refactor(daemon): Add known-peers-store formula (merge #2179)

Closes #2166 

Replace the known peers store adapter with a dedicated `known-peers-store` formula type, instantiated the same way as other "special" formulas such as `least-authority`. The adapter used a `pet-store` formula under the hood. Giving it a different formula entirely is probably less likely to confuse us in the future.

packages/daemon/src/daemon.js

@@ -15,7 +15,7 @@ import { makeGuestMaker } from './guest.js';
 import { makeHostMaker } from './host.js';
 import { assertPetName } from './pet-name.js';
 import { makeContextMaker } from './context.js';
-import { parseId, formatId } from './formula-identifier.js';
+import { assertValidNumber, parseId, formatId } from './formula-identifier.js';
 import { makeSerialJobs } from './serial-jobs.js';
 import { makeWeakMultimap } from './weak-multimap.js';
 import { makeLoopbackNetwork } from './networks/loopback.js';
@@ -127,15 +127,18 @@ const makeDaemonCore = async (
   );
   console.log('Node', ownNodeIdentifier);
 
-  const peersFormulaNumber = deriveId(
+  const knownPeersFormulaNumber = deriveId(
     'peers',
     rootEntropy,
     cryptoPowers.makeSha512(),
   );
-  const ownPeersId = formatId({
-    number: peersFormulaNumber,
+  const knownPeersId = formatId({
+    number: knownPeersFormulaNumber,
     node: ownNodeIdentifier,
   });
+  await persistencePowers.writeFormula(knownPeersFormulaNumber, {
+    type: 'known-peers-store',
+  });
 
   // Prepare least authority formula
   const leastAuthorityFormulaNumber = deriveId(
@@ -620,10 +623,11 @@ const makeDaemonCore = async (
           );
         },
         addPeerInfo: async peerInfo => {
-          // eslint-disable-next-line no-use-before-define
-          const knownPeers = await provideKnownPeers(formula.peers);
+          const knownPeers = /** @type {import('./types.js').PetStore} */ (
+            // eslint-disable-next-line no-use-before-define
+            await provide(formula.peers)
+          );
           const { node: nodeIdentifier, addresses } = peerInfo;
-          // eslint-disable-next-line no-use-before-define
           if (knownPeers.has(nodeIdentifier)) {
             // We already have this peer.
             // TODO: merge connection info
@@ -687,9 +691,19 @@ const makeDaemonCore = async (
     } else if (formula.type === 'pet-store') {
       const external = petStorePowers.makeIdentifiedPetStore(
         formulaNumber,
+        'pet-store',
         assertPetName,
       );
       return { external, internal: undefined };
+    } else if (formula.type === 'known-peers-store') {
+      const external = petStorePowers.makeIdentifiedPetStore(
+        formulaNumber,
+        'known-peers-store',
+        // The known peers store is just a pet store that only accepts node identifiers
+        // (i.e. formula numbers) as "names".
+        assertValidNumber,
+      );
+      return { external, internal: undefined };
     } else if (formula.type === 'pet-inspector') {
       // Behold, unavoidable forward-reference:
       // eslint-disable-next-line no-use-before-define
@@ -823,9 +837,11 @@ const makeDaemonCore = async (
     if (nodeIdentifier === ownNodeIdentifier) {
       throw new Error(`Cannot get peer formula identifier for self`);
     }
-    // eslint-disable-next-line no-use-before-define
-    const knownPeers = await provideKnownPeers(ownPeersId);
-    const peerId = knownPeers.identify(nodeIdentifier);
+    const knownPeers = /** @type {import('./types.js').PetStore} */ (
+      // eslint-disable-next-line no-use-before-define
+      await provide(knownPeersId)
+    );
+    const peerId = knownPeers.identifyLocal(nodeIdentifier);
     if (peerId === undefined) {
       throw new Error(
         `No peer found for node identifier ${q(nodeIdentifier)}.`,
@@ -1372,12 +1388,6 @@ const makeDaemonCore = async (
         await randomHex512(),
       );
       const { id: networksDirectoryId } = await formulateNetworksDirectory();
-      const { id: newPeersId } = await formulateNumberedPetStore(
-        peersFormulaNumber,
-      );
-      if (newPeersId !== ownPeersId) {
-        assert.Fail`Peers PetStore formula identifier did not match expected value, expected ${ownPeersId}, got ${newPeersId}`;
-      }
 
       // Ensure the default host is formulated and persisted.
       const { id: defaultHostId } = await formulateNumberedHost(
@@ -1399,7 +1409,7 @@ const makeDaemonCore = async (
     const formula = {
       type: 'endo',
       networks: identifiers.networksDirectoryId,
-      peers: ownPeersId,
+      peers: knownPeersId,
       host: identifiers.defaultHostId,
       leastAuthority: leastAuthorityId,
     };
@@ -1481,33 +1491,6 @@ const makeDaemonCore = async (
     throw new Error('Cannot connect to peer: no supported addresses');
   };
 
