Reading records

If you do not have the Yandex Cloud command line interface yet, install and initialize it.

The folder specified in the CLI profile is used by default. You can specify a different folder using the --folder-name or --folder-id parameter.

When viewing the log, you can set a specific interval using the --since and --until flags. If no time interval is specified, information for the previous hour is displayed.

The following flags are used:

• --since: Time N and later (you can skip the --since flag and specify the time directly).
• --until: Time N and earlier.

If you only specify one flag, information is displayed for the hour before or after Time X depending on the flag.

Allowed time formats:

• HH:MM:SS, e.g., 15:04:05.
• RFC-3339. For example: 2006-01-02T15:04:05Z, 2h, 3h30m ago.

To access a log group, use its name or unique ID. To find them, get a list of log groups in the folder. If you do not specify the name or ID, the output will contain records from the default log group in the current folder. You can skip the --group-name and --group-id flags and specify the group name or ID directly.

You can limit the number of output records using the --limit flag. Acceptable values are from 1 to 1000.

To view the records in JSON format, run the command:

yc logging read --group-name=default --format=json

Result:

[
  {
    "uid": "488ece3c-75b8-4d35-95ac-2b49********",
    "resource": {},
    "timestamp": "2023-06-22T02:10:40Z",
    "ingested_at": "2023-06-22T08:49:15.716Z",
    "saved_at": "2023-06-22T08:49:16.176097Z",
    "level": "INFO",
    "message": "My message",
    "json_payload": {
      "request_id": "1234"
    }
  }
]

To read records as they appear, use the --follow flag:

yc logging read --group-name=default --follow

This command will display records from the most recent hour and will continue to return new records until you terminate it by pressing Ctrl + C. The --follow flag is incompatible with --since and --until.

To view log group records, use the LogReadingService/Read gRPC API call.

You can read records in Cloud Logging using the Yandex Cloud SDK implemented for different languages. Below are examples of using the Python SDK.

Locally

import os
import yandexcloud
import pprint
from yandex.cloud.logging.v1.log_reading_service_pb2 import ReadRequest
from yandex.cloud.logging.v1.log_reading_service_pb2 import Criteria
from yandex.cloud.logging.v1.log_reading_service_pb2_grpc import LogReadingServiceStub

def handler():
  cloud_logging_service = yandexcloud.SDK(iam_token=os.environ['iam']).client(LogReadingServiceStub)
  logs = {}
  criteria = Criteria(log_group_id='<log_group_ID>', resource_ids=['<resource_ID>'])
  read_request = ReadRequest(criteria=criteria)

  logs = cloud_logging_service.Read(read_request)
  return logs

pprint.pprint(handler())

Where:

• log_group_id: ID of the log group.
• resource_ids: ID of the resource, e.g., a Managed Service for Kubernetes cluster.

Yandex Cloud Functions

import yandexcloud
from yandex.cloud.logging.v1.log_reading_service_pb2 import ReadRequest
from yandex.cloud.logging.v1.log_reading_service_pb2 import Criteria
from yandex.cloud.logging.v1.log_reading_service_pb2_grpc import LogReadingServiceStub

def handler(event, context):
    cloud_logging_service = yandexcloud.SDK().client(LogReadingServiceStub)
    logs = {}
    criteria = Criteria(log_group_id='<log_group_ID>', resource_ids=['<resource_ID>'])
    read_request = ReadRequest(criteria=criteria)

    logs = cloud_logging_service.Read(read_request)
    return logs

Where:

• log_group_id: ID of the log group.
• resource_ids: ID of the resource, e.g., a Managed Service for Kubernetes cluster.

Function parameters:

• Runtime environment: python38
• Entry point: index.handler
• Timeout, sec: 3
• Memory: 128 MB