bzp2010 commented on a change in pull request #5970: URL: https://github.com/apache/apisix/pull/5970#discussion_r779261322
########## File path: docs/en/latest/plugins/opa.md ########## @@ -0,0 +1,275 @@ +--- +title: opa +--- + +<!-- +# +# 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. +# +--> + +## Summary + +- [**Description**](#description) +- [**Attributes**](#attributes) +- [**Data Definition**](#data-definition) +- [**Example**](#example) + +## Description + +The `opa` plugin is used to integrate with Open Policy Agent. By using this plugin, users can decouple functions such as authentication and access to services and reduce the complexity of the application system. + +## Attributes + +| Name | Type | Requirement | Default | Valid | Description | +| -- | -- | -- | -- | -- | -- | +| host | string | required | | | Open Policy Agent service host (eg. https://localhost:8181) | +| ssl_verify | boolean | optional | true | | Whether to verify the certificate | +| policy | string | required | | | OPA policy path (It is a combination of `package` and `decision`. When you need to use advanced features such as custom response, `decision` can be omitted) | +| timeout | integer | optional | 60000ms | [1, 60000]ms | HTTP call timeout. | +| keepalive | boolean | optional | true | | HTTP keepalive | +| keepalive_timeout | integer | optional | 60000ms | [1000,...] | keepalive idle timeout | +| keepalive_pool | integer | optional | 5 | [1,...] | Connection pool limit | +| with_route | boolean | optional | false | | Whether to send information about the current route. | +| with_service | boolean | optional | false | | Whether to send information about the current service. | +| with_consumer | boolean | optional | false | | Whether to send information about the current consumer. (It may contain sensitive information such as apikey, so please turn it on only if you are sure it is safe) | + +## Data Definition + +### APISIX to OPA service + +The `type` indicates that the request type. (e.g. `http` or `stream`) +The `reqesut` is used when the request type is `http`, it contains the basic information of the request. (e.g. url, header) +The `var` contains basic information about this requested connection. (e.g. IP, port, request timestamp) +The `route`, `service`, and `consumer` will be sent only after the `opa` plugin has enabled the relevant features, and their contents are same as those stored by APISIX in etcd. + +```json +{ + "type": "http", + "request": { + "scheme": "http", + "path": "\/get", + "headers": { + "user-agent": "curl\/7.68.0", + "accept": "*\/*", + "host": "127.0.0.1:9080" + }, + "query": {}, + "port": 9080, + "method": "GET", + "host": "127.0.0.1" + }, + "var": { + "timestamp": 1701234567, + "server_addr": "127.0.0.1", + "server_port": "9080", + "remote_port": "port", + "remote_addr": "ip address" + }, + "route": {}, + "service": {}, + "consumer": {} +} +``` + +### OPA service response to APISIX + +In the response, `result` is automatically added by OPA. The `allow` is indispensable and will indicate whether the request is allowed to be forwarded through the APISIX. +The reason, headers, and status_code are optional and are only returned when you need to use a custom response, as you'll see in the next section with the actual use case for it. + +```json +{ + "result": { + "allow": true, + "reason": "test", + "headers": { + "an": "header" + }, + "status_code": 401 + } +} +``` + +## Example + +First, you need to run the Open Policy Agent environment. + +```shell +docker run -d --name opa -p 8181:8181 openpolicyagent/opa:0.35.0 run -s +``` + +### Basic Use Case + +You can create a basic policy for testing. + +```shell +curl -XPUT '127.0.0.1:8181/v1/policies/example1' \ +--header 'Content-Type: text/plain' \ +--data-raw 'package example1 + +import input.request + +default allow = false + +allow { + # HTTP method must GET + request.method == "GET" +}' +``` + +After that, you can create a route and turn on the `opa` plugin. + +```shell +curl -XPUT 'http://127.0.0.1:9080/apisix/admin/routes/r1' \ +--header 'X-API-KEY: <api-key>' \ +--header 'Content-Type: application/json' \ +--data-raw '{ + "uri": "/*", + "plugins": { + "opa": { + "host": "http://127.0.0.1:8181";, + "policy": "example1" + } + }, + "upstream": { + "nodes": { + "httpbin.org:80": 1 + }, + "type": "roundrobin" + } +}' +``` + +Try it out. + +```shell +# Successful request +curl -i -XGET 127.0.0.1:9080/get +HTTP/1.1 200 OK + +# Failed request +curl -i -XPOST 127.0.0.1:9080/post +HTTP/1.1 403 FORBIDDEN +``` + +### Complex Use Case (custom response) + +Next, let's think about some more complex scenarios. + +When you need to return a custom error message for an incorrect request, you can implement it this way. + +```shell +curl -XPUT '127.0.0.1:8181/v1/policies/example2' \ +--header 'Content-Type: text/plain' \ +--data-raw 'package example2 + +import input.request + +default allow = false + +allow { + request.method == "GET" +} + +# custom response body (Accepts a string or an object, the object will respond as JSON format) +reason = "test" { + not allow +} + +# custom response header (The data of the object can be written in this way) +headers = { + "Location": "http://example.com/auth"; +} { + not allow +} + +# custom response status code +status_code = 302 { + not allow +}' +``` + +Update the route and set `opa` plugin's `policy` parameter to `example2`. Then, let's try it. + +```shell +# Successful request +curl -i -XGET 127.0.0.1:9080/get +HTTP/1.1 200 OK + +# Failed request +curl -i -XPOST 127.0.0.1:9080/post +HTTP/1.1 302 FOUND +Location: http://example.com/auth + +test +``` + +### Complex Use Case (send APISIX data) + +Let's think about another scenario, when your decision needs to use some APISIX data, such as `route`, `consumer`, etc., how should we do it? + +Create a simple policy `echo`, which will return the data sent by APISIX to the OPA service as is, so we can simply see them. + +```shell +curl -XPUT '127.0.0.1:8181/v1/policies/echo' \ +--header 'Content-Type: text/plain' \ +--data-raw 'package echo + +allow = false +reason = input' +``` + +Next, update the config of the route to enable sending route data. + +```shell +curl -XPUT 'http://127.0.0.1:9080/apisix/admin/routes/r1' \ +--header 'X-API-KEY: <api-key>' \ +--header 'Content-Type: application/json' \ +--data-raw '{ + "uri": "/*", + "plugins": { + "opa": { + "host": "http://127.0.0.1:8181";, + "policy": "echo", + "with_route": true + } + }, + "upstream": { + "nodes": { + "httpbin.org:80": 1 + }, + "type": "roundrobin" + } +}' +``` + +Try it. As you can see, we output this data with the help of the custom response body function described above, along with the data from the route. + +```shell +curl -XGET 127.0.0.1:9080/get Review comment: added -- 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: notifications-unsubscr...@apisix.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
