Added cli command oracle-file for submitting prices by updating a local file (#3)

README.md

@@ -54,6 +54,23 @@ not use this key for production!
 NOTE 2: You might get error messages if somebody else is also running the
 oracle.
 
+### Manual price feed
+Alternatively, you can submit prices to the oracle manually by instructing the oracle to watch for changes to a local file.
+This can be useful for testing specific behaviour (such as triggering liquidations).
+
+Run the oracle: 
+```
+yarn solink oracle-file {pair} {filepath}
+```
+
+{pair} must be one of the aggregator pairs in deploy.sandbox.json
+
+Then you can update prices by running
+```
+echo {price} > {filepath}
+```
+
+
 # Observe The Aggregators
 
 With the oracle running, you can subscribe to price changes. In another

src/cli.ts

@@ -10,6 +10,8 @@ import { PriceFeeder } from "./PriceFeeder"
 import { sleep, walletFromEnv } from "./utils"
 import { PublicKey, Wallet } from "solray"
 import { log } from "./log"
+import { Submitter } from "./Submitter"
+import { file } from "./feeds"
 
 const cli = new Command()
 
@@ -83,4 +85,51 @@ cli.command("observe").action(async (name?: string) => {
   }
 })
 
+
+cli.command("oracle-file <pair> <path>").action(async (pair, path) => {
+
+  console.log(pair);
+  console.log(path);
+
+  let deployInfo = loadJSONFile<AggregatorDeployFile>(process.env.DEPLOY_FILE!)
+  
+  // validate pair arg here
+  if (!(pair in deployInfo.aggregators)) {
+    throw 'Invalid pair ' + pair;
+  }
+
+  let slot = await conn.getSlot()
+  conn.onSlotChange((slotInfo) => {
+    slot = slotInfo.slot
+  })
+  
+  const wallet = await walletFromEnv("ORACLE_MNEMONIC", conn)
+  // await maybeRequestAirdrop(wallet.pubkey)
+  
+  let aggregatorInfo = deployInfo.aggregators[pair];
+  
+  const oracleInfo = Object.values(aggregatorInfo.oracles).find(
+    (oracleInfo) => {
+      return oracleInfo.owner.equals(wallet.pubkey)
+    }
+  )
+  
+  let minValueChangeForNewRound = 0
+  
+  const submitter = new Submitter(
+    deployInfo.programID,
+    aggregatorInfo.pubkey,
+    oracleInfo!.pubkey,
+    wallet,
+    file(pair, path),
+    {
+      minValueChangeForNewRound,
+    },
+    () => slot
+  )
+
+  submitter.start();
+
+})
+
 cli.parse(process.argv)

src/feeds.ts

@@ -5,7 +5,7 @@ import { eventsIter, median, notify } from "./utils"
 
 import { log } from "./log"
 import winston from "winston"
-
+import fs from "fs";
 
 const SECONDS = 1000
 export const UPDATE = "UPDATE"
@@ -444,3 +444,32 @@ export function coinbase(pair: string): IPriceFeed {
 
   return eventsIter(emitter, UPDATE)
 }
+
+export function file(pair: string, filepath: string): IPriceFeed {
+  const emitter = new EventEmitter()
+  
+  try {
+    fs.accessSync(filepath);
+  } catch {
+    fs.writeFileSync(filepath, '');
+    console.log('feed file created at ' + filepath)
+  }
+
+  console.log('started file feed for ' + pair)
+
+  fs.watch(filepath, (event) => {
+    if (event === 'change') {
+      const data = fs.readFileSync(filepath, 'utf8')
+      const price: IPrice = {
+        source: "file",
+        pair,
+        decimals: 2,
+        value: parseFloat(data)
+      }
+      console.log('price update: ', price)
+      emitter.emit(UPDATE, price)
+    }
+  });
+
+  return eventsIter(emitter, UPDATE)
+}