Struct RenderCtx 

pub struct RenderCtx { /* private fields */ }

What a render takes beyond PageConfig: the policy’s typed extensions, the walk’s budgets, and the typed homes for what applications used to put in body_prefix: the route’s modulepreload links from the build’s manifest, and head links. Never a nonce: the render draws one per response. Data goes through PageConfig::config_json.

use forma_server::{HeadLink, PolicyExtensions, RenderCtx, WalkLimits};

let ctx = RenderCtx::new()
    .with_policy(PolicyExtensions::new().img_src("https:"))
    .with_limits(WalkLimits { max_list_iterations: 100_000, ..WalkLimits::default() })
    .with_head_link(HeadLink::new("icon", "/favicon.svg")?);

Implementations

impl RenderCtx

pub fn new() -> Self

The strict policy and the walker’s default budgets (8 MiB of output, 50,000 list rows).

pub fn with_policy(self, policy: PolicyExtensions) -> Self

Extend this page’s policy (see PolicyExtensions).

pub fn with_limits(self, limits: WalkLimits) -> Self

Budget this page’s walk differently from the defaults.

pub fn with_module_preloads(self, preloads: &ModulePreloads) -> Self

Write the route’s modulepreload links from the build’s manifest, each with the page’s nonce, after the route’s own modules. The typed home for a preload workaround in body_prefix, such as Ledger’s. The table covers every route; the render takes config.route_pattern’s list. Like every typed home, each call site belongs on the application’s raw-entry allowlist (forma-raw-lint).

use forma_server::{assets, ModulePreloads, RenderCtx};

// At start, beside the manifest; refuse to start on its error.
fn start<Assets: rust_embed::Embed>() -> Result<ModulePreloads, String> {
    assets::try_load_module_preloads::<Assets>()
}

// Per request.
fn ctx(preloads: &ModulePreloads) -> RenderCtx {
    RenderCtx::new().with_module_preloads(preloads)
}

Verified by: crates/forma-server/tests/typed_homes.rs > “try_render_writes_the_routes_manifest_modulepreload_links_nonced”

pub fn with_head_link(self, link: HeadLink) -> Self

Add a <link> to the page’s head (see HeadLink), after any added before it. The typed home for links spliced in before </head>; each call site belongs on the application’s raw-entry allowlist (forma-raw-lint).

Verified by: crates/forma-server/tests/typed_homes.rs > “head_links_are_written_escaped_in_the_head_in_the_order_added”

Trait Implementations

impl Clone for RenderCtx

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for RenderCtx

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for RenderCtx

fn default() -> Self

Returns the “default value” for a type.