There was also an "OpenID" specification. That tried to solve the same thing as **OpenID Connect**, but was not based on OAuth2.

So, it was a complete additional system.

It is not very popular or used nowadays.

## OpenAPI { #openapi }

OpenAPI (previously known as Swagger) is the open specification for building APIs (now part of the Linux Foundation).

* <a href="https://github.com/OAI/OpenAPI-Specification/blob/main/versions/3.1.0.md#parameter-object" class="external-link" target="_blank">`Parameter Object` (in the specification)</a> that was used by FastAPI's:
    * `Path()`
    * `Query()`
    * `Header()`
    * `Cookie()`

As you see, the method names now have the tag and then the function name, now they don't include information from the URL path and the HTTP operation.

### Preprocess the OpenAPI Specification for the Client Generator { #preprocess-the-openapi-specification-for-the-client-generator }

The generated code still has some **duplicated information**.

)

// HTTPRangeSpec represents a range specification as supported by S3 GET
// object request.
//
// Case 1: Not present -> represented by a nil RangeSpec
// Case 2: bytes=1-10 (absolute start and end offsets) -> RangeSpec{false, 1, 10}
// Case 3: bytes=10- (absolute start offset with end offset unspecified) -> RangeSpec{false, 10, -1}
// Case 4: bytes=-30 (suffix length specification) -> RangeSpec{true, -30, -1}
type HTTPRangeSpec struct {

{* ../../docs_src/request_forms/tutorial001_an_py39.py hl[9] *}

For example, in one of the ways the OAuth2 specification can be used (called "password flow") it is required to send a `username` and `password` as form fields.

The <abbr title="specification">spec</abbr> requires the fields to be exactly named `username` and `password`, and to be sent as form fields, not JSON.

For optimal production setup MinIO recommends Linux kernel version 4.x and later.

## Erasure Code (Multiple Drives / Servers)

| Item                                                            | Specification |
|:----------------------------------------------------------------|:--------------|
| Maximum number of servers per cluster                           | no-limit      |

/// note | Technical details

In the OpenAPI specification it is called the <a href="https://github.com/OAI/OpenAPI-Specification/blob/main/versions/3.0.3.md#operation-object" class="external-link" target="_blank">Operation Object</a>.

///

To see what exactly you can include in the responses, you can check these sections in the OpenAPI specification:

* <a href="https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.1.0.md#responses-object" class="external-link" target="_blank">OpenAPI Responses Object</a>, it includes the `Response Object`.

                extractFile(ent.getKey(), embeddedFile, writer);
            }
        }
    }

    /**
     * Gets the embedded file from a file specification, trying different platform-specific variants.
     * @param fileSpec the file specification
     * @return the embedded file, or null if not found
     */
    protected PDEmbeddedFile getEmbeddedFile(final PDComplexFileSpecification fileSpec) {

            }
        }
        return SSLConnectionSocketFactory.getSocketFactory();
    }

    /**
     * Builds the cookie specification registry.
     *
     * @return The configured cookie specification registry
     */
    protected Lookup<CookieSpecProvider> buildCookieSpecRegistry() {
        if (cookieSpecRegistry != null) {
            return cookieSpecRegistry;
        }