apiKey = apiKey
+	}
+}
+
+// WithContent returns an Option for setting field name of the document content
+// in the Qdrant payload. Optional. Defaults to "content".
+func WithContentKey(contentKey string) Option {
+	return func(p *Store) {
+		p.contentKey = contentKey
+	}
+}
+
+func applyClientOptions(opts ...Option) (Store, error) {
+	o := &Store{
+		contentKey: defaultContentKey,
+	}
+
+	for _, opt := range opts {
+		opt(o)
+	}
+
+	if o.collectionName == "" {
+		return Store{}, fmt.Errorf("%w: missing collection name", ErrInvalidOptions)
+	}
+
+	if o.qdrantURL == (url.URL{}) {
+		return Store{}, fmt.Errorf("%w: missing Qdrant URL", ErrInvalidOptions)
+	}
+
+	if o.embedder == nil {
+		return Store{}, fmt.Errorf("%w: missing embedder", ErrInvalidOptions)
+	}
+
+	return *o, nil
+}

vectorstores/qdrant/qdrant.go

@@ -0,0 +1,108 @@
+package qdrant
+
+import (
+	"context"
+	"errors"
+	"net/url"
+
+	"github.com/tmc/langchaingo/embeddings"
+	"github.com/tmc/langchaingo/schema"
+	"github.com/tmc/langchaingo/vectorstores"
+)
+
+type Store struct {
+	embedder       embeddings.Embedder
+	collectionName string
+	qdrantURL      url.URL
+	apiKey         string
+	contentKey     string
+}
+
+var _ vectorstores.VectorStore = Store{}
+
+func New(opts ...Option) (Store, error) {
+	s, err := applyClientOptions(opts...)
+	if err != nil {
+		return Store{}, err
+	}
+	return s, nil
+}
+
+func (s Store) AddDocuments(ctx context.Context,
+	docs []schema.Document,
+	_ ...vectorstores.Option,
+) ([]string, error) {
+	texts := make([]string, 0, len(docs))
+	for _, doc := range docs {
+		texts = append(texts, doc.PageContent)
+	}
+
+	vectors,
+		err := s.embedder.EmbedDocuments(ctx, texts)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(vectors) != len(docs) {
+		return nil, errors.New("number of vectors from embedder does not match number of documents")
+	}
+
+	metadatas := make([]map[string]interface{}, 0, len(docs))
+	for i := 0; i < len(docs); i++ {
+		metadata := make(map[string]interface{}, len(docs[i].Metadata))
+		for key, value := range docs[i].Metadata {
+			metadata[key] = value
+		}
+		metadata[s.contentKey] = texts[i]
+
+		metadatas = append(metadatas, metadata)
+	}
+
+	return s.upsertPoints(ctx, &s.qdrantURL, vectors, metadatas)
+}
+
+func (s Store) SimilaritySearch(ctx context.Context,
+	query string, numDocuments int,
+	options ...vectorstores.Option,
+) ([]schema.Document, error) {
+	opts := s.getOptions(options...)
+
+	filters := s.getFilters(opts)
+
+	scoreThreshold,
+		err := s.getScoreThreshold(opts)
+	if err != nil {
+		return nil, err
+	}
+
+	vector,
+		err := s.embedder.EmbedQuery(ctx, query)
+	if err != nil {
+		return nil, err
+	}
+
+	return s.searchPoints(ctx, &s.qdrantURL, vector, numDocuments, scoreThreshold, filters)
+}
+
+func (s Store) getScoreThreshold(opts vectorstores.Options) (float32, error) {
+	if opts.ScoreThreshold < 0 || opts.ScoreThreshold > 1 {
+		return 0, errors.New("score threshold must be between 0 and 1")
+	}
+	return opts.ScoreThreshold, nil
+}
+
+func (s Store) getFilters(opts vectorstores.Options) any {
+	if opts.Filters != nil {
+		return opts.Filters
+	}
+
+	return nil
+}
+
+func (s Store) getOptions(options ...vectorstores.Option) vectorstores.Options {
+	opts := vectorstores.Options{}
+	for _, opt := range options {
+		opt(&opts)
+	}
+	return opts
+}