reflex-dev/reflex v0.10.1a1

on GitHub

Breaking Changes

• router.session.client_ip now ignores untrusted X-Forwarded-For headers by default. Configure trusted_proxy_hops to use forwarded client addresses from a trusted proxy chain. (#7614)

Features

• Add an experimental, default-off react_compiler configuration flag to enable React Compiler memoization for generated components in development and production. (#7234)

• Form on_submit handlers can annotate their form data as rx.form.FormData to receive every value of fields that share a name, in submission order; a dict annotation still keeps each name's last value. In a TypedDict annotation, a list[str] field collects every value of its name and a bool field is False when nothing was submitted, such as for an unchecked checkbox, or when the value is false-like, such as "false", "off" or "0"; for list[str] | None and bool | None fields an unsubmitted value is None, and an unsubmitted NotRequired field is left out. In a TypedDict, a list field range also collects the range[] values a two-thumb rx.slider(name="range") submits.

  @rx.event
  def handle_submit(self, form_data: rx.form.FormData[str, str]):
      self.toppings = form_data.getlist("topping")
  ``` ([#7386](https://github.com/reflex-dev/reflex/issues/7386))

• A page's on_load accepts any sequence of events, e.g. a tuple, like a list of them. (#7402)

• Detect a frontend built for another version of the app when it connects to the backend. The compiled frontend now carries a hash of the state tree (state names, frontend vars and event handler names) and sends it on every socket connect. On a mismatch, a production page reloads once (sharing the REFLEX_AUTO_RELOAD_COOLDOWN with the reload on frontend errors) and otherwise shows a "new version available" banner with a reload button; in dev mode it only logs a console warning. Load balancers serving several backend versions still need sticky sessions. (#7553)

• Expose rx.moment_provider for sharing locale, timezone, formatting, and timer defaults across Moment components. (#7591)

Bug Fixes

• Use atomic writes and OS locks to protect shared JSON metadata from concurrent Reflex processes. When locks are unavailable (for example, with a read-only REFLEX_DIR), writes remain atomic but concurrent updates may overwrite each other. (#7052)
• Load backend apps by their configured module name so state updates work even when the app package has no __init__.py. (#7258)
• A stateful_pages.json marker that is not valid UTF-8 is now treated as corrupt and rebuilt, instead of raising UnicodeDecodeError on every backend start. (#7404)
• Type checkers see the database helpers of reflex.model (rx.session, rx.asession, rx.Model, ModelRegistry, ...) as defined, rather than as unions with the stand-ins used when the db extra is missing. (#7406)
• Fix a global rx._x.client_state reader that mounts after the value was set, such as one behind an rx.cond, keeping the stale value when the value is later set back to its default. (#7407)
• Fix TypeError: refs._client_state_set... is not a function when the backend pushes a global rx._x.client_state value before any component using it has mounted, such as one behind an rx.cond or a page that waits for hydration. The value is now kept for the first component that mounts. (#7407)
• Fix unawaited coroutine warnings when a state delta filter withholds an async uncached computed variable. (#7410)
• Fix installing Reflex source distributions with uv by excluding references to workspace packages that are not included in the archive. (#7411)
• Cancel unfinished page-load event chains when the client disconnects, including hydration that has not yet started. Independent background events continue running. (#7415)
• The backend log for an unknown frontend substate now says the substate was skipped instead of reporting a failed state update. The frontend exception handler docs describe how to resolve the mismatch. (#7435)
• reflex.model (and rx.ModelRegistry, rx.session, rx.Model) can be imported without greenlet, which SQLAlchemy 2.1 only installs with its asyncio extra; only rx.asession and get_async_engine require it now. (#7440)
• Detect state reads from the new shared state store when checking that an app that reads state defines an rx.State subclass. (#7441)
• Raise an actionable error when a legacy string passed to App.modify_state() has a missing or unknown state path. Use rx.BaseStateToken(ident=client_token, cls=StateClass) to select the state explicitly. (#7443)
• Production exports, reflex run --env prod, and preview startup that share a .web directory now wait for one another instead of overwriting each other's compiled frontend and archives. (#7453)
• Mutating a nested value reached through dict.values() or dict.items() on a state var now marks the var dirty, so the UI and cached vars depending on it update. (#7500)
• reflex run no longer logs "Unexpected exit from worker-1" when the dev backend is stopped with SIGTERM or SIGINT. (#7538)
• Cap the automatically selected number of Redis-backed backend workers at eight. Set GRANIAN_WORKERS to override the default. (#7542)
• reflex init no longer refuses to reinitialize an existing app just because its project directory is named reflex; the check now applies to the app_name set in rxconfig.py. (#7554)
• Add development frontend packages with -D, so npm saves them under devDependencies and source-only hot reloads no longer reinstall frontend packages. (#7566)
• Cached computed vars that depend on client storage (rx.LocalStorage, rx.SessionStorage, rx.Cookie) are now evaluated once per page load instead of twice. (#7568)
• A background task that re-enters an expired session now rehydrates the loaded state tree, so the browser no longer shows stale values for those states. (#7585)
• Repeated request headers are no longer collapsed to their last value: repeated cookie fields are joined with "; " and any other repeated field with ", ", so router.headers.cookie keeps every cookie. (#7588)
• Websocket connections now accept request header values containing bytes that are not valid UTF-8. (#7602)
• Avoid false type errors when hydrating or assigning strings to vars annotated with Cookie, LocalStorage, or SessionStorage. (#7603)
• Clarify the warning shown when Bun is below the minimum supported version. (#7639)

Performance

• Production backend workers on Linux are now forked from a supervisor that has already imported the app, so they share its memory instead of each importing the app again, which cuts memory use and startup time. Set REFLEX_BACKEND_START_METHOD=spawn for apps that are not fork-safe. (#7079)
• The reflex run backend reload worker is now forked from the supervisor on Linux instead of started through a forkserver, so framework code is shared copy-on-write and the extra forkserver processes are gone. Set REFLEX_BACKEND_START_METHOD=spawn or REFLEX_STRICT_HOT_RELOAD=1 for apps that are not fork-safe. (#7113)
• Speed up deployment archive creation by reducing filesystem checks for excluded files and avoiding recompression of precompressed frontend assets. (#7450)