feat!: Use schema stuff in the capabilities instead of custom parsing

packages/interface/src/capability.ts

@@ -12,13 +12,11 @@ import {
   Await,
   IssuedInvocationView,
   UCANOptions,
-  DIDKey,
   Verifier,
-  API,
 } from './lib.js'
 
 export interface Source {
-  capability: Capability
+  capability: { can: Ability; with: URI; nb?: Caveats }
   delegation: Delegation
   index: number
 }
@@ -67,7 +65,7 @@ export interface Reader<
 }
 
 export interface Caveats {
-  [key: string]: Reader<any, unknown>
+  [key: string]: unknown
 }
 
 export type MatchResult<M extends Match> = Result<M, InvalidCapability>
@@ -80,17 +78,12 @@ export type InvalidCapability = UnknownCapability | MalformedCapability
 export interface DerivedMatch<T, M extends Match>
   extends Match<T, M | DerivedMatch<T, M>> {}
 
-export interface DeriveSelector<M extends Match, T extends ParsedCapability> {
-  to: TheCapabilityParser<DirectMatch<T>>
-  derives: Derives<ToDeriveClaim<T>, ToDeriveProof<M['value']>>
-}
-
 /**
  * Utility type is used to infer the type of the capability passed into
- * `derives` handler. It simply makes all `nb` fileds optional because
+ * `derives` handler. It simply makes all `nb` fields optional because
  * in delegation all `nb` fields could be left out implying no restrictions.
  */
-export type ToDeriveClaim<T extends ParsedCapability> =
+type ToDeriveClaim<T extends ParsedCapability> =
   | T
   | ParsedCapability<T['can'], T['with'], Partial<T['nb']>>
 
@@ -101,18 +94,18 @@ export type ToDeriveClaim<T extends ParsedCapability> =
  * all `nb` fields optional, because in delegation all `nb` fields could be
  * left out implying no restrictions.
  */
-export type ToDeriveProof<T> = T extends ParsedCapability
+export type InferDeriveProof<T> = T extends ParsedCapability
   ? // If it a capability we just make `nb` partial
-    ToDeriveClaim<T>
+    InferDelegatedCapability<T>
   : // otherwise we need to map tuple
-    ToDeriveProofs<T>
+    InferDeriveProofs<T>
 
 /**
  * Another helper type which is equivalent of `ToDeriveClaim` except it works
  * on tuple of capabilities.
  */
-type ToDeriveProofs<T> = T extends [infer U, ...infer E]
-  ? [ToDeriveClaim<U & ParsedCapability>, ...ToDeriveProofs<E>]
+type InferDeriveProofs<T> = T extends [infer U, ...infer E]
+  ? [ToDeriveClaim<U & ParsedCapability>, ...InferDeriveProofs<E>]
   : T extends never[]
   ? []
   : never
@@ -154,33 +147,27 @@ export interface View<M extends Match> extends Matcher<M>, Selector<M> {
    * })
    * ```
    */
-  derive<T extends ParsedCapability>(
-    options: DeriveSelector<M, T>
-  ): TheCapabilityParser<DerivedMatch<T, M>>
+  derive<T extends ParsedCapability>(options: {
+    to: TheCapabilityParser<DirectMatch<T>>
+    derives: Derives<T, InferDeriveProof<M['value']>>
+  }): TheCapabilityParser<DerivedMatch<T, M>>
 }
 
-export type InferCaveatParams<T> = keyof T extends never
-  ? never | undefined
-  : {
-      [K in keyof T]: T[K] extends { toJSON(): infer U } ? U : T[K]
-    }
-
 export interface TheCapabilityParser<M extends Match<ParsedCapability>>
   extends CapabilityParser<M> {
   readonly can: M['value']['can']
 
   create(
     input: InferCreateOptions<M['value']['with'], M['value']['nb']>
-  ): M['value']
+  ): InferCapability<M['value']>
 
   /**
    * Creates an invocation of this capability. Function throws exception if
    * non-optional fields are omitted.
    */
-
   invoke(
     options: InferInvokeOptions<M['value']['with'], M['value']['nb']>
-  ): IssuedInvocationView<M['value']>
+  ): IssuedInvocationView<InferCapability<M['value']>>
 
