对字典列表进行排序和分组

本文介绍了对字典列表进行排序和分组的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

如何将字典列表分类和分组为嵌套字典，我想通过API将其返回为JSON.

How can I sort and group this list of dictionaries into a nested dictionary which I want to return via an API as JSON.

源数据(权限列表):

[{ 'can_create': True, 'can_read': True, 'module_name': 'ModuleOne', 'module_id': 1, 'role_id': 1, 'end_point_id': 1, 'can_update': True, 'end_point_name': 'entity', 'can_delete': True, }, { 'can_create': True, 'can_read': True, 'module_name': 'ModuleTwo', 'module_id': 2, 'role_id': 1, 'end_point_id': 4, 'can_update': True, 'end_point_name': 'financial-outlay', 'can_delete': True, },{ 'can_create': True, 'can_read': True, 'module_name': 'ModuleOne', 'module_id': 1, 'role_id': 1, 'end_point_id': 2, 'can_update': True, 'end_point_name': 'management-type', 'can_delete': True, }, { 'can_create': True, 'can_read': True, 'module_name': 'ModuleOne', 'module_id': 1, 'role_id': 1, 'end_point_id': 3, 'can_update': True, 'end_point_name': 'ownership-type', 'can_delete': False, }, { 'can_create': True, 'can_read': True, 'module_name': 'ModuleTwo', 'module_id': 2, 'role_id': 1, 'end_point_id': 5, 'can_update': True, 'end_point_name': 'exposure', 'can_delete': True, }]

我想将其转换为嵌套的数字对象，以API作为JSON返回.这是预期的输出:

I want to transform that into a nested dicitonary object for return with an API as JSON. Here's the expected output:

{ "role_id": 1, "modules": [{ "module_id": 1, "module_name": "ModuleOne", "permissions": [{ "end_point_id": 1, "end_point_name": "entity", "can_create": False, "can_read": True, "can_write": True, "can_delete": True }, { "end_point_id": 2, "end_point_name": "management-type", "can_create": False, "can_read": True, "can_write": True, "can_delete": True }, { "end_point_id": 3, "end_point_name": "ownership-type", "can_create": False, "can_read": True, "can_write": True, "can_delete": True }, ] }, { "module_id": 2, "module_name": "ModuleTwo", "permissions": [{ "end_point_id": 4, "end_point_name": "financial-outlay", "can_create": False, "can_read": True, "can_write": True, "can_delete": True }, { "end_point_id": 5, "end_point_name": "exposure", "can_create": False, "can_read": True, "can_write": True, "can_delete": True }, ] }, ] }

在我花更多的时间来尝试改变主意之前，它看起来微不足道.我尝试了很多选择，但都不起作用.这是最后一次尝试.

It looked trivial until I spent more time that I would expect trying to bend my mind around it. I've attempted so many options with non of them working. Here's the last attempt.

# Get user role user_roles = get_user_roles() # List of roles e.g. [{'role_id':1, role_name: 'role_one'}, {'role_id':2, role_name: 'role_two'}] for role in user_roles: role_id = role['role_id'] role_name = role['role_name'] # Fetch Role Permissions role_permissions = get_role_permissions(role_id) # List of permissions as seen above sorted_role_permissions = sorted(role_permissions, key=itemgetter('module_id')) # sort dictionaries in list by 'module_id' modules_list = [] permissions_list = [] previous_module_id = 0 is_first_loop = True for role_permission in sorted_role_permissions: module_id = role_permission['module_id'] module_name = role_permission['module_name'] end_point_id = role_permission['end_point_id'] end_point_name = role_permission['end_point_name'] if is_first_loop: print(0) is_first_loop = False previous_module_id = module_id print('end_point_name 0 {}'.format(end_point_name)) permissions = {'end_point_id': end_point_id, 'end_point_name': end_point_name, 'can_create': role_permission['can_create'], 'can_read': role_permission['can_read'], 'can_update': role_permission['can_update'], 'can_delete': role_permission['can_delete'] } permissions_list.append(permissions) if len(sorted_role_permissions) == 1: # If there is only one permission in the role, end the loop modules_dict = {'module_id': module_id, 'module_name': module_name, 'permissions': permissions_list} modules_list.append(modules_dict) break else: if module_id == previous_module_id: # As long as the current module_id and the previous_module_id are the same, add to the same list print(1) permissions = {'end_point_id': end_point_id, 'end_point_name': end_point_name, 'can_create': role_permission['can_create'], 'can_read': role_permission['can_read'], 'can_update': role_permission['can_update'], 'can_delete': role_permission['can_delete'] } permissions_list.append(permissions) else: print(2) modules_dict = {'module_id': module_id, 'module_name': module_name, 'permissions': permissions_list} modules_list.append(modules_dict) permissions_list = [] permissions = {'end_point_id': end_point_id, 'end_point_name': end_point_name, 'can_create': role_permission['can_create'], 'can_read': role_permission['can_read'], 'can_update': role_permission['can_update'], 'can_delete': role_permission['can_delete'] } permissions_list.append(permissions) previous_module_id = module_id if modules_list: roles.append({'role_id': role_id, 'role_name': role_name, 'modules': modules_list})

推荐答案

TADA！

from itertools import groupby def group_by_remove(permissions, id_key, groups_key, name_key=None): """ @type permissions: C{list} of C{dict} of C{str} to C{object} @param id_key: A string that represents the name of the id key, like "role_id" or "module_id" @param groups_key: A string that represents the name of the key of the groups like "modules" or "permissions" @param name_key: A string that represents the name of the key of names like "module_name" (can also be None for no names' key) """ result = [] permissions_key = lambda permission: permission[id_key] # Must sort for groupby to work properly sorted_permissions = sorted(permissions, key=permissions_key) for key, groups in groupby(sorted_permissions, permissions_key): key_result = {} groups = list(groups) key_result[id_key] = key if name_key is not None: key_result[name_key] = groups[0][name_key] key_result[groups_key] = [{k: v for k, v in group.iteritems() if k != id_key and (name_key is None or k != name_key)} for group in groups] result.append(key_result) return result def change_format(initial): """ @type initial: C{list} @rtype: C{dict} of C{str} to C{list} of C{dict} of C{str} to C{object} """ roles_group = group_by_remove(initial, "role_id", "modules")[0] roles_group["modules"] = group_by_remove(roles_group["modules"], "module_id", "permissions", "module_name") return roles_group change_format(role_permissions)

享受:)