assert response.status_code == 200, response.text
    assert response.json() == {
        "openapi": "3.1.0",
        "info": {
            "title": "Custom title",
            "summary": "This is a very custom OpenAPI schema",
            "description": "Here's a longer description of the custom **OpenAPI** schema",
            "version": "2.5.0",
            "x-logo": {

@app.middleware("http")
async def custom_middleware(
    request: Request, call_next: Callable[[Request], Awaitable[Response]]
):
    response = await call_next(request)
    response.headers["custom"] = "foo"
    return response


@app.get("/user", dependencies=[Depends(set_up_request_state_dependency)])
def get_user():
    request_state = legacy_request_state_context_var.get()
    assert request_state

///

## Custom Headers { #custom-headers }

Keep in mind that custom proprietary headers can be added <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">using the `X-` prefix</a>.

        "uid": "${DS_PROMETHEUS}"
      },
      "description": "",
      "fieldConfig": {
        "defaults": {
          "color": {
            "mode": "palette-classic"
          },
          "custom": {
            "axisBorderShow": false,
            "axisCenteredZero": false,
            "axisColorMode": "text",
            "axisLabel": "",
            "axisPlacement": "auto",
            "barAlignment": 0,

## Install custom exception handlers { #install-custom-exception-handlers }

You can add custom exception handlers with <a href="https://www.starlette.dev/exceptions/" class="external-link" target="_blank">the same exception utilities from Starlette</a>.

Let's say you have a custom exception `UnicornException` that you (or a library you use) might `raise`.

And you want to handle this exception globally with FastAPI.

        "type": "prometheus",
        "uid": "${DS_PROMETHEUS}"
      },
      "fieldConfig": {
        "defaults": {
          "color": {
            "mode": "palette-classic"
          },
          "custom": {
            "axisBorderShow": false,
            "axisCenteredZero": false,
            "axisColorMode": "text",
            "axisLabel": "",
            "axisPlacement": "auto",
            "barAlignment": 0,

                .put("analysis.analyzer.test_reading_term_analyzer.tokenizer", "standard")
                .put("analysis.analyzer.test_reading_analyzer_ja.type", "custom")
                .put("analysis.analyzer.test_reading_analyzer_ja.tokenizer", "keyword")
                .put("analysis.analyzer.test_reading_term_analyzer_ja.type", "custom")

    - topic_repos: ../en/data/topic_repos.yml
  redirects:
    redirect_maps:
      deployment/deta.md: deployment/cloud.md
      advanced/graphql.md: how-to/graphql.md
      advanced/custom-request-and-route.md: how-to/custom-request-and-route.md
      advanced/conditional-openapi.md: how-to/conditional-openapi.md
      advanced/extending-openapi.md: how-to/extending-openapi.md

 + .custom-select,\n.input-group > .form-control-plaintext + .custom-file,\n.input-group > .custom-select + .form-control,\n.input-group > .custom-select + .custom-select,\n.input-group > .custom-select + .custom-file,\n.input-group > .custom-file + .form-control,\n.input-group > .custom-file + .custom-select,\n.input-group > .custom-file + .custom-file {\n  margin-left: -1px;\n}\n\n.input-group > .form-control:focus,\n.input-group > .custom-select:focus,\n.input-group > .custom-file .custom-file-input:focus...

- **Features**: JavaScript rendering, authentication, custom headers

**File Crawling**:
- **Admin Path**: Crawler > File
- **Supports**: SMB, FTP, local file systems
- **Features**: Access control, file type filtering

**Data Store Crawling**:
- **Admin Path**: Crawler > Data Store
- **Supports**: Databases (via JDBC), CSV files, custom plugins
- **Features**: Incremental updates, custom field mapping

---