Restart mechanics in GunSmith for once()s

src/routes.js

@@ -2274,6 +2274,7 @@ module.exports = async (
      * @prop {string=} publicKey
      * @prop {string=} publicKeyForDecryption
      * @prop {string=} epubForDecryption
+     * @prop {boolean=} mustBePopulated
      */
     /**
      * @param {HandleGunFetchParams} args0
@@ -2285,7 +2286,8 @@ module.exports = async (
       path,
       publicKey,
       publicKeyForDecryption,
-      epubForDecryption
+      epubForDecryption,
+      mustBePopulated
     }) => {
       const keys = path.split('>')
       const { gun, user } = require('../services/gunDB/Mediator')
@@ -2315,7 +2317,7 @@ module.exports = async (
           }
         }
 
-        if (type === 'once') node.once(listener)
+        if (type === 'once') node.once(listener, { mustBePopulated })
         if (type === 'load') node.load(listener)
       })
     }
@@ -2340,7 +2342,8 @@ module.exports = async (
           startFromUserGraph: false,
           type: 'once',
           publicKeyForDecryption,
-          epubForDecryption
+          epubForDecryption,
+          mustBePopulated: !!req.header('must-be-populated')
         })
         res.status(200).json({
           data
@@ -2388,7 +2391,8 @@ module.exports = async (
           startFromUserGraph: true,
           type: 'once',
           publicKeyForDecryption,
-          epubForDecryption
+          epubForDecryption,
+          mustBePopulated: !!req.header('must-be-populated')
         })
         res.status(200).json({
           data

utils/GunSmith/GunSmith.js

@@ -13,7 +13,7 @@ const { fork } = require('child_process')
 
 const logger = require('../../config/log')
 
-const { mergePuts } = require('./misc')
+const { mergePuts, isPopulated } = require('./misc')
 
 const gunUUID = () => {
   const RG = /** @type {any} */ (RealGun)
@@ -366,14 +366,29 @@ function createReplica(path, afterMap = false) {
         mapListeners.delete(l)
       }
     },
-    on(cb) {
+    on(cb, { mustBePopulated } = {}) {
       listenersForThisRef.push(cb)
+
+      let canaryPeep = false
+      const canary = () => {
+        canaryPeep = true
+      }
+      listenersForThisRef.push(canary)
+      const checkCanary = () =>
+        setTimeout(() => {
+          if (!canaryPeep && mustBePopulated) {
+            forge()
+            checkCanary()
+          }
+        }, 5000)
+
       if (afterMap) {
         // eslint-disable-next-line no-multi-assign
         const listeners =
           pathToMapListeners[path] || (pathToMapListeners[path] = new Set())
 
         listeners.add(cb)
+        listeners.add(canary)
 
         /** @type {Smith.SmithMsgMapOn} */
         const msg = {
@@ -387,6 +402,7 @@ function createReplica(path, afterMap = false) {
           pathToListeners[path] || (pathToListeners[path] = new Set())
 
         listeners.add(cb)
+        listeners.add(canary)
 
         /** @type {Smith.SmithMsgOn} */
         const msg = {
@@ -398,7 +414,8 @@ function createReplica(path, afterMap = false) {
 
       return this
     },
-    once(cb, opts = { wait: 500 }) {
+    once(cb, _opts) {
+      const opts = { ...{ mustBePopulated: false, wait: 500 }, ..._opts }
       // We could use this.on() but then we couldn't call .off()
       const tmp = createReplica(path, afterMap)
       if (afterMap) {
@@ -412,15 +429,21 @@ function createReplica(path, afterMap = false) {
       })
 
       setTimeout(() => {
+        tmp.off()
         if (cb) {
+          if (opts.mustBePopulated && !isPopulated(lastVal)) {
+            forge()
+            this.once(cb, { ...opts, wait: 5000, mustBePopulated: false })
+          } else {
             cb(lastVal, path.split('>')[path.split('>').length - 1])
           }
-        tmp.off()
+        }
       }, opts.wait)
 
       return this
     },
     put(data, cb) {
+      logger.info('put()')
       const id = uuid()
 
       const pendingPutsForPath = pendingPuts[path] || (pendingPuts[path] = [])
@@ -502,11 +525,11 @@ function createReplica(path, afterMap = false) {
         }
       }
     },
-    then() {
+    then(opts) {
       return new Promise(res => {
         this.once(data => {
           res(data)
-        })
+        }, opts)
       })
     }
   }

utils/GunSmith/GunT.ts

@@ -58,6 +58,14 @@ namespace GunT {
 
   export type LoadListener = (data: LoadListenerData, key: string) => void
 
+  export interface GunSmithFetchOpts {
+    /**
+     * GunSmith exclusive. If set to true, gun will be restarted to force
+     * replication of this data.
+     */
+    mustBePopulated?: boolean
+  }
+
   export interface GUNNode {
     _: Soul
     /**
@@ -81,13 +89,26 @@ namespace GunT {
     load(this: GUNNode, cb?: LoadListener): GUNNode
     map(): GUNNode
     off(): void
-    on(this: GUNNode, cb: Listener): void
-    once(this: GUNNode, cb?: Listener, opts?: { wait: number }): GUNNode
+    on(
+      this: GUNNode,
+      cb: Listener,
+      opts?: {
+        change?: boolean
+      } & GunSmithFetchOpts
+    ): void
+    once(
+      this: GUNNode,
+      cb?: Listener,
+      opts?: { wait?: number } & GunSmithFetchOpts
+    ): GUNNode
     user(): UserGUNNode
     user(pub: string): GUNNode
     put(data: ValidDataValue, cb?: Callback): GUNNode
     set(data: ValidDataValue, cb?: Callback): GUNNode
-    then(): Promise<ListenerData>
+    /**
+     * @param options Gunsmith only.
+     */
+    then(opts?: GunSmithFetchOpts): Promise<ListenerData>
   }
 
   export interface CreateAck {