GetCursor - - Alibaba Cloud Documentation Center

Queries a cursor based on a point in time.

Operation description

Usage notes

Host consists of a project name and a Simple Log Service endpoint. You must specify a project in Host.
The following content describes the relationships among a cursor, project, Logstore, and shard:
- A project can have multiple Logstores.
- A Logstore can have multiple shards.
- You can use a cursor to obtain a log in a shard.

Debugging

OpenAPI Explorer automatically calculates the signature value. For your convenience, we recommend that you call this operation in OpenAPI Explorer.

Debug

Authorization information

The following table shows the authorization information corresponding to the API. The authorization information can be used in the Action policy element to grant a RAM user or RAM role the permissions to call this API operation. Description:

Operation: the value that you can use in the Action element to specify the operation on a resource.
Access level: the access level of each operation. The levels are read, write, and list.
Resource type: the type of the resource on which you can authorize the RAM user or the RAM role to perform the operation. Take note of the following items:
- The required resource types are displayed in bold characters.
- If the permissions cannot be granted at the resource level, All Resources is used in the Resource type column of the operation.
Condition Key: the condition key that is defined by the cloud service.
Associated operation: other operations that the RAM user or the RAM role must have permissions to perform to complete the operation. To complete the operation, the RAM user or the RAM role must have the permissions to perform the associated operations.

Operation	Access level	Resource type	Condition key	Associated operation
log:GetCursorOrData	Read	LogStore acs:log:{#regionId}:{#accountId}:project/{#ProjectName}/logstore/{#LogstoreName}	log:TLSVersion	none

Request syntax

GET /logstores/{logstore}/shards/{shardId}?type=cursor

Request parameters

Parameter	Type	Required	Description	Example
project	string	Yes	The name of the project.	ali-test-project
logstore	string	Yes	The name of the Logstore.	sls-test-logstore
shardId	integer	Yes	The shard ID.	1
from	string	Yes	The point in time that you want to use to query a cursor. Set the value to a UNIX timestamp or a string such as `begin` and `end`.	begin

You can use the from parameter to locate a log in a shard within the lifecycle of a Logstore. If the lifecycle of a Logstore is [begin_time, end_time) and the from parameter is set to from_time, the cursor that is returned varies based on the following conditions:

from_time ≤ begin_time or from_time = "begin": The cursor that corresponds to begin_time is returned.
from_time ≥ end_time or from_time = "end": The cursor that corresponds to the next log to be written based on the current time is returned. The cursor currently points to no data.
from_time > begin_time and from_time < end_time: The cursor that corresponds to the first packet received by the server later than or at from_time is returned.

Note The lifecycle of a Logstore is specified by the TTL field in the attributes of the Logstore. For example, the data of a Logstore is received at 2018-11-11 09:00:00, and the value of the TTL field of the Logstore is 5. The data in each shard of the Logstore can be consumed within the time range [2018-11-05 09:00:00, 2018-11-11 09:00:00). The time range is determined based on the time on the server side. For more information, see the Data Retention Period parameter in the Manage a Logstore topic.

Response parameters

Parameter	Type	Description	Example
headers	object
Server	string	The name of the server.	nginx
Content-Type	string	The format in which the response body is returned.	application/json
Content-Length	string	The length of the response body.	0
Connection	string	Indicates whether the connection is persistent. Valid values: close: The connection is non-persistent. A new TCP connection is established for each HTTP request. keep-alive: The connection is persistent. After a TCP connection is established, the connection remains open, and no more time or bandwidth is consumed to establish new connections.	close
Date	string	The time when the response was returned.	Sun, 27 May 2018 08:25:04 GMT
x-log-requestid	string	The request ID.	5B0A6B60BB6EE39764D458B5
	object	The value of the cursor.
cursor	string	The value of the cursor.	MTQ0NzI5OTYwNjg5NjYzMjM1Ng==

Examples

Sample success responses

JSONformat

{
  "cursor": "MTQ0NzI5OTYwNjg5NjYzMjM1Ng=="
}

Error codes

For a list of error codes, visit the Service error codes.