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// file : mod/database.cxx -*- C++ -*-
// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
// license : MIT; see accompanying LICENSE file
#include <mod/database.hxx>
#include <map>
#include <odb/pgsql/database.hxx>
#include <odb/pgsql/connection-factory.hxx>
namespace brep
{
struct db_key
{
string user;
string role;
string password;
string name;
string host;
uint16_t port;
};
static bool
operator< (const db_key& x, const db_key& y)
{
int r;
if ((r = x.user.compare (y.user)) != 0 ||
(r = x.role.compare (y.role)) != 0 ||
(r = x.password.compare (y.password)) != 0 ||
(r = x.name.compare (y.name)) != 0 ||
(r = x.host.compare (y.host)))
return r < 0;
return x.port < y.port;
}
using namespace odb;
class connection_pool_factory: public pgsql::connection_pool_factory
{
public:
connection_pool_factory (string role, size_t max_connections)
: pgsql::connection_pool_factory (max_connections),
role_ (move (role))
{
}
virtual pooled_connection_ptr
create () override
{
pooled_connection_ptr conn (pgsql::connection_pool_factory::create ());
// Set the serializable isolation level for the subsequent connection
// transactions. Note that the SET TRANSACTION command affects only the
// current transaction.
//
conn->execute ("SET default_transaction_isolation=serializable");
// Change the connection current user to the execution user name.
//
if (!role_.empty ())
conn->execute ("SET ROLE '" + role_ + "'");
return conn;
}
private:
string role_;
};
shared_ptr<database>
shared_database (string user,
string role,
string password,
string name,
string host,
uint16_t port,
size_t max_connections)
{
static std::map<db_key, weak_ptr<database>> databases;
db_key k ({
move (user), move (role), move (password),
move (name),
move (host), port});
auto i (databases.find (k));
if (i != databases.end ())
{
if (shared_ptr<database> d = i->second.lock ())
return d;
}
unique_ptr<pgsql::connection_factory>
f (new connection_pool_factory (k.role, max_connections));
shared_ptr<database> d (
make_shared<pgsql::database> (
k.user,
k.password,
k.name,
k.host,
k.port,
"",
move (f)));
databases[move (k)] = d;
return d;
}
}
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