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Sillo

Inertia

Build a React or Vue front end against Sillo routes with sillo-inertia: server-side routing, no API layer, and no client-side router to keep in sync.

Inertia

Section titled “Inertia”

Inertia.js lets you write a React or Vue front end without building an API for it. Routes stay on the server, handlers return a component name and its props, and the client swaps the page without a full reload.

A handler names a component and returns its props:

from sillo import HttpContext


@app.get("/dashboard")
async def dashboard(ctx: HttpContext):
    return await render("Dashboard", {"stats": {"signed_in_as": ctx.user.email}})

The component receives them as props:

export default function Dashboard({ stats }: Props) {
  return <p>Signed in as {stats.signed_in_as}</p>
}

There is no endpoint to define, no client-side fetch, no loading state, and no second description of the same data.

Where it sits

Section titled “Where it sits”

It is the middle path between a server-rendered page and a SPA: you get a real component-based front end, but routing, authorisation and data loading stay in Python, where the rest of your application already is.

RoutingData reaches the page byYou also maintain
Server-rendered HTMLServerTemplate contextNothing
InertiaServerProps, with the pageComponents
SPAClientfetch from an APIComponents, a router, an API

Choose plain HTML when the page is mostly content — Sillo has no template engine of its own in 1.0, so that means a library of your choosing. Choose a SPA when something other than your own front end consumes the API: a mobile client, a partner integration. Choose Inertia when you want components and there is exactly one consumer.

How a page renders

Section titled “How a page renders”

Your handler is the same either way. What the response is gets decided by the request:

  • First visit. A browser navigation. The response is the full HTML shell with the page object embedded, so the document has a title and content before any JavaScript runs.
  • Every navigation after: an XHR carrying X-Inertia. The response is the page object as JSON, and the client swaps it into the page already open.

This is why Inertia pages are excluded from the OpenAPI document. A GET /login that returns an HTML document to a browser and a JSON page object to Inertia is not an API endpoint, and describing it as one (“Successful Response”, application/json) is worse than not describing it at all.

Installing

Section titled “Installing”

Support lives in a separate package, so nothing here is carried by applications that do not use it.

Terminal window
uv add sillo-inertia

The starter has it wired already, along with Vite, React, Tailwind and a working auth flow. Starting there is the shortest path to a running page.

This section

Section titled “This section”
Section titled “Related”

Getting Started

Introduction Philosophy FAQ Coming from FastAPI & Django What's in the Box Installation Request Lifecycle

Core Concepts

Configuration Environment & .env Routing Routers & Sub-Apps Handlers Middleware Dependency Injection URL Normalization Request Information Handling Inputs Request Parameters Headers Cookies File Uploads Content Negotiation Sending Responses JSON Serialization Streaming Responses Pagination Error Handling

Building an Application

Creating a Project Project Structure The Console Database & Migrations Users & Authentication Background Work Testing Deployment

Validation

Overview Parameters Request Bodies Forms & File Uploads Response Models Validation Errors Generated Docs

Deep Dive

Startup & Shutdown Concurrency & Thread Pool Caching Storage Event System OpenAPI Overview Documentation UI OpenAPI Parameters OpenAPI Request Schemas OpenAPI Response Models OpenAPI Auth Docs OpenAPI Customization Background Work Overview Background Tasks Queues Jobs Scheduler Event Dispatcher WebSockets Overview WebSocket Events Static Files Frontend (SPA) HTTP Client Mail Service Console Commands

Helpers

Overview Async Crypto Deprecation Files Hashing HTML JWT Network Retry Strings Text

Authentication & Authorization

Overview Users & User Models Password Hashing Protecting Routes Permissions JWT Authentication Session Authentication API Keys

OAuth2 & Social Login

OAuth2 Overview OAuth Providers Persisting the Login OAuth in OpenAPI The Security Model

Security

Security Headers CORS CSRF Protection Rate Limiting Session Management