rushitote commented on a change in pull request #4710: URL: https://github.com/apache/apisix/pull/4710#discussion_r680961580
########## File path: apisix/plugins/authz-casbin.lua ########## @@ -0,0 +1,118 @@ +-- +-- Licensed to the Apache Software Foundation (ASF) under one or more +-- contributor license agreements. See the NOTICE file distributed with +-- this work for additional information regarding copyright ownership. +-- The ASF licenses this file to You under the Apache License, Version 2.0 +-- (the "License"); you may not use this file except in compliance with +-- the License. You may obtain a copy of the License at +-- +-- http://www.apache.org/licenses/LICENSE-2.0 +-- +-- Unless required by applicable law or agreed to in writing, software +-- distributed under the License is distributed on an "AS IS" BASIS, +-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +-- See the License for the specific language governing permissions and +-- limitations under the License. +-- + +local casbin = require("casbin") +local core = require("apisix.core") +local plugin = require("apisix.plugin") +local ngx = ngx +local get_headers = ngx.req.get_headers +local lrucache = core.lrucache.new({ + ttl = 300, count = 32 +}) + +local plugin_name = "authz-casbin" + +local schema = { + type = "object", + properties = { + model_path = { type = "string" }, + policy_path = { type = "string" }, + username = { type = "string"} + }, + required = {"model_path", "policy_path", "username"}, + additionalProperties = false +} + +local metadata_schema = { + type = "object", + properties = { + model = {type = "string"}, + policy = {type = "string"}, + }, + required = {"model", "policy"}, + additionalProperties = false +} + +local _M = { + version = 0.1, + priority = 2560, + name = plugin_name, + schema = schema, + metadata_schema = metadata_schema +} + +function _M.check_schema(conf, schema_type) + if schema_type == core.schema.TYPE_METADATA then + return core.schema.check(metadata_schema, conf) + end + local ok, err = core.schema.check(schema, conf) + if ok then + return true + else + local metadata = plugin.plugin_metadata(plugin_name) + if metadata and metadata.value and conf.username then + return true + end + end + return false, err +end + + +local function new_enforcer(conf, modifiedIndex) + local model_path = conf.model_path + local policy_path = conf.policy_path + + local e + + if model_path and policy_path then + e = casbin:new(model_path, policy_path) + conf.type = "file" + end + + local metadata = plugin.plugin_metadata(plugin_name) + if metadata and metadata.value.model and metadata.value.policy and not e then + local model = metadata.value.model + local policy = metadata.value.policy + e = casbin:newEnforcerFromText(model, policy) + conf.type = "metadata" Review comment: @spacewander I was thinking of something like this: ```lua local casbin_enforcer local function new_enforcer(conf, modifiedIndex) local model_path = conf.model_path local policy_path = conf.policy_path if model_path and policy_path then conf.type = "file" conf.casbin_enforcer = casbin:new(model_path, policy_path) return end local metadata = plugin.plugin_metadata(plugin_name) if metadata and metadata.value.model and metadata.value.policy then conf.type = "metadata" if not casbin_enforcer or casbin_enforcer.modifiedIndex ~= modifiedIndex then local model = metadata.value.model local policy = metadata.value.policy casbin_enforcer = casbin:newEnforcerFromText(model, policy) casbin_enforcer.modifiedIndex = modifiedIndex end end end function _M.rewrite(conf, ctx) -- creates an enforcer when request sent for the first time local metadata = plugin.plugin_metadata(plugin_name) if (not conf.casbin_enforcer and conf.type ~= "metadata") or (conf.type == "metadata" and casbin_enforcer.modifiedIndex ~= metadata.modifiedIndex) then new_enforcer(conf, metadata.modifiedIndex) end local path = ctx.var.uri local method = ctx.var.method local username = get_headers()[conf.username] if not username then username = "anonymous" end if conf.casbin_enforcer then if not conf.casbin_enforcer:enforce(username, path, method) then return 403, {message = "Access Denied"} end else if not casbin_enforcer:enforce(username, path, method) then return 403, {message = "Access Denied"} end end end ``` So, we divide routes into two types - either `file` or `metadata`. The `file` one has their own enforcer binded to the conf while all the `metadata` based routes use the same `casbin_enforcer`. In case of the metadata based route, enforcer is created only when either there isn't one or when the `modifiedIndex` has changed. And since this separates any route into one of the two types, one type will not override the other. Will this solve the issue? -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
