///

## Advanced User Guide { #advanced-user-guide }

There is also an **Advanced User Guide** that you can read later after this **Tutorial - User guide**.

The **Advanced User Guide** builds on this one, uses the same concepts, and teaches you some extra features.

But you should first read the **Tutorial - User Guide** (what you are reading right now).

        bufferIndex += 2;

        // Read flags
        this.flags = SMBUtil.readInt4(buffer, bufferIndex);
        bufferIndex += 4;

        // Validate remaining buffer size for algorithms
        if (len < 8 + (compressionCount * 2)) {
            throw new SMBProtocolDecodingException("Buffer too small for compression algorithms");
        }

        // Read compression algorithms

// Read is never called with an empty buffer.
type testNonEmptyReader struct{ io.Reader }

func (r testNonEmptyReader) Read(b []byte) (int, error) {
	if len(b) == 0 {
		return 0, errors.New("unexpected empty Read call")
	}
	return r.Reader.Read(b)
}

func TestFileReader(t *testing.T) {
	type (
		testRead struct { // Read(cnt) == (wantStr, wantErr)
			cnt     int

    clientListener.assertFailure(
      SocketTimeoutException::class.java,
      "timeout",
      "Read timed out",
    )
    assertThat(webSocket.close(1000, null)).isFalse()
  }

  /**
   * There's no read timeout when reading the first byte of a new frame. But as soon as we start
   * reading a frame we enable the read timeout. In this test we have the server returning the first
   * byte of a frame but no more frames.
   */

# Test Client - `TestClient`

You can use the `TestClient` class to test FastAPI applications without creating an actual HTTP and socket connection, just communicating directly with the FastAPI code.

Read more about it in the [FastAPI docs for Testing](https://fastapi.tiangolo.com/tutorial/testing/).

You can import it directly from `fastapi.testclient`:

```python
from fastapi.testclient import TestClient
```

            assertArrayEquals(originalBuffer, buffer);
        }
    }

    @Nested
    @DisplayName("Read Bytes Wire Format Tests")
    class ReadBytesWireFormatTests {

        @Test
        @DisplayName("Should read valid structure size of 4")
        void testReadBytesWireFormatValid() throws SMBProtocolDecodingException {
            byte[] buffer = new byte[1024];

type diskHealthWrapper struct {
	tracker *healthDiskCtxValue
	r       io.Reader
	w       io.Writer
}

func (d *diskHealthWrapper) Read(p []byte) (int, error) {
	if d.r == nil {
		return 0, fmt.Errorf("diskHealthWrapper: Read with no reader")
	}
	n, err := d.r.Read(p)
	if err == nil || err == io.EOF && n > 0 {
		d.tracker.logSuccess()
	}
	return n, err
}

It would also mean that if you get data from the `Request` object directly (for example, read the body) it won't be validated, converted or documented (with OpenAPI, for the automatic API user interface) by FastAPI.

// ReadMultipleReq contains information of multiple files to read from disk.
type ReadMultipleReq struct {
	Bucket       string   `msg:"bk"`           // Bucket. Can be empty if multiple buckets.
	Prefix       string   `msg:"pr,omitempty"` // Shared prefix of all files. Can be empty. Will be joined to filename without modification.
	Files        []string `msg:"fl"`           // Individual files to read.

import org.jspecify.annotations.NullMarked;

/**
 * A Ticker whose value can be advanced programmatically in test.
 *
 * <p>The ticker can be configured so that the time is incremented whenever {@link #read} is called:
 * see {@link #setAutoIncrementStep}.
 *
 * <p>This class is thread-safe.
 *
 * @author Jige Yu
 * @since 10.0
 */
@NullMarked
@GwtCompatible
public class FakeTicker extends Ticker {