It uses Marshmallow underneath to do the data validation. And it was created by the same developers.

It's a great tool and I have used it a lot too, before having **FastAPI**.

/// info

Webargs was created by the same Marshmallow developers.

///

/// check | Inspired **FastAPI** to

Have automatic validation of incoming request data.

///

        .inOrder();
  }

  public void testCopyOf_array_empty() {
    /*
     * We don't guarantee the same-as property, so we aren't obligated to test it. However, it's
     * useful in testing - when two things are the same then one can't have bugs the other doesn't.
     */
    assertThat(ImmutableDoubleArray.copyOf(new double[0]))
        .isSameInstanceAs(ImmutableDoubleArray.of());
  }

  }

  /**
   * Constructs a {@code LinkedHashMultimap} with the same mappings as the specified multimap. If a
   * key-value mapping appears multiple times in the input multimap, it only appears once in the
   * constructed multimap. The new multimap has the same {@link Multimap#entries()} iteration order
   * as the input multimap, except for excluding duplicate mappings.
   *

 * exposes at least one public static final constant of the same type, one of the constants will be
 * used; or if the class exposes a public parameter-less constructor then it will be "new"d and
 * returned.
 *
 * <p>All default instances returned by {@link #get} are generics-safe. Clients won't get type
 * errors for using {@code get(Comparator.class)} as a {@code Comparator<Foo>}, for example.

    // Avoid ambiguous parameters. Safe characters are never modified so if
    // space is a safe character then setting plusForSpace is meaningless.
    if (plusForSpace && safeChars.contains(" ")) {
      throw new IllegalArgumentException(
          "plusForSpace cannot be specified when space is a 'safe' character");
    }
    this.plusForSpace = plusForSpace;
    this.safeOctets = createSafeOctets(safeChars);
  }

{% endif %}

{% endfor %}

</div>

## Top Contributors

Here are the **Top Contributors**. 👷

These users have [created the most Pull Requests](help-fastapi.md#create-a-pull-request){.internal-link target=_blank} that have been *merged*.

They have contributed source code, documentation, etc. 📦

<div class="user-list user-list-center">

{% for user in (contributors.values() | list)[:50] %}

                "tearDownTwo should have been run before tearDownOne", false, tearDownOne.ran);
          }
        };

    SimpleTearDown tearDownTwo = new SimpleTearDown(callback);
    stack.addTearDown(tearDownTwo);

    assertEquals(false, tearDownOne.ran);
    assertEquals(false, tearDownTwo.ran);

    stack.runTearDown();

    assertEquals("tearDownOne should have run", true, tearDownOne.ran);

To create the callback *path operation* use the same `APIRouter` you created above.

It should look just like a normal FastAPI *path operation*:

* It should probably have a declaration of the body it should receive, e.g. `body: InvoiceEvent`.
* And it could also have a declaration of the response it should return, e.g. `response_model=InvoiceEventReceived`.

        assertTrue(region.hasAccess(RdmaAccess.LOCAL_READ), "Should have local read access");
        assertTrue(region.hasAccess(RdmaAccess.LOCAL_WRITE), "Should have local write access");
        assertFalse(region.hasAccess(RdmaAccess.REMOTE_READ), "Should not have remote read access");

        // Test cleanup
        region.close();

  }

  public void testBadArguments_plusforspace() {
    // space can be a safe char if plusForSpace is false
    PercentEscaper unused = new PercentEscaper(" ", false);

    // space cannot be a safe char is plusForSpace is true
    String msg = "plusForSpace cannot be specified when space is a 'safe' character";
    IllegalArgumentException expected =