ChromaDB Vector Store Provider

The ChromaDB provider implements the vectorstore.VectorStore interface using ChromaDB’s REST API. ChromaDB is an open-source embedding database with a simple API, supporting multi-tenant deployments.

Choose ChromaDB for its simplicity and ease of setup. ChromaDB is straightforward to run locally with Docker and requires minimal configuration, making it a good choice for prototyping and small-to-medium workloads. Its multi-tenant support (tenants and databases) allows data isolation without separate deployments.

Installation

go get github.com/lookatitude/beluga-ai/rag/vectorstore/providers/chroma

Start ChromaDB locally:

docker run -p 8000:8000 chromadb/chroma

Quick Start

package main

import (
    "context"
    "log"

    "github.com/lookatitude/beluga-ai/config"
    "github.com/lookatitude/beluga-ai/rag/vectorstore"
    "github.com/lookatitude/beluga-ai/schema"
    _ "github.com/lookatitude/beluga-ai/rag/vectorstore/providers/chroma"
)

func main() {
    store, err := vectorstore.New("chroma", config.ProviderConfig{
        BaseURL: "http://localhost:8000",
        Options: map[string]any{
            "collection": "my_documents",
        },
    })
    if err != nil {
        log.Fatal(err)
    }

    ctx := context.Background()

    docs := []schema.Document{
        {ID: "doc1", Content: "Go is a statically typed language", Metadata: map[string]any{"lang": "en"}},
    }
    embeddings := [][]float32{make([]float32, 1536)}

    err = store.Add(ctx, docs, embeddings)
    if err != nil {
        log.Fatal(err)
    }
}

Configuration

Parameter	Type	Default	Description
BaseURL	string	(required)	ChromaDB server URL
Options["collection"]	string	(none)	Collection name
Options["tenant"]	string	default_tenant	Tenant name
Options["database"]	string	default_database	Database name

Collection Management

The provider automatically creates collections via get_or_create semantics. You can also explicitly ensure a collection exists:

import (
    chromastore "github.com/lookatitude/beluga-ai/rag/vectorstore/providers/chroma"
)

store := chromastore.New("http://localhost:8000",
    chromastore.WithCollection("my_collection"),
)

err := store.EnsureCollection(ctx)
if err != nil {
    log.Fatal(err)
}

Direct Construction

store := chromastore.New("http://localhost:8000",
    chromastore.WithCollection("my_collection"),
    chromastore.WithTenant("my_tenant"),
    chromastore.WithDatabase("my_database"),
)

Pre-Resolved Collection ID

If you already know the collection ID, skip the resolution step:

store := chromastore.New("http://localhost:8000",
    chromastore.WithCollectionID("abc-123-def-456"),
)

Metadata Filtering

ChromaDB supports metadata filtering with its $eq operator:

results, err := store.Search(ctx, queryVec, 10,
    vectorstore.WithFilter(map[string]any{
        "lang": "en",
    }),
)

Search with Threshold

ChromaDB returns distances (lower = more similar). The provider converts them to similarity scores using the formula 1 / (1 + distance):

results, err := store.Search(ctx, queryVec, 10,
    vectorstore.WithThreshold(0.5),
)

Multi-Tenancy

ChromaDB supports multi-tenant deployments via the tenant and database parameters:

store, err := vectorstore.New("chroma", config.ProviderConfig{
    BaseURL: "http://localhost:8000",
    Options: map[string]any{
        "collection": "shared_docs",
        "tenant":     "org_123",
        "database":   "prod",
    },
})