Graphite Engine API Reference¶

A database with its own data. Can be used multiple times to create multiple databases.

Create a new instance with:

import graphite

engine = graphite.engine()

Methods:

all_shortest_paths –

All shortest paths from from_node to to_end.
bfs –

Highly Customizable BFS
clear –

Clears all current structure and data.
connected_components –

Splits given nodes to connected components.
create_node –

Creates a node instance.
create_relation –

Creates a relation instance.
define_node –

Defines a node type from DSL or directly. In DSL mode (when you just pass node_type
define_relation –

Defines a relation type from DSL or direct creation. In DSL mode (when you just pass
get_node –

Returns a node with its ID.
get_nodes_of_type –

Get all nodes of a specific type.
get_relations_from –

Returns relations from a node.
get_relations_to –

Returns relations to a node.
is_node_from_type –

Returns True if given node is from given type.
load –

Load database from a JSON file with security checks.
load_dsl –

Loads Graphite DSL to the engine.
neighborhood –

Returns neighbors of start in given max_distance.
parse –

Parses and loads data from Graphite DSL to engine.
remove_node –

Removes given nodes.
remove_nodes –

Removes given nodes and all their relations.
remove_relation –

Removes given relations.
remove_relations –

Removes given relations.
save –

Save the database to a single JSON file.
shortest_path –

Finds shortest path from from_node to to_end.
stats –

Reports count of each type of data in database.
undefine_node –

Undefines a node type, remove all referenced node types, nodes, relations type,
undefine_relation –

Undefines a relation type and its reverse relation type (if any) and relations.

Attributes:

query (QueryBuilder) –

Provides a fast and standard way to query on the engine.

Attributes¶

query `instance-attribute` ¶

query: QueryBuilder = QueryBuilder(self)

Provides a fast and standard way to query on the engine. Use engine.query.all() to query from all nodes, or engine.query.ExampleNodeType to start query from all nodes with ExampleNodeType (or another) type. In both cases, returned value is a new instance of ready-to-used QueryResult that can be chained to build complex queries. See Query Engine Tutorials for more information.

Functions¶

all_shortest_paths ¶

all_shortest_paths(from_node: Node | str, to_end: Node | str | Callable[[list[tuple[Relation, Node]]], bool] | None = None, direction: Direction = OUTGOING, relation_type: str | None = None, max_depth: int | None = None, allow_direction_switch: bool = False, ignore_nodes: set[str] | None = None, weight: str | None = None, max_results: int | None = None) -> list[tuple[str, int, list[tuple[Relation, Node]]]]

All shortest paths from from_node to to_end.

Non-weighted mode uses bfs() internally.

Wrapper

This method is a wrapper for algorithms.all_shortest_paths().

Not Implemented Completely

Weighted mode is not implemented yet.

Parameters:

from_node (Node | str) –

Starting node ID or object.
to_end (Node | str | Callable[[list[tuple[Relation, Node]]], bool] | None, default: None ) –
One of below:
- None: Match on all nodes in the result. It means all (or max_results) nearest neighbors.
- Node ID or object: Match on all paths to given node.
- Callable ((path) -> bool): Match on a path when given callable returns True.
direction (Direction, default: OUTGOING ) –

Direction to traverse.
relation_type (str | None, default: None ) –

Type of relations to limit traverse.
max_depth (int | None, default: None ) –

Maximum depth to traverse.
allow_direction_switch (bool, default: False ) –

If True allow direction switch in a path when direction=Direction.BOTH.
ignore_nodes (set[str] | None, default: None ) –

Visited set of node IDs to ignore.
weight (str | None, default: None ) –

Optional field name to weighted pathfinding.
max_results (int | None, default: None ) –

Maximum number of results to return.

Returns:

list[tuple[str, int, list[tuple[Relation, Node]]]] –
An empty list or a list of found paths sorted by distance with each item as:
```
(destination_node_id, path_depth, [(step_relation_obj, step_node_obj), ...])
                                  ^^^^^^^  path_to_destination_node  ^^^^^^^
```
path_depth is 0 for starting node, it means this is equal to the size of path_to_destination_node.

bfs ¶

bfs(start: Node | str, end: Node | str | Callable[[list[tuple[Relation, Node]]], bool] | None = None, stop_at_first: bool = True, direction: Direction = OUTGOING, relation_type: str | None = None, max_depth: int | None = None, include_start: bool = False, allow_direction_switch: bool = False, visited: set[str] | None = None, max_results: int | None = None) -> list[tuple[str, int, list[tuple[Relation, Node]]]]

Highly Customizable BFS (Breadth-First Search) in the graph.

