# Hashmap rating module¶

CloudKitty is shipped with core rating modules.

## Hashmap composition¶

You can see hashmap as a simple tree:

HashMap is composed of different resources and groups.

### Group¶

A group is a way to group calculations of mappings. For example you might want to apply a set of rules to charge instance_uptime and another set to block storage volume. You don’t want the two to be linked so you’ll create one group for each calculation.

### Service¶

A service is a way to map the rule to the type of data collected (compute, image, volume).

### Field¶

A field is referring to a metadata field of a resource. For example on an instance object (compute), you can use the flavor to define specific rules.

### Mapping¶

A mapping is the final object, it’s what triggers calculation, for example a specific value of flavor on an instance. It maps cost to a value of metadata in case of field mapping. And directly a cost in case of service mapping.

### Threshold¶

A threshold entry is used to apply rating rules base on level. Its behaviour is similar to a mapping except that it applies the cost base on the level.

## HashMap formula¶

Based on all the previous objects here’s the calculation formula : $$\sum_{n=1}^N G_n(qty.(T_{rate}\prod(M_{rate})(T_{flat}+M_{flat})))$$

G: Group Quantity of resource threshold threshold

## Example¶

### Compute uptime¶

Apply rating rule on the compute service to charge the instance based on it’s flavor and uptime:

Create a group instance_uptime_flavor:

$cloudkitty hashmap-create-group -n instance_uptime_flavor$ cloudkitty hashmap-group-list
+------------------------+--------------------------------------+
| Name                   | Group id                             |
+------------------------+--------------------------------------+
+------------------------+--------------------------------------+


Create the service matching rule:

$cloudkitty hashmap-service-create -n compute +------------+--------------------------------------+ | Property | Value | +------------+--------------------------------------+ | name | compute | | service_id | 08ab2d27-fe95-400c-9602-e5ad5efdda8b | +------------+--------------------------------------+  Create a field matching rule: $ cloudkitty hashmap-field-create \
+------------+--------------------------------------+
| Property   | Value                                |
+------------+--------------------------------------+
| field_id   | f37364af-6525-40fc-ae08-6d4087429862 |
| name       | flavor                               |
| service_id | None                                 |
+------------+--------------------------------------+


Create a mapping in the group instance_uptime_flavor that will map m1.tiny instance to a cost of 0.01:

$cloudkitty hashmap-mapping-create \ -f f37364af-6525-40fc-ae08-6d4087429862 \ -v m1.tiny -t flat -c 0.01 -g 26d2d69a-4c42-47f1-9d44-2cdfad167f7d +------------+--------------------------------------+ | Property | Value | +------------+--------------------------------------+ | cost | 0.01 | | field_id | f37364af-6525-40fc-ae08-6d4087429862 | | group_id | 26d2d69a-4c42-47f1-9d44-2cdfad167f7d | | mapping_id | df592a91-a6a5-41fa-ba2e-2f763eaa36e5 | | service_id | None | | type | flat | | value | m1.tiny | +------------+--------------------------------------+  In this example every machine with the flavor m1.tiny will be charge 0.01 per collection period. ### Volume per gb with discount¶ Now let’s do some threshold based rating. Create a group volume_thresholds: $ cloudkitty hashmap-create-group -n volume_thresholds
$cloudkitty hashmap-group-list +-------------------+--------------------------------------+ | Name | Group id | +-------------------+--------------------------------------+ | volume_thresholds | dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d | +-------------------+--------------------------------------+  Create the service matching rule: $ cloudkitty hashmap-service-create -n volume
+------------+--------------------------------------+
| Property   | Value                                |
+------------+--------------------------------------+
| name       | volume                               |
| service_id | 16a48060-0e64-11e6-8e4e-1b285514a36e |
+------------+--------------------------------------+


Now let’s setup the price per gigabyte:

$cloudkitty hashmap-mapping-create \ -s 16a48060-0e64-11e6-8e4e-1b285514a36e \ -t flat -c 0.001 -g dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d +------------+--------------------------------------+ | Property | Value | +------------+--------------------------------------+ | cost | 0.001 | | field_id | None | | group_id | dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d | | mapping_id | 41669786-240b-11e6-872c-af96ddb6619c | | service_id | 16a48060-0e64-11e6-8e4e-1b285514a36e | | type | flat | | value | None | +------------+--------------------------------------+  We have the basic price per gigabyte be we now want to apply a discount on huge data volumes. Create the thresholds in the group volume_thresholds that will map different volume quantity to costs: Here we set a threshold when going past 50GB, and apply a 2% discount (0.98): $ cloudkitty hashmap-threshold-create \
-s 16a48060-0e64-11e6-8e4e-1b285514a36e \
-l 50 -t rate -c 0.98 -g dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d
+------------+--------------------------------------+
| Property   | Value                                |
+------------+--------------------------------------+
| cost       | 0.98                                 |
| field_id   | None                                 |
| group_id   | dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d |
| level      | 50                                   |
| service_id | 16a48060-0e64-11e6-8e4e-1b285514a36e |
| type       | rate                                 |
+------------+--------------------------------------+


Here we set a threshold when going past 200GB, and apply a 5% discount (0.95):

\$ cloudkitty hashmap-threshold-create \
-s 16a48060-0e64-11e6-8e4e-1b285514a36e \
-l 200 -t rate -c 0.95 -g dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d
+------------+--------------------------------------+
| Property   | Value                                |
+------------+--------------------------------------+
| cost       | 0.95                                 |
| field_id   | None                                 |
| group_id   | dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d |
| level      | 200                                  |
| mapping_id | baf180c8-0e64-11e6-abb3-cbae153a6d44 |
| service_id | 16a48060-0e64-11e6-8e4e-1b285514a36e |
| type       | rate                                 |
+------------+--------------------------------------+


In this example every volume is charged 0.01 per GB but if the size goes past 50GB you’ll get a 2% discount, if you even go further you’ll get 5% discount (only one level apply at a time).

20GB: 0.02 per collection period. 0.049 per collection period. 0.0784 per collection period. 0.2375 per collection period.