A basic C++ demo CRUD application using the DataStax C/C++ Driver for Apache Cassandra

quickstart.cpp

#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "cassandra.h"

struct Users_ {
  const char* lastname;
  cass_int32_t age;
  const char* city;
  const char* email;
  const char* firstname;
};

typedef struct Users_ Users;

void print_error(CassFuture* future) {
  const char* message;
  size_t message_length;
  cass_future_error_message(future, &message, &message_length);
  fprintf(stderr, "Error: %.*s\n", (int)message_length, message);
}

CassCluster* create_cluster(const char* hosts) {
  CassCluster* cluster = cass_cluster_new();
  cass_cluster_set_contact_points(cluster, hosts);
  return cluster;
}

CassError connect_session(CassSession* session, const CassCluster* cluster) {
  CassError rc = CASS_OK;
  CassFuture* future = cass_session_connect(session, cluster);

  cass_future_wait(future);
  rc = cass_future_error_code(future);
  if (rc != CASS_OK) {
    print_error(future);
  }
  cass_future_free(future);

  return rc;
}

CassError insert_user(CassSession* session, const Users* users) {
  CassError rc = CASS_OK;
  CassStatement* statement = NULL;
  CassFuture* future = NULL;

  const char* query =  "INSERT INTO demo.users (lastname, age, city, email, firstname) VALUES (?, ?, ?, ?, ?)";

  statement = cass_statement_new(query, 5);

  cass_statement_bind_string(statement, 0, users->lastname);
  cass_statement_bind_int32(statement, 1, users->age);
  cass_statement_bind_string(statement, 2, users->city);
  cass_statement_bind_string(statement, 3, users->email);
  cass_statement_bind_string(statement, 4, users->firstname);

  future = cass_session_execute(session, statement);

  cass_future_wait(future);

  rc = cass_future_error_code(future);
  if (rc != CASS_OK) {
    print_error(future);
  }

  cass_future_free(future);
  cass_statement_free(statement);

  return rc;
}


CassError select_user(CassSession* session, const Users* users) {
  CassError rc = CASS_OK;
  CassStatement* statement = NULL;
  CassFuture* future = NULL;

  const char* query =  "SELECT * FROM demo.users WHERE lastname=?";

  statement = cass_statement_new(query, 1);

  cass_statement_bind_string(statement, 0, users->lastname);

  future = cass_session_execute(session, statement);
  cass_future_wait(future);

  rc = cass_future_error_code(future);
  if (rc != CASS_OK) {
    print_error(future);

  } else {
    const CassResult* result = cass_future_get_result(future);
    const CassRow* row = cass_result_first_row(result);

    if (row) {
      const CassValue* firstvalue = cass_row_get_column_by_name(row, "firstname");
           const char* firstname;
           size_t firstname_length;
           cass_value_get_string(firstvalue, &firstname, &firstname_length);

       const CassValue* secondvalue = cass_row_get_column_by_name(row, "age");
            cass_int32_t age;
            cass_value_get_int32(secondvalue, &age);

      printf("firstname: '%.*s' age: %d\n", (int)firstname_length, firstname, age);
   }

   cass_statement_free(statement);
   cass_future_free(future);

  }

  return rc;
}


CassError update_user(CassSession* session, const Users* users) {
  CassError rc = CASS_OK;
  CassStatement* statement = NULL;
  CassFuture* future = NULL;

  const char* query =  "UPDATE demo.users SET age =?  WHERE lastname =? ";

  statement = cass_statement_new(query, 2);

  cass_statement_bind_int32(statement, 0, users->age);
  cass_statement_bind_string(statement, 1, users->lastname);

  future = cass_session_execute(session, statement);

  cass_future_wait(future);

  rc = cass_future_error_code(future);
  if (rc != CASS_OK) {
    print_error(future);
  }

  cass_future_free(future);
  cass_statement_free(statement);

  return rc;
}

CassError delete_user(CassSession* session, const Users* users) {
  CassError rc = CASS_OK;
  CassStatement* statement = NULL;
  CassFuture* future = NULL;

  const char* query =  "DELETE FROM demo.users WHERE lastname=?";

  statement = cass_statement_new(query, 1);

  cass_statement_bind_string(statement, 0, users->lastname);

  future = cass_session_execute(session, statement);

  cass_future_wait(future);

  rc = cass_future_error_code(future);
  if (rc != CASS_OK) {
    print_error(future);
  }

  cass_future_free(future);
  cass_statement_free(statement);

  return rc;
}

int main(int argc, char* argv[]) {
  CassCluster* cluster = NULL;
  CassSession* session = cass_session_new();
  Users input = { "Jones", 39, "Austin", "[email protected]", "Bob" };
  Users select = { "Jones", NULL, NULL, NULL, NULL};
  Users update = { "Jones", 40, NULL, NULL, NULL};
  Users deletion = { "Jones", NULL, NULL, NULL, NULL};

  char* hosts = "127.0.0.1";
  if (argc > 1) {
    hosts = argv[1];
  }
  cluster = create_cluster(hosts);

  if (connect_session(session, cluster) != CASS_OK) {
    cass_cluster_free(cluster);
    cass_session_free(session);
    return -1;
  }

  insert_user(session, &input);
  select_user(session, &select);
  update_user(session, &update);
  delete_user(session, &deletion);


  cass_cluster_free(cluster);
  cass_session_free(session);

  return 0;
}