> ## Documentation Index
> Fetch the complete documentation index at: https://docs.dify.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# App

> This document details how plugins can reverse invoke App services within the Dify platform. It covers three types of interfaces Chat interface (for Chatbot/Agent/Chatflow applications), Workflow interface, and Completion interface, providing entry points, invocation specifications, and practical code examples for each.

Reverse invoking an App means that a plugin can access data from an App within Dify. This module supports both streaming and non-streaming App calls. If you are unfamiliar with the basic concepts of reverse invocation, please first read [Reverse Invocation of Dify Services](/en/develop-plugin/features-and-specs/advanced-development/reverse-invocation).

**Interface Types**:

* For `Chatbot/Agent/Chatflow` type applications, they are all chat-based applications and thus share the same input and output parameter types. Therefore, they can be uniformly treated as the **Chat Interface.**
* For Workflow applications, they occupy a separate **Workflow Interface.**
* For Completion (text generation application) applications, they occupy a separate **Completion Interface**.

Please note that plugins are only allowed to access Apps within the Workspace where the plugin resides.

### Call the Chat Interface

#### **Entry Point**

```python theme={null}
    self.session.app.chat
```

#### **Interface Specification**

```python theme={null}
    def invoke(
        self,
        app_id: str,
        inputs: dict,
        response_mode: Literal["streaming", "blocking"],
        conversation_id: str,
        files: list,
    ) -> Generator[dict, None, None] | dict:
        pass
```

When `response_mode` is `streaming`, this interface will directly return `Generator[dict]`. Otherwise, it returns `dict`. For specific interface fields, please refer to the return results of `ServiceApi`.

#### **Use Case**

We can call a Chat type App within an `Endpoint` and return the result directly.

```python theme={null}
import json
from typing import Mapping
from werkzeug import Request, Response
from dify_plugin import Endpoint

class Duck(Endpoint):
    def _invoke(self, r: Request, values: Mapping, settings: Mapping) -> Response:
        """
        Invokes the endpoint with the given request.
        """
        app_id = values["app_id"]

        def generator():
            # Note: The original example incorrectly called self.session.app.workflow.invoke
            # It should call self.session.app.chat.invoke for a chat app.
            # Assuming a chat app is intended here based on the section title.
            response = self.session.app.chat.invoke(
                app_id=app_id, 
                inputs={}, # Provide actual inputs as needed
                response_mode="streaming", 
                conversation_id="some-conversation-id", # Provide a conversation ID if needed
                files=[]
            )

            for data in response:
                yield f"{json.dumps(data)} <br>"

        return Response(generator(), status=200, content_type="text/html")
```

### Call the Workflow Interface

#### **Entry Point**

```python theme={null}
    self.session.app.workflow
```

#### **Interface Specification**

```python theme={null}
    def invoke(
        self,
        app_id: str,
        inputs: dict,
        response_mode: Literal["streaming", "blocking"],
        files: list,
    ) -> Generator[dict, None, None] | dict:
        pass
```

### Call the Completion Interface

#### **Entry Point**

```python theme={null}
    self.session.app.completion
```

**Interface Specification**

```python theme={null}
    def invoke(
        self,
        app_id: str,
        inputs: dict,
        response_mode: Literal["streaming", "blocking"],
        files: list,
    ) -> Generator[dict, None, None] | dict:
        pass
```

## Related Resources

* [Reverse Invocation of Dify Services](/en/develop-plugin/features-and-specs/advanced-development/reverse-invocation) - Understand the fundamental concepts of reverse invocation
* [Reverse Invocation Model](/en/develop-plugin/features-and-specs/advanced-development/reverse-invocation-model) - Learn how to call model capabilities within the platform
* [Reverse Invocation Tool](/en/develop-plugin/features-and-specs/advanced-development/reverse-invocation-tool) - Learn how to call other plugins
* [Develop a Slack Bot Plugin](/en/develop-plugin/dev-guides-and-walkthroughs/develop-a-slack-bot-plugin) - A practical application case using reverse invocation
* [Develop Extension Plugins](/en/develop-plugin/dev-guides-and-walkthroughs/endpoint) - Learn how to develop extension plugins

***

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