Clean up transaction logging logic for encounters

src/Units.extollo.ts

@@ -1,10 +1,14 @@
 import {Config, Controllers, HTTPServer, Files, Middlewares, Routing, Unit} from '@extollo/lib'
-import {CommandLine} from "@extollo/cli";
-import {FirebaseUnit} from "./app/units/FirebaseUnit";
+import {CommandLine} from "@extollo/cli"
+import {FirebaseUnit} from "./app/units/FirebaseUnit"
+import {Blockchain} from "./app/units/Blockchain"
+import {Transaction} from "./app/units/rtdb/Transaction"
 
 export const Units = [
     Config,
     FirebaseUnit,
+    Blockchain,
+    Transaction,
     Files,
     CommandLine,
     Controllers,

src/app/FirebaseResource.ts

@@ -25,7 +25,7 @@ export class FirebaseResource<T extends FirebaseResourceItem> extends Iterable<T
         return new Promise<number>((res, rej) => {
             this.ref().orderByChild('seqID')
                 .on('value', snapshot => {
-                    res((this.resolveObject(snapshot.val()).reverse()?.[0]?.seqID || 0) + 1)
+                    res((this.resolveObject(snapshot.val()).reverse()?.[0]?.seqID ?? -1) + 1)
                 }, rej)
         })
     }
@@ -66,7 +66,22 @@ export class FirebaseResource<T extends FirebaseResourceItem> extends Iterable<T
      */
     async push(item: T): Promise<T> {
         item.seqID = await this.getNextID()
+        // @ts-ignore
+        delete item.firebaseID
         await this.ref().push(item)
+
+        // Look up the firebaseID
+        await new Promise<void>((res, rej) => {
+            this.ref().orderByChild('seqID')
+                .limitToLast(1)
+                .on('value', snapshot => {
+                    if ( snapshot.val() ) {
+                        item.firebaseID = Object.keys(snapshot.val())[0]
+                    }
+                    res()
+                })
+        })
+
         return item
     }
 

src/app/units/Blockchain.ts

@@ -156,6 +156,9 @@ export class Blockchain extends Unit {
     public async submitTransactions(group: [TransactionResourceItem, TransactionResourceItem]) {
         const lastBlock = await this.getLastBlock()
 
+        this.logging.verbose('Last block:')
+        this.logging.verbose(lastBlock)
+
         const block: BlockResourceItem = {
             timestamp: (new Date).getTime(),
             uuid: uuid_v4(),
@@ -178,6 +181,7 @@ export class Blockchain extends Unit {
     public async getGenesisBlock(): Promise<Block> {
         const message = openpgp.Message.fromText("0000")
         const privateKey = this.config.get("app.gpg.key.private")
+
         return new Block({
             timestamp: (new Date).getTime(),
             uuid: '0000',
@@ -186,8 +190,10 @@ export class Blockchain extends Unit {
             lastBlockUUID: '',
             proof: (await openpgp.sign({
                 message,
-                privateKeys: privateKey
-            })).toString(),
+                privateKeys: await openpgp.readKey({
+                    armoredKey: privateKey
+                }),
+            })),
             firebaseID: '',
             seqID: -1,
         })
@@ -202,7 +208,7 @@ export class Blockchain extends Unit {
 
         const genesis = (await this.getGenesisBlock()).toItem()
         await (<BlockResource>this.app().make(BlockResource)).push(genesis)
-        return this.getLastBlock()
+        return new Block(genesis)
     }
 
     /**
@@ -231,7 +237,9 @@ export class Blockchain extends Unit {
         // Sign the hash using the server's private key
         return (await openpgp.sign({
             message,
-            privateKeys: privateKey
+            privateKeys: await openpgp.readKey({
+                armoredKey: privateKey,
+            })
         })).toString()
     }
 

src/app/units/rtdb/Transaction.ts

@@ -12,49 +12,71 @@ import { Blockchain } from "../Blockchain"
  */
 @Singleton()
 export class Transaction extends Unit {
+    private processing: boolean = false
+
     @Inject()
     protected readonly firebase!: FirebaseUnit
 
