Null status reply

[ashwani29]

This time I'm running a redis-plus-plus client on a different machine than server, However i think i've not installed redis-plus-plus correctly, i tried multiple times and download multiple versions of hiredis to make this work, but every time i compile the client with below command, i get this result as shown below:

 root@user-HP-Pavilion-Notebook:/home/user/tests/redisclient# g++ -std=c++11 -o hclient hclient.cpp -lredis++ -lhiredis
/usr/bin/ld: warning: libhiredis.so.1.0.1-dev, needed by /usr/local/lib/libredis++.so, may conflict with libhiredis.so.0.14

and while running the client, I get this error:

 terminate called after throwing an instance of 'sw::redis::ProtoError'
  what():  A null status reply
Aborted (core dumped)

As my client is using OptionalString so I tried compiling it with -stdc++=17:

root@user-HP-Pavilion-Notebook:/home/user/tests/redisclient# g++ -std=c++17 -o hclient hclient.cpp -lredis++ -lhiredis
/usr/bin/ld: warning: libhiredis.so.1.0.1-dev, needed by /usr/local/lib/libredis++.so, may conflict with libhiredis.so.0.14
/usr/bin/ld: /tmp/ccug3Swh.o: in function `sw::redis::QueuedRedis<sw::redis::PipelineImpl>::set(std::basic_string_view<char, std::char_traits<char> > const&, std::basic_string_view<char, std::char_traits<char> > const&, std::chrono::duration<long, std::ratio<1l, 1000l> > const&, sw::redis::UpdateType)':
hclient.cpp:(.text._ZN2sw5redis11QueuedRedisINS0_12PipelineImplEE3setERKSt17basic_string_viewIcSt11char_traitsIcEES9_RKNSt6chrono8durationIlSt5ratioILl1ELl1000EEEENS0_10UpdateTypeE[_ZN2sw5redis11QueuedRedisINS0_12PipelineImplEE3setERKSt17basic_string_viewIcSt11char_traitsIcEES9_RKNSt6chrono8durationIlSt5ratioILl1ELl1000EEEENS0_10UpdateTypeE]+0x77): undefined reference to `sw::redis::cmd::set(sw::redis::Connection&, std::basic_string_view<char, std::char_traits<char> > const&, std::basic_string_view<char, std::char_traits<char> > const&, long long, sw::redis::UpdateType)'
collect2: error: ld returned 1 exit status

Redis-client:

#include <sw/redis++/redis++.h>
#include <bits/stdc++.h>
#include <unistd.h>

#define ll long long 
using namespace std;
using namespace sw::redis;

int main(){

	    // ***** Pipeline *****
	    auto redis = Redis("tcp://192.168.122.36:6379");
	    // Create a pipeline.
//	    auto pipe = redis.pipeline(false);
	    int ep = 1;
	while(true){
cout<<"========================"<<ep++<<"==================================================\n";


		auto pipe = redis.pipeline(false);

	    for(int i=1; i<=1000; i++){
			string s = to_string(i);
			if(i%2 == 1){
				pipe.set(s, s);
			}
			else {
				string st = to_string(i-1);
				pipe.get(st);		
			}
	    }

	    auto pipe_replies = pipe.exec();
		
		for (int i=1; i<=1000; i++) {
		   if (i%2 == 1) {
		       auto set_result = pipe_replies.get<bool>(i-1);
			cout<<set_result<<"\n";
		   } else {
		      OptionalString get_result = pipe_replies.get<OptionalString>(i-1);
		      if (get_result)
			  cout << *get_result << endl;	
		     else
			  cout << "key does not exist" << endl;
		  		
		  }
		}	
	    pipe.discard();
	}

return 0;
}

[sewenew]

If the code works in other environment, you'd better uninstall hiredis, and redis-plus-plus completely first, and then reinstall these libraries, and try again.

It seems that libhiredis.so.1.0.1-dev is installed with apt-get or yum, and libhiredis.so.0.14 is manually installed. Another option is to manually install hiredis at a non-default location, and depend on this version.

Regards

[ashwani29]

Got it working, Thanks.