Note

Steps are sorted by distance in returned result.

Wrapper

This method is a wrapper for algorithms.bfs().

Parameters:

start (Node | str) –

Starting node ID or object.
end (Node | str | Callable[[list[tuple[Relation, Node]]], bool] | None, default: None ) –
One of below:
- None: Match on all nodes in the result.
- Node ID or object: Match on all paths to given node.
- Callable ((path) -> bool): Match on a path when given callable returns True.
stop_at_first (bool, default: True ) –

If True and end is provided, stops at first match.
direction (Direction, default: OUTGOING ) –

Direction to traverse.
relation_type (str | None, default: None ) –

Type of relations to limit traverse.
max_depth (int | None, default: None ) –

Maximum depth to traverse.
include_start (bool, default: False ) –

If True check starting node on result.
allow_direction_switch (bool, default: False ) –

If True allow direction switch in a path when direction=Direction.BOTH.
visited (set[str] | None, default: None ) –

Visited set of node IDs to ignore.
max_results (int | None, default: None ) –

Maximum number of results to return.

Returns:

list[tuple[str, int, list[tuple[Relation, Node]]]] –
An empty list or a list of found paths sorted by distance with each item as:
```
(destination_node_id, path_depth, [(step_relation_obj, step_node_obj), ...])
                                  ^^^^^^^  path_to_destination_node  ^^^^^^^
```
path_depth is 0 for starting node, it means this is equal to the size of path_to_destination_node.

clear ¶

clear() -> None

Clears all current structure and data.

connected_components ¶

connected_components(nodes: Node | str | set[Node | str] | None = None, return_all_nodes: bool = False, direction: Direction = OUTGOING, relation_type: str | None = None, allow_direction_switch: bool = False, ignore_nodes: set[str] | None = None) -> list[set[str]]

Splits given nodes to connected components.

Wrapper

This method is a wrapper for algorithms.connected_components().

Note

Uses bfs() internally.

Parameters:

nodes (Node | str | set[Node | str] | None, default: None ) –

One or a set of node (objects or IDs) to group, or None to get all nodes from engine.
return_all_nodes (bool, default: False ) –

If True, includes all nodes in each component, not just intersection of them with input nodes. Has no effect when nodes = None. False is unusual when using a single node.
direction (Direction, default: OUTGOING ) –

Direction to traverse.
relation_type (str | None, default: None ) –

Type of relations to allow traverse.
allow_direction_switch (bool, default: False ) –

If True, allow direction switch in a path when direction = Direction.BOTH.
ignore_nodes (set[str] | None, default: None ) –

Node IDs to ignore.

Returns:

list[set[str]] –

List of component nodes.

create_node ¶

create_node(node_type: str, node_id: str, *values: Any, parse_fields: bool = False) -> Node

Creates a node instance.

Note

You can use DSL to create nodes, with parse() method:

engine.parse("""
    Person, alice, 'Alice', 32, 'alice@emial.com'
    Person, bob, "Bob", 28, 'bob.mail@email.com'
""")

This is same as:

engine.create_node("Person", "alice", "Alice", 32, "alice@emial.com")
engine.create_node("Person", "bob", "Bob", 28, "bob.mail@email.com")

Advantage is that you can do any number of node creation and other data manipulation with passing a multi-line value to parse().

Parameters:

node_type (str) –

Node type name, defined with define_node() or parse().
node_id (str) –

Node ID.
*values (Any, default: () ) –
Values for node fields.
Note

Count of values passed to values must be same as node type definition. Node types inheritance from base types define with from ... or parent parameter in define_node(); So if you have a Person node type and a User node type inherited from it like this:
```
node Person
        name: string
        age: int

node User from Person
        username: string
        email: string
```
You should pass values as <name>, <age>, <username>, <email> (4 values) when you need to create a node from User type.
parse_fields (bool, default: False ) –

If True, parse field values from raw strings.

Note

Date values will be parsed automatically, even when parse_fields is False.

Returns:

Node –

Node instance added to engine.

Raises:

NotFoundError –

If node_type not defined.
InvalidPropertiesError –

If values count is not same as node type field count.
FieldError –

If values fail in parsing, converting, or validation.

create_relation ¶

create_relation(from_id: str, to_id: str, rel_type: str, *values: Any, parse_fields: bool = False) -> Relation

Creates a relation instance.

Note

You can use DSL to create relations, with parse() method:

engine.parse("alice -[WORKS_AT, 'Designer', 120000, 2026-01-07]-> google")

This is same as:

engine.create_relation(
    "alice",
    "google",
    "WORKS_AT",
    "Designer", 120000, 2026-01-07 # or date(2026, 1, 7), will be parsed automatically.
)

Advantage is that you can do any number of relation creation and other data manipulation with passing a multi-line value to parse().