   /**
    * Creates a delegation of this capability. Please note that all the
@@ -189,12 +176,31 @@ export interface TheCapabilityParser<M extends Match<ParsedCapability>>
    */
   delegate(
     options: InferDelegationOptions<M['value']['with'], M['value']['nb']>
-  ): Promise<Delegation<[ToDeriveClaim<M['value']>]>>
+  ): Promise<Delegation<[InferDelegatedCapability<M['value']>]>>
 }
 
+/**
+ * When normalize capabilities by removing `nb` if it is a `{}`. This type
+ * does that normalization at the type level.
+ */
+export type InferCapability<T extends ParsedCapability> =
+  keyof T['nb'] extends never
+    ? { can: T['can']; with: T['with'] }
+    : { can: T['can']; with: T['with']; nb: T['nb'] }
+
+/**
+ * In delegation capability all the `nb` fields are optional. This type maps
+ * capability type (as it would be in the invocation) to the form it will be
+ * in the delegation.
+ */
+export type InferDelegatedCapability<T extends ParsedCapability> =
+  keyof T['nb'] extends never
+    ? { can: T['can']; with: T['with'] }
+    : { can: T['can']; with: T['with']; nb: Partial<T['nb']> }
+
 export type InferCreateOptions<R extends Resource, C extends {} | undefined> =
   // If capability has no NB we want to prevent passing it into
-  // .create funciton so we make `nb` as optional `never` type so
+  // .create function so we make `nb` as optional `never` type so
   // it can not be satisfied
   keyof C extends never ? { with: R; nb?: never } : { with: R; nb: C }
 
@@ -213,22 +219,13 @@ export type InferDelegationOptions<
 }
 
 export type EmptyObject = { [key: string | number | symbol]: never }
-type Optionalize<T> = InferRequried<T> & InferOptional<T>
-
-type InferOptional<T> = {
-  [K in keyof T as T[K] | undefined extends T[K] ? K : never]?: T[K]
-}
-
-type InferRequried<T> = {
-  [K in keyof T as T[K] | undefined extends T[K] ? never : K]: T[K]
-}
 
 export interface CapabilityParser<M extends Match = Match> extends View<M> {
   /**
    * Defines capability that is either `this` or the the given `other`. This
    * allows you to compose multiple capabilities into one so that you could
    * validate any of one of them without having to maintain list of supported
-   * capabilities. It is especially useful when dealiving with derived
+   * capabilities. It is especially useful when dealing with derived
    * capability chains when you might derive capability from either one or the
    * other.
    */
@@ -282,7 +279,7 @@ export interface CapabilitiesParser<M extends Match[] = Match[]>
   extends View<Amplify<M>> {
   /**
    * Creates new capability group containing capabilities from this group and
-   * provedid `other` capability. This method complements `and` method on
+   * provided `other` capability. This method complements `and` method on
    * `Capability` to allow chaining e.g. `read.and(write).and(modify)`.
    */
   and<W extends Match>(other: MatchSelector<W>): CapabilitiesParser<[...M, W]>
@@ -312,39 +309,21 @@ export type InferMatch<Members extends unknown[]> = Members extends []
   ? [M, ...InferMatch<Rest>]
   : never
 
-export type ParsedCapability<
+export interface ParsedCapability<
   Can extends Ability = Ability,
   Resource extends URI = URI,
-  C extends object = {}
-> = keyof C extends never
-  ? { can: Can; with: Resource; nb?: C }
-  : { can: Can; with: Resource; nb: C }
-
-export type InferCaveats<C> = Optionalize<{
-  [K in keyof C]: C[K] extends Reader<infer T, unknown, infer _> ? T : never
-}>
-
-export interface Descriptor<
-  A extends Ability,
-  R extends URI,
-  C extends Caveats
+  C extends Caveats = {}
 > {
-  can: A
-  with: Reader<R, Resource, Failure>
-
-  nb?: C
-
-  derives?: Derives<
-    ToDeriveClaim<ParsedCapability<A, R, InferCaveats<C>>>,
-    ToDeriveClaim<ParsedCapability<A, R, InferCaveats<C>>>
-  >
+  can: Can
+  with: Resource
+  nb: C
 }
 
 export interface CapabilityMatch<
   A extends Ability,
   R extends URI,
   C extends Caveats
-> extends DirectMatch<ParsedCapability<A, R, InferCaveats<C>>> {}
+> extends DirectMatch<ParsedCapability<A, R, C>> {}
 
 export interface CanIssue {
   /**

packages/server/src/api.ts

@@ -1,5 +1,5 @@
 import * as API from '@ucanto/interface'
-import { InferCaveats, CanIssue, ParsedCapability } from '@ucanto/interface'
+import { CanIssue, ParsedCapability } from '@ucanto/interface'
 
 export * from '@ucanto/interface'
 
