Key concepts in Direct Line API 3.0
APPLIES TO: SDK v3
You can enable communication between your bot and your own client application by using the Direct Line API. This article introduces key concepts in Direct Line API 3.0 and provides information about relevant developer resources. You can build a client using the SDK, REST API, or Web Chat.
Authentication
Direct Line API 3.0 requests can be authenticated either by using a secret that you obtain from the Direct Line channel configuration page in the Azure Portal or by using a token that you obtain at runtime. For more information, see Authentication.
Starting a conversation
Direct Line conversations are explicitly opened by clients and may run as long as the bot and client participate and have valid credentials. For more information, see Start a conversation.
Sending messages
Using Direct Line API 3.0, a client can send messages to your bot by issuing HTTP POST requests. A client may send a single message per request. For more information, see Send an activity to the bot.
Receiving messages
Using Direct Line API 3.0, a client can receive messages from your bot either via WebSocket stream or by issuing HTTP GET requests. Using either of these techniques, a client may receive multiple messages from the bot at a time as part of an ActivitySet. For more information, see Receive activities from the bot.
Developer resources
Client libraries
The Bot Framework provides client libraries that facilitate access to Direct Line API 3.0 via C# and Node.js.
To use the .NET client library within a Visual Studio project, install the
Microsoft.Bot.Connector.DirectLineNuGet package.To use the Node.js client library, install the
botframework-directlinejslibrary using NPM (or download the source).
Sample code
The BotBuilder-Samples GitHub repo contains multiple samples that show how to use Direct Line API 3.0 with C# and Node.js.
| Sample | Language | Description |
|---|---|---|
| Direct Line Bot Sample | C# | A sample bot and a custom client communicating to each other using the Direct Line API. |
| Direct Line Bot Sample (using client WebSockets) | C# | A sample bot and a custom client communicating to each other using the Direct Line API and WebSockets. |
| Direct Line Bot Sample | JavaScript | A sample bot and a custom client communicating to each other using the Direct Line API. |
| Direct Line Bot Sample (using client WebSockets) | JavaScript | A sample bot and a custom client communicating to each other using the Direct Line API and WebSockets. |
Web chat control
The Bot Framework provides a control that enables you to embed a Direct-Line-powered bot into your client application. For more information, see the Microsoft Bot Framework WebChat control.