│   ├── collection/     # Enhanced collection utilities
│   ├── convert/        # Type conversion utilities
│   ├── exception/      # Runtime exception wrappers
│   ├── io/            # I/O and resource management
│   ├── lang/          # Reflection and language utilities
│   ├── log/           # Logging abstraction
│   ├── text/          # Text processing utilities
│   ├── xml/           # XML processing utilities

The most complex problem is building an authentication/authorization provider like those, but **FastAPI** gives you the tools to do it easily, while doing the heavy lifting for you.

///

## **FastAPI** utilities { #fastapi-utilities }

FastAPI provides several tools for each of these security schemes in the `fastapi.security` module that simplify using these security mechanisms.

# Use Old 403 Authentication Error Status Codes { #use-old-403-authentication-error-status-codes }

Before FastAPI version `0.122.0`, when the integrated security utilities returned an error to the client after a failed authentication, they used the HTTP status code `403 Forbidden`.

# See the License for the specific language governing permissions and
# limitations under the License.
# ==============================================================================
source "${BASH_SOURCE%/*}/utilities/setup.sh"

if [[ `uname -s | grep -P '^MSYS_NT'` ]]; then
  PROFILE_JSON_PATH=$(replace_drive_letter_with_prefix "$TFCI_OUTPUT_WIN_DOCKER_DIR")
  PROFILE_JSON_PATH="$PROFILE_JSON_PATH/profile.json.gz"
else

# ==============================================================================
#
# macOS specific setup for all TF scripts.
#

# Mac version of Core utilities differ in usage. Since our scripts are written
# with the GNU style, we need to set GNU utilities to be default on Mac.
if [[ -n "$(which grealpath)" ]] &&  [[ -n "$(which gstat)" ]]; then
  alias realpath=grealpath
  alias stat=gstat

│   ├── user/                  # User index
│   ├── exbhv/                 # Extended behaviors (repositories)
│   └── exentity/              # Extended entities (domain models)
├── helper/                    # Cross-cutting utilities
├── crawler/                   # Crawling engine
├── sso/                       # SSO implementations
└── ds/                        # Data store connectors

src/main/resources/

# Alte 403-Authentifizierungsfehler-Statuscodes verwenden { #use-old-403-authentication-error-status-codes }

Vor FastAPI-Version `0.122.0` verwendeten die integrierten Sicherheits-Utilities den HTTP-Statuscode `403 Forbidden`, wenn sie dem Client nach einer fehlgeschlagenen Authentifizierung einen Fehler zurückgaben.

### I/O Layer

- **`org.codelibs.curl.io.ContentCache`**: Handles automatic in-memory or on-disk caching of request/response bodies
- **`org.codelibs.curl.io.ContentOutputStream`**: Streaming utilities for efficient content handling

### Key Design Patterns

1. **Fluent Builder Pattern**: `CurlRequest` uses method chaining for configuration

///

/// info

In this example we use invented custom headers `X-Key` and `X-Token`.

But in real cases, when implementing security, you would get more benefits from using the integrated [Security utilities (the next chapter)](../security/index.md){.internal-link target=_blank}.

///

## Dependencies errors and return values { #dependencies-errors-and-return-values }

netsh interface portproxy add v4tov4 listenaddress=$IP_ADDR listenport=80 connectaddress=169.254.169.254 connectport=80
# A local firewall rule for the container is added in