Parameters:

from_id (str) –

Source node's ID.
to_id (str) –

Target node's ID.
rel_type (str) –

Relation type name, defined with define_relation() or parse().
*values (Any, default: () ) –

Values for relation fields.
parse_fields (bool, default: False ) –

If True, parse field values from raw strings.

Note

Date values will be parsed automatically, even when parse_fields is False.

Returns:

Relation –

Created relation instance, added to editor.

Raises:

NotFoundError –

If rel_type, from_id, or to_id not defined.
InvalidRelationError –

When the type of source or target node doesn't match relation
InvalidPropertiesError –

If values count is not same as relation type field count.

Note

Relation types doesn't support inheritance, so instance's value count match the exact number of relation type's fields.
FieldError –

If values fail in parsing, converting, or validation.

define_node ¶

define_node(node_type: str, *fields: tuple[str, str], parent: str | None = None) -> None

Defines a node type from DSL or directly. In DSL mode (when you just pass node_type parameter), only supports one block starting with "node ..." (Use parse() for multiple blocks).

Example

engine.define_node("""
    node Person
        name: string
        age: int
""")
# Same as above:
engine.define_node(
    "Person",
    ("name", "string"),
    ("age", "int")
)

Parameters:

node_type (str) –

Node definition string in Graphite DSL or type name.
fields (tuple[str, str], default: () ) –

Fields of node type: (name, type).
parent (str | None, default: None ) –

Parent node type name, You must pass it positional.

Raises:

ParseError –

If node type definition is not valid (When passing DSL string as node_type).
NotFoundError –

If parent node type (from ...) is not found.
NotFoundError –

If any type (second) item of any fields values not found.

define_relation ¶

define_relation(relation_type: str, source_type: str | None = None, target_type: str | None = None, *fields: tuple[str, str], reverse_name: str | None = None, is_bidirectional: bool = False) -> None

Defines a relation type from DSL or direct creation. In DSL mode (when you just pass relation_type parameter), only supports one block starting with "relation ..." (Use parse() for multiple blocks).

Example

engine.define_relation("""
    node WORKS_AT
        Person -> Company
        position: string
        salary: int
        since: date
""")
# Same as above:
engine.define_relation(
    "WORKS_AT",
    "Person",
    "Company",
    ("position", "string"),
    ("salary", "int"),
    ("since", "date")
)

Parameters:

relation_type (str) –

Relation definition string in Graphite DSL or type name.
source_type (str | None, default: None ) –

Valid source node type name.
target_type (str | None, default: None ) –

Valid target node type name.
*fields (tuple[str, str], default: () ) –

Fields of relation type: (name, type).
reverse_name (str | None, default: None ) –

Reverse relation name (if any).
is_bidirectional (bool, default: False ) –

Is bidirectional relation or not.

Raises:

ParseError –

If relation definition is not valid.
ParseError –

If omit source_type or target_type outside DSL mode.
RelationTypeDefineError –

If relation type DSL have both reverse ... section and both flag.
NotFoundError –

If source or target node types are not found.
NotFoundError –

If any type (second) item of any fields values not found.

get_node ¶

get_node(node_id: str) -> Node

Returns a node with its ID.

Parameters:

node_id (str) –

Target node ID string.

Returns:

Node –

Node object.

Raises:

NotFoundError –

If node_id not defined.

get_nodes_of_type ¶

get_nodes_of_type(node_type: str, with_subtypes: bool = True) -> set[Node]

Get all nodes of a specific type.

Parameters:

node_type (str) –

Node type name.
with_subtypes (bool, default: True ) –

If with_subtypes is True, adds all subtypes of given node type recursively to the result.

Returns:

set[Node] –

Set of node objects

Raises:

NotFoundError –

If node_type not defined.

get_relations_from ¶

get_relations_from(node_id: str, rel_type: str | None = None) -> set[Relation]

Returns relations from a node.

Parameters:

node_id (str) –

Node ID string.
rel_type (str | None, default: None ) –

Relation type to filter on, or None to accept all types.

Returns:

set[Relation] –

Set of relations.

Raises:

NotFoundError –

If rel_type or node_id not defined.

get_relations_to ¶

get_relations_to(node_id: str, rel_type: str | None = None) -> set[Relation]

Returns relations to a node.

Parameters:

node_id (str) –

Node ID string.
rel_type (str | None, default: None ) –

Relation type to filter on, or None to accept all types.

Returns:

set[Relation] –

Set of relations.

