Checks Python API Helper Scripts

Liquibase provides an API that contains helper scripts to enable users to write Python custom policy checks. You can implement any of the helper scripts listed below into your custom policy check to narrow down the content you are searching for. Learn more about how to use these functions by reading our Custom Policy Checks documentation.

Changeset attributes

Methods to return Liquibasechangeset attributes

Function	Definition	Input Parameter
get_author(changeset)	Returns the changeset author	changeset
get_contexts(changeset)	Returns the changeset contexts	changeset
get_file_path(changeset)	Returns the changeset file path	changeset
get_id(changeset)	Returns the changeset ID	changeset
get_labels(changeset)	Returns the changeset labels	changeset
is_always_run(changeset)	Returns the changeset alwaysRun value	changeset
is_run_on_change(changeset)	Returns the changeset runOnChange value	changeset

Database attributes

Methods to return database attributes

Function	Definition	Input Parameter
get_database_product_name(database)	Returns the database product name	database
get_database_product_version(database)	Returns the database product version	database
get_default_schema_name(database)	Returns the default schema for this database	database
get_short_name(database)	Returns the database short name	database

JSON snapshot and return Dict objects

Methods to parse a JSON snapshot and return Dict objects

Function	Definition	Input Parameter
get_column(snapshot, table_name, column_name)	Return the specified Column Dict object for a table	snapshot: the snapshot to parse table_name: the name of the table to search for column_name: the name of the column to search for
get_column_size(column)	Return the specified Column's size	column: the Column Dict object
get_column_type_name(column)	Return the specified Column's type name	column: the Column Dict object
get_columns(snapshot, table_name)	Return a list of Column Dict objects for a table	snapshot: the snapshot to parse table_name: the name of the table to search for
get_indexes(snapshot, table_name)	Return a List of Index Dict objects for a table	snapshot: the snapshot to parse table_name: the name of the table to search for
get_primary_key(snapshot, table_name)	Return a Primary Key Dict object for a table	snapshot: the snapshot to parse table_name: the name of the table to search for
get_table(snapshot, table_name)	Return a list of Table Dict objects	snapshot: the snapshot to parse table_name: the name of the table to search for
get_tables(snapshot)	Return a list of Table Dict objects	snapshot: the snapshot to parse

Liquibase utilities

Utilities are general script helpers that retrieve content frequently searched for.

