Files
mizan/backends/mizan-django
Ryth Azhur 45bde51166 Mizan-Rust backend adapter: server-side substrate + three-way parity
Adds first-class Rust-backed Mizan to sit alongside mizan-django and
mizan-fastapi. A Rust dev writes:

    #[derive(Mizan, Serialize, Deserialize)]
    pub struct ProfileOutput { pub user_id: i64, pub name: String }

    #[mizan::context("user")]
    pub struct UserCtx;

    #[mizan::client(context = UserCtx)]
    pub async fn user_profile(_req: &RequestHandle<'_>, user_id: i64) -> ProfileOutput { ... }

…and gets byte-identical KDL to the Python emitters, served over the
same wire protocol the React / Rust / Vue / Svelte kernels speak.

New crates:
- cores/mizan-rust/         (Cargo: mizan-core)     — IR types, KDL emitter, traits, registry,
                                                       runtime (compute_invalidation / compute_merges
                                                       ported from mizan-fastapi), graph_check with
                                                       structural type-matching
- cores/mizan-rust-macros/  (Cargo: mizan-macros)   — #[derive(Mizan)], #[mizan::context],
                                                       #[mizan::client] proc macros
- backends/mizan-rust-axum/ (Cargo: mizan-axum)     — axum HTTP adapter: /session/, /call/, /ctx/:name/
- tests/afi/rust_app/                                — AFI fixture port + server / export-ir binaries

Substrate-shape moves required by cross-language equivalence:
- IR canonicalization: functions / contexts / context-members / shared-by
  now sort alphabetically in both Python and Rust emitters. The IR is a
  contract; linkme doesn't preserve declaration order, so canonical sort
  is the only stable mapping. afi_ir.kdl + per-target baselines regenerated.
- MizanType::TYPE_NAME is a const (with a default type_name() reader) so
  it's usable in linkme TypeEntry static initializers.
- Tree-shaken type registry: #[derive(Mizan)] only emits the trait impl;
  the #[mizan::client] macro registers canonical-named entries from
  fn signatures, including Vec<T> element types for ref resolution.
- Merge resolution is structural (NamedType shape comparison) rather than
  by name — matches the Python types_match_for_merge semantics.

Three-way forcing functions:
- tests/afi/test_codegen_parity.py — Django ≡ FastAPI ≡ Rust on KDL bytes (3 pass)
- tests/rust/run_wire_parity.py    — 12/12 probes against FastAPI + Rust (EXIT=0)

Incidental fixes surfaced by the new tests:
- Stale `from .registry import validate_registry` import removed from
  mizan-django/setup/discovery.py (referenced a function that no longer
  exists; was masking codegen-parity).
- BASE_DIR added to tests/afi/django_app/project/settings.py.
- /session/ endpoint added to mizan-fastapi for protocol-shaped readiness
  probe parity (wire-parity harness now polls /api/mizan/session/ on both
  backends rather than FastAPI's /openapi.json).
- Root .gitignore picks up Rust target/ across the tree so new crates
  don't need per-crate gitignore.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-17 22:31:26 -04:00
..

mizan-django

Django backend adapter for the Mizan protocol. One decorator on a server function. Typed React client generated. Invalidation automatic.

Install

uv add "mizan[channels]"
# or with allauth integration:
uv add "mizan[channels,allauth]"

Setup

# settings.py
INSTALLED_APPS = ["mizan", "myapp", ...]

MIZAN_CACHE_SECRET   = "..."   # 32-byte HMAC signing key
MIZAN_CACHE_REDIS_URL = "redis://localhost:6379/0"
MIZAN_MWT_SECRET     = "..."   # MWT signing key (separate from cache + JWT)
# urls.py
from django.urls import include, path

urlpatterns = [
    path("api/mizan/", include("mizan.urls")),
]
# asgi.py — for WebSocket / Channels support
from django.core.asgi import get_asgi_application
from mizan import wrap_asgi

application = wrap_asgi(get_asgi_application())

