How to get GemFire HTTP Session information from GemFire servers using gfsh

Products

• VMware Tanzu Gemfire

Issue/Introduction

This article describes to get GemFire HTTP Session information from GemFire servers using gfsh.

Environment

Product Version: 9.9

Resolution

Execute one of the following functions, once registered on the server, to get the GemFire Session on the GemFire server.
 

• This function is an on-region function and should be executed as follows:

execute function --id=DumpSessionsFunction --region=/gemfire_modules_sessions

import org.apache.geode.cache.Declarable;
​
import org.apache.geode.cache.execute.Function;
import org.apache.geode.cache.execute.FunctionContext;
import org.apache.geode.cache.execute.RegionFunctionContext;
​
import org.apache.geode.cache.partition.PartitionRegionHelper;
​
import org.apache.geode.modules.session.catalina.DeltaSession;
​
import java.util.Map;
​
import java.util.stream.Collectors;
​
public class DumpSessionsFunction implements Function, Declarable {
  
  public void execute(FunctionContext context) {
    RegionFunctionContext rfc = (RegionFunctionContext) context;
    Map<String,DeltaSession> region = PartitionRegionHelper.getLocalDataForContext(rfc);
    String sessions = getSessions(region);
    context.getCache().getLogger().info(sessions);
    context.getResultSender().lastResult(true);
  }
  
  private String getSessions(Map<String,DeltaSession> region) {
    String header = "This member contains the following " + region.size() + " primary sessions";
    return region.entrySet()
      .stream()
      .sorted(Map.Entry.comparingByKey())
      .map(entry -> getEntry(entry))
      .collect(Collectors.joining("\n", header, ""));
  }
​
  private String getEntry(Map.Entry<String,DeltaSession> entry) {
    DeltaSession session = entry.getValue();
    return new StringBuilder()
      .append("\t\t")
      .append(session.getClass().getSimpleName())
      .append("[")
      .append("id=").append(session.getId())
      .append("; creationTime=").append(session.getCreationTime())
      .append("; lastAccessedTime=").append(session.getLastAccessedTime())
      .append("; maxInactiveInterval=").append(session.getMaxInactiveInterval())
      .append("; sizeInBytes=").append(session.getSizeInBytes())
      .append("]")
      .toString();
  }
​
  public String getId() {
    return getClass().getSimpleName();
  }
​
  public boolean optimizeForWrite() {
    return true;
  }
}

• This function is an on-server function and should be executed as follows:

execute function --id=DumpSessionsOnServersFunction --arguments=/gemfire_modules_sessions

import org.apache.geode.cache.Declarable;
import org.apache.geode.cache.Region;
​
import org.apache.geode.cache.execute.Function;
import org.apache.geode.cache.execute.FunctionContext;
​
import org.apache.geode.cache.partition.PartitionRegionHelper;
​
import org.apache.geode.modules.session.catalina.DeltaSession;
​
import java.util.Map;
​
import java.util.stream.Collectors;
​
public class DumpSessionsOnServersFunction implements Function, Declarable {
  
  public void execute(FunctionContext context) {
    Object[] arguments = (Object[]) context.getArguments();
    String regionPath = (String) arguments[0];
    Region pr = context.getCache().getRegion(regionPath);
    Map<String,DeltaSession> lds = PartitionRegionHelper.getLocalData(pr);
    String sessions = getSessions(lds);
    context.getCache().getLogger().info(sessions);
    context.getResultSender().lastResult(true);
  }
  
  private String getSessions(Map<String,DeltaSession> region) {
    String header = "This member contains the following " + region.size() + " sessions:\n\n";
    return region.entrySet()
      .stream()
      .sorted(Map.Entry.comparingByKey())
      .map(entry -> getEntry(entry))
      .collect(Collectors.joining("\n", header, ""));
  }
​
  private String getEntry(Map.Entry<String,DeltaSession> entry) {
    DeltaSession session = entry.getValue();
    return new StringBuilder()
      .append("\t")
      .append(session.getClass().getSimpleName())
      .append("[")
      .append("id=").append(session.getId())
      .append("; creationTime=").append(session.getCreationTime())
      .append("; lastAccessedTime=").append(session.getLastAccessedTime())
      .append("; maxInactiveInterval=").append(session.getMaxInactiveInterval())
      .append("; sizeInBytes=").append(session.getSizeInBytes())
      .append("]")
      .toString();
  }
​
  public String getId() {
    return getClass().getSimpleName();
  }
​
  public boolean optimizeForWrite() {
    return true;
  }
}

 

• Executing the function will log a message such as below on GemFire Servers:

[info 2020/10/20 16:05:42.064 PDT <Function Execution Processor3> tid=0x63] This member contains the following 179 primary sessions		DeltaSession8[id=0194B9F5042979F190F495035BD5D77C; creationTime=1603235055989; lastAccessedTime=1603235055998; maxInactiveInterval=300; sizeInBytes=9181]
  DeltaSession8[id=01A1F9C0FD3F6EA0D252566185334E2E; creationTime=1603235059051; lastAccessedTime=1603235059060; maxInactiveInterval=300; sizeInBytes=9357]
  DeltaSession8[id=0353F8F6479EB9100CBDC06991FBE111; creationTime=1603235057442; lastAccessedTime=1603235057451; maxInactiveInterval=300; sizeInBytes=29382]
  DeltaSession8[id=0395408AAE89C428C368FD81A782689D; creationTime=1603235066342; lastAccessedTime=1603235066350; maxInactiveInterval=300; sizeInBytes=3837]
  DeltaSession8[id=08D8D6ABC62507C5DC051E8FCC3B3469; creationTime=1603235063275; lastAccessedTime=1603235063284; maxInactiveInterval=300; sizeInBytes=14972]
  DeltaSession8[id=09B9C260071666E9B62D275DD8F89E30; creationTime=1603235051629; lastAccessedTime=1603235051639; maxInactiveInterval=300; sizeInBytes=0]
  DeltaSession8[id=09FD30D29D4702D6E1E66295F1C701D9; creationTime=1603235060011; lastAccessedTime=1603235060020; maxInactiveInterval=300; sizeInBytes=9704]
  DeltaSession8[id=0A7CDF709E1591CD25F831E2CFC2B2B7; creationTime=1603235063794; lastAccessedTime=1603235063803; maxInactiveInterval=300; sizeInBytes=0]
  DeltaSession8[id=0BA96F44AE36878CFF862FB93E2E9798; creationTime=1603235063760; lastAccessedTime=1603235063769; maxInactiveInterval=300; sizeInBytes=19866]
  DeltaSession8[id=0F1748A03760CDDD78E2D8AA62317FD6; creationTime=1603235064985; lastAccessedTime=1603235064994; maxInactiveInterval=300; sizeInBytes=11868]
  ...

Please refer to the following link on the way to register and execute the function:
https://gemfire.docs.pivotal.io/910/geode/developing/function_exec/function_execution.html