91 lines
3.4 KiB
C++
91 lines
3.4 KiB
C++
/*
|
|
* Copyright (C) 2008 Patrick Ohly
|
|
*/
|
|
|
|
#ifndef INCL_EVOLUTION_CONFIG_TREE
|
|
# define INCL_EVOLUTION_CONFIG_TREE
|
|
|
|
#include <boost/shared_ptr.hpp>
|
|
#include <map>
|
|
#include <list>
|
|
#include <string>
|
|
using namespace std;
|
|
|
|
class ConfigNode;
|
|
|
|
/**
|
|
* This class organizes the access to config nodes in a tree. Nodes
|
|
* are identified by a relative path name, using a slash / as
|
|
* separator between levels. Each node can have user-visible and
|
|
* hidden properties. The two sets might be stored in the same
|
|
* ConfigNode, i.e. properties should have unique names per node. For
|
|
* each path there's also a second, separate namespace of key/value
|
|
* pairs. The intented use for that is saving state by sync sources
|
|
* close to, but without interfering with their configuration and the
|
|
* state maintained by the client library itself.
|
|
*
|
|
* A ConfigNode can list all its properties while the tree lists nodes
|
|
* at a specific level and creates nodes.
|
|
*
|
|
* This model is similar to the Funambol C++ DeviceManagementTree.
|
|
* Besides being implemented differently, it also provides additional
|
|
* functionality:
|
|
* - the same node can be opened more than once; in the client library
|
|
* the content of multiple instances is not synchronized and changes
|
|
* can get lost
|
|
* - nodes and the whole tree can be explicitly flushed
|
|
* - it distinguishes between user visible configuration options and
|
|
* hidden read/write properties attached to the same path
|
|
* - in addition to these visible or hidden properties under well-known
|
|
* names there can be nodes attached to each path which can
|
|
* be used for arbitrary key/value pairs; different "other" nodes can
|
|
* be selected via an additional string
|
|
* - temporarily override values without saving them (see FilterConfigNode
|
|
* decorator)
|
|
* - improved access to properties inside nodes (iterating, deleting)
|
|
*/
|
|
class ConfigTree {
|
|
public:
|
|
/** frees all resources *without* flushing changed nodes */
|
|
virtual ~ConfigTree() {}
|
|
|
|
/** ensure that all changes are saved persistently */
|
|
virtual void flush() = 0;
|
|
|
|
/** a string identifying the root of the configuration - exact meaning varies */
|
|
virtual string getRootPath() const = 0;
|
|
|
|
/**
|
|
* Selects which node attached to a path name is to be used.
|
|
* This is similar in concept to multiple data forks in a file.
|
|
*/
|
|
enum PropertyType {
|
|
visible, /**< visible configuration properties */
|
|
hidden, /**< hidden read/write properties */
|
|
other /**< additional node selected via otherID */
|
|
};
|
|
|
|
/**
|
|
* Open the specified node. Opening it multiple
|
|
* times will return the same instance, so the content
|
|
* is always synchronized.
|
|
*
|
|
* @param path a relative path with / as separator
|
|
* @param type selects which fork of that path is to be opened
|
|
* (visible, hidden, change tracking)
|
|
* @param otherId an additional string to be attached to the other
|
|
* node's name (allows having multiple different such
|
|
* nodes); an empty string is allowed
|
|
*/
|
|
virtual boost::shared_ptr<ConfigNode> open(const string &path,
|
|
PropertyType type,
|
|
const string &otherId = string("")) = 0;
|
|
|
|
/**
|
|
* returns names of all existing nodes beneath the given path
|
|
*/
|
|
virtual list<string> getChildren(const string &path) = 0;
|
|
};
|
|
|
|
#endif
|