Define server functions

# myapp/clients.py
from mizan.client import client
from mizan.setup import register
from pydantic import BaseModel


class EchoOutput(BaseModel):
    message: str


@client
def echo(request, text: str) -> EchoOutput:
    return EchoOutput(message=text)


register(echo, "echo")

Auto-discover clients.py modules from each Django app:

# myapp/apps.py
from django.apps import AppConfig


class MyAppConfig(AppConfig):
    name = "myapp"

    def ready(self) -> None:
        from mizan.setup import mizan_clients
        mizan_clients("myapp")  # imports myapp/clients.py — triggers @client side effects

@client parameters

@client                              # plain RPC function
@client(context="global")            # singleton context — fetched once, SSR-hydrated
@client(context="user")              # named context — fetched per provider mount
@client(affects="user")              # mutation — invalidates the user context
@client(affects=user_profile)        # mutation — invalidates a specific function
@client(websocket=True)              # WebSocket transport (requires channels)
@client(auth=True)                   # requires authentication
@client(auth="staff")                # requires is_staff
@client(auth="superuser")            # requires is_superuser
@client(auth=lambda req: ...)        # custom predicate
@client(route="/profile/<id>/")      # view-path function (returns HttpResponse)
@client(rev=2)                       # cache revision (busts on bump)

Forms

Django Forms become server functions + typed React hooks with Zod validation:

from django import forms
from mizan.forms import mizanFormMixin, mizanFormMeta


class ContactForm(mizanFormMixin, forms.Form):
    mizan = mizanFormMeta(name="contact", title="Contact Us", submit_label="Send")

    name    = forms.CharField()
    email   = forms.EmailField()
    message = forms.CharField(widget=forms.Textarea)

    def on_submit_success(self, request):
        send_email(self.cleaned_data)
        return {"sent": True}

Auto-registers contact.schema, contact.validate, contact.submit. Frontend gets useContactForm().

Channels

WebSocket-native RPC via a flag flip:

from pydantic import BaseModel
from mizan.channels import ReactChannel


class ChatChannel(ReactChannel):
    class Params(BaseModel):
        room: str

    class DjangoMessage(BaseModel):
        text: str
        user: str

    def authorize(self, params):
        return self.user.is_authenticated

    def group(self, params):
        return f"chat_{params.room}"

Frontend gets useChatChannel({ room }).

Generate the frontend

The codegen is mizan-generate (in protocol/mizan-generate/). From your frontend project, point a config at the Django backend and run the CLI:

// frontend/django.config.mjs
import path from "path"
import { fileURLToPath } from "url"

const __dirname = path.dirname(fileURLToPath(import.meta.url))
const root = path.resolve(__dirname, "..")

export default {
    source: {
        django: {
            managePath: path.join(root, "backend/manage.py"),
            command: ["uv", "run", "python"],
            env: {
                PYTHONPATH: path.join(root, "backend"),
                DJANGO_SETTINGS_MODULE: "myproject.settings",
            },
        },
    },
    output: "src/api",
}
npx mizan-generate --config django.config.mjs

The codegen drives Django's management command (export_mizan_schema) under the hood, then emits Stage 1 (typed callXxx/fetchXxx over the runtime kernel) + Stage 2 (<MizanContext> provider, per-context providers, use{Hook}() hooks) into src/api/.

// app.tsx
import { MizanContext } from "./api"

export default function App({ children }) {
    return <MizanContext baseUrl="/api/mizan">{children}</MizanContext>
}
// any component
import { useEcho, useCurrentUser } from "./api"

const echo = useEcho()
echo.mutate({ text: "hi" }).then(r => console.log(r.message))

const user = useCurrentUser()  // global context — auto-fetched, auto-refreshed on mutation

Running tests

uv sync --extra dev --extra channels
uv run pytest

Architecture

mizan-django is one of two reference backend adapters (the other is backends/mizan-fastapi). Both implement the same Mizan protocol on top of the shared cores/mizan-python core (@client, registry, MWT, HMAC cache keys). See docs/AFI_ARCHITECTURE.md.