# Extending OpenAPI

There are some cases where you might need to modify the generated OpenAPI schema.

In this section you will see how.

## The normal process

The normal (default) process, is as follows.

A `FastAPI` application (instance) has an `.openapi()` method that is expected to return the OpenAPI schema.

# Hermetic Python

Hermetic Python allows not to rely on system-installed Python, and
system-installed Python packages. \
Instead, an independent Python toolchain is registered, ensuring the right
dependencies are always used. \
See https://github.com/bazelbuild/rules_python/ for more details.

### Specifying the Python version

Note: Only a number of minor Python versions are supported at any given time.

   0340; COMBINING GRAVE TONE MARK
   0341; COMBINING ACUTE TONE MARK
   200E; LEFT-TO-RIGHT MARK
   200F; RIGHT-TO-LEFT MARK
   202A; LEFT-TO-RIGHT EMBEDDING
   202B; RIGHT-TO-LEFT EMBEDDING
   202C; POP DIRECTIONAL FORMATTING
   202D; LEFT-TO-RIGHT OVERRIDE
   202E; RIGHT-TO-LEFT OVERRIDE
   206A; INHIBIT SYMMETRIC SWAPPING
   206B; ACTIVATE SYMMETRIC SWAPPING
   206C; INHIBIT ARABIC FORM SHAPING
   206D; ACTIVATE ARABIC FORM SHAPING

*A noticeable trait of this expansion is that it chooses unique hosts such the setup provides maximum protection and availability.*

- Choosing an erasure set for the object is decided during `PutObject()`, object names are used to find the right erasure set using the following pseudo code.

```go
// hashes the key returning an integer.
func sipHashMod(key string, cardinality int, id [16]byte) int {
        if cardinality <= 0 {
                return -1

  // e.g. `meta.k8s.io/v1.DeleteOptions` or `meta.k8s.io/v1.CreateOptions`. This may be
  // different than the options the caller provided. e.g. for a patch request the performed
  // Operation might be a CREATE, in which case the Options will a
  // `meta.k8s.io/v1.CreateOptions` even though the caller provided `meta.k8s.io/v1.PatchOptions`.
  // +optional
  optional k8s.io.apimachinery.pkg.runtime.RawExtension options = 12;

    api(project(":compiler:fir:entrypoint"))
    api(project(":analysis:low-level-api-fir"))
    api(project(":analysis:analysis-api"))
    api(project(":analysis:analysis-api-impl-base"))
    api(project(":analysis:light-classes-base"))
    api(project(":compiler:backend.common.jvm"))
    implementation(project(":compiler:cli-base"))
    implementation(project(":compiler:backend"))
    implementation(project(":compiler:backend.jvm.entrypoint"))

To install:

1) chrome://extensions/
2) click "[+] Developer Mode" in top right
3) "Load unpacked extension..."
4) pick $GOROOT/misc/chrome/gophertool

Physical GPUs or TPUs can also be the target of attacks. [Published
research](https://scholar.google.com/scholar?q=gpu+side+channel) shows that it
might be possible to use side channel attacks on the GPU to leak data from other
running models or processes in the same system. GPUs can also have
implementation bugs that might allow attackers to leave malicious code running
and leak or tamper with applications from other users. Please report

  internal const val B1_FLAG_MASK = 128

  /**
   * Byte 1 mask for the payload length.
   *
   * If this value is [PAYLOAD_SHORT], the next two
   * bytes represent the length. If this value is [PAYLOAD_LONG], the next eight bytes
   * represent the length.
   */
  internal const val B1_MASK_LENGTH = 127

  internal const val OPCODE_CONTINUATION = 0x0
  internal const val OPCODE_TEXT = 0x1
  internal const val OPCODE_BINARY = 0x2

    !!! tip
        Prefer to use the `Annotated` version if possible.

    ```Python hl_lines="20"
    {!> ../../../docs_src/dependencies/tutorial011.py!}
    ```

!!! tip
    All this might seem contrived. And it might not be very clear how is it useful yet.

    These examples are intentionally simple, but show how it all works.