Call rating

This application serves rate_req AMQP requests.

Rates are stored in a system-wide “ratedeck” database.

Each rate is a separate document:

{
    "_id": "f36cac061205f7a0f7fde6b4d3370bf9",
    "_rev": "1-1b67fb507c69c35200178a9b1e0e6cfc",
    "routes": [
        "^\\+1[0-9]+$"
    ],
    "weight": "1",
    "rate_name": "outbound_US_1",
    "pvt_type": "rate",
    "prefix": "1",
    "rate_cost": "1.27",
    "ratedeck_name": "ratedeck_1",
    "iso_country_code": "US",
    "description": "USA prefix 1",
    "direction": [
       "outbound"
    ],
    "rate_increment": "60",
    "rate_minimum": "60",
    "rate_nocharge_time": "0",
    "options": [
        "Opt1",
        "Opt2"
    ]
}

Schema for these rate documents is described in the rates reference doc.

System Configuration

Key	Description	Type	Default
`default_rate_cost`	Cost used when `rate_cost` is not defined in rate	`float`	`0.0`
`default_rate_increment`	Increment call duration when `rate_increment` is not defined in rate	`integer`	`60`
`default_rate_minimum`	Minimum call duration when `rate_minimum` is not defined in rate	`integer`	`60`
`default_rate_nocharge_time`	No charge time when `rate_nocharge_time` is not defined