Utility query module
Built-in utility query module (mg) contains procedures that enable you to
manage query modules files.
General procedures
Here is the list of procedures from the mg query module that can be used with
all other query module files and their signatures:
| Procedure | Description |
|---|---|
mg.procedures() -> (name|STRING, signature|STRING) | Lists loaded procedures and their signatures. |
mg.load(module_name|STRING) -> () | Loads or reloads the given module. |
mg.load_all() -> () | Loads or reloads all modules. |
mg.procedures
Lists loaded procedures and their signatures.
Example of a Cypher query:
CALL mg.procedures() YIELD *;
Example of a result:
+-------------+---------------------+-------------------+-----------------------------------------------------------------------------------------------------------------------+
| is_editable | name | path | signature |
+-------------+---------------------+-------------------+-----------------------------------------------------------------------------------------------------------------------+
| ... | ... | ... | ... |
| true | graph_analyzer.help | "/path/to/module" | graph_analyzer.help() :: (name :: STRING, value :: STRING) |
| false | mg.load | "builtin" | mg.load(module_name :: STRING) :: () |
| false | mg.load_all | "builtin" | mg.load_all() :: () |
| false | mg.procedures | "builtin" | mg.procedures() :: (name :: STRING, signature :: STRING, is_write :: BOOLEAN, path :: STRING, is_editable :: BOOLEAN) |
| ... | ... | ... | ... |
+-------------+---------------------+-------------------+-----------------------------------------------------------------------------------------------------------------------+
mg.load_all
Loads or reloads all modules.
Example of a Cypher query:
CALL mg.load_all();
If the response is Empty set (x.x sec) and there are no error messages, the
update was successful.
mg.load
Loads or reloads the given module.
Example of a Cypher query:
CALL mg.load("py_example");
If the response is Empty set (x.x sec) and there are no error messages, the
update was successful.
Procedures for .py query modules
Memgraph includes several built-in procedures for editing and inspecting Python module files.
Below is a list of the procedures, their signatures, description and required
privilege.
Privileges can be assigned only in the enterprise edition of
Memgraph.
Click on a procedure to see an example of a Cypher query and
possible result.
| Procedure | Description | Required privilege |
|---|---|---|
mg.get_module_files() -> (is_editable|STRING, path|STRING) | Returns the value of a is_editable flag and the absolute path of each Python query module file in all the query module directories. | MODULE_READ |
mg.get_module_file(path|STRING) -> (path|STRING) | Returns the content of a file located at the absolute path in one of the query module directories. | MODULE_READ |
mg.create_module_file(filename|STRING, content|STRING) -> (path|STRING) | Creates a filename Python module with content inside the internal query module directory (/var/lib/memgraph/internal_modules) and returns the path to the newly created file. The flag is_editable should be set to true if the module is located in the internal query module directory. The filename can consist of multiple nested directories (e.g. subdir1/subdir2/module.py) which will create all the necessary subdirectories. After successful creation, all the modules are reloaded. | MODULE_WRITE |
mg.update_module_file(path|STRING, content|STRING) | Updates a Python module file at an absolute path in one of the query module directories with content and reloads all the modules. You can only change the files with is_editable flag set to true. | MODULE_WRITE |
mg.delete_module_file(path|STRING) | Deletes a Python module file at an absolute path in one of the query module directories and reloads all the modules. You can only delete the files with is_editable flag set to true. | MODULE_WRITE |
mg.get_module_files
Returns the value of an is_editable flag and the absolute path of each Python
query module file in all the query module directories.
Example of a Cypher query:
CALL mg.get_module_files() YIELD *;
Example of a result:
+-----------------------------------------------------+-----------------------------------------------------+
| is_editable | path |
+-----------------------------------------------------+-----------------------------------------------------+
| false | "/usr/lib/memgraph/query_modules/mgp_networkx.py" |
| false | "/usr/lib/memgraph/query_modules/wcc.py" |
| false | "/usr/lib/memgraph/query_modules/graph_analyzer.py" |
| false | "/usr/lib/memgraph/query_modules/py_example.py" |
| false | "/usr/lib/memgraph/query_modules/nxalg.py" |
| true | "/var/lib/memgraph/internal_modules/module1.py" |
+-----------------------------------------------------+-----------------------------------------------------+
mg.get_module_file
Returns the content of a file located at the absolute path in one of the query module directories.
Example of a Cypher query:
CALL mg.get_module_file("/usr/lib/memgraph/query_modules/py_example.py") YIELD *;
mg.create_module_file
Creates a filename Python module with content inside the internal query
module directory (/var/lib/memgraph/internal_modules) and returns the path to
the newly created file. The flag is_editable should be true if the module is
located in the internal query module directory. The filename can consist of
multiple nested directories (e.g., subdir1/subdir2/module.py) and all the
necessary subdirectories will be created. After successful creation, all the
modules are reloaded.
Examples of a Cypher query:
Without defining the absolute path:
CALL mg.create_module_file("my_module.py", "Start of my query module.") YIELD *;Result:
+---------------------------------------------------+
| path |
+---------------------------------------------------+
| "/var/lib/memgraph/internal_modules/my_module.py" |
+---------------------------------------------------+With absolute path:
CALL mg.create_module_file("my_modules/my_module.py", "Start of my query module.") YIELD *;Result:
+--------------------------------------------------------------+
| path |
+--------------------------------------------------------------+
| "/var/lib/memgraph/internal_modules/my_modules/my_module.py" |
+--------------------------------------------------------------+
mg.update_module_file
Updates a Python module file at an absolute path in one of the query module
directories with content. You can only change the files with is_editable
flag set to true.
Example of a Cypher query:
CALL mg.update_module_file("/var/lib/memgraph/internal_modules/my_module.py", "Start of my query module. Another line.");
If the response is Empty set (x.x sec) and there are no error messages, the
update was successful.
mg.delete_module_file
Deletes a Python module file at an absolute path in one of the query module
directories and reloads all the modules. You can only delete the files with
is_editable flag set to true.
Example of a Cypher query:
CALL mg.delete_module_file("/var/lib/memgraph/internal_modules/my_module.py");
If the response is Empty set (x.x sec) and there are no error messages, the
update was successful.