FIWARE Policy Manager - User and Programmers Guide¶
Introduction¶
Welcome the User and Programmer Guide for the Policy Manager Generic Enabler. The online documents are being continuously updated and improved, and so will be the most appropriate place to get the most up to date information on using this interface.
Background and Detail¶
This User and Programmers Guide relates to the Policy Manager GE which is part of the Cloud Hosting Chapter. Please find more information about this Generic Enabler in the following Open Specification.
User Guide¶
The Policy Manager GE is a backend component, without user interface. Therefore there is no need to provide a user guide. The Cloud Portal can be used for Web-based interaction (but it is not part of this GE).
Programmer Guide¶
Policy Manager API is based upon HTTP and therefore all devices, which can handle HTTP traffic, are possible clients.
Accessing Policy Manager from the CLI¶
To invoke the REST API use the curl program. Curl 1 is a client to get documents/files from or send documents to a server, using any of the supported protocols (HTTP, HTTPS, FTP, GOPHER, DICT, TELNET, LDAP or FILE) and therefore is also usable for Policy Manager API. Use the curl command line tool or use libcurl from within your own programs in C. Curl is free and open software that compiles and runs under a wide variety of operating systems.
In order to make a probe of the different functionalities related to the Policy Manager, we make a list of several operations to make a probe of the execution of these GEis.
1. Get a valid token for the tenant that we have (It is not a Policy Manager operation but a IdM operation).
Due to all operations of the Policy Manager are using the security mechanism which is used in the rest of the cloud component, it is needed to provide a security token in order to continue with the rest of operations.
curl -d '{"auth": {"tenantName": $TENANT, "passwordCredentials":{"username": $USERNAME,
"password": $PASSWORD}}}' -H "Content-type: application/json"
-H "Accept: application/xml" http://130.206.80.100:35357/v2.0/tokens
Both $TENANT (Project), $USERNAME and $PASSWORD must be values previously created in the OpenStack Keystone. The IP address 10.95.171.115 and the Port 35357 are the data of our internal installation of IdM, if you planned to execute it you must changed it by the corresponding IP and Port of the FIWARE Keystone or IdM IP and Port addresses.
We obtained two data from the previous sentence:
- X-Auth-Token
<token expires="2012-10-25T16:35:42Z" id="a9a861db6276414094bc1567f664084d">
- Tenant-Id
<tenant enabled="true" id="c907498615b7456a9513500fe24101e0" name=$TENANT>
2. Get tenant information
This is the first real operation about our GEi, by which we can obtain the information about the Policy Manager, together with the information about the window size fixed for the execution of the GEi. For more information about the window size and its meaning.
curl -v -H 'X-Auth-Token: a9a861db6276414094bc1567f664084d'
-X GET http://130.206.81.71:8000/v1.0/c907498615b7456a9513500fe24101e0
This operation will return the information regarding the tenant details of the execution of the Policy Manager
< HTTP/1.0 200 OK
< Date: Wed, 09 Apr 2014 08:25:17 GMT
< Server: WSGIServer/0.1 Python/2.6.6
< Content-Type: text/html; charset=utf-8
{
"owner": "Telefonica I+D",
"doc": "https://forge.fi-ware.org/plugins/mediawiki/wiki/fi-ware-private/index.php/
FIWARE.OpenSpecification.Details.Cloud.PolicyManager",
"runningfrom": "14/04/09 07:45:22",
"version": 1.0,
"windowsize": 5
}
3. Create a rule for a server
This operation allows to create a specific rule associate to a server:
curl -v -H 'X-Auth-Token: 86e096cd4de5490296fd647e21b7f0b4'
-X POST http://130.206.81.71:8000/v1.0/6571e3422ad84f7d828ce2f30373b3d4/servers
/32c23ac4-230d-42b6-81f2-db9bd7e5b790/rules/
-d '{"action": {"actionName": "notify-scale", "operation": "scaleUp"}, "name": "ScaleUpRule",
"condition": { "cpu": { "value": 98, "operand": "greater" },
"mem": { "value": 95, "operand": "greater equal"}}}'
The result of this operation is the following content:
< HTTP/1.0 200 OK
< Date: Wed, 09 Apr 2014 10:14:11 GMT
< Server: WSGIServer/0.1 Python/2.6.6
< Content-Type: text/html; charset=utf-8
{
"serverId": "32c23ac4-230d-42b6-81f2-db9bd7e5b790",
"ruleId": "68edb416-bfc6-11e3-a8b9-fa163e202949"
}
4. Subscribe the server to the rule
Through this operation we can subscribe a rule to be monitored in order to evaluate the rule to be processed.
