Queries the distribution of logs that meet the specified search conditions in a Logstore.
Operation description
Usage notes
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Host consists of a project name and a Simple Log Service endpoint. You must specify a project in Host.
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The time range is evenly divided into subintervals in the responses. If the time range that is specified in the request remains unchanged, the subintervals in the responses also remain unchanged.
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If the number of logs in a Logstore significantly changes, Simple Log Service cannot predict the number of times that you must call this operation to obtain the complete result. In this case, you must check the value of the progress parameter in the response of each request and determine whether to call this operation one more time to obtain the complete result. Each time you call this operation, the same number of charge units (CUs) are consumed.
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After a log is written to a Logstore, you can call the GetHistograms or GetLogs operation to query the log after a short latency. The latency of a query varies based on the type of the log. Simple Log Service classifies logs into the following types based on the log time:
- Real-time data: The difference between the time record in a log and the current time on Simple Log Service is within the interval (-180 seconds,900 seconds]. For example, if a log was generated at 12:03:00, September 25, 2014 (UTC) and Simple Log Service received the log at 12:05:00, September 25, 2014 (UTC), Simple Log Service processes the log as real-time data. After real-time data is written to a Logstore, the data can be queried with a maximum latency of 3 seconds.
- Historical data: The difference between the time record in a log and the current time on Simple Log Service is within the interval [-604,800 seconds,-180 seconds). For example, if a log was generated at 12:00:00, September 25, 2014 (UTC) and Simple Log Service received the log at 12:05:00, September 25, 2014 (UTC), Simple Log Service processes the log as historical data. This type of log is usually generated in data backfill scenarios.
After real-time data is written to a Logstore, the data can be queried with a maximum latency of 3 seconds. For 99.9% of queries, the latency is no more than 1 second.
- Simple Log Service provides examples on how to call the GetHistograms operation by using Simple Log Service SDK for Java. For more information, see Use GetHistograms to query the distribution of logs.
Debugging
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 Resourcesis 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:GetLogStoreHistogram | Read |
|
| none |
Request syntax
GET /logstores/{logstore}/index?type=histogram
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. | test-logstore |
| from | long | Yes | The start time of the subinterval. The value is a UNIX timestamp representing the number of seconds that have elapsed since the epoch time January 1, 1970, 00:00:00 UTC. | 1409529600 |
| to | long | Yes | The end time of the subinterval. The value is a UNIX timestamp representing the number of seconds that have elapsed since the epoch time January 1, 1970, 00:00:00 UTC. | 1409569200 |
| topic | string | No | The topic of the logs. | topic |
| query | string | No | The search statement. Only search statements are supported. Analytic statements are not supported. For more information about the syntax of search statements, see Log search overview. | with_pack_meta |
Response parameters
Examples
Sample success responses
JSONformat
[
{
"from": 1409529600,
"to": 1409569200,
"count": 2,
"progress": "Complete"
}
]Error codes
For a list of error codes, visit the Service error codes.