Simple Log Service:Perform paged queries

How pagination works

Paginate query results

When a paged query is performed, the value of the offset parameter increases until all logs are read. When the value reaches a specific number, 0 is returned, and the progress is complete. In this case, all the required data is read.

• Sample code for pagination

  offset = 0                           # Read logs from line 0. 
  line = 100                          # Read 100 lines at a time. 
  query = "status:200"                 # Query all logs in which the value of the status field is 200. 
  while True:
       response = get_logstore_logs(query, offset, line) # Call the operation to read logs. 
       process (response)                                 # Call custom logic to process the returned result. 
       if response.get_count() == 0 && response.is_complete()   
           The read process is complete, and the current loop ends.
       else
          offset += 100                          # The value of the offset parameter increases to 100. The next 100 lines are read.

• Sample code in Python

  For more information, see Overview of Simple Log Service SDK for Python.

  # The Simple Log Service endpoint. 
  endpoint = '' 
  # Configure environment variables. In this example, the AccessKey ID and AccessKey secret are obtained from environment variables. 
  accessKeyId = os.environ.get('ALIBABA_CLOUD_ACCESS_KEY_ID', '')
  accessKey = os.environ.get('ALIBABA_CLOUD_ACCESS_KEY_SECRET', '')
  # The name of the project. 
  project = ''     
  # The name of the Logstore. 
  logstore = ''  
  client = LogClient(endpoint, accessKeyId, accessKey)
  topic = ""
  From = int(time.time()) - 600
  To = int(time.time())
  log_line = 100
  offset = 0
  while True:
      res4 = None
      for retry_time in range(0, 3): 
          req4 = GetLogsRequest(project, logstore, From, To, topic=topic, line=log_line, offset=offset)
          res4 = client.get_logs(req4)
          if res4 is not None and res4.is_completed():
              break
          time.sleep(1)
       offset += 100 
       if res4.is_completed() and res4.get_count() == 0:
           break;
       if res4 is not None:
           # Display the execution result. 
          res4.log_print() 

• Sample code in Java

  For more information, see Overview of Simple Log Service SDK for Java.

  int log_offset = 0;
  int log_line = 100;   // The number of lines that are read at a time. A maximum of 100 lines can be returned. If you want to read more than 100 lines, use the offset parameter. The offset and line parameters take effect only for a search statement that uses keywords. If you use an analytic statement, these parameters are invalid. If you want an analytic statement to return more than 100 lines, use the LIMIT clause. 
  while (true) {
      GetLogsResponse res4 = null;
      // For each offset, 100 lines are read at a time. If the read operation fails, a maximum of three retries are allowed. 
      for (int retry_time = 0; retry_time < 3; retry_time++) {
            GetLogsRequest req4 = new GetLogsRequest(project, logstore, from, to, topic, query, log_offset,
                 log_line, false);
            res4 = client.GetLogs(req4);
            if (res4 != null && res4.IsCompleted()) {
                      break;
                  }
                  Thread.sleep(200);
              }
              System.out.println("Read log count:" + String.valueOf(res4.GetCount()));
              log_offset += log_line;
              if (res4.IsCompleted() && res4.GetCount() == 0) {
                          break;
              }
   }                    

Paginate analysis results

limit Offset, Line

The following list describes the offset and line parameters:

• offset: the line from which analysis results are read.

• line: the number of lines that are returned for the current API request. A maximum of 1,000,000 lines can be returned. If a large number of lines are read at a time, the network delay increases, and the client-side processing speed decreases.

For example, if you want to use the * | select count(1) , url group by url statement to return 2,000 lines, you can execute the following statements to perform 4 paged queries and query 500 lines each time:

* | select count(1) , url  group by url  limit 0, 500
* | select count(1) , url  group by url  limit 500, 500
* | select count(1) , url  group by url  limit 1000, 500
* | select count(1) , url  group by url  limit 1500, 500

• Sample code for pagination

  offset = 0     // Read logs from line 0. 
  line = 500    // Read 500 lines at a time. 
  query = "* | select count(1) , url  group by url  limit "
  while True:
  real_query = query + offset + "," +  line
  response = get_logstore_logs(real_query) // Call the operation to read logs. 
  process (response)                       // Call custom logic to process the returned result. 
  if response.get_count() == 0   
      The read process is complete, and the current loop ends.
  else
      offset += 500                        // The value of the offset parameter increases to 500. The next 500 lines are read.

• Sample code in Python

  For more information, see Overview of Simple Log Service SDK for Python.

  # The Simple Log Service endpoint.
  endpoint = '' 
  # Configure environment variables. In this example, the AccessKey ID and AccessKey secret are obtained from environment variables. 
  accessKeyId = os.environ.get('ALIBABA_CLOUD_ACCESS_KEY_ID', '')
  accessKey = os.environ.get('ALIBABA_CLOUD_ACCESS_KEY_SECRET', '')
  # The name of the project. 
  project = ''     
  # The name of the Logstore. 
  logstore = ''  
  client = LogClient(endpoint, accessKeyId, accessKey)
  topic = ""
  origin_query = "* | select *  limit "
  From = int(time.time()) - 600
  To = int(time.time())
  log_line = 100
  offset = 0
  while True:
      res4 = None
      query = origin_query + str(offset) + " , " + str(log_line)
      for retry_time in range(0, 3): 
          req4 = GetLogsRequest(project, logstore, From, To, topic=topic, query=query)
          res4 = client.get_logs(req4)
          if res4 is not None and res4.is_completed():
              break
          time.sleep(1)
      offset += 100 
      if res4.is_completed() and res4.get_count() == 0:
          break;
      if res4 is not None:
      # Display the execution result. 
          res4.log_print()   

• Sample code in Java

  For more information, see Overview of Simple Log Service SDK for Java.

  int log_offset = 0;
  int log_line = 500;
  String origin_query = "* | select count(1) , url  group by url  limit "
  while (true) {
              GetLogsResponse res4 = null;
              // For each offset, 500 lines are read at a time. If the read operation fails, a maximum of three retries are allowed. 
              query = origin_query + log_offset + "," + log_line;
              for (int retry_time = 0; retry_time < 3; retry_time++) {
                  GetLogsRequest req4 = new GetLogsRequest(project, logstore, from, to, topic, query);
                  res4 = client.GetLogs(req4);
  
                  if (res4 != null && res4.IsCompleted()) {
                      break;
                  }
                  Thread.sleep(200);
              }
              System.out.println("Read log count:" + String.valueOf(res4.GetCount()));
              log_offset += log_line;
              if (res4.GetCount() == 0) {
                          break;
              }
  }