-  /**
-   * The "known peers store" is like a pet store, but maps node identifiers to
-   * full peer ids.
-   *
-   * @type {import('./types.js').DaemonCore['provideKnownPeers']}
-   */
-  const provideKnownPeers = async peersFormulaId => {
-    // "Known peers" is just a pet store with an adapter over it.
-    const petStore = /** @type {import('./types.js').PetStore} */ (
-      await provide(peersFormulaId)
-    );
-
-    // Pet stores do not accept full ids as names.
-    /** @param {string} nodeIdentifier */
-    const getNameFor = nodeIdentifier => {
-      return `p${nodeIdentifier.slice(0, 126)}`;
-    };
-
-    return harden({
-      has: nodeIdentifier => petStore.has(getNameFor(nodeIdentifier)),
-      identify: nodeIdentifier =>
-        petStore.identifyLocal(getNameFor(nodeIdentifier)),
-      write: (nodeIdentifier, peerId) =>
-        petStore.write(getNameFor(nodeIdentifier), peerId),
-    });
-  };
-
   /**
    * This is used to provide a value for a formula identifier that is known to
    * originate from the specified peer.

packages/daemon/src/formula-identifier.js

@@ -11,6 +11,15 @@ const idPattern = /^(?<number>[0-9a-f]{128}):(?<node>[0-9a-f]{128})$/;
 export const isValidNumber = allegedNumber =>
   typeof allegedNumber === 'string' && numberPattern.test(allegedNumber);
 
+/**
+ * @param {string} allegedNumber - The formula number or node identifier to test.
+ */
+export const assertValidNumber = allegedNumber => {
+  if (!isValidNumber(allegedNumber)) {
+    throw assert.error(`Invalid number ${q(allegedNumber)}`);
+  }
+};
+
 /**
  * @param {string} id
  * @param {string} [petName]

packages/daemon/src/formula-type.js

@@ -10,6 +10,7 @@ const formulaTypes = new Set([
   'guest',
   'handle',
   'host',
+  'known-peers-store',
   'least-authority',
   'lookup',
   'loopback-network',

packages/daemon/src/pet-store.js

@@ -222,11 +222,13 @@ export const makePetStoreMaker = (filePowers, locator) => {
   };
 
   /**
-   * @param {string} formulaNumber
-   * @param {(name: string) => void} assertValidName
-   * @returns {Promise<import('./types.js').PetStore>}
+   * @type {import('./types.js').PetStorePowers['makeIdentifiedPetStore']}
    */
-  const makeIdentifiedPetStore = (formulaNumber, assertValidName) => {
+  const makeIdentifiedPetStore = (
+    formulaNumber,
+    formulaType,
+    assertValidName,
+  ) => {
     if (!isValidNumber(formulaNumber)) {
       throw new Error(
         `Invalid formula number for pet store ${q(formulaNumber)}`,
@@ -236,7 +238,7 @@ export const makePetStoreMaker = (filePowers, locator) => {
     const suffix = formulaNumber.slice(2);
     const petNameDirectoryPath = filePowers.joinPath(
       locator.statePath,
-      'pet-store',
+      formulaType,
       prefix,
       suffix,
     );

packages/daemon/src/types.d.ts

@@ -181,6 +181,10 @@ type HandleFormula = {
   target: string;
 };
 
+type KnownPeersStoreFormula = {
+  type: 'known-peers-store';
+};
+
 type PetStoreFormula = {
   type: 'pet-store';
 };
@@ -210,6 +214,7 @@ export type Formula =
   | WebBundleFormula
   | HandleFormula
   | PetInspectorFormula
+  | KnownPeersStoreFormula
   | PetStoreFormula
   | DirectoryFormula
   | PeerFormula;
@@ -488,12 +493,6 @@ export interface EndoPeer {
 export type EndoPeerControllerPartial = ControllerPartial<EndoPeer, undefined>;
 export type EndoPeerController = Controller<EndoPeer, undefined>;
 
-export interface EndoKnownPeers {
-  has: (nodeIdentifier: string) => boolean;
-  identify: (nodeIdentifier: string) => string | undefined;
-  write: (nodeIdentifier: string, peerId: string) => Promise<void>;
-}
-
 export interface EndoGateway {
   provide: (id: string) => Promise<unknown>;
 }
@@ -626,6 +625,7 @@ export type AssertValidNameFn = (name: string) => void;
 export type PetStorePowers = {
   makeIdentifiedPetStore: (
     id: string,
+    formulaType: 'pet-store' | 'known-peers-store',
     assertValidName: AssertValidNameFn,
   ) => Promise<PetStore>;
 };
@@ -858,8 +858,6 @@ export interface DaemonCore {
   provideController: (id: string) => Controller;
 
   provideControllerAndResolveHandle: (id: string) => Promise<Controller>;
-
-  provideKnownPeers: (peersFormulaId: string) => Promise<EndoKnownPeers>;
 }
 
 export interface DaemonCoreExternal {