To create a new extension object to provide one or more functions,
data types, or further extension objects, use the built-in
shell.createExtensionObject() function in
To add members to the extension object, use the built-in
shell.addExtensionObjectMember() function in
shell.add_extension_object_member() in Python:
shell.addExtensionObjectMember(object, name, member[, definition])
objectis the extension object where the new member is to be added.
memberis the value of the new member, which can be any of the following:
A supported basic data type. The supported data types are “none” or “null”, “bool”, “number” (integer or floating point), “string”, “array”, and “dictionary”.
Another extension object.
definitionis an optional dictionary that can contain help information for the member, and also if the member is a function, a list of parameters that the function receives. Help information is defined using the following attributes:
briefis a brief description of the member.
detailsis a detailed description of the member, provided as a list of strings. This is provided when you use the MySQL Shell
Parameters for a function are defined using the following attribute:
parametersis a list of dictionaries describing each parameter that the function receives. Each dictionary describes one parameter, and can contain the following keys:
name(string, required): The name of the parameter.
type(string, required): The data type of the parameter, one of “string”, “integer”, “bool”, “float”, “array”, “dictionary”, or “object”. If the type is “object”, the
classeskey can also be used. If the type is “string”, the
valueskey can also be used. If the type is “dictionary”, the
optionskey can also be used.
class(string, optional, allowed when data type is “object”): Defines the object type that is allowed as a parameter.
classes(list of strings, optional, allowed when data type is “object”): A list of classes defining the object types that are allowed as a parameter. The supported object types for
classesare those that are exposed by the MySQL Shell APIs, for example
Collection. An error is raised if an object type is passed to the function that is not in this list.
values(list of strings, optional, allowed when data type is “string”): A list of values that are valid for the parameter. An error is raised if a value is passed to the function that is not in this list.
options(list of options, optional, allowed when data type is “dictionary”): A list of options that are allowed for the parameter. Options use the same definition structure as the parameters, with the exception that if
requiredis not specified for an option, it defaults to
false. MySQL Shell validates the options specified by the end user and raises an error if an option is passed to the function that is not in this list. In MySQL Shell 8.0.17 through 8.0.19, this parameter is required when the data type is “dictionary”, but from MySQL Shell 8.0.20 it is optional. If you create a dictionary with no list of options, any options that the end user specifies for the dictionary are passed directly through to the function by MySQL Shell with no validation.
required(bool, optional): Whether the parameter is required. If
requiredis not specified for a parameter, it defaults to
brief(string, optional): A short description of the parameter to be provided as help information.
details(list of strings, optional): A detailed description of the parameter to be provided as help information.
An extension object is considered to be under construction until it has been registered as a MySQL Shell global object, or added as a member to another extension object that is registered as a MySQL Shell global object. An error is returned if you attempt to use an extension object in MySQL Shell when it has not yet been registered.
Table 6.1 Supported data type pairs for extension objects
An extension object is literally the same object in both languages.