### Small Errors Automatically Handled

When building web APIs with FastAPI, if there's an error in our code, FastAPI will normally contain it to the single request that triggered the error. 🛡

The client will get a **500 Internal Server Error** for that request, but the application will continue working for the next requests instead of just crashing completely.

import org.jetbrains.kotlin.types.KotlinType
import org.jetbrains.kotlin.types.TypeUtils
import org.jetbrains.kotlin.types.checker.intersectWrappedTypes
import org.jetbrains.kotlin.types.error.ErrorTypeKind
import org.jetbrains.kotlin.types.error.ErrorUtils
import org.jetbrains.kotlin.types.typeUtil.makeNullable

class KtFe10ExpressionTypeProvider(
    override val analysisSession: KtFe10AnalysisSession

## Accessing the request body in an exception handler

!!! tip
    To solve this same problem, it's probably a lot easier to use the `body` in a custom handler for `RequestValidationError` ([Handling Errors](../tutorial/handling-errors.md#use-the-requestvalidationerror-body){.internal-link target=_blank}).

    But this example is still valid and it shows how to interact with the internal components.

  // +listType=atomic
  // +optional
  repeated Validation validations = 3;

  // failurePolicy defines how to handle failures for the admission policy. Failures can
  // occur from CEL expression parse errors, type check errors, runtime errors and invalid
  // or mis-configured policy definitions or bindings.
  //
  // A policy is invalid if spec.paramKind refers to a non-existent Kind.

        dep -->> handler: Raise HTTPException
        handler -->> client: HTTP error response
        dep -->> dep: Raise other exception
    end
    dep ->> operation: Run dependency, e.g. DB session
    opt raise
        operation -->> dep: Raise HTTPException
        dep -->> handler: Auto forward exception
        handler -->> client: HTTP error response
        operation -->> dep: Raise other exception

* **Menos errores**: Reduce los errores humanos (de programador) aproximadamente un 40%. *
* **Intuitivo**: Gran soporte en los editores con <abbr title="conocido en inglés como auto-complete, autocompletion, IntelliSense, completion">auto completado</abbr> en todas partes. Gasta menos tiempo <abbr title="buscando y corrigiendo errores">debugging</abbr>.

        if [[ ! -f $target ]] && [[ ! -d $target ]]; then
            echo "$i" >> errors.txt
        fi
        if [[ -e errors.txt ]]; then
            echo "Broken links found:"
            cat errors.txt
            rm errors.txt
            false
        fi
    done
}

@test "No duplicate files on Windows" {
    cat <<EOF

 * that [get] was called. Updates and removals after the call do not impact ongoing reads.
 *
 * This class is tolerant of some I/O errors. If files are missing from the filesystem, the
 * corresponding entries will be dropped from the cache. If an error occurs while writing a cache
 * value, the edit will fail silently. Callers should handle other problems by catching
 * `IOException` and responding appropriately.
 *

]
context = '${CONTEXT}'
omit = [
    "docs_src/response_model/tutorial003_04.py",
    "docs_src/response_model/tutorial003_04_py310.py",
]

[tool.ruff.lint]
select = [
    "E",  # pycodestyle errors
    "W",  # pycodestyle warnings
    "F",  # pyflakes
    "I",  # isort
    "B",  # flake8-bugbear
    "C4",  # flake8-comprehensions
    "UP",  # pyupgrade
]
ignore = [

enum class ErrorCode constructor(val httpCode: Int) {
  /** Not an error!  */
  NO_ERROR(0),

  PROTOCOL_ERROR(1),

  INTERNAL_ERROR(2),

  FLOW_CONTROL_ERROR(3),

  SETTINGS_TIMEOUT(4),

  STREAM_CLOSED(5),

  FRAME_SIZE_ERROR(6),

  REFUSED_STREAM(7),

  CANCEL(8),

  COMPRESSION_ERROR(9),

  CONNECT_ERROR(0xa),

  ENHANCE_YOUR_CALM(0xb),

  INADEQUATE_SECURITY(0xc),