How to query the provenance data?

Question: How to query the provenance data?

Answer: One way to query the provenance data generated by a provenance enabled application is to write another application - a query application and deploy it on certain nodes of the same network. The query application is basically a set of rules to query the provenance information that is collected at the nodes running the provenance enabled protocol.

• Create a provenance enabled application as described here How to create a new RapidNet NDlog application with provenance capability? Rest of this How-To's assumes the application created is myproto-prov.
• Create a rapidnet query application src/applications/myproto-query/myproto-query.olg with the following code:

materialize(records,infinity,infinity,keys(1,2:cid,3:cid)).    
materialize(tuple, infinity, infinity, keys(1,2:str,3,4)).    

q1 provQuery(@X, QID, UID, ME):- periodic(@ME,E,4,2), tuple(@ME, Name, X, Y, C), UID:=f_sha1(Name+X+Y+C),
                                 Time := f_now(), QID:=f_sha1(""+UID+Time).
q2 records(@ME, QID, RID, Prov) :- pReturn(@ME, QID, RID, Prov).

• Generate the code for both the applications using the rapidnet/compiler/compile. Note that you should not use --provenance flag for the query application.
• Now we are ready to deploy both these applications together. The following script modified from examples/mincost-query-test.cc deploys the mincost application to three nodes and the query application to one node and runs them all. Save it as examples/myproto-query-test.cc

  #include "ns3/core-module.h"
  #include "ns3/simulator-module.h"
  #include "ns3/node-module.h"
  #include "ns3/rapidnet-module.h"
  #include "ns3/values-module.h"
  #include "ns3/helper-module.h"
  #include "ns3/myproto-module.h"
  #include "ns3/myproto-query-module.h"
  #include <time.h>
  
  #define link(src, next, cost) \
    tuple (Myproto::LINK, \
      attr ("link_attr1", Ipv4Value, src), \
      attr ("link_attr2", Ipv4Value, next), \
           attr ("link_attr3", Int32Value, cost))
  
  #define insertlink(from, to, cost) \
    app(from)->Insert (link (addr (from), addr (to), cost)); \
    app(to)->Insert (link (addr (to), addr (from), cost));
  
  #define deletelink(from, to, cost) \
    app(from)->Delete (link (addr (from), addr (to), cost)); \
    app(to)->Delete (link (addr (to), addr (from), cost));
  
  //define the tuple you would like to query and how to insert it
  #define tupleQuery(loc, name, attr1, attr2, attr3)         \
    tuple (MyprotoQuery::TUPLE, \
      attr ("tuple_attr1", Ipv4Value, loc), \
      attr ("tuple_attr2", StrValue, name), \
      attr ("tuple_attr3", Ipv4Value, attr1), \
      attr ("tuple_attr4", Ipv4Value, attr2), \
           attr ("tuple_attr5", Int32Value, attr3))
  
  #define inserttuple(loc, name, attr1, attr2, attr3)     \
    queryNode->Insert (tupleQuery(queryNode->GetAddress(), name, addr(attr1), addr(attr2), attr3));
  
  
  using namespace std;
  using namespace ns3;
  using namespace ns3::rapidnet;
  using namespace ns3::rapidnet::myproto;
  using namespace ns3::rapidnet::myprotoquery;
  
  ApplicationContainer apps;
  ApplicationContainer queryapps;
  
  void
  initApps()
  {
    NodeContainer mainAppNodes;
    mainAppNodes.Create (3);
  
    NodeContainer queryAppNodes;
    queryAppNodes.Create (1);
  
    NodeContainer csmaNodes;
    csmaNodes.Add(mainAppNodes);
    csmaNodes.Add(queryAppNodes);
  
    CsmaHelper csma;
  
    NetDeviceContainer csmaDevices;
    csmaDevices = csma.Install (csmaNodes);
  
    InternetStackHelper stack;
    stack.Install (csmaNodes);
  
    Ipv4AddressHelper address;
    Ipv4Address base = "10.1.1.0";
  
    address.SetBase (base, "255.255.255.0");
    address.Assign (csmaDevices);
  
    apps.Add(Create<MyprotoHelper>()->Install(mainAppNodes));
    queryapps.Add(Create<MyprotoQueryHelper>()->Install(queryAppNodes));
  
    SetMaxJitter (apps, 0.001);
    SetMaxJitter (queryapps, 0.001);
  }
  
  void
  UpdateLinks1 ()
  {
    insertlink (1, 2, 3);
    insertlink (2, 3, 2);
    insertlink (1, 3, 5);
  }
  
  void
  TupleToQuery ()
  {
    Ptr<RapidNetApplicationBase> queryNode = queryapps.Get(0)->GetObject<RapidNetApplicationBase>();
    inserttuple(1, "bestPath", 3, 2, 2);
    inserttuple(1, "path", 1, 3, 5);
    inserttuple(1, "link", 1, 2, 3);
  }
  
  void
  Print ()
  {
    PrintRelation (apps, Myproto::BESTPATH);
    PrintRelation (apps, Myproto::PROV);
    PrintRelation (apps, Myproto::RULEEXEC);
  
    PrintRelation (queryapps, MyprotoQuery::TUPLE);
    PrintRelation (queryapps, MyprotoQuery::RECORDS);
  }
  
  int
  main (int argc, char *argv[])
  {
    LogComponentEnable("Myproto", LOG_LEVEL_INFO);
    LogComponentEnable("MyprotoQuery", LOG_LEVEL_INFO);
    LogComponentEnable("RapidNetApplicationBase", LOG_LEVEL_INFO);
  
    initApps();
  
    apps.Start (Seconds (0.0));
    apps.Stop (Seconds (5.0));
    queryapps.Start (Seconds (0.0));
    queryapps.Stop (Seconds (5.0));
  
    schedule (1.0, TupleToQuery);
    schedule (2.0, UpdateLinks1);
    schedule (5.0, Print);
  
    Simulator::Run ();
    Simulator::Destroy ();
  
    return 0;
  }
  

• Next step is to build and run using the command ./waf --run myproto-query-test