Capabilities

Capabilities are declarations of what your app needs to do. Today they cover databases — declaring a database capability tells the runtime which provider to wire up and how the app intends to use it.

const builder = Sloppy.createBuilder();

builder.capabilities.addDatabase("data.main", {
    provider: "sqlite",
    access: "readwrite",
});

const app = builder.build();

The capability "data.main" is then available to services and handlers via app.capabilities / ctx.capabilities.

Declaring a database capability

builder.capabilities.addDatabase(token, {
    provider: "sqlite" | "postgres" | "sqlserver",
    access:   "read" | "write" | "readwrite",
});

Field	Notes
provider	Provider implementation backing the capability
access	Maximum access the capability grants

The token is a free-form string. Convention is dotted lowercase ("data.main", "data.replicas.eu"). Tokens are how data.* calls find the capability:

const main = ctx.services.get("data.main");
// or open a provider directly with a capability reference:
//   data.sqlite.open({ capability: "data.main", database: ":memory:" });

Reading capabilities

const cap = app.capabilities.get("data.main");
// {
//   token:     "data.main",
//   kind:      "database",
//   provider:  "sqlite",
//   access:    "readwrite",
//   metadata:  {},
//   module:    null,
// }

app.capabilities.list();
// [...all declared capabilities]

Module capabilities

A module can declare its own capabilities. They merge into the app's capability set with the module name attached:

const Users = Sloppy.module("users")
    .capabilities((caps) => {
        caps.addDatabase("data.users", {
            provider: "sqlite",
            access: "readwrite",
        });
    });

app.useModule(Users);
app.capabilities.get("data.users").module === "users";

What capabilities are not

• Not an OS sandbox. The runtime checks capabilities before opening resources, but it doesn't constrain the rest of the process.
• Not an authorization system. Capabilities describe what the app declares about itself, not what end users can do.

What's planned

Filesystem and network capabilities are planned (addFs, addNetwork). Today, only addDatabase is wired up.