     @Inject()
     protected readonly blockchain!: Blockchain
 
+    @Inject()
+    protected readonly logging!: Logging
+
+    claim() {
+        if ( !this.processing ) {
+            this.processing = true
+            return true
+        }
+
+        return false
+    }
+
+    release() {
+        this.processing = false
+    }
+
     public async compareTransactions(transaction1: TransactionResourceItem, transaction2: TransactionResourceItem) {
         // verify signature
         const result1 = await openpgp.verify({
             publicKeys: await openpgp.readKey({
                 armoredKey: transaction2.partnerPublicKey
             }),
-            message: openpgp.Message.fromText(transaction1.combinedHash),
-            signature: await openpgp.readSignature({
-                armoredSignature: transaction1.validationSignature // parse detached signature
-            })
+            message: await openpgp.readMessage({
+                armoredMessage: transaction1.validationSignature,
+            }),
         })
+
         const result2 = await openpgp.verify({
             publicKeys: await openpgp.readKey({
                 armoredKey: transaction1.partnerPublicKey
             }),
-            message: openpgp.Message.fromText(transaction2.combinedHash),
-            signature: await openpgp.readSignature({
-                armoredSignature: transaction2.validationSignature // parse detached signature
+            message: await openpgp.readMessage({
+                armoredMessage: transaction2.validationSignature,
+            }),
         })
-        })
-        return await (result1.signatures[0].verified) && await (result2.signatures[0].verified)
+
+        return (await result1.signatures[0].verified) && (await result2.signatures[0].verified)
     }
 
     public async up() {
-        this.firebase.ref("transaction").on("value", async () => {
-            // array of pairs of tranaction resource items
-            const groupedTransactions: [TransactionResourceItem, TransactionResourceItem][] = []
+        this.firebase.ref("transaction").on("child_added", async () => {
+            this.logging.debug('Received child_added event for transactions reference.')
+            if ( !this.claim() ) return
+
+            // array of pairs of transaction resource items
+            let groupedTransactions: [TransactionResourceItem, TransactionResourceItem][] = []
             // collection of transaction resource items
             let transactions = await TransactionResource.collect().collect()
+
             // compare each item
-            transactions.each(transaction1 => {
+            await transactions.promiseMap(async transaction1 => {
                 // for each item that is not itself
-                transactions.where("combinedHash", "!=", transaction1.combinedHash)
+                await transactions.where('combinedHash', '!=', transaction1.combinedHash)
                     // get a second item
-                    .each(transaction2 => {
+                    .promiseMap(async transaction2 => {
                         //if the item matches
-                        if (this.compareTransactions(transaction1, transaction2)) {
+                        if ( await this.compareTransactions(transaction1, transaction2) ) {
                             // and remove the two matching items
                             transactions = transactions.whereNotIn("combinedHash", [transaction1.combinedHash, transaction2.combinedHash])
                             // insert grouped items into groupedTransactions
@@ -62,14 +84,34 @@ export class Transaction extends Unit {
                         }
                     })
             })
+
+            const seenCombinedHashes: string[] = []
+            groupedTransactions = groupedTransactions.filter(group => {
+                const key = group.map(x => x.combinedHash).sort().join('-')
+                if ( !seenCombinedHashes.includes(key) ) {
+                    seenCombinedHashes.push(key)
+                    return true
+                }
+
+                return false
+            })
+
             for (const group of groupedTransactions) {
-                await this.blockchain.submitTransactions(group)
+                const block = await this.blockchain.submitTransactions(group)
+
+                this.logging.verbose('Created block:')
+                this.logging.verbose(block)
+
                 await this.firebase.ref("transaction").child(group[0].firebaseID).remove()
                 await this.firebase.ref("transaction").child(group[1].firebaseID).remove()
             }
+
+            this.release()
         })
     }
 
     public async down() {
+        // Release all subscriptions before shutdown
+        this.firebase.ref("transaction").off()
     }
 }