Define a schema from Rust

Prerequisites

panproto-core in your Cargo.toml (Install the Rust SDK).

The task

use panproto_core::protocols::atproto;
use panproto_core::schema::SchemaBuilder;

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let proto = atproto::protocol();

    let schema = SchemaBuilder::new(&proto)
        .vertex("user", "object", Some("app.example.user"))?
        .vertex("user:name", "string", None)?
        .vertex("user:age", "integer", None)?
        .edge("user", "user:name", "prop", Some("name"))?
        .edge("user", "user:age", "prop", Some("age"))?
        .entry("user")
        .build()?;

    println!("{} vertices, {} edges", schema.vertices.len(), schema.edges.len());
    Ok(())
}

SchemaBuilder::new(&protocol) constructs the builder; each vertex and edge call validates against the protocol’s edge rules and obj-kind list. entry declares basepoint vertices for instance rooting. build returns a Schema (or a SchemaError).

Verification

use panproto_core::schema::{SchemaBuilder, validate};
fn main() -> Result<(), Box<dyn std::error::Error>> {
let proto = panproto_core::protocols::atproto::protocol();
let schema = SchemaBuilder::new(&proto)
    .vertex("user", "object", Some("app.example.user"))?
    .entry("user")
    .build()?;
let errors = validate(&schema, &proto);
assert!(errors.is_empty(), "validation errors: {errors:?}");
Ok(()) }

validate returns a Vec<ValidationError>. The error carries the failing equation and the offending vertex or edge as structured fields.

Common mistakes

• Reaching past panproto-core to lower-level crates without a reason. The facade re-exports the canonical surface; do not depend on panproto-schema directly unless you need an internal API.
• Holding Schema across an await. Handles are not Send by default; clone them or restructure the call.

See also

• Reference: Rust SDK.
• docs.rs for panproto-core.
• Build a migration.