Raises:

NotFoundError –

if rel_type or node_id not defined

is_node_from_type ¶

is_node_from_type(node_id: str, node_type: str) -> bool

Returns True if given node is from given type.

Note

This method considers type inheritance, so in this database:

type Person
    → type User
        → instance alice

Alice is from User type and any User is a Person, so

is_node_from_type(
'alice',
'Person')

returns True. If you need a direct inheritance check use alice.type_name == ..., which returns False for "Person".

Parameters:

node_id (str) –

Node ID.
node_type (str) –

Node type name.

Returns:

bool –

True if given node is from given type otherwise False.

Raises:

NotFoundError –

If given node_id or node_type not defined.

load ¶

load(file_path: str, max_size_mb: int | float | None = 100, validate_schema: bool = True, accept_any_extension: bool = False) -> None

Load database from a JSON file with security checks.

Caution

This method will call clear() before loading data to database, it means all current data will be removed.

Parameters:

file_path (str) –

File path to load.
max_size_mb (int | float | None, default: 100 ) –

Maximum allowed file size in MB, or None to disable check.
validate_schema (bool, default: True ) –

Validates schema consistency if True.
accept_any_extension (bool, default: False ) –

If True, accept any file extension, otherwise just .json is valid.

Raises:

FileSizeError –

For files bigger than max_size_mb when provided.
SafeLoadExtensionError –

For files without .json extension when accept_any_extension is True.
InvalidJSONError –

For error at decoding process.
TooNestedJSONError –

For recursion error (is almost impossible).
ValidationError –

For invalid schema when schema validate_schema is True.

load_dsl ¶

load_dsl(dsl: str) -> None

Loads Graphite DSL to the engine.

Deprecated

This method is deprecated, use parse() instead. Internally uses new method.

neighborhood ¶

neighborhood(start: Node | str, max_distance: int | None = None, filter_method: Callable[[list[tuple[Relation, Node]]], bool] | None = None, max_results: int | None = None, direction: Direction = OUTGOING, relation_type: str | None = None, allow_direction_switch: bool = False, ignore_nodes: set[str] | None = None) -> tuple[set[tuple[Node, int]], set[Relation]]

Returns neighbors of start in given max_distance.

Wrapper

This method is a wrapper for algorithms.neighborhood().

Note

Uses bfs() internally.

Parameters:

start (Node | str) –

Starting node object or ID.
max_distance (int | None, default: None ) –

Maximum distance to traverse.
filter_method (Callable[[list[tuple[Relation, Node]]], bool] | None, default: None ) –

Optional callable to filter neighbors ((path) -> bool).
max_results (int | None, default: None ) –

Maximum number of results to return.
direction (Direction, default: OUTGOING ) –

Direction to traverse.
relation_type (str | None, default: None ) –

Type of relations to allow traverse.
allow_direction_switch (bool, default: False ) –

If True, allow direction switch in a path when direction = Direction.BOTH.
ignore_nodes (set[str] | None, default: None ) –

Node IDs to ignore.

Returns:

tuple[set[tuple[Node, int]], set[Relation]] –

Set of neighbors (including start) with their distance to start, and set of relations in neighborhood.

parse ¶

parse(data: str) -> None

Parses and loads data from Graphite DSL to engine.

See DSL Reference for syntax and specification.

Parameters:

data (str) –

Data as Graphite DSL string.

Raises:

ParseError –

When failed to parse data.

Note

This method is semi-atomic, it means it will apply changes for each block and then goes to next block. When any errors occur in a block , blocks above it are applied to the engine. So it's recommend to use this method just once for an engine.
NotFoundError –

If parent node type (from ...) is not found when defining a node type. NotFoundError: If any invalid data type used in fields when defining a node type or relation type.
RelationTypeDefineError –

If relation type DSL have both reverse ... section and both flag when defining a relation type..
NotFoundError –

If source or target node types are not found when defining a relation type.
InvalidPropertiesError –

If values count is not same as node type or relation type field count when creating a node or relation.
FieldError –

If values fail in parsing, converting, or validation when creating a node or relation.
NotFoundError –

If relation type, source node ID, or target node ID not found when creating a relation.
InvalidRelationError –

When the type of source or target node doesn't match relation type signature when creating a relation.

remove_node ¶

remove_node(node: Node | str | list[Node | str]) -> None

Removes given nodes.

Deprecated

This method is deprecated, use remove_nodes() instead. Internally uses new method.

remove_nodes ¶

remove_nodes(nodes: Node | str | set[Node | str] | list[Node | str] | set[Node] | set[str] | list[Node] | list[str]) -> None

Removes given nodes and all their relations.

