## Installation

<div class="termy">

```console
$ pip install fastapi

---> 100%
```

</div>

# Custom Request and APIRoute class { #custom-request-and-apiroute-class }

In some cases, you may want to override the logic used by the `Request` and `APIRoute` classes.

In particular, this may be a good alternative to logic in a middleware.

For example, if you want to read or manipulate the request body before it is processed by your application.

/// danger

This is an "advanced" feature.

     *
     * @return the location of the problem, never {@code null}
     */
    @Nonnull
    String getLocation();

    /**
     * Gets the exception that caused this problem (if any).
     *
     * @return the exception that caused this problem or {@code null} if not applicable
     */
    @Nullable
    Exception getException();

    /**
     * Gets the message that describes this problem.
     *

    caused by looking up CA certificates. This is now fixed.


## Version 3.1.0

_2016-02-06_

 *  New: WebSockets now defer some writes. This should improve performance for
    some applications.
 *  New: Override `equals()` and `hashCode()` in our new cookie class. This
    class now defines equality by value rather than by reference.

   * on arbitrary {@link Map} classes.
   *
   * <p>The {@code factory}-generated and {@code backingMap} classes determine the table iteration
   * order. However, the table's {@code row()} method returns instances of a different class than
   * {@code factory.get()} does.
   *
   * <p>Call this method only when the simpler factory methods in classes like {@link

import java.lang.annotation.RetentionPolicy;
import java.util.Collection;
import java.util.LinkedHashSet;
import java.util.Set;
import java.util.SortedSet;

/**
 * Optional features of classes derived from {@code Collection}.
 *
 * @author George van den Driessche
 */
@SuppressWarnings("rawtypes") // maybe avoidable if we rework the whole package?
@GwtCompatible

 * Abstraction of an artifact repository. Artifact repositories can be remote, local, or even build reactor or
 * IDE workspace.
 *
 * @deprecated Avoid use of this type, if you need access to local repository use repository system classes instead.
 */
@Deprecated
public interface ArtifactRepository {
    String pathOf(Artifact artifact);

    String pathOfRemoteRepositoryMetadata(ArtifactMetadata artifactMetadata);

  // public named classes with a public default constructor.

  public static final class DoublesAsListGenerator extends TestDoubleListGenerator {
    @Override
    protected List<Double> create(Double[] elements) {
      return asList(elements);
    }
  }

  public static final class DoublesAsListHeadSubListGenerator extends TestDoubleListGenerator {
    @Override

  public static final class TwoArgConstructorException extends Exception {
    public TwoArgConstructorException(String message, Throwable cause) {
      super(message, cause);
    }
  }

  public static final class TwoArgConstructorRuntimeException extends RuntimeException {
    public TwoArgConstructorRuntimeException(String message, Throwable cause) {
      super(message, cause);
    }
  }

                    return (int) misses.incrementAndGet();
                  }
                });

    // To start, fill up the cache.
    // Each miss both increments the counter and causes the map to grow by one,
    // so until evictions begin, the size of the map is the greatest return
    // value seen so far
    while (cache.getUnchecked(nextRandomKey()) < maximumSize) {}

    requests.set(0);