npm install
error Error: CERT_UNTRUSTED
225 error at SecurePair.<anonymous> (tls.js:1370:32)
225 error at SecurePair.EventEmitter.emit (events.js:92:17)
225 error at SecurePair.maybeInitFinished (tls.js:982:10)
225 error at CleartextStream.read [as _read] (tls.js:469:13)
225 error at CleartextStream.Readable.read (_stream_readable.js:320:10)
225 error at EncryptedStream.write [as _write] (tls.js:366:25)
225 error at doWrite (_stream_writable.js:223:10)
225 error at writeOrBuffer (_stream_writable.js:213:5)
225 error at EncryptedStream.Writable.write (_stream_writable.js:180:11)
225 error at write (_stream_readable.js:583:24)
225 error at flow (_stream_readable.js:592:7)解决问题方式：ssl 验证问题，使用下面命令取消ssl验证即可解决：
npm config set strict-ssl false