@@ -23,8 +23,8 @@ export interface ProviderContext<
   R extends API.URI = API.URI,
   C extends API.Caveats = API.Caveats
 > {
-  capability: API.ParsedCapability<A, R, API.InferCaveats<C>>
-  invocation: API.Invocation<API.Capability<A, R, API.InferCaveats<C>>>
+  capability: API.ParsedCapability<A, R, C>
+  invocation: API.Invocation<API.Capability<A, R, C>>
 
   context: API.InvocationContext
 }

packages/server/src/handler.js

@@ -6,15 +6,15 @@ import { access } from '@ucanto/validator'
  * @template {API.URI} R
  * @template {API.Caveats} C
  * @template {unknown} U
- * @param {API.CapabilityParser<API.Match<API.ParsedCapability<A, R, API.InferCaveats<C>>>>} capability
- * @param {(input:API.ProviderInput<API.ParsedCapability<A, R, API.InferCaveats<C>>>) => API.Await<U>} handler
- * @returns {API.ServiceMethod<API.Capability<A, R, API.InferCaveats<C>>, Exclude<U, {error:true}>, Exclude<U, Exclude<U, {error:true}>>>}
+ * @param {API.CapabilityParser<API.Match<API.ParsedCapability<A, R, C>>>} capability
+ * @param {(input:API.ProviderInput<API.ParsedCapability<A, R, C>>) => API.Await<U>} handler
+ * @returns {API.ServiceMethod<API.Capability<A, R, C>, Exclude<U, {error:true}>, Exclude<U, Exclude<U, {error:true}>>>}
  */
 
 export const provide =
   (capability, handler) =>
   /**
-   * @param {API.Invocation<API.Capability<A, R, API.InferCaveats<C>>>} invocation
+   * @param {API.Invocation<API.Capability<A, R, C>>} invocation
    * @param {API.InvocationContext} options
    */
   async (invocation, options) => {

packages/server/test/server.spec.js

@@ -5,13 +5,14 @@ import * as CBOR from '@ucanto/transport/cbor'
 import { alice, bob, mallory, service as w3 } from './fixtures.js'
 import * as Service from '../../client/test/service.js'
 import { test, assert } from './test.js'
+import { Schema } from '@ucanto/validator'
 
 const storeAdd = Server.capability({
   can: 'store/add',
   with: Server.URI.match({ protocol: 'did:' }),
-  nb: {
+  nb: Schema.struct({
     link: Server.Link.match().optional(),
-  },
+  }),
   derives: (claimed, delegated) => {
     if (claimed.with !== delegated.with) {
       return new Server.Failure(
@@ -34,9 +35,9 @@ const storeAdd = Server.capability({
 const storeRemove = Server.capability({
   can: 'store/remove',
   with: Server.URI.match({ protocol: 'did:' }),
-  nb: {
+  nb: Schema.struct({
     link: Server.Link.match().optional(),
-  },
+  }),
   derives: (claimed, delegated) => {
     if (claimed.with !== delegated.with) {
       return new Server.Failure(

packages/server/test/service/store.js

@@ -4,13 +4,14 @@ import { provide } from '../../src/handler.js'
 import * as API from './api.js'
 import * as Access from './access.js'
 import { service as issuer } from '../fixtures.js'
+import { Schema } from '@ucanto/validator/src/lib.js'
 
 const addCapability = Server.capability({
   can: 'store/add',
   with: Server.URI.match({ protocol: 'did:' }),
-  nb: {
+  nb: Schema.struct({
     link: Server.Link.match().optional(),
-  },
+  }),
   derives: (claimed, delegated) => {
     if (claimed.with !== delegated.with) {
       return new Server.Failure(
@@ -34,9 +35,9 @@ const addCapability = Server.capability({
 const removeCapability = Server.capability({
   can: 'store/remove',
   with: Server.URI.match({ protocol: 'did:' }),
-  nb: {
+  nb: Schema.struct({
     link: Server.Link.match().optional(),
-  },
+  }),
   derives: (claimed, delegated) => {
     if (claimed.with !== delegated.with) {
       return new Server.Failure(