Extractors

Dioxus fullstack integrates with Axum extractors to access request data in server functions. You can extract headers, cookies, query parameters, and more from the incoming HTTP request.

Extracting Request Data

Use FullstackContext::extract() to extract Axum types inside server functions:

use dioxus::prelude::*;
use dioxus::fullstack::FullstackContext;
use dioxus::server::axum::{Extension, TypedHeader};
use headers::{Authorization, Bearer};

#[server]
async fn protected_resource() -> Result<String> {
    // Extract typed header
    let TypedHeader(auth): TypedHeader<Authorization<Bearer>> = 
        FullstackContext::extract().await?;
    
    // Extract extension data
    let Extension(db): Extension<Database> = 
        FullstackContext::extract().await?;
    
    Ok(format!("Authorized with token: {}", auth.token()))
}

FullstackContext

The FullstackContext provides access to the current HTTP request context on the server.

pub struct FullstackContext { /* ... */ }

Location: packages/fullstack-core/src/streaming.rs:17

Methods

`current()`

pub fn current() -> Option<Self>

Get the current FullstackContext if available. Returns None on the client or outside a request context. Location: packages/fullstack-core/src/streaming.rs:156 Example:

if let Some(ctx) = FullstackContext::current() {
    // We're on the server
    ctx.add_response_header("X-Custom", "value");
}

`extract()`

pub async fn extract<T: FromRequest<Self, M>, M>() -> Result<T, ServerFnError>

Extract an Axum extractor from the current request. Location: packages/fullstack-core/src/streaming.rs:128 Example:

use dioxus::server::axum::Extension;

#[server]
async fn use_extension() -> Result<String> {
    let Extension(config): Extension<AppConfig> = 
        FullstackContext::extract().await?;
    Ok(config.name.clone())
}

`extension()`

pub fn extension<T: Clone + Send + Sync + 'static>(&self) -> Option<T>

Get an extension from the request without using async. Location: packages/fullstack-core/src/streaming.rs:119 Example:

if let Some(ctx) = FullstackContext::current() {
    if let Some(user_id) = ctx.extension::<UserId>() {
        // Use user_id
    }
}

`parts_mut()`

pub fn parts_mut(&self) -> RwLockWriteGuard<'_, http::request::Parts>

Access the raw HTTP request parts mutably. Location: packages/fullstack-core/src/streaming.rs:106 Example:

let ctx = FullstackContext::current().unwrap();
let mut parts = ctx.parts_mut();
println!("Method: {}", parts.method);
println!("URI: {}", parts.uri);

`add_response_header()`

pub fn add_response_header(
    &self,
    key: impl Into<HeaderName>,
    value: impl Into<HeaderValue>,
)

Add a header to the HTTP response. Location: packages/fullstack-core/src/streaming.rs:196 Example:

#[server]
async fn with_custom_header() -> Result<String> {
    if let Some(ctx) = FullstackContext::current() {
        ctx.add_response_header("X-Custom-Header", "my-value");
    }
    Ok("Response with custom header".into())
}

`commit_http_status()`

pub fn commit_http_status(status: StatusCode, message: Option<String>)

Set the HTTP status code for the response. Location: packages/fullstack-core/src/streaming.rs:216 Example:

#[server]
async fn not_found() -> Result<String> {
    FullstackContext::commit_http_status(
        http::StatusCode::NOT_FOUND,
        Some("Resource not found".into()),
    );
    Ok(String::new())
}

Common Extractors

TypedHeader

Extract typed headers using the headers crate:

use dioxus::server::axum::TypedHeader;
use headers::{Authorization, Bearer, UserAgent, ContentType};

#[server]
async fn get_headers() -> Result<String> {
    // Authorization header
    let TypedHeader(auth): TypedHeader<Authorization<Bearer>> = 
        FullstackContext::extract().await?;
    
    // User-Agent header
    let TypedHeader(user_agent): TypedHeader<UserAgent> = 
        FullstackContext::extract().await?;
    
    Ok(format!("Token: {}, UA: {}", auth.token(), user_agent.as_str()))
}

Common header types:

