设置了30秒超时，但是还是经常有超时的，下面是常见的失败返回，一天都有428条失败的

'err':'{"errno":5,"errMsg":"request:fail timeout"}'

"err":{"errno":600001,"errMsg":"request:fail errcode:-118 cronet_error_code:-118 error_msg:net::ERR_CONNECTION_TIMED_OUT"}

"err":{"errno":600003,"errMsg":"request:fail interrupted"}

"err":{"errMsg":"request:fail -105:net::ERR_NAME_NOT_RESOLVED","errCode":600001}

"err":{"errno":600001,"errMsg":"request:fail -103:net::ERR_CONNECTION_ABORTED"}

"err":{"errno":600001,"errMsg":"request:fail -101:net::ERR_CONNECTION_RESET"}

"err":{"errno":600001,"errMsg":"request:fail -109:net::ERR_ADDRESS_UNREACHABLE"}

"err":{"errno":600001,"errMsg":"request:fail -200:net::ERR_CERT_COMMON_NAME_INVALID"}