Error while running chat-node.js

[dharwishr]

Possibly Unhandled Rejection at: Promise Promise {
{ Error: ENOENT: no such file or directory, open 'priv_validator.json'
at Object.fs.openSync (fs.js:652:18)
at Object.fs.readFileSync (fs.js:553:33)
at Lotion (/home/node/blockchat/node_modules/lotion/index.js:63:19)
at main (/home/node/blockchat/chat-node.js:69:15)
at Object. (/home/node/blockchat/chat-node.js:132:1)
at Module._compile (module.js:569:30)
at Object.Module._extensions..js (module.js:580:10)
at Module.load (module.js:503:32)
at tryModuleLoad (module.js:466:12)
at Function.Module._load (module.js:458:3)
errno: -2,
code: 'ENOENT',
syscall: 'open',
path: 'priv_validator.json' } } reason: { Error: ENOENT: no such file or directory, open 'priv_validator.json'
at Object.fs.openSync (fs.js:652:18)
at Object.fs.readFileSync (fs.js:553:33)
at Lotion (/home/node/blockchat/node_modules/lotion/index.js:63:19)
at main (/home/node/blockchat/chat-node.js:69:15)
at Object. (/home/node/blockchat/chat-node.js:132:1)
at Module._compile (module.js:569:30)
at Object.Module._extensions..js (module.js:580:10)
at Module.load (module.js:503:32)
at tryModuleLoad (module.js:466:12)
at Function.Module._load (module.js:458:3)
errno: -2,
code: 'ENOENT',
syscall: 'open',
path: 'priv_validator.json' }
Trace
at process. (/home/node/blockchat/chat-node.js:129:13)
at emitTwo (events.js:125:13)
at process.emit (events.js:213:7)
at emitPendingUnhandledRejections (internal/process/promises.js:85:22)
at runMicrotasksCallback (internal/process/next_tick.js:124:9)
at _combinedTickCallback (internal/process/next_tick.js:131:7)
at process._tickCallback (internal/process/next_tick.js:180:9)
at Function.Module.runMain (module.js:607:11)
at startup (bootstrap_node.js:158:16)
at bootstrap_node.js:575:3