Authorization<Bearer> - Authorization: Bearer token
ContentType - Content-Type header
UserAgent - User-Agent string
Cookie - HTTP cookies
Host - Host header
Referer - Referer header

Extension

Extract shared state added via Axum extensions:

use dioxus::server::axum::{self, Extension};

#[derive(Clone)]
struct Database { /* ... */ }

#[derive(Clone)]
struct CurrentUser {
    id: u32,
    name: String,
}

fn main() {
    dioxus::serve(|| async move {
        let db = Database::connect().await?;
        
        let router = axum::Router::new()
            .serve_dioxus_application(ServeConfig::new(), app)
            .layer(Extension(db));
        
        Ok(router)
    });
}

#[server]
async fn query_db() -> Result<Vec<User>> {
    let Extension(db): Extension<Database> = 
        FullstackContext::extract().await?;
    
    db.query("SELECT * FROM users").await
}

#[server]
async fn get_current_user() -> Result<String> {
    let Extension(user): Extension<CurrentUser> = 
        FullstackContext::extract().await?;
    
    Ok(user.name)
}

Query

Extract query parameters from the URL:

use dioxus::fullstack::Query;
use serde::Deserialize;

#[derive(Deserialize)]
struct SearchParams {
    q: String,
    page: Option<u32>,
    limit: Option<u32>,
}

#[server]
async fn search() -> Result<Vec<String>> {
    let Query(params): Query<SearchParams> = 
        FullstackContext::extract().await?;
    
    let page = params.page.unwrap_or(1);
    let limit = params.limit.unwrap_or(10);
    
    Ok(vec![format!("Searching for: {} (page {})", params.q, page)])
}

Location: packages/fullstack/src/payloads/query.rs:12 The Query extractor uses serde_qs to support complex query structures.

Form and Multipart

Extract form data:

use dioxus::fullstack::{Form, Multipart};
use serde::Deserialize;

#[derive(Deserialize)]
struct LoginForm {
    username: String,
    password: String,
}

#[server]
async fn login(form: Form<LoginForm>) -> Result<String> {
    let LoginForm { username, password } = form.0;
    // Validate credentials
    Ok(format!("Logged in as {}", username))
}

#[server]
async fn upload(multipart: Multipart) -> Result<String> {
    // Process file upload
    Ok("File uploaded".into())
}

Cookies

Extract cookies from the request:

use dioxus::server::axum::TypedHeader;
use headers::Cookie;

#[server]
async fn get_session() -> Result<String> {
    let TypedHeader(cookies): TypedHeader<Cookie> = 
        FullstackContext::extract().await?;
    
    if let Some(session_id) = cookies.get("session_id") {
        Ok(format!("Session: {}", session_id))
    } else {
        Err(ServerFnError::new("No session cookie"))
    }
}

JSON Body

Extract and deserialize JSON from the request body:

use dioxus::server::axum::Json;
use serde::{Deserialize, Serialize};

#[derive(Deserialize, Serialize)]
struct CreateUser {
    name: String,
    email: String,
}

#[server]
async fn create_user(Json(data): Json<CreateUser>) -> Result<Json<CreateUser>> {
    // Save to database
    Ok(Json(data))
}

Custom Extractors

You can create custom extractors by implementing FromRequest:

use axum_core::extract::{FromRequest, Request};
use dioxus::fullstack::FullstackContext;

struct CurrentUser {
    id: u32,
    name: String,
}

#[async_trait::async_trait]
impl FromRequest<FullstackContext> for CurrentUser {
    type Rejection = ServerFnError;
    
    async fn from_request(
        req: Request,
        state: &FullstackContext,
    ) -> Result<Self, Self::Rejection> {
        // Extract and validate JWT token
        let TypedHeader(auth): TypedHeader<Authorization<Bearer>> = 
            TypedHeader::from_request(req, state).await
                .map_err(|_| ServerFnError::new("Missing authorization"))?;
        
        // Decode token
        let user = decode_jwt(auth.token())?;
        
        Ok(user)
    }
}

#[server]
async fn protected_endpoint() -> Result<String> {
    let user: CurrentUser = FullstackContext::extract().await?;
    Ok(format!("Hello, {}!", user.name))
}

Request Guards

Combine extractors for authorization:

use http::StatusCode;

struct AdminUser(CurrentUser);

#[async_trait::async_trait]
impl FromRequest<FullstackContext> for AdminUser {
    type Rejection = StatusCode;
    
    async fn from_request(
        req: Request,
        state: &FullstackContext,
    ) -> Result<Self, Self::Rejection> {
        let user: CurrentUser = CurrentUser::from_request(req, state)
            .await
            .map_err(|_| StatusCode::UNAUTHORIZED)?;
        
        if user.is_admin {
            Ok(AdminUser(user))
        } else {
            Err(StatusCode::FORBIDDEN)
        }
    }
}

#[server]
async fn admin_only() -> Result<String, StatusCode> {
    let AdminUser(user) = FullstackContext::extract().await
        .map_err(|_| StatusCode::FORBIDDEN)?;
    
    Ok(format!("Admin: {}", user.name))
}

Examples

Authentication Middleware

use dioxus::server::axum::{self, Extension, middleware};
use dioxus::fullstack::FullstackContext;

#[derive(Clone)]
struct AuthenticatedUser {
    id: u32,
    name: String,
}

async fn auth_middleware(
    TypedHeader(auth): TypedHeader<Authorization<Bearer>>,
    mut request: Request,
    next: middleware::Next,
) -> Result<Response, StatusCode> {
    let user = verify_token(auth.token())
        .await
        .map_err(|_| StatusCode::UNAUTHORIZED)?;
    
    request.extensions_mut().insert(user);
    Ok(next.run(request).await)
}

fn main() {
    dioxus::serve(|| async move {
        let router = axum::Router::new()
            .serve_dioxus_application(ServeConfig::new(), app)
            .layer(middleware::from_fn(auth_middleware));
        
        Ok(router)
    });
}

#[server]
async fn get_profile() -> Result<String> {
    let Extension(user): Extension<AuthenticatedUser> = 
        FullstackContext::extract().await?;
    
    Ok(user.name)
}

Database Connection Pool

use dioxus::server::axum::Extension;
use sqlx::{PgPool, FromRow};

#[derive(Clone)]
struct DbPool(PgPool);

#[derive(FromRow)]
struct User {
    id: i32,
    name: String,
}

fn main() {
    dioxus::serve(|| async move {
        let pool = PgPool::connect(&std::env::var("DATABASE_URL")?)
            .await?;
        
        let router = axum::Router::new()
            .serve_dioxus_application(ServeConfig::new(), app)
            .layer(Extension(DbPool(pool)));
        
        Ok(router)
    });
}

#[server]
async fn get_user(id: i32) -> Result<User> {
    let Extension(DbPool(pool)): Extension<DbPool> = 
        FullstackContext::extract().await?;
    
    let user = sqlx::query_as::<_, User>("SELECT * FROM users WHERE id = $1")
        .bind(id)
        .fetch_one(&pool)
        .await?;
    
    Ok(user)
}

Core

Hooks

Router

HTML Elements

Fullstack

Extracting Request Data

FullstackContext

Methods

`current()`

`extract()`

`extension()`

`parts_mut()`

`add_response_header()`

`commit_http_status()`

Common Extractors

TypedHeader

Extension

Query

Form and Multipart

Cookies

JSON Body

Custom Extractors

Request Guards

Examples

Authentication Middleware

Database Connection Pool

Build docs developers (and LLMs) love

Core

Hooks

Router

HTML Elements

Fullstack

​Extracting Request Data

​FullstackContext

​Methods

​current()

​extract()

​extension()

​parts_mut()

​add_response_header()

​commit_http_status()

​Common Extractors

​TypedHeader

​Extension

​Query

​Form and Multipart

​Cookies

​JSON Body

​Custom Extractors

​Request Guards

​Examples

​Authentication Middleware

​Database Connection Pool

Build docs developers (and LLMs) love

Extracting Request Data

FullstackContext

Methods

`current()`

`extract()`

`extension()`

`parts_mut()`

`add_response_header()`

`commit_http_status()`

Common Extractors

TypedHeader

Extension

Query

Form and Multipart

Cookies

JSON Body

Custom Extractors

Request Guards

Examples

Authentication Middleware

Database Connection Pool