curl -v -H 'X-Auth-Token: a9a861db6276414094bc1567f664084d'
-X POST http://130.206.81.71:8000/v1.0/6571e3422ad84f7d828ce2f30373b3d4/servers
/32c23ac4-230d-42b6-81f2-db9bd7e5b790/subscription
-d '{ "ruleId": "ruleid", "url": "URL to notify any action" }'
An the expected result is the following.
< HTTP/1.0 200 OK
< Date: Wed, 09 Apr 2014 10:16:11 GMT
< Server: WSGIServer/0.1 Python/2.6.6
< Content-Type: text/html; charset=utf-8
{
"serverId": "32c23ac4-230d-42b6-81f2-db9bd7e5b790",
"subscriptionId": "6f231936-bfce-11e3-9a13-fa163e202949"
}
5. Manual simulation of data transmission to the server
This operation simulate the operation that the context broker used to send data to the Policy Manager, the normal execution of this process will be automatically once that the Policy Manager subscribes a rule to a specific server. The operation is related to fiware-facts component and it has the following appearance:
curl -v -H "Content-Type: application/json"
-X POST http://127.0.0.1:5000/v1.0/6571e3422ad84f7d828ce2f30373b3d4/servers/serverI1
-d '{
"contextResponses": [
{
"contextElement": {
"attributes": [
{
"value": "0.12",
"name": "usedMemPct",
"type": "string"
},
{
"value": "0.14",
"name": "cpuLoadPct",
"type": "string"
},
{
"value": "0.856240",
"name": "freeSpacePct",
"type": "string"
},
{
"value": "0.8122",
"name": "netLoadPct",
"type": "string"
}
],
"id": "Trento:193.205.211.69",
"isPattern": "false",
"type": "host"
},
"statusCode": {
"code": "200",
"reasonPhrase": "OK"
}
}]
}'
Which produces the following result after the execution:
* About to connect() to 127.0.0.1 port 5000 (#0)
* Trying 127.0.0.1...
* Adding handle: conn: 0x7fa2e2804000
* Adding handle: send: 0
* Adding handle: recv: 0
* Curl_addHandleToPipeline: length: 1
* - Conn 0 (0x7fa2e2804000) send_pipe: 1, recv_pipe: 0
* Connected to 127.0.0.1 (127.0.0.1) port 5000 (#0)
> POST /v1.0/33/servers/44 HTTP/1.1
> User-Agent: curl/7.30.0
> Host: 127.0.0.1:5000
> Accept: */*
> Content-Type: application/json
> Content-Length: 1110
> Expect: 100-continue
>
< HTTP/1.1 100 Continue
< HTTP/1.1 200 OK
< Content-Type: text/html; charset=utf-8
< Content-Length: 0
< Date: Wed, 09 Apr 2014 00:11:49 GMT
<
* Connection #0 to host 127.0.0.1 left intact
6. Unsubscribe the previous rule
In order to stop the process to evaluate rules, it is needed to unsubscribe the activated rule. We can do it with the following operation:
curl -v -H 'X-Auth-Token: a9a861db6276414094bc1567f664084d'
-X DELETE http://130.206.81.71:8000/v1.0/6571e3422ad84f7d828ce2f30373b3d4/servers
/serverI1/subscription/SubscriptionId
< HTTP/1.0 200 OK
< Date: Wed, 09 Apr 2014 10:16:59 GMT
< Server: WSGIServer/0.1 Python/2.6.6
< Content-Type: text/html; charset=utf-8