/// =-=-=-=-=-=-=-
/// @brief given the property map the properties next_child and child_vector,
/// select the next property in the vector to be tapped as the RR resc
irods::error random_get_next_child_resource(
irods::resource_child_map& _cmap,
std::string& _next_child ) {
irods::error result = SUCCESS();
// =-=-=-=-=-=-=-
// if the child map is empty then just return
if ( _cmap.size() > 0 ) {
// =-=-=-=-=-=-=-
// get the size of the map and randomly pick an index into it
double rand_number = static_cast<double>( rand() );
rand_number /= static_cast<double>( RAND_MAX );
size_t target_index = ( size_t )round( ( _cmap.size() - 1 ) * rand_number );
// =-=-=-=-=-=-=-
// child map is keyed by resource name so we need to count out the index
// and then snag the child name from the key of the hash map
size_t counter = 0;
std::string next_child;
irods::resource_child_map::iterator itr = _cmap.begin();
for ( ; itr != _cmap.end(); ++itr ) {
if ( counter == target_index ) {
next_child = itr->first;
break;
}
else {
++counter;
}
} // for itr
// =-=-=-=-=-=-=-
// assign the next_child to the out variable
_next_child = next_child;
}
return result;
} // random_get_next_child_resource
// =-=-=-=-=-=-=-
/// @brief Returns the first child resource of the specified resource
irods::error pass_thru_get_first_chid_resc(
irods::resource_child_map& _cmap,
irods::resource_ptr& _resc ) {
irods::error result = SUCCESS();
std::pair<std::string, irods::resource_ptr> child_pair;
if ( _cmap.size() != 1 ) {
std::stringstream msg;
msg << "pass_thru_get_first_chid_resc - Passthru resource can have 1 and only 1 child. This resource has " << _cmap.size();
result = ERROR( -1, msg.str() );
}
else {
child_pair = _cmap.begin()->second;
_resc = child_pair.second;
}
return result;
} // pass_thru_get_first_chid_resc
/// =-=-=-=-=-=-=-
/// @brief find the next valid child resource for create operation
irods::error get_next_valid_child_resource(
irods::plugin_property_map& _prop_map,
irods::resource_child_map& _cmap,
irods::resource_ptr& _resc ) {
// =-=-=-=-=-=-=-
// counter and flag
int child_ctr = 0;
bool child_found = false;
// =-=-=-=-=-=-=-
// while we have not found a child and have not
// exhausted all the children in the map
while ( !child_found &&
child_ctr < _cmap.size() ) {
// =-=-=-=-=-=-=-
// increment child counter
child_ctr++;
// =-=-=-=-=-=-=-
// get the next_child property
std::string next_child;
irods::error err = _prop_map.get< std::string >( NEXT_CHILD_PROP, next_child );
if ( !err.ok() ) {
return PASSMSG( "round_robin_redirect - get property for 'next_child' failed.", err );
}
// =-=-=-=-=-=-=-
// get the next_child resource
if ( !_cmap.has_entry( next_child ) ) {
std::stringstream msg;
msg << "child map has no child by name [";
msg << next_child << "]";
return PASSMSG( msg.str(), err );
}
// =-=-=-=-=-=-=-
// request our child resource to test it
irods::resource_ptr resc = _cmap[ next_child ].second;
// =-=-=-=-=-=-=-
// get the resource's status
int resc_status = 0;
err = resc->get_property<int>( irods::RESOURCE_STATUS, resc_status );
if ( !err.ok() ) {
return PASSMSG( "failed to get property", err );
}
// =-=-=-=-=-=-=-
// determine if the resource is up and available
if ( INT_RESC_STATUS_DOWN != resc_status ) {
// =-=-=-=-=-=-=-
// we found a valid child, set out variable
_resc = resc;
child_found = true;
}
else {
// =-=-=-=-=-=-=-
// update the next_child as we do not have a valid child yet
err = update_next_child_resource( _prop_map );
if ( !err.ok() ) {
return PASSMSG( "update_next_child_resource failed", err );
}
}
} // while
// =-=-=-=-=-=-=-
// return appropriately
if ( child_found ) {
return SUCCESS();
}
else {
return ERROR( NO_NEXT_RESC_FOUND, "no valid child found" );
}
} // get_next_valid_child_resource
/// =-=-=-=-=-=-=-
/// @brief build a sorted list of children based on hints in the context
/// string for them and their positoin in the child map
// NOTE :: this assumes the order in the icat dictates the order of the RR.
// the user can override that behavior with applying an index to the
// child. should the resc id wrap, this should still work as it
// should behave like a circular queue.
irods::error build_sorted_child_vector(
irods::resource_child_map& _cmap,
std::vector< std::string >& _child_vector ) {
// =-=-=-=-=-=-=-
// vector holding all of the children
size_t list_size = _cmap.size();
_child_vector.resize( list_size );
// =-=-=-=-=-=-=-
// iterate over the children and look for indicies on the
// childrens context strings. use those to build the initial
// list.
irods::resource_child_map::iterator itr;
for ( itr = _cmap.begin();
itr != _cmap.end();
++itr ) {
std::string ctx = itr->second.first;
irods::resource_ptr& resc = itr->second.second;
if ( !ctx.empty() ) {
try {
// =-=-=-=-=-=-=-
// cast std::string to int index
size_t idx = boost::lexical_cast<int>( ctx );
if ( idx < 0 || idx >= list_size ) {
irods::log( ERROR( -1, "build_sorted_child_vector - index < 0" ) );
continue;
}
// =-=-=-=-=-=-=-
// make sure the map at this spot is already empty, could have
// duplicate indicies on children
if ( !_child_vector[ idx ].empty() ) {
std::stringstream msg;
msg << "build_sorted_child_vector - child map list is not empty ";
msg << "for index " << idx << " colliding with [";
msg << _child_vector[ idx ] << "]";
irods::log( ERROR( -1, msg.str() ) );
continue;
}
// =-=-=-=-=-=-=-
// snag child resource name
std::string name;
irods::error ret = resc->get_property< std::string >( irods::RESOURCE_NAME, name );
if ( !ret.ok() ) {
irods::log( ERROR( -1, "build_sorted_child_vector - get property for resource name failed." ) );
continue;
}
// =-=-=-=-=-=-=-
// finally add child to the list
_child_vector[ idx ] = name;
}
catch ( boost::bad_lexical_cast const& ) {
irods::log( ERROR( -1, "build_sorted_child_vector - lexical cast failed" ) );
}
} // if ctx != empty
} // for itr
// =-=-=-=-=-=-=-
// iterate over the children again and add in any in the holes
// left from the first pass
for ( itr = _cmap.begin();
itr != _cmap.end();
++itr ) {
std::string ctx = itr->second.first;
irods::resource_ptr& resc = itr->second.second;
// =-=-=-=-=-=-=-
// skip any resource whose context is not empty
// as they should have places already
if ( !ctx.empty() ) {
continue;
}
// =-=-=-=-=-=-=-
// iterate over the _child_vector and find a hole to
// fill in with this resource name
bool filled_flg = false;
size_t idx = 0;
std::vector< std::string >::iterator vitr;
for ( vitr = _child_vector.begin();
vitr != _child_vector.end();
++vitr ) {
if ( vitr->empty() ) {
// =-=-=-=-=-=-=-
// snag child resource name
std::string name;
irods::error ret = resc->get_property< std::string >( irods::RESOURCE_NAME, name );
if ( !ret.ok() ) {
irods::log( ERROR( -1, "build_sorted_child_vector - get property for resource name failed." ) );
idx++;
continue;
}
( *vitr ) = name;
filled_flg = true;
break;
}
else {
idx++;
}
} // for vitr
// =-=-=-=-=-=-=-
// check to ensure that the resc found its way into the list
if ( false == filled_flg ) {
irods::log( ERROR( -1, "build_sorted_child_vector - failed to find an entry in the resc list" ) );
}
} // for itr
return SUCCESS();
} // build_sorted_child_vector