Important

When removing multiple nodes, this method is significantly faster than calling it repeatedly because indexes are rebuilt only once.

Parameters:

nodes (Node | str | set[Node | str] | list[Node | str] | set[Node] | set[str] | list[Node] | list[str]) –

Node ID or object(s) to remove.

Raises:

NotFoundError –

If any node is not found.

remove_relation ¶

remove_relation(relation: Relation | set[Relation] | list[Relation]) -> None

Removes given relations.

Deprecated

This method is deprecated, use remove_relations() instead. Internally uses new method.

remove_relations ¶

remove_relations(relations: Relation | set[Relation] | list[Relation]) -> None

Removes given relations.

Parameters:

relations (Relation | set[Relation] | list[Relation]) –

Relation object(s) to remove.

Raises:

NotFoundError –

If any relation is not found.

save ¶

save(file_path: str) -> None

Save the database to a single JSON file.

Parameters:

file_path (str) –

File path to save.

shortest_path ¶

shortest_path(from_node: Node | str, to_end: Node | str | Callable[[list[tuple[Relation, Node]]], bool] | None = None, direction: Direction = OUTGOING, relation_type: str | None = None, max_depth: int | None = None, allow_direction_switch: bool = False, ignore_nodes: set[str] | None = None, weight: str | None = None) -> tuple[str, int, list[tuple[Relation, Node]]] | None

Finds shortest path from from_node to to_end.

Non-weighted mode uses bfs() internally.

Wrapper

This method is a wrapper for algorithms.shortest_path().

Not Implemented Completely

Weighted mode is not implemented yet.

Parameters:

from_node (Node | str) –

Starting node Id or object.
to_end (Node | str | Callable[[list[tuple[Relation, Node]]], bool] | None, default: None ) –
One of below:
- None: Match on all nodes in the result. It means nearest neighbor.
- Node ID or object: Match on all paths to given node.
- Callable ((path) -> bool): Match on a path when given callable returns True.
direction (Direction, default: OUTGOING ) –

Direction to traverse.
relation_type (str | None, default: None ) –

Type of relations to allow traverse.
max_depth (int | None, default: None ) –

Maximum depth to traverse.
allow_direction_switch (bool, default: False ) –

If True allow direction switch in a path when direction = Direction.BOTH.
ignore_nodes (set[str] | None, default: None ) –

Node IDs to ignore.
weight (str | None, default: None ) –

Optional field name to weighted pathfinding. (Not implemented yet)

Returns:

tuple[str, int, list[tuple[Relation, Node]]] | None –

None or the shortest found path as:

(destination_node_id, path_depth, [(step_relation_obj, step_node_obj), ...])
                                  ^^^^^^^  path_to_destination_node  ^^^^^^^

path_depth is 0 for starting node, it means this is equal to the size of path_to_destination_node.

stats ¶

stats() -> dict[str, Any]

Reports count of each type of data in database.

Returns:

dict[str, Any] –

Dictionary of statistics:
dict[str, Any] –

```python
dict[str, Any] –

{ 'node_types': , 'relation_types': , 'nodes': , 'relations': ,
dict[str, Any] –

}
dict[str, Any] –

```

undefine_node ¶

undefine_node(node_type: str) -> None

Undefines a node type, remove all referenced node types, nodes, relations type, and relations.

Parameters:

node_type (str) –

Node type name.

Raises:

NotFoundError –

If node_type not defined.

undefine_relation ¶

undefine_relation(relation_type: str, _is_reverse: bool = False) -> None

Undefines a relation type and its reverse relation type (if any) and relations.

Parameters:

relation_type (str) –

Relation type name.

Other Parameters:

_is_reverse (bool) –

For internal use to remove reverse direction relation type.

Hack: Undefine a type without undefining its reverse relation type

You can disable deletion of reverse relation type with passing True to this parameter, but this can lead to unpredictable results.

Raises:

NotFoundError –

if relation_type not defined

Graphite Engine API Reference¶

Attributes¶

query instance-attribute ¶

Functions¶

all_shortest_paths ¶

bfs ¶

clear ¶

connected_components ¶

create_node ¶

create_relation ¶

define_node ¶

define_relation ¶

get_node ¶

get_nodes_of_type ¶

get_relations_from ¶

get_relations_to ¶

is_node_from_type ¶

load ¶

load_dsl ¶

neighborhood ¶

parse ¶

remove_node ¶

remove_nodes ¶

remove_relation ¶

remove_relations ¶

save ¶

shortest_path ¶

stats ¶

undefine_node ¶

undefine_relation ¶

query `instance-attribute` ¶