Add basic block object interfaces

src/app/configs/app.config.ts

@@ -17,6 +17,7 @@ export default {
             refs: {
                 peers: 'chain/server/peers',
                 transaction: 'chain/pending/transactions',
+                block: 'chain/local/block',
             },
         },
     }

src/app/rtdb/BlockResource.ts

@@ -0,0 +1,57 @@
+import {FirebaseResource, FirebaseResourceItem} from "../FirebaseResource"
+import {Injectable} from "@extollo/di"
+import {RTDBRef} from "../units/FirebaseUnit"
+import {AsyncCollection} from "@extollo/util"
+
+export interface BlockEncounterTransaction {
+    combinedHash: string;
+    timestamp: number;
+    encodedGPSLocation: string;
+}
+
+export interface BlockInfectionTransaction {
+    clientID: string;
+    timestamp: number;
+}
+
+export type BlockTransaction = BlockInfectionTransaction | BlockEncounterTransaction
+
+export function isBlockEncounterTransaction(what: any): what is BlockEncounterTransaction {
+    return (
+        what
+        && typeof what.combinedHash === 'string'
+        && typeof what.timestamp === 'number'
+        && typeof what.encodedGPSLocation === 'string'
+    )
+}
+
+export function isBlockInfectionTransaction(what: any): what is BlockInfectionTransaction {
+    return (
+        what
+        && typeof what.clientID === 'string'
+        && typeof what.timestamp === 'number'
+    )
+}
+
+export function isBlockTransaction(what: any): what is BlockTransaction {
+    return isBlockEncounterTransaction(what) || isBlockInfectionTransaction(what)
+}
+
+export interface BlockResourceItem extends FirebaseResourceItem {
+    uuid: string;
+    combinedHash: string;
+    timestamp: number;
+    encodedGPSLocation: string;
+    transactions: BlockTransaction[];
+    lastBlockHash: string;
+    lastBlockUUID: string;
+}
+
+@Injectable()
+export class BlockResource extends FirebaseResource<BlockResourceItem> {
+    public static collect(): AsyncCollection<BlockResourceItem> {
+        return new AsyncCollection<BlockResourceItem>(new BlockResource())
+    }
+
+    protected refName: RTDBRef = 'block'
+}

src/app/units/Blockchain.ts

@@ -0,0 +1,110 @@
+import {Singleton, Inject} from "@extollo/di"
+import {Unit, Logging} from "@extollo/lib"
+import {FirebaseUnit} from "./FirebaseUnit"
+import {BlockResource, BlockResourceItem, BlockTransaction} from "../rtdb/BlockResource"
+import {TransactionResourceItem} from "../rtdb/TransactionResource"
+import * as crypto from "crypto"
+
+export class Block implements BlockResourceItem {
+    seqID: number;
+    uuid: string;
+    combinedHash: string;
+    timestamp: number;
+    encodedGPSLocation: string;
+    transactions: BlockTransaction[];
+    lastBlockHash: string;
+    lastBlockUUID: string;
+
+    constructor(rec: BlockResourceItem) {
+        this.seqID = rec.seqID
+        this.uuid = rec.uuid
+        this.combinedHash = rec.combinedHash
+        this.timestamp = rec.timestamp
+        this.encodedGPSLocation = rec.encodedGPSLocation
+        this.transactions = rec.transactions
+        this.lastBlockHash = rec.lastBlockHash
+        this.lastBlockUUID = rec.lastBlockUUID
+    }
+
+    hash() {
+        return crypto.createHash('sha256')
+            .update(this.toString(), 'utf-8')
+            .digest('hex')
+    }
+
+    toString() {
+        return [
+            this.uuid,
+            this.combinedHash,
+            this.timestamp.toString(),
+            this.encodedGPSLocation,
+            JSON.stringify(this.transactions),
+            this.lastBlockHash,
+            this.lastBlockUUID,
+        ].join('%')
+    }
+}
+
+export interface Peer {
+    host: string,
+    name?: string,
+}
+
+/**
+ * Blockchain Unit
+ * ---------------------------------------
+ * Main service for interacting with the contact blockchain.
+ */
+@Singleton()
+export class Blockchain extends Unit {
+    @Inject()
+    protected readonly logging!: Logging
+
+    @Inject()
+    protected readonly firebase!: FirebaseUnit
+
+    public async hasPeer(host: string): Promise<boolean> {
+        const peers = await this.getPeers()
+        return peers.some(peer => peer.host.toLowerCase() === host.toLowerCase())
+    }
+
+    public async getPeers(): Promise<Peer[]> {
+        const data = await this.firebase.ref('peers').once('value')
+        return (data.val() as Peer[]) || []
+    }
+
+    public async registerPeer(peer: Peer) {
+        if ( !(await this.hasPeer(peer.host)) ) {
+            await this.firebase.ref('peers').push().set(peer)
+        }
+    }
+
+    public async validate(chain: Block[]) {
+
+    }
+
+    public async refresh() {
+
+    }
+
+    public async submitBlock(afterBlock: Block, proofToken: string) {
+
+    }
+
+    public async submitTransactions(group: [TransactionResourceItem, TransactionResourceItem]) {
+        // Not sure yet
+    }
+
+    public async getLastBlock(): Promise<Block | undefined> {
+        const rec: BlockResourceItem | undefined = await BlockResource.collect().last()
+        return rec ? new Block(rec) : undefined
+    }
+
+    public async up() {
+
+    }
+
+    public async down() {
+
+    }
+}

src/app/units/FirebaseUnit.ts

@@ -2,7 +2,7 @@ import {Singleton, Inject} from "@extollo/di"
 import {Unit, Logging, Config} from "@extollo/lib"
 import * as firebase from "firebase-admin"
 
-export type RTDBRef = 'peers' | 'transaction'
+export type RTDBRef = 'peers' | 'transaction' | 'block'
 
 /**
  * FirebaseUnit Unit