# Path Parameters and Numeric Validations

In the same way that you can declare more validations and metadata for query parameters with `Query`, you can declare the same type of validations and metadata for path parameters with `Path`.

## Import Path

First, import `Path` from `fastapi`, and import `Annotated`:

//// tab | Python 3.10+

```Python hl_lines="1  3"
{!> ../../docs_src/path_params_numeric_validations/tutorial001_an_py310.py!}
```

In your production system, you probably have a frontend created with a modern framework like React, Vue.js or Angular.

And to communicate using WebSockets with your backend you would probably use your frontend's utilities.

Or you might have a native mobile application that communicates with your WebSocket backend directly, in native code.

Or you might have any other way to communicate with the WebSocket endpoint.

---

func isDirectiveReplace(value string) bool {
	return value == replaceDirective
}

// userMetadataKeyPrefixes contains the prefixes of used-defined metadata keys.
// All values stored with a key starting with one of the following prefixes
// must be extracted from the header.
var userMetadataKeyPrefixes = []string{
	"x-amz-meta-",
	"x-minio-meta-",
}

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The result of calling it is something that can be encoded with the Python standard <a href="https://docs.python.org/3/library/json.html#json.dumps" class="external-link" target="_blank">`json.dumps()`</a>.

It doesn't return a large `str` containing the data in JSON format (as a string). It returns a Python standard data structure (e.g. a `dict`) with values and sub-values that are all compatible with JSON.

/// note

  /**
   * In a response, this field's name "no-cache" is misleading. It doesn't prevent us from caching
   * the response; it only means we have to validate the response with the origin server before
   * returning it. We can do this with a conditional GET.
   *
   * In a request, it means do not use a cache to satisfy the request.
   */
  @get:JvmName("noCache") val noCache: Boolean,

 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *

 * are typically shares amongst all tests, a fresh instance will be
 * received here. Use with @BeforeAll and @AfterAll, is not supported.
 *
 * There are 3 ids for instances
 * - The test instance default (passed into constructor)
 * - The test lifecycle default (passed into test method, plus @BeforeEach, @AfterEach)
 * - named instances with @MockWebServerInstance.
 */
@ExperimentalOkHttpApi
class MockWebServerExtension :

/*
 * Copyright (C) 2008 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

/*
 * Copyright (C) 2011 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License