Function	Definition	Input Parameter
generate_sql(change)	Generate the SQL for this change and database	change: the change to generate sql from return: the sql of the change
get_arg(name)	Return the value of script argument	name: the argument to find return: the value of the argument
get_binding(key)	Access the binding object at the given key	key: the binding to access return: the binding
get_cache(key, default_value)	Return the results cache Dict object from the bindings if there is no current value then put the default value	key: the look up key default_value: the value to put for the key if no value present return: the current value or the default
get_changes()	Return a list of Liquibase Change objects	return: the liquibase change objects
get_changeset()	Return the Liquibase Change Set object	return: the liquibase change set object
get_column_type(database_object)	Get the type of the column of a database object	database_object: the database object return: the type of the column, or None if the database object is not a column
get_database()	Get the liquibase database object	return: the liquibase database object
get_database_object()	Return the DatabaseObject that is being referenced in a database-scoped check	return: the current database object being checked
get_database_snapshot()	Return the DatabaseSnapshot as a String	return: the database snapshot string
get_dbutil()	Return the dbutil object used to check for object existence or to snapshot the DatabaseObject and return it	return: the db_util object
get_logger()	Get the liquibase logger	return: the liquibase logger
get_object_type_name(database_object)	Get the object type string of a given database object	database_object: The database_object to return the type for return: the type as a string
get_script_message()	Get the message for the script	return: the message
get_script_path()	Return the path of the script	return: the path of the script
get_snapshot()	Return the snapshot as a JSON object.	return: The snapshot json object or None if no snapshot is available
get_status()	Return the Status object which will be used to set the check fired status and return a message	return: the status object
has(object_type, schema_name, object_name)	Returns true if there is an object of this type and name in the schema	object_type: the object type schema_name: the schema name object_name: the object name return: true if there is an object that matches this description, false otherwise
has_relation(object_type, object_name, relation_type, relation_schema_name, relation_name)	Returns true if there is an object of this type that has a relation object that matches the relation type, schema, and name	object_type: the object type object_name: the object name relation_type: the type of relation (Table or View) relation_schema_name: the schema of the relation object relation_name: the name of the relation return: Returns true if there is an object of this type that has a relation object that matches the relation type, schema, and name. Returns false if no items match the provided criteria.
is_catalog(database_object)	Check if the database object is a catalog	database_object: the database object to check return: true if the object is a catalog, false otherwise
is_check_constraint(database_object)	Check if the database object is a check constraint	database_object: the database object to check return: true if the object is a check constraint, false otherwise
is_column(database_object)	Check if the database object is a column	database_object: the database object to check return: true if the object is a column, false otherwise
is_database_package(database_object)	Check if the database object is a database package	database_object: the database object to check return: true if the object is a database package, false otherwise
is_database_package_body(database_object)	Check if the database object is a database package body	database_object: the database object to check return: true if the object is a database package body, false otherwise
is_foreign_key(database_object)	Check if the database object is a foreign key	database_object: the database object to check return: true if the object is a foreign key, false otherwise
is_function(database_object)	Check if the database object is a function	database_object: the database object to check return: true if the object is a function, false otherwise
is_index(database_object)	Check if the database object is a index	database_object: the database object to check return: true if the object is a index, false otherwise
is_primary_key(database_object)	Check if the database object is a primary key	database_object: the database object to check return: true if the object is a primary key, false otherwise
is_schema(database_object)	Check if the database object is a schema	database_object: the database object to check return: true if the object is a schema, false otherwise
is_sequence(database_object)	Check if the database object is a sequence	database_object: the database object to check return: true if the object is a sequence, false otherwise
is_stored_database_logic(database_object)	Check if the database object is stored database logic	database_object: the database object to check return: true if the object is stored database logic, false otherwise
is_stored_procedure(database_object)	Check if the database object is a stored procedure	database_object: the database object to check return: true if the object is a stored procedure, false otherwise
is_synonym(database_object)	Check if the database object is a synonym	database_object: the database object to check return: true if the object is a synonym, false otherwise
is_table(database_object)	Check if the database object is a table	database_object: the database object to check return: true if the object is a table, false otherwise
is_trigger(database_object)	Check if the database object is a trigger	database_object: the database object to check return: true if the object is a trigger, false otherwise
is_unique_constraint(database_object)	Check if the database object is a unique constraint	database_object: the database object to check return: true if the object is a unique constraint, false otherwise
is_view(database_object)	Check if the database object is a view	database_object: the database object to check return: true if the object is a view, false otherwise
put_cache(key, value)	Put the value in the cache	key The key to use value The value to put in the cache
query_for_list(sql, sql_file, end_delimiter)	Execute a SQL statement or script	sql: the sql to execute sql_file: the sql file to execute end_delimiter: the end delimiter to use return: the results of the sql as a list
snapshot_object(object_type, object_name, relation_type, schema_name, relation_name)	Return a Liquibase model object that represents a database object	object_type: the type of the object, like Table object_name: the objects name relation_type: a type of relation that we need to snapshot to access the object schema_name: the schema for the relation relation_name: the name of the relation return: the liquibase model for the database object
split_sql(sql_string, strip_comments_flag, end_delimiter, changeset)	Returns an array of SQL lines	sql_string: the SQL to process strip_comments_flag: true to strip out comments end_delimiter: the end delimiter to use while processing the sql changeset: the change set associated with the sql return: An array of SQL lines
split_statements(sql_string)	Split a string of SQL into individual statements	sql_string: the sql string to split return: the list of sql strings
strip_comments(sql_string)	Strip comments from a SQL string	sql_string: the sql to strip return: the sql string with comments removed
tokenize(statement)	Tokenize a statement which was create by sqlparse and return a list	statement: the statement to tokenize return: the tokenized statement as a list