Contract deletion handling

backend/database.js

@@ -42,12 +42,11 @@ if (!fs.existsSync(dataFolder)) {
 // Streams stored contract log entries since the given entry hash (inclusive!).
 export default ((sbp('sbp/selectors/register', {
   'backend/db/streamEntriesAfter': async function (contractID: string, height: string, requestedLimit: ?number): Promise<*> {
-    const resource = await sbp('chelonia/db/get', contractID)
-    if (resource === '') {
-      throw Boom.resourceGone(`contractID ${contractID} has been deleted!`)
-    }
     const limit = Math.min(requestedLimit ?? Number.POSITIVE_INFINITY, process.env.MAX_EVENTS_BATCH_SIZE ?? 500)
     const latestHEADinfo = await sbp('chelonia/db/latestHEADinfo', contractID)
+    if (latestHEADinfo === '') {
+      throw Boom.resourceGone(`contractID ${contractID} has been deleted!`)
+    }
     if (!latestHEADinfo) {
       throw Boom.notFound(`contractID ${contractID} doesn't exist!`)
     }

backend/index.js

@@ -50,7 +50,11 @@ console.error = logger.error.bind(logger)
 
 console.info('NODE_ENV =', process.env.NODE_ENV)
 
-const dontLog = { 'backend/server/broadcastEntry': true, 'backend/server/broadcastKV': true }
+const dontLog = {
+  'backend/server/broadcastEntry': true,
+  'backend/server/broadcastDeletion': true,
+  'backend/server/broadcastKV': true
+}
 
 function logSBP (domain, selector, data: Array<*>) {
   if (!dontLog[selector]) {

backend/routes.js

@@ -275,6 +275,9 @@ route.GET('/latestHEADinfo/{contractID}', {
   try {
     if (contractID.startsWith('_private')) return Boom.notFound()
     const HEADinfo = await sbp('chelonia/db/latestHEADinfo', contractID)
+    if (HEADinfo === '') {
+      return Boom.resourceGone()
+    }
     if (!HEADinfo) {
       console.warn(`[backend] latestHEADinfo not found for ${contractID}`)
       return Boom.notFound()

backend/server.js

@@ -153,6 +153,13 @@ sbp('sbp/selectors/register', {
     console.debug(chalk.blue.bold(`[pubsub] Broadcasting ${deserializedHEAD.description()}`))
     await pubsub.broadcast(pubsubMessage, { to: subscribers })
   },
+  'backend/server/broadcastDeletion': async function (contractID: string) {
+    const pubsub = sbp('okTurtles.data/get', PUBSUB_INSTANCE)
+    const pubsubMessage = createMessage(NOTIFICATION_TYPE.DELETION, contractID)
+    const subscribers = pubsub.enumerateSubscribers(contractID)
+    console.debug(chalk.blue.bold(`[pubsub] Broadcasting deletion of ${contractID}`))
+    await pubsub.broadcast(pubsubMessage, { to: subscribers })
+  },
   'backend/server/handleEntry': async function (deserializedHEAD: Object, entry: string) {
     const contractID = deserializedHEAD.contractID
     if (deserializedHEAD.head.op === GIMessage.OP_CONTRACT) {
@@ -306,6 +313,9 @@ sbp('sbp/selectors/register', {
       await sbp('chelonia/db/delete', `_private_cheloniaState_${cid}`)
       await removeFromIndexFactory('_private_cheloniaState_index')(cid)
       await removeFromIndexFactory('_private_billable_entities')(cid)
+      sbp('backend/server/broadcastDeletion', cid).catch(e => {
+        console.error(e, 'Error broadcasting contract deletion', cid)
+      })
     }).finally(() => {
       contractsPendingDeletion.delete(cid)
     })

frontend/controller/utils/misc.js

@@ -1,8 +1,10 @@
 'use strict'
 
+import { ChelErrorUnexpectedHttpResponseCode } from '~/shared/domains/chelonia/errors.js'
+
 export function handleFetchResult (type: string): ((r: any) => any) {
   return function (r: Object) {
-    if (!r.ok) throw new Error(`${r.status}: ${r.statusText}`)
+    if (!r.ok) throw new ChelErrorUnexpectedHttpResponseCode(`${r.status}: ${r.statusText}`)
     return r[type]()
   }
 }

frontend/setupChelonia.js

@@ -139,6 +139,12 @@ const setupChelonia = async (): Promise<*> => {
       }
     },
     hooks: {
+      syncContractError: (e, contractID) => {
+        // TODO
+        if (e?.name === 'ChelErrorUnexpectedHttpResponseCode' && e.message.startsWith('410:')) {
+          console.error('@@@@[syncContractError] Contract ID ' + contractID + ' has been deleted')
+        }
+      },
       handleEventError: (e: Error, message: GIMessage) => {
         if (e.name === 'ChelErrorUnrecoverable') {
           sbp('okTurtles.events/emit', SERIOUS_ERROR, e)
@@ -254,6 +260,10 @@ const setupChelonia = async (): Promise<*> => {
         if (!data) return
 
         sbp('okTurtles.events/emit', KV_EVENT, { contractID, key, data })
+      },
+      [NOTIFICATION_TYPE.DELETION] (contractID) {
+        // TODO
+        console.error('@@@@[NOTIFICATION] Contract ID ' + contractID + ' has been deleted')
       }
     },
     handlers: {

shared/domains/chelonia/chelonia.js

@@ -626,6 +626,8 @@ export default (sbp('sbp/selectors/register', {
                     console.error(`[chelonia] Error processing kv event for ${msg.channelID} and key ${msg.key}`, msg, e)
                   })
                 }]
+              case NOTIFICATION_TYPE.DELETION:
+                return [k, (msg) => v(msg.data)]
               default:
                 return [k, v]
             }

shared/domains/chelonia/db.js

@@ -102,7 +102,7 @@ export default (sbp('sbp/selectors/register', {
     return sbp('chelonia/db/get', getLogHead(contractID)).then((r) => r && JSON.parse(r))
   },
   'chelonia/db/deleteLatestHEADinfo': (contractID: string): Promise<void> => {
-    return sbp('chelonia/db/delete', getLogHead(contractID))
+    return sbp('chelonia/db/set', getLogHead(contractID), '')
   },
   'chelonia/db/getEntry': async function (hash: string): Promise<GIMessage> {
     try {

shared/domains/chelonia/errors.js

@@ -34,3 +34,4 @@ export const ChelErrorSignatureError: typeof Error = ChelErrorGenerator('ChelErr
 export const ChelErrorSignatureKeyUnauthorized: typeof Error = ChelErrorGenerator('ChelErrorSignatureKeyUnauthorized', ChelErrorSignatureError)
 export const ChelErrorSignatureKeyNotFound: typeof Error = ChelErrorGenerator('ChelErrorSignatureKeyNotFound', ChelErrorSignatureError)
 export const ChelErrorFetchServerTimeFailed: typeof Error = ChelErrorGenerator('ChelErrorFetchServerTimeFailed')
+export const ChelErrorUnexpectedHttpResponseCode: typeof Error = ChelErrorGenerator('ChelErrorUnexpectedHttpResponseCode')

shared/pubsub.js

@@ -96,6 +96,7 @@ export type UnsubMessage = {
 
 export const NOTIFICATION_TYPE = Object.freeze({
   ENTRY: 'entry',
+  DELETION: 'deletion',
   KV: 'kv',
   PING: 'ping',
   PONG: 'pong',