Class GraphManager

• Defined in File graph_manager.h

Nested Relationships

Nested Types

• Struct GraphManager::HeadProperties

Class Documentation

class GraphManager

Owns the graphs in memory and the “heads”: root folders on the disk where graphs are saved. A graph with the qualifier “a.b.c” is saved in “<head>/a/b/c.graph”.

Public Types

enum class Owner

Ordered from the most personal to the least personal: when saving, the most personal writable head is used.

Values:

enumerator User

enumerator Group

enumerator Global

enumerator Unknown

using head_id_t = std::size_t

using library_t = std::map<qualifier_t, head_id_t>

using heads_t = SmallMap<head_id_t, HeadProperties>

Public Functions

GraphManager(const GraphManager&) = delete

GraphManager &operator=(const GraphManager&) = delete

~GraphManager() = default

inline const library_t &get_library() const

inline const heads_t &get_heads() const

inline const Graph &get_graph(graph_id_t id) const

Throws:

std::out_of_range – if the graph doesn’t exist.

inline Graph &get_graph(graph_id_t id)

inline bool has_graph(graph_id_t id) const

graph_id_t new_graph(const std::string &name = "")

bool close_graph(graph_id_t id)

Returns:

false if the graph doesn’t exist.

head_id_t add_head(const std::filesystem::path &path, Owner owner = Owner::User)

Registers a new head and discovers the graphs it contains.

void refresh()

Re-discovers the graphs contained in all the readable heads.

bool exists(const qualifier_t &q) const

Returns:

true if a graph with this qualifier exists in one of the heads.

Status save_graph(graph_id_t id)

Saves the graph in the most personal writable head.

Status save_graph(graph_id_t id, head_id_t head_id)

Graph raw_read(const qualifier_t &q) const

Reads a graph from the disk without registering it in the manager.

Throws:

std::runtime_error – if the graph can’t be found or read.

graph_id_t load_graph(const qualifier_t &q, bool force = false)

Loads a graph from the disk and registers it in the manager. If it was already loaded and force is false, the ID of the graph in memory is returned.

Throws:

std::runtime_error – if the graph can’t be found or read.

void reset()

Forgets everything: graphs in memory and heads. Mostly useful for tests.

Public Static Functions

static bool can_write(const std::filesystem::path &path)

static bool can_read(const std::filesystem::path &path)

static GraphManager &instance()

struct HeadProperties

Public Functions

inline HeadProperties(Owner owner = Owner::Unknown, const std::filesystem::path &path = "", bool readable = false, bool writable = false)

Public Members

Owner owner

std::filesystem::path path

bool readable

bool writable