API gateway 之 kong 基本操作 （三）
一、演示环境准备
1、nginx配置
[root@nginx conf.d]# pwd
/etc/nginx/conf.d
[root@nginx conf.d]# ls
conf_bak kong_test.conf
[root@nginx conf.d]# cat kong_test.conf
server {
listen ;
server_name 192.168.1.128; access_log /root/access.log main; location / {
root /usr/share/nginx/html;
index index.html index.htm;
}
}
[root@nginx conf.d]# cd /usr/share/nginx/html/
[root@nginx html]# ls
.html 50x.html index.html
[root@nginx html]# mkdir test
[root@nginx html]# cd test
[root@nginx test]# echo "`hostname` , hello" > first.html
[root@nginx test]# cat first.html
nginx , hello
二、基本操作
1、添加 API
官网教程：https://getkong.org/docs/0.10.x/getting-started/adding-your-api/
提示：在查看官网文档时默认会定向到最新的说明文档，要留意下当前kong版本选择对应的文档。
[root@kong_server ~]# curl -i -X POST http://localhost:8001/apis/ -d "name=first_api" -d "uris=/first" -d "upstream_url=http://192.168.1.129/test/first.html"
HTTP/1.1 Created
Date: Thu, Apr :: GMT
Content-Type: application/json; charset=utf-
Transfer-Encoding: chunked
Connection: keep-alive
Access-Control-Allow-Origin: *
Server: kong/0.10. {"http_if_terminated":true,"id":"683c6d99-5766-4cdf-bd3f-5b6b1e3afe67","retries":,"preserve_host":false,"created_at":,"upstream_connect_timeout":,"upstream_url":"http:\/\/192.168.1.129\/test\/first.html","upstream_read_timeout":,"https_only":false,"upstream_send_timeout":,"strip_uri":true,"name":"first_api","uris":["\/first"]}
当然，此步骤也可以通过kong的桌面管理工具进行操作 或者 UI工具操作，安装步骤见 API gateway 之 kong 安装（二）
a、验证是否已生效
[root@kong_server ~]# curl -i -X GET http://192.168.1.128:8000/first
HTTP/1.1 OK
Date: Thu, Apr :: GMT
Content-Type: text/html; charset=UTF-
Content-Length:
Connection: keep-alive
Server: nginx/1.10.
Last-Modified: Sat, Jan :: GMT
ETag: "5a5976a5-e"
Accept-Ranges: bytes
X-Kong-Upstream-Latency:
X-Kong-Proxy-Latency:
Via: kong/0.10. nginx , hello
这样，就添加了一个API，并通过kong代理请求到后端的nginx服务器上了，此时kong就是一个反向代理服务器，由于kong是api gateway，它支持很多安全、验证、日志等插件功能，所以就可以在API上添加想要实现的功能对应的插件
2、启用插件（basic auth）
basic auth插件作用就是当访问某个API时，需要经过认证用户名密码通过后才能访问。
官网教程：https://getkong.org/plugins/basic-authentication/?_ga=2.77732445.853990414.1523077059-1213803929.1523077059
a、关联插件到需要认证的API上面
[root@kong_server ~]# curl -X POST http://localhost:8001/apis/first_api/plugins -d "name=basic-auth" -d "config.hide_credentials=true"
{"api_id":"683c6d99-5766-4cdf-bd3f-5b6b1e3afe67","id":"61a6ebe0-677c-406e-b93f-a1da9b617db4","created_at":,"enabled":true,"name":"basic-auth","config":{"hide_credentials":true,"anonymous":""}}
b、创建一个消费者(consumer)
注意：这里的consumer主要是指代表一种角色，它也可以是多个不同名字的consumer，假如这个API我允许通过哪些角色的consumer访问，其他一律不允许，比如，jason, tom, jack等消费者角色，kong通常设置某些认证且只允许某个消费者来认证访问，后面演示中还会用到。
[root@kong_server ~]# curl -i -X POST http://localhost:8001/consumers/ -d "username=Jason"
HTTP/1.1 Created
Date: Fri, Apr :: GMT
Content-Type: application/json; charset=utf-
Transfer-Encoding: chunked
Connection: keep-alive
Access-Control-Allow-Origin: *
Server: kong/0.10. {"username":"Jason","created_at":,"id":"63d186fd-aa5c-449c-99d7-1f0cb7437e47"}
c、创建一个用户信息，即basic auth认证需要用到的用户名/密码
[root@kong_server ~]# curl -X POST http://localhost:8001/consumers/Jason/basic-auth \
> --data "username=user1" \
> --data "password=password1"
{"password":"0efeedcbcf5fbca03dc602dcd57fb77ea5c0d237","consumer_id":"63d186fd-aa5c-449c-99d7-1f0cb7437e47","id":"d38e51e0-7aef-4383-b9cb-cd5ff0b8eda2","username":"user1","created_at":}
d、再次访问加入basic auth认证后的 API
[root@kong_server ~]# curl -i -X GET http://localhost:8000/first --header "Authorization: Basic dXNlcjE6cGFzc3dvcmQx"
HTTP/1.1 OK
Date: Fri, Apr :: GMT
Content-Type: text/html; charset=UTF-
Content-Length:
Connection: keep-alive
Server: nginx/1.10.
Last-Modified: Sat, Jan :: GMT
ETag: "5a5976a5-e"
Accept-Ranges: bytes
X-Kong-Upstream-Latency:
X-Kong-Proxy-Latency:
Via: kong/0.10. nginx , hello
这里要注意的是，dXNlcjE6cGFzc3dvcmQx 这个是对字符串 "user1:password1" 做base64编码后的结果，即 echo -n "user1:password1" | base64,如果输入错误编码后的值，kong会返回403 Forbidden
[root@kong_server ~]# curl -i -X GET http://localhost:8000/first --header "Authorization: Basic hahaha"
HTTP/1.1 Forbidden
Date: Fri, Apr :: GMT
Content-Type: application/json; charset=utf-
Transfer-Encoding: chunked
Connection: keep-alive
Server: kong/0.10. {"message":"Invalid authentication credentials"}
浏览器访问效果
创建了这个basic auth用户名、密码后，可以把这个插件应用到其他的API上面，可以通过这个用户名密码登录验证。
3、key-auth 插件认证
官网教程：https://getkong.org/plugins/key-authentication/?_ga=2.44833389.853990414.1523077059-1213803929.1523077059
a、关联插件至指定API
[root@kong_server ~]# curl -i -X POST \
> --url http://localhost:8001/apis/first_api/plugins/ \
> --data 'name=key-auth'
HTTP/1.1 Created
Date: Fri, Apr :: GMT
Content-Type: application/json; charset=utf-
Transfer-Encoding: chunked
Connection: keep-alive
Access-Control-Allow-Origin: *
Server: kong/0.10. {"api_id":"683c6d99-5766-4cdf-bd3f-5b6b1e3afe67","id":"51c396d9-6ae1-45fe-a760-bbb1735f77b6","created_at":,"enabled":true,"name":"key-auth","config":{"hide_credentials":false,"anonymous":"","key_names":["apikey"],"key_in_body":false}}
此时已经向first_api这个API应用了2个插件，为了不影响，把basic-auth插件取消掉
b、验证是否生效
[root@nginx html]# curl -i -X GET --url http://192.168.1.128:8000/first
HTTP/1.1 Unauthorized
Date: Fri, Apr :: GMT
Content-Type: application/json; charset=utf-
Transfer-Encoding: chunked
Connection: keep-alive
WWW-Authenticate: Key realm="kong"
Server: kong/0.10. {"message":"No API key found in request"}
c、自定义API key给consumer
[root@kong_server ~]# curl -i -X POST \
> --url http://localhost:8001/consumers/Jason/key-auth/ \
> --data 'key=test_api_key_jason'
HTTP/1.1 Created
Date: Fri, Apr :: GMT
Content-Type: application/json; charset=utf-
Transfer-Encoding: chunked
Connection: keep-alive
Access-Control-Allow-Origin: *
Server: kong/0.10. {"created_at":,"consumer_id":"63d186fd-aa5c-449c-99d7-1f0cb7437e47","key":"test_api_key_jason","id":"fae89fb9-9e9b-4c98-bf7d-b393a81c297b"}
d、通过刚刚创建的API key访问API
[root@nginx html]# curl -i -X GET --url http://192.168.1.128:8000/first --header "apikey: test_api_key_jason"
HTTP/1.1 OK
Date: Fri, Apr :: GMT
Content-Type: text/html; charset=UTF-
Content-Length:
Connection: keep-alive
Server: nginx/1.10.
Last-Modified: Sat, Jan :: GMT
ETag: "5a5976a5-e"
Accept-Ranges: bytes
X-Kong-Upstream-Latency:
X-Kong-Proxy-Latency:
Via: kong/0.10. nginx , hello
浏览器访问：
e、通过kong自定义生成apikey（推荐这种方式）
[root@kong_server ~]# curl -i -X POST --url http://localhost:8001/consumers/ --data "username=Tom"
HTTP/1.1 Created
Date: Fri, Apr :: GMT
Content-Type: application/json; charset=utf-
Transfer-Encoding: chunked
Connection: keep-alive
Access-Control-Allow-Origin: *
Server: kong/0.10. {"username":"Tom","created_at":,"id":"665658e9-f88b-48a0-81c1-594df3bdf456"}
[root@kong_server ~]# curl -i -X POST --url http://localhost:8001/consumers/Tom/key-auth/ -d ""
HTTP/1.1 Created
Date: Fri, Apr :: GMT
Content-Type: application/json; charset=utf-
Transfer-Encoding: chunked
Connection: keep-alive
Access-Control-Allow-Origin: *
Server: kong/0.10. {"created_at":,"consumer_id":"665658e9-f88b-48a0-81c1-594df3bdf456","key":"d4661517c9a0463ebabcba7187d2ee0b","id":"16755308-0f55-427e-9cc6-c0d8de0897d4"}
也可以查询某个consumer的API key
[root@kong_server ~]# curl -i -X GET --url http://localhost:8001/consumers/Tom/key-auth/
HTTP/1.1 OK
Date: Fri, Apr :: GMT
Content-Type: application/json; charset=utf-
Transfer-Encoding: chunked
Connection: keep-alive
Access-Control-Allow-Origin: *
Server: kong/0.10. {"data":[{"created_at":,"consumer_id":"665658e9-f88b-48a0-81c1-594df3bdf456","key":"d4661517c9a0463ebabcba7187d2ee0b","id":"16755308-0f55-427e-9cc6-c0d8de0897d4"}],"total":}
[root@kong_server ~]#
[root@kong_server ~]#
[root@kong_server ~]# curl -i -X GET --url http://localhost:8001/consumers/Jason/key-auth/
HTTP/1.1 OK
Date: Fri, Apr :: GMT
Content-Type: application/json; charset=utf-
Transfer-Encoding: chunked
Connection: keep-alive
Access-Control-Allow-Origin: *
Server: kong/0.10. {"data":[{"created_at":,"consumer_id":"63d186fd-aa5c-449c-99d7-1f0cb7437e47","key":"test_api_key_jason","id":"fae89fb9-9e9b-4c98-bf7d-b393a81c297b"}],"total":}
f、访问测试
[root@nginx html]# curl -i -X GET --url http://192.168.1.128:8000/first --header 'apikey: d4661517c9a0463ebabcba7187d2ee0b'
HTTP/1.1 OK
Date: Fri, Apr :: GMT
Content-Type: text/html; charset=UTF-
Content-Length:
Connection: keep-alive
Server: nginx/1.10.
Last-Modified: Sat, Jan :: GMT
ETag: "5a5976a5-e"
Accept-Ranges: bytes
X-Kong-Upstream-Latency:
X-Kong-Proxy-Latency:
Via: kong/0.10. nginx , hello
浏览器访问：
4、IP Restriction 插件
官网教程：https://getkong.org/plugins/ip-restriction/?_ga=2.44833389.853990414.1523077059-1213803929.1523077059
Linux nginx服务器IP：192.168.1.129
这里把192.168.1.129的IP加入黑名单进行测试
a、管理插件至指定API
[root@kong_server ~]# curl -i -X POST http://localhost:8001/apis/first_api/plugins \
> --data "name=ip-restriction" \
> --data "config.blacklist=192.168.1.129, 143.1.0.0/24"
HTTP/1.1 Created
Date: Fri, Apr :: GMT
Content-Type: application/json; charset=utf-
Transfer-Encoding: chunked
Connection: keep-alive
Access-Control-Allow-Origin: *
Server: kong/0.10. {"api_id":"683c6d99-5766-4cdf-bd3f-5b6b1e3afe67","id":"3bdc6ea8-0fca-41f3-b330-36b2ce71c9e2","created_at":,"enabled":true,"name":"ip-restriction","config":{"blacklist":["192.168.1.129","143.1.0.0\/24"]}}
b、验证是否生效
只启用ip restriction插件
[root@nginx html]# curl -i -X GET --url http://192.168.1.128:8000/first
HTTP/1.1 Forbidden
Date: Fri, Apr :: GMT
Content-Type: application/json; charset=utf-
Transfer-Encoding: chunked
Connection: keep-alive
Server: kong/0.10. {"message":"Your IP address is not allowed"}
5、Rate limiting 访问速率限制
官网教程：https://getkong.org/plugins/rate-limiting/?_ga=2.85736144.853990414.1523077059-1213803929.1523077059
a、关联至API
[root@kong_server ~]# curl -X POST http://localhost:8001/apis/first_api/plugins \
> --data "name=rate-limiting" \
> --data "config.second=2" \
> --data "config.hour=100"
{"api_id":"683c6d99-5766-4cdf-bd3f-5b6b1e3afe67","id":"4135a8bf-13b6-4f6f-b006-f5afe65ae6cc","created_at":,"enabled":true,"name":"rate-limiting","config":{"fault_tolerant":true,"limit_by":"consumer","policy":"cluster","redis_database":,"second":,"hour":,"redis_timeout":,"redis_port":}}
config.second=2 表示每秒超过2次请求first_api接口时，将会被限制，提示限制信息
config.hour=100 表示一个小时内超过100次后就会被限制访问，提示限制信息
提示：这里是可以指定只限制某个consumer，加上参数就可了 consumer_id=CONSUMER
b、效果测试
[root@nginx html]# for i in {..}; do curl -X GET --url http://192.168.1.128:8000/first ; done
nginx , hello
nginx , hello
{"message":"API rate limit exceeded"}
浏览器快速刷新效果：
6、acl 访问控制
In order to use this plugin, you need to properly have configured your Service or Route (or API) with anauthentication plugin so that the plugin can identify who is the client Consumer making the request.
要使用这个插件的话，我们必须先配置好认证插件，可以是basic-auth, key-auth, OAth 2.0，其实这个acl插件需要知道是那个consumer发起的请求，由于前面几个认证插件都需要关联consumer，acl需要借助认证插件。
a、应用插件至API
[root@kong_server ~]# curl -X POST http://localhost:8001/apis/first_api/plugins/ \
> --data "name=acl" \
> --data "config.blacklist=group1"
{"api_id":"683c6d99-5766-4cdf-bd3f-5b6b1e3afe67","id":"3cfc5701-78f5-48d6-a475-28ac09b2fb9a","created_at":,"enabled":true,"name":"acl","config":{"blacklist":["group1"]}}
b、关联consumer
前面我们已经添加了 Jason, Tom 两个consumer, 我们再添加Jerry, Bob两个，以便分为2个组，然后让acl控制一个组做黑名单或白名单
[root@kong_server ~]# curl -X POST http://localhost:8001/consumers/ -d "username=Jerry"
{"username":"Jerry","created_at":,"id":"98c8d417-1572-48fe-99ee-feab95cb788e"}
[root@kong_server ~]# curl -X POST http://localhost:8001/consumers/ -d "username=Bob"
{"username":"Bob","created_at":,"id":"40fb4329-482c-432c-8a1c-101a3ddae328"} [root@kong_server ~]# curl -X POST http://localhost:8001/consumers/Jerry/key-auth/ -d ""
{"created_at":,"consumer_id":"98c8d417-1572-48fe-99ee-feab95cb788e","key":"d0baf3a09b074a65a14b66057ddd2f07","id":"417fd160-0282-483a-bdbf-6e7e183d0ff9"}
[root@kong_server ~]# curl -X POST http://localhost:8001/consumers/Bob/key-auth/ -d ""
{"created_at":,"consumer_id":"40fb4329-482c-432c-8a1c-101a3ddae328","key":"4cea214e55024c4aba0aeb3e79472ebe","id":"940d1166-bb78-424e-bb2f-5b50b2751c63"} [root@kong_server ~]# curl -X POST http://localhost:8001/consumers/Jerry/acls/ -d "group=group1"
{"group":"group1","consumer_id":"98c8d417-1572-48fe-99ee-feab95cb788e","created_at":,"id":"5259a6c1-4ddc-402d-8572-2651d46555f4"}
[root@kong_server ~]# curl -X POST http://localhost:8001/consumers/Bob/acls/ -d "group=group1"
{"group":"group1","consumer_id":"40fb4329-482c-432c-8a1c-101a3ddae328","created_at":,"id":"be2191d4-ecae-4638-ab5a-dd26c16d6002"}
c、验证是否生效
注意：这个是需要开启一个认证插件的，不然会报错
[root@nginx html]# curl -X GET --url http://192.168.1.128:8000/first
{"message":"Cannot identify the consumer, add an authentication plugin to use the ACL plugin"} [root@nginx html]# curl -X GET --url http://192.168.1.128:8000/first -H "apikey: test_api_key_jason"
{"message":"Cannot identify the consumer, add an authentication plugin to use the ACL plugin"}
以key-auth插件作为认证插件，开启key-auth插件，再测试
[root@nginx html]# curl -X GET --url http://192.168.1.128:8000/first -H "apikey: d0baf3a09b074a65a14b66057ddd2f07" # Jerry apikey
{"message":"You cannot consume this service"}
[root@nginx html]# curl -X GET --url http://192.168.1.128:8000/first -H "apikey: 4cea214e55024c4aba0aeb3e79472ebe" # Bob apikey
{"message":"You cannot consume this service"}
[root@nginx html]# curl -X GET --url http://192.168.1.128:8000/first -H "apikey: test_api_key_jason" # Jason 自定义apikey(不在黑名单组)
nginx , hello
7、syslog 插件
把指定api的请求日志记录到syslog日志
a、关联syslog插件
我们直接通过桌面管理工具添加
b、验证，访问API时，tailf /var/log/message（kong服务器）
[root@nginx html]# curl -i -X GET --url http://192.168.1.128:8000/first
HTTP/1.1 OK
Date: Fri, Apr :: GMT
Content-Type: text/html; charset=UTF-
Content-Length:
Connection: keep-alive
Server: nginx/1.10.
Last-Modified: Sat, Jan :: GMT
ETag: "5a5976a5-e"
Accept-Ranges: bytes
X-Kong-Upstream-Latency:
X-Kong-Proxy-Latency:
Via: kong/0.10. nginx , hello
系统日志
Apr :: base kong[]: {"client_ip":"192.168.1.129","request":{"method":"GET","uri":"\/first","size":"","request_uri":"http:\/\/192.168.1.128:8000\/first","querystring":{},"headers":{"host":"192.168.1.128:8000","accept":"*\/*","user-agent":"curl\/7.19.7 (x86_64-redhat-linux-gnu) libcurl\/7.19.7 NSS\/3.27.1 zlib\/1.2.3 libidn\/1.18 libssh2\/1.4.2"}},"response":{"status":,"size":"","headers":{"server":"nginx\/1.10.2","content-type":"text\/html; charset=UTF-8","connection":"close","content-length":"","x-kong-proxy-latency":"","last-modified":"Sat, 13 Jan 2018 03:01:57 GMT","x-kong-upstream-latency":"","accept-ranges":"bytes","via":"kong\/0.10.4","etag":"\"5a5976a5-e\""}},"latencies":{"request":,"kong":,"proxy":},"started_at":,"tries":[{"ip":"192.168.1.129","port":}],"api":{"uris":["\/first"],"id":"683c6d99-5766-4cdf-bd3f-5b6b1e3afe67","upstream_read_timeout":,"preserve_host":false,"created_at":,"upstream_connect_timeout":,"upstream_url":"http:\/\/192.168.1.129\/test\/first.html","strip_uri":true,"https_only":false,"name":"first_api","http_if_terminated":true,"upstream_send_timeout":,"retries":}}
更多插件应用：https://konghq.com/plugins/
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