/// =-=-=-=-=-=-=-
/// @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 find the next valid child resource for create operation
irods::error get_next_valid_child_resource(
irods::resource_plugin_context& _ctx,
const std::string* _opr,
const std::string* _curr_host,
irods::hierarchy_parser* _out_parser,
float* _out_vote ) {
// =-=-=-=-=-=-=-
// 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 < _ctx.child_map().size() ) {
// =-=-=-=-=-=-=-
// increment child counter
child_ctr++;
// =-=-=-=-=-=-=-
// get the next_child property
std::string next_child;
irods::error err = _ctx.prop_map().get< std::string >(
NEXT_CHILD_PROP,
next_child );
if ( !err.ok() ) {
return PASSMSG( "get property for 'next_child' failed.", err );
}
// =-=-=-=-=-=-=-
// get the next_child resource
if ( !_ctx.child_map().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 = _ctx.child_map()[ 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 );
}
// =-=-=-=-=-=-=-
// forward the 'put' redirect to the appropriate child
err = resc->call < const std::string*,
const std::string*,
irods::hierarchy_parser*,
float* > (
_ctx.comm(),
irods::RESOURCE_OP_RESOLVE_RESC_HIER,
_ctx.fco(),
_opr,
_curr_host,
_out_parser,
_out_vote );
if ( !err.ok() ) {
rodsLog(
LOG_ERROR,
"forward of put redirect failed" );
continue;
}
if( *_out_vote > 0 ) {
// =-=-=-=-=-=-=-
// we found a valid child, set out variable
child_found = true;
}
else {
// =-=-=-=-=-=-=-
// update the next_child as we do not have a valid child yet
err = update_next_child_resource( _ctx.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 used to allow the resource to determine which host
/// should provide the requested operation
irods::error round_robin_redirect(
irods::resource_plugin_context& _ctx,
const std::string* _opr,
const std::string* _curr_host,
irods::hierarchy_parser* _out_parser,
float* _out_vote ) {
// =-=-=-=-=-=-=-
// check incoming parameters
irods::error err = round_robin_check_params< irods::file_object >( _ctx );
if ( !err.ok() ) {
return PASSMSG( "round_robin_redirect - bad resource context", err );
}
if ( !_opr ) {
return ERROR( SYS_INVALID_INPUT_PARAM, "round_robin_redirect - null operation" );
}
if ( !_curr_host ) {
return ERROR( SYS_INVALID_INPUT_PARAM, "round_robin_redirect - null host" );
}
if ( !_out_parser ) {
return ERROR( SYS_INVALID_INPUT_PARAM, "round_robin_redirect - null outgoing hier parser" );
}
if ( !_out_vote ) {
return ERROR( SYS_INVALID_INPUT_PARAM, "round_robin_redirect - null outgoing vote" );
}
// =-=-=-=-=-=-=-
// get the object's hier string
irods::file_object_ptr file_obj = boost::dynamic_pointer_cast< irods::file_object >( _ctx.fco() );
std::string hier = file_obj->resc_hier( );
// =-=-=-=-=-=-=-
// get the object's hier string
std::string name;
err = _ctx.prop_map().get< std::string >( irods::RESOURCE_NAME, name );
if ( !err.ok() ) {
return PASSMSG( "failed to get property 'name'.", err );
}
// =-=-=-=-=-=-=-
// add ourselves into the hierarch before calling child resources
_out_parser->add_child( name );
// =-=-=-=-=-=-=-
// test the operation to determine which choices to make
if ( irods::OPEN_OPERATION == ( *_opr ) ||
irods::WRITE_OPERATION == ( *_opr ) ) {
// =-=-=-=-=-=-=-
// get the next child pointer in the hierarchy, given our name and the hier string
irods::resource_ptr resc;
err = get_next_child_for_open_or_write(
name,
file_obj,
_ctx.child_map(),
resc );
if ( !err.ok() ) {
(*_out_vote) = 0.0;
return PASS( err );
}
// =-=-=-=-=-=-=-
// forward the redirect call to the child for assertion of the whole operation,
// there may be more than a leaf beneath us
return resc->call < const std::string*,
const std::string*,
irods::hierarchy_parser*,
float* > (
_ctx.comm(),
irods::RESOURCE_OP_RESOLVE_RESC_HIER,
_ctx.fco(),
_opr,
_curr_host,
_out_parser,
_out_vote );
std::string hier;
_out_parser->str( hier );
rodsLog(
LOG_DEBUG,
"open :: resc hier [%s] vote [%f]",
hier.c_str(),
_out_vote );
}
else if ( irods::CREATE_OPERATION == ( *_opr ) ) {
// =-=-=-=-=-=-=-
// get the next available child resource
irods::resource_ptr resc;
irods::error err = get_next_valid_child_resource(
_ctx.prop_map(),
_ctx.child_map(),
resc );
if ( !err.ok() ) {
return PASS( err );
}
// =-=-=-=-=-=-=-
// forward the 'put' redirect to the appropriate child
err = resc->call < const std::string*,
const std::string*,
irods::hierarchy_parser*,
float* > (
_ctx.comm(),
irods::RESOURCE_OP_RESOLVE_RESC_HIER,
_ctx.fco(),
_opr,
_curr_host,
_out_parser,
_out_vote );
if ( !err.ok() ) {
return PASSMSG( "forward of put redirect failed", err );
}
std::string hier;
_out_parser->str( hier );
rodsLog(
LOG_DEBUG,
"round robin - create :: resc hier [%s] vote [%f]",
hier.c_str(),
_out_vote );
std::string new_hier;
_out_parser->str( new_hier );
// =-=-=-=-=-=-=-
// update the next_child appropriately as the above succeeded
err = update_next_child_resource( _ctx.prop_map() );
if ( !err.ok() ) {
return PASSMSG( "update_next_child_resource failed", err );
}
return SUCCESS();
}
// =-=-=-=-=-=-=-
// must have been passed a bad operation
std::stringstream msg;
msg << "round_robin_redirect - operation not supported [";
msg << ( *_opr ) << "]";
return ERROR( -1, msg.str() );
} // round_robin_redirect
/// =-=-=-=-=-=-=-
/// @brief interface to notify of a file modification
irods::error round_robin_file_modified(
irods::resource_plugin_context& _ctx ) {
// =-=-=-=-=-=-=-
// get the child resc to call
irods::resource_ptr resc;
irods::error err = round_robin_get_resc_for_call< irods::file_object >( _ctx, resc );
if ( !err.ok() ) {
return PASS( err );
}
// =-=-=-=-=-=-=-
// call modified on the child
err = resc->call( _ctx.comm(), irods::RESOURCE_OP_MODIFIED, _ctx.fco() );
if ( !err.ok() ) {
return PASS( err );
}
// =-=-=-=-=-=-=-
// get the operation property, if it is a create op then we need
// to update the next child in the context string
std::string operation;
err = _ctx.prop_map().get< std::string >(
OPERATION_PROP,
operation );
if( err.ok() && irods::CREATE_OPERATION == operation ) {
// =-=-=-=-=-=-=-
// update the next_child appropriately as the above succeeded
err = update_next_child_resource( _ctx.prop_map() );
if ( !err.ok() ) {
return PASSMSG( "update_next_child_resource failed", err );
}
// =-=-=-=-=-=-=-
// if file modified is successful then we will update the next
// child in the round robin within the database
std::string name;
_ctx.prop_map().get< std::string >( irods::RESOURCE_NAME, name );
std::string next_child;
_ctx.prop_map().get< std::string >( NEXT_CHILD_PROP, next_child );
setRoundRobinContextInp_t inp;
snprintf(
inp.resc_name_,
sizeof( inp.resc_name_ ),
"%s", name.c_str() );
snprintf(
inp.context_,
sizeof( inp.context_ ),
"%s", next_child.c_str() );
int status = irods::server_api_call(
SET_RR_CTX_AN,
_ctx.comm(),
&inp,
NULL,
( void** ) NULL,
NULL );
if ( status < 0 ) {
std::stringstream msg;
msg << "failed to update round robin context for [";
msg << name << "] with context [" << next_child << "]";
return ERROR(
status,
msg.str() );
}
} // if get prop
return SUCCESS();
} // round_robin_file_modified
