Connect to Qdrant

This page describes how consuming apps connect to a Qdrant resource that’s already modeled in your AppHost. For the AppHost API surface — adding a Qdrant resource, API key parameters, data volumes, and more — see Qdrant Hosting integration.

When you reference a Qdrant resource from your AppHost, Aspire injects the connection information into the consuming app as environment variables. Your app can either read those environment variables directly — the pattern works the same from any language — or, in C#, use the Aspire Qdrant client integration for automatic dependency injection, health checks, and telemetry.

Connection properties

Aspire exposes each property as an environment variable named [RESOURCE]_[PROPERTY]. For instance, the HttpUri property of a resource called qdrant becomes QDRANT_HTTPURI.

Qdrant exposes both a REST API and a gRPC API. The Qdrant resource exposes the following connection properties:

Property Name	Description
GrpcHost	The hostname of the Qdrant gRPC endpoint
GrpcPort	The port number the Qdrant gRPC endpoint is listening on (default: 6334)
HttpHost	The hostname of the Qdrant REST endpoint
HttpPort	The port number the Qdrant REST endpoint is listening on (default: 6333)
ApiKey	The API key for authentication
Uri	The gRPC connection URI, with the format http://{GrpcHost}:{GrpcPort}
HttpUri	The REST connection URI, with the format http://{HttpHost}:{HttpPort}

Example connection strings:

Uri: http://localhost:6334
HttpUri: http://localhost:6333

Connect from your app

Pick the language your consuming app is written in. Each example assumes your AppHost adds a Qdrant resource named qdrant and references it from the consuming app.

C#

For C# apps, the recommended approach is the Aspire Qdrant client integration. It registers a QdrantClient through dependency injection and adds health checks and telemetry automatically. If you’d rather read environment variables directly, see the Read environment variables section at the end of this tab.

Install the client integration

Install the 📦 Aspire.Qdrant.Client NuGet package in the client-consuming project:

.NET CLI

.NET CLI — Add Aspire.Qdrant.Client package

dotnet add package Aspire.Qdrant.Client

Program.cs (C# file-based app)

Program.cs

#:package Aspire.Qdrant.Client@*

PackageReference (*.csproj)

XML — Add Aspire.Qdrant.Client package reference

<PackageReference Include="Aspire.Qdrant.Client" Version="*" />

Add the Qdrant client

In Program.cs, call AddQdrantClient on your IHostApplicationBuilder to register a QdrantClient:

C# — Program.cs

builder.AddQdrantClient(connectionName: "qdrant");

Consiglio

The connectionName must match the Qdrant resource name from the AppHost. For more information, see Add Qdrant resource.

Resolve the client through dependency injection:

C# — ExampleService.cs

public class ExampleService(QdrantClient client)
{
    // Use client...
}

Add keyed Qdrant clients

To register multiple QdrantClient instances with different connection names, use AddKeyedQdrantClient:

C# — Program.cs

builder.AddKeyedQdrantClient(name: "mainQdrant");
builder.AddKeyedQdrantClient(name: "loggingQdrant");

Then resolve each instance by key:

C# — ExampleService.cs

public class ExampleService(
    [FromKeyedServices("mainQdrant")] QdrantClient mainClient,
    [FromKeyedServices("loggingQdrant")] QdrantClient loggingClient)
{
    // Use clients...
}

For more information on keyed services, see .NET dependency injection: Keyed services.

Configuration

The Aspire Qdrant client integration offers multiple ways to provide configuration.

Connection strings. When using a connection string from the ConnectionStrings configuration section, pass the connection name to AddQdrantClient:

C# — Program.cs

builder.AddQdrantClient("qdrant");

The connection string is resolved from the ConnectionStrings section. By default, the QdrantClient uses the gRPC endpoint:

JSON — appsettings.json

{
  "ConnectionStrings": {
    "qdrant": "Endpoint=http://localhost:6334;Key=your-api-key"
  }
}

Configuration providers. The client integration supports Microsoft.Extensions.Configuration. It loads QdrantSettings from appsettings.json (or any other configuration source) by using the Aspire:Qdrant:Client key:

JSON — appsettings.json

{
  "Aspire": {
    "Qdrant": {
      "Client": {
        "Endpoint": "http://localhost:6334/",
        "Key": "your-api-key",
        "DisableHealthChecks": false,
        "DisableTracing": false
      }
    }
  }
}

Inline delegates. Pass an Action<QdrantSettings> to configure settings inline, for example to set the API key:

C# — Program.cs

builder.AddQdrantClient(
    "qdrant",
    settings => settings.Key = "your-api-key");

Client integration health checks

Aspire client integrations enable health checks by default. The Qdrant client integration adds a health check that verifies the Qdrant server is reachable. The health check is wired into the /health HTTP endpoint, where all registered health checks must pass before the app is considered ready to accept traffic.

Observability and telemetry

The Aspire Qdrant client integration automatically configures logging through OpenTelemetry.

Logging categories:

• Qdrant.Client

The Qdrant integration doesn’t currently emit tracing activities or metrics because they aren’t supported by the Qdrant.Client library.

Read environment variables in C#

If you prefer not to use the Aspire client integration, you can read the Aspire-injected connection URI and API key from the environment and create a QdrantClient directly using the 📦 Qdrant.Client NuGet package:

C# — Program.cs

using Qdrant.Client;

var endpoint = Environment.GetEnvironmentVariable("QDRANT_URI");
var apiKey = Environment.GetEnvironmentVariable("QDRANT_APIKEY");

var client = new QdrantClient(new Uri(endpoint!), apiKey: apiKey);
// Use client to interact with Qdrant...

Go

Install the official Go client for Qdrant:

Terminal

go get github.com/qdrant/go-client

Read the injected environment variables and connect using gRPC:

Go — main.go

package main

import (
    "context"
    "os"
    "strconv"

    "github.com/qdrant/go-client/qdrant"
)

func main() {
    // Read Aspire-injected connection properties
    grpcHost := os.Getenv("QDRANT_GRPCHOST")
    grpcPort, _ := strconv.Atoi(os.Getenv("QDRANT_GRPCPORT"))
    apiKey := os.Getenv("QDRANT_APIKEY")

    client, err := qdrant.NewClient(&qdrant.Config{
        Host:   grpcHost,
        Port:   grpcPort,
        APIKey: apiKey,
    })
    if err != nil {
        panic(err)
    }
    defer client.Close()

    // Use client to interact with Qdrant...
    _ = context.Background()
}

Python

Install the official Python client for Qdrant:

Terminal

pip install qdrant-client

Read the injected environment variables and connect using gRPC (recommended for performance):

Python — app.py

import os
from qdrant_client import QdrantClient

# Read Aspire-injected connection properties
grpc_host = os.getenv("QDRANT_GRPCHOST")
grpc_port = int(os.getenv("QDRANT_GRPCPORT"))
api_key = os.getenv("QDRANT_APIKEY")

client = QdrantClient(
    host=grpc_host,
    port=grpc_port,
    api_key=api_key,
    prefer_grpc=True,
)

# Use client to interact with Qdrant...

Or connect using the REST endpoint:

Python — Connect via REST

import os
from qdrant_client import QdrantClient

http_uri = os.getenv("QDRANT_HTTPURI")
api_key = os.getenv("QDRANT_APIKEY")

client = QdrantClient(url=http_uri, api_key=api_key)

TypeScript

Install the official TypeScript/JavaScript REST client for Qdrant:

Terminal

npm install @qdrant/js-client-rest

Read the injected environment variables and connect:

TypeScript — index.ts

import { QdrantClient } from '@qdrant/js-client-rest';

// Read Aspire-injected connection properties
const client = new QdrantClient({
    url: process.env.QDRANT_HTTPURI,
    apiKey: process.env.QDRANT_APIKEY,
});

// Use client to interact with Qdrant...

Or connect using individual host and port properties:

TypeScript — Connect with host and port

import { QdrantClient } from '@qdrant/js-client-rest';

const client = new QdrantClient({
    host: process.env.QDRANT_HTTPHOST,
    port: Number(process.env.QDRANT_HTTPPORT),
    apiKey: process.env.QDRANT_APIKEY,
});

Consiglio

If your app expects specific environment variable names different from the Aspire defaults, you can pass individual connection properties from the AppHost. See Qdrant Hosting integration for reference.