Every time you "log in with" Facebook, Google, GitHub, Microsoft, X (Twitter), that application is using OAuth2 with scopes.

In this section you will see how to manage authentication and authorization with the same OAuth2 with scopes in your **FastAPI** application.

/// warning

This is a more or less advanced section. If you are just starting, you can skip it.

 * by a G, selecting appropriate tests by matching them against specified features.
 *
 * @param <B> The concrete type of this builder (the 'self-type'). All the Builder methods of this
 *     class (such as {@link #named}) return this type, so that Builder methods of more derived
 *     classes can be chained onto them without casting.

    @Test
    void testGetDefaultPort() {
        // This test verifies that the handler returns the correct default HTTP port.
        assertEquals(Handler.DEFAULT_HTTP_PORT, handler.getDefaultPort(), "Default port should be 80 for HTTP.");
    }

    @Test
    void testOpenConnection_HttpProtocol_ReturnsNtlmHttpURLConnection() throws Exception {

            this.limitPercentage = Integer.parseInt(limitPercentage.substring(0, limitPercentage.length() - 1));
        } else {
            this.limitPercentage = Integer.parseInt(limitPercentage);
        }

        if (this.limitPercentage > 100) {
            this.limitPercentage = 100;
        } else if (this.limitPercentage < 1) {
            this.limitPercentage = 1;
        }
    }

    /**
     * Returns the flags currently in use for this message.
     *
     * @return An <code>int</code> containing the flags in use for this
     *         message.
     */
    public int getFlags() {
        return this.flags;
    }

    /**
     * Sets the flags for this message.
     *
     * @param flags
     *            The flags for this message.
     */
    public void setFlags(final int flags) {

 * Licensed to the Apache Software Foundation (ASF) under one
 * or more 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

  public final int port;

  public SlackApi(String clientId, String clientSecret, int port) {
    this.httpClient = new OkHttpClient.Builder()
        .build();
    this.moshi = new Moshi.Builder()
        .add(new SlackJsonAdapters())
        .build();
    this.clientId = clientId;
    this.clientSecret = clientSecret;
    this.port = port;
  }

  /** See https://api.slack.com/docs/oauth. */

/*
 * © 2017 AgNO3 Gmbh & Co. KG
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of

        validate(form, messages -> {}, this::asListHtml);
        final String id = form.id;
        requestHeaderService.getRequestHeader(id).ifPresent(entity -> {
            copyBeanToBean(entity, form, op -> {});
        }).orElse(() -> {
            throwValidationError(messages -> messages.addErrorsCrudCouldNotFindCrudTable(GLOBAL, id), this::asListHtml);
        });
        saveToken();

      and distribution as defined by Sections 1 through 9 of this document.

      "Licensor" shall mean the copyright owner or entity authorized by
      the copyright owner that is granting the License.

      "Legal Entity" shall mean the union of the acting entity and all
      other entities that control, are controlled by, or are under common
      control with that entity. For the purposes of this definition,