如何用curl 来访问MESOS Scheduler HTTP API

MESOS 提供了Scheduler HTTP RESTful API. 不论是软件开发人员还是软件测试人员都可以通过这些API 进一步了解mesos的工作机制。本文讲述了如何用curl来访问这些API。

环境配置

1.mesos master，master的command options 设置如下：

MESOS_MASTER_OPTS="--work_dir=/var/lib/mesos --log_dir=/var/log/mesos"

2 mesos slaves，每个slave的配置是一样的，2 CPU，996M memory。slave的command options设置如下

MESOS_SLAVE_OPTS="--master=$MESOS_MASTER_IP:5050 --log_dir=/var/log/mesos"

注册Framework

1.注册framework是framework与mesos master通信的第一步。Framework注册成功之后，才会建立起和mesos master之间的联系。运行以下命令来注册一个framework。

# curl –vv --no-buffer –X POST -H "Content-Type: application/json" -d@register.json http://$MESOS_MASTER_IP:5050/master/api/v1/scheduler

curl 后面的-d 指的是传送给API的data. 这个data是个json串。在命令行中写长的json串是个比较痛苦的事情，最好将json串写进一个文件。本例中该文件的名字为register.json. json文件怎么定义可以查看 mesos.proto ， scheduler.proto .

Response body like this: * upload completely sent off: 257 out of 257 bytes < HTTP/1.1 200 OK < Date: Fri, 15 Apr 2016 05:56:03 GMT < Mesos-Stream-Id: b3a3e239-f0ad-43d3-b635-1c1d9c66566b < Content-Type: application/json < X-Cache: MISS from db03b04 < X-Cache-Lookup: MISS from db03b04:3128 < Transfer-Encoding: chunked < Via: 1.1 db03b04 (squid/3.3.8) < Connection: keep-alive < 70 {"subscribed":{"framework_id":{"value":"test13"}},"type":"SUBSCRIBED"}20 {"offers":{"offers":[{"agent_id":{"value":"b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-S1"},"framework_id":{"value":"test13"},"hostname":"slave1","id":{"value":"b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-O4"},"resources":[{"name":"cpus","role":"*","scalar":{"value":2.0},"type":"SCALAR"},{"name":"mem","role":"*","scalar":{"value":996.0},"type":"SCALAR"},{"name":"disk","role":"*","scalar":{"value":30509.0},"type":"SCALAR"},{"name":"ports","ranges":{"range":[{"begin":31000,"end":32000}]},"role":"*","type":"RANGES"}],"url":{"address":{"hostname":"slave1","ip":"9.111.254.36","port":5051},"path":"//slave(1)","scheme":"http"}},{"agent_id":{"value":"b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-S0"},"framework_id":{"value":"test13"},"hostname":"slave0","id":{"value":"b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-O5"},"resources":[{"name":"cpus","role":"*","scalar":{"value":2.0},"type":"SCALAR"},{"name":"mem","role":"*","scalar":{"value":996.0},"type":"SCALAR"},{"name":"disk","role":"*","scalar":{"value":30509.0},"type":"SCALAR"},{"name":"ports","ranges":{"range":[{"begin":31000,"end":32000}]},"role":"*","type":"RANGES"}],"url":{"address":{"hostname":"slave0","ip":"9.111.254.62","port":5051},"path":"//slave(1)","scheme":"http"}}]},"type":"OFFERS"}

Mesos-Stream-Id, 作为该framework的唯一标识。在后面的actions 像launch task， decline offers等都需要用到它.framework 注册成功之后，如果master 有资源的话，该framework会收到master发送来的offers。

register.json文件内容示例：

{ "framework_id": {"value" : "test13"}, "type":"SUBSCRIBE", "subscribe":{ "framework_info":{ "user":"root", "name":"test13", "failover_timeout":60, "role":"aa", "id":{"value":"test13"}, "principal":"test", "capabilities":{"type":"REVOCABLE_RESOURCES"} }, "force":true } }

2.使用已注册好的framework 来launch task。

# curl -vv --no-buffer -X POST -H "Content-Type: application/json" -H "Mesos-Stream-Id:b3a3e239-f0ad-43d3-b635-1c1d9c66566b" -d@launch_task.json http://$MESOS_MASTER_IP:5050/master/api/v1/scheduler

Response body like this:

* Done waiting for 100-continue < HTTP/1.1 202 Accepted < Date: Wed, 13 Apr 2016 05:37:44 GMT < Content-Length: 0 < X-Cache: MISS from db03b04 < X-Cache-Lookup: MISS from db03b04:3128 < Via: 1.1 db03b04 (squid/3.3.8) < Connection: keep-alive

launch_task.json文件内容示例：

{         "framework_id":{"value":"test13"},         "type":"ACCEPT",         "accept":{                 "offer_ids":[                         {"value":"81c111bd-f27d-41a4-b184-64090dec3048-O428"}                         ],                 "filters":{},                 "operations":[                                 {                                 "type":"LAUNCH",                                 "launch":{"task_infos":[{                                                         "name":"task 00012",                                                         "task_id":{"value": "00012"},                                                         "agent_id":{"value": "5bb4aba0-628b-4309-b36f-767db1ebb7f4-S0"},                                                         "resources":[                                                                         {                                                                         "name":"mem",                                                                         "type":"SCALAR",                                                                         "scalar":{"value":996.0}                                                                         },                                                                         {                                                                         "name":"cpus",                                                                         "type":"SCALAR",                                                                         "scalar":{"value":1.0}                                                                         }                                                                 ],                                                         "command":{"value": "/bin/sleep 3000s"}                                                         }                                                         ]                                                 }                                         }                         ]         } }

Result

查看framework output ， framework 收到了UPDATE event， 这是MESOS master发给framework更新task 状态的UPDATE

{"type":"UPDATE","update":{"status":{"agent_id":{"value":"b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-S1"},"container_status":{"network_infos":[{"ip_address":"9.111.254.36","ip_addresses":[{"ip_address":"9.111.254.36"}]}]},"executor_id":{"value":"00016"},"source":"SOURCE_EXECUTOR","state":"TASK_RUNNING","task_id":{"value":"00016"},"timestamp":1460526113.05411,"uuid":"H9KoCldtRTu0T7halLxs9w=="}}}20 {"type":"HEARTBEAT"}391 

# curl -vv --no-buffer -X POST -H "Content-Type: application/json" -H "Mesos-Stream-Id:b3a3e239-f0ad-43d3-b635-1c1d9c66566b" -d@acknowledge.json http://$MESOS_MASTER_IP:5050/master/api/v1/scheduler

Response body like this:

* upload completely sent off: 264 out of 264 bytes < HTTP/1.1 202 Accepted < Date: Wed, 13 Apr 2016 06:01:31 GMT < Content-Length: 0 < X-Cache: MISS from db03b04 < X-Cache-Lookup: MISS from db03b04:3128 < Via: 1.1 db03b04 (squid/3.3.8) < Connection: keep-alive

acknowledge.json的文件内容示例如下：

{   "framework_id"    : {"value" : "test13"},   "type"            : "ACKNOWLEDGE",   "acknowledge"     : {     "agent_id"  :  {"value" : "b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-S1"},     "task_id"   :  {"value" : "00016"},     "uuid"      :  "H9KoCldtRTu0T7halLxs9w=="   } }

Result

在Framework的output里，同样UUID的event信息不再出现

4.当task 运行完毕的时候，它所占用的资源会被释放掉，从而一个新的资源产生了，master又将该资源按照DRF算法发给了相应的framework。

5.Decline offer, 如果目前分配给framework的offer不合适，framework可以decline it。

# curl -vv --no-buffer -X POST -H "Content-Type: application/json" -H "Mesos-Stream-Id:b3a3e239-f0ad-43d3-b635-1c1d9c66566b" -d@decline.json http://$MESOS_MASTER_IP:5050/master/api/v1/scheduler

Response body like this

* upload completely sent off: 214 out of 214 bytes < HTTP/1.1 202 Accepted < Date: Wed, 13 Apr 2016 06:17:56 GMT < Content-Length: 0 < X-Cache: MISS from db03b04 < X-Cache-Lookup: MISS from db03b04:3128 < Via: 1.1 db03b04 (squid/3.3.8) < Connection: keep-alive <

decline.json 文件内容示例：

{   "framework_id"    : {"value" : "test13"},   "type"            : "DECLINE",   "decline"         : {     "offer_ids" : [                    {"value" : "b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-O15"}                   ]   } }

Result

被decline的offer不再可用。

6.如果在mesos cluster 运行很多个task，在mesos cluster 系统里面就会不停的创造出很多的资源碎片，这些碎片都不能单独的launch task的时候，该怎么办呢？有两个办法可以合并同一个slave上面的资源碎片。

6.1 ACCEPT event

在launch task的时候，将slave上面的碎片资源写成list，这样会自动合并碎片资源。注意这些资源碎片一定是属于同一个slaveLaunch_task.json 文件内容示例：

{         "framework_id":{"value":"test13"},         "type":"ACCEPT",         "accept":{                 "offer_ids":[                  {"value":"b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-O14"}, {"value":"b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-O16"}                         ],                 "filters":{},                 "operations":[                                 {                                 "type":"LAUNCH",                                 "launch":{"task_infos":[{                                                         "name":"task 00017",                                                         "task_id":{"value": "00017"},                                                         "agent_id":{"value": "b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-S1"},                                                         "resources":[                                                                         {                                                                         "name":"mem",                                                                         "type":"SCALAR",                                                                         "scalar":{"value":996.0}                                                                         },                                                                         {                                                                         "name":"cpus",                                                                         "type":"SCALAR",                                                                         "scalar":{"value":2.0}                                                                         }                                                                 ],                                                         "command":{"value": "/bin/sleep 180s"}                                                         }                                                         ]                                                 }                                         }                         ]         } } 

当task运行完毕，mesos master就会将这些资源作为整块资源按照DRF算法发给相应的framework

6.2 decline event 合并碎片资源

将各个碎片资源decline掉， 这样也能整合碎片资源。 例如有三个offers，这3个offer都属于同一个slave。decline 这些offer之后，mesos master会自动整合这些碎片资源，然后按照DRF算法将合并后的资源发给相应的framework

{"offers":{"offers":[{"agent_id":{"value":"b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-S1"},"framework_id":{"value":"test13"},"hostname":"slave1","id":{"value":"b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-O24"},"resources":[{"name":"cpus","role":"*","scalar":{"value":1.0},"type":"SCALAR"},{"name":"mem","role":"*","scalar":{"value":512.0},"type":"SCALAR"}],"url":{"address":{"hostname":"slave1","ip":"9.111.254.36","port":5051},"path":"//slave(1)","scheme":"http"}}]},"type":"OFFERS"}  {"offers":{"offers":[{"agent_id":{"value":"b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-S1"},"framework_id":{"value":"test13"},"hostname":"slave1","id":{"value":"b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-O26"},"resources":[{"name":"cpus","role":"*","scalar":{"value":1.0},"type":"SCALAR"},{"name":"mem","role":"*","scalar":{"value":256.0},"type":"SCALAR"}],"url":{"address":{"hostname":"slave1","ip":"9.111.254.36","port":5051},"path":"//slave(1)","scheme":"http"}}]},"type":"OFFERS"}  {"offers":{"offers":[{"agent_id":{"value":"b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-S1"},"framework_id":{"value":"test13"},"hostname":"slave1","id":{"value":"b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-O27"},"resources":[{"name":"ports","ranges":{"range":[{"begin":31000,"end":32000}]},"role":"*","type":"RANGES"},{"name":"mem","role":"*","scalar":{"value":228.0},"type":"SCALAR"},{"name":"disk","role":"*","scalar":{"value":30509.0},"type":"SCALAR"}],"url":{"address":{"hostname":"slave1","ip":"9.111.254.36","port":5051},"path":"//slave(1)","scheme":"http"}}]},"type":"OFFERS"}

decline offer 内容如下：

 {   "framework_id"    : {"value" : "test13"},   "type"            : "DECLINE",   "decline"         : {     "offer_ids" : [                    {"value" : "b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-O24"},                    {"value" : "b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-O26"},                    {"value" : "b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-O27"}                   ]   } }

decline 成功以后，一个整合过的offer就会发送给相应的framework

7.kill task。

kill event主要用于kill special task，一次kill一个task

 # curl -vv --no-buffer -X POST -H "Content-Type: application/json" -H "Mesos-Stream-Id:b3a3e239-f0ad-43d3-b635-1c1d9c66566b" -d@kill_task.json http://$MESOS_MASTER_IP:5050/master/api/v1/scheduler

Response body like this

* upload completely sent off: 211 out of 211 bytes < HTTP/1.1 202 Accepted < Date: Fri, 15 Apr 2016 13:08:25 GMT < Content-Length: 0 < X-Cache: MISS from db03b04 < X-Cache-Lookup: MISS from db03b04:3128 < Via: 1.1 db03b04 (squid/3.3.8) < Connection: keep-alive

kill_task.json 文件内容示例：

{   "framework_id"    : {"value" : "test13"},   "type"            : "KILL",   "kill"            : {     "task_id"   :  {"value" : "00020"},     "agent_id"  :  {"value" : "b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-S1"}   } }

ResultThe output in framework like this:

{"type":"UPDATE","update":{"status":{"agent_id":{"value":"b5e0c23f-237e-4398-816f-ad1a4aa7d3f3-S0"},"container_status":{"network_infos":[{"ip_address":"9.111.254.62","ip_addresses":[{"ip_address":"9.111.254.62"}]}]},"executor_id":{"value":"00012"},"message":"Command terminated with signal Terminated","source":"SOURCE_EXECUTOR","state":"TASK_KILLED","task_id":{"value":"00012"},"timestamp":1460725705.73596,"uuid":"mKSkxCycRLKS8y4YA2HM4A=="}}} 

 # curl -vv --no-buffer -X POST -H "Content-Type: application/json" -H  "Mesos-Stream-Id: b3a3e239-f0ad-43d3-b635-1c1d9c66566b" -d@teardown.json http://9.111.254.199:5050/master/api/v1/scheduler

Response body like this

* upload completely sent off: 77 out of 77 bytes < HTTP/1.1 202 Accepted < Date: Fri, 15 Apr 2016 13:25:49 GMT < Content-Length: 0 < X-Cache: MISS from db03b04 < X-Cache-Lookup: MISS from db03b04:3128 < Via: 1.1 db03b04 (squid/3.3.8) < Connection: keep-alive

teardown.json 文件内容如下：

{   "framework_id"    : {"value" : "test13"},   "type"            : "TEARDOWN" }

Result注册framework的进程会自动退出。Framework 变成inactive

作者简介:高智芳，IBM软件测试工程师，主要从事云计算领域相关的工作，平时喜欢尝试新的测试技术和测试方法。乐于在测试中发现bug。