# Streaming

## Stream JSON Lines

To stream JSON Lines, declare the return type and use `yield` to return the data.

```python
@app.get("/items/stream")
async def stream_items() -> AsyncIterable[Item]:
    for item in items:
        yield item
```

## Server-Sent Events (SSE)

To stream Server-Sent Events, use `response_class=EventSourceResponse` and `yield` items from the endpoint.

     */
    LlmChatResponse chat(LlmChatRequest request);

    /**
     * Performs a streaming chat completion request.
     * The callback is invoked for each chunk of the response.
     *
     * @param request the chat request containing messages and parameters
     * @param callback the callback to receive streaming chunks
     * @throws LlmException if an error occurs during the request
     */

            throw new LlmException("LLM chat request failed", e);
        }
    }

    /**
     * Performs a streaming chat completion request using the configured LLM client.
     *
     * @param request the chat request
     * @param callback the callback to receive streaming chunks
     * @throws LlmException if LLM is not available or an error occurs
     */

 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.llm;

/**
 * Callback interface for receiving streaming chat responses from LLM.
 */
@FunctionalInterface
public interface LlmStreamCallback {

    /**
     * Called for each chunk of the streaming response.
     *
     * @param chunk the text chunk from the LLM response
     * @param done true if this is the final chunk
     */

        return this;
    }

    /**
     * Checks if streaming is enabled.
     *
     * @return true if streaming is enabled
     */
    public boolean isStream() {
        return stream;
    }

    /**
     * Sets whether streaming is enabled.
     *
     * @param stream true to enable streaming
     * @return this request for method chaining
     */

"""
Test that async streaming endpoints can be cancelled without hanging.

Ref: https://github.com/fastapi/fastapi/issues/14680
"""

from collections.abc import AsyncIterable

import anyio
import pytest
from fastapi import FastAPI
from fastapi.responses import StreamingResponse

pytestmark = [
    pytest.mark.anyio,
    pytest.mark.filterwarnings("ignore::pytest.PytestUnraisableExceptionWarning"),
]


app = FastAPI()

For more details about the extension, refer to the README on the [GitHub repository](https://github.com/fastapi/fastapi-vscode).

## Setup and Installation { #setup-and-installation }

 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.chat;

/**
 * Callback interface for receiving notifications about chat processing phases.
 * Used for SSE streaming to notify clients about the current processing state.
 */
public interface ChatPhaseCallback {

    /** Phase name for intent detection */
    String PHASE_INTENT = "intent";

     * For files larger than {@value #MAX_BUF_SIZE} bytes (10MB), an
     * {@link IORuntimeException} will be thrown to prevent OutOfMemoryError.
     * For large files, use streaming APIs instead.
     * </p>
     *
     * @param file
     *            The file. Must not be {@literal null}.
     * @return A byte array containing the contents of the file.

SSE is a standard for streaming data from the server to the client over HTTP.

Each event is a small text block with "fields" like `data`, `event`, `id`, and `retry`, separated by blank lines.

It looks like this:

```
data: {"name": "Portal Gun", "price": 999.99}

data: {"name": "Plumbus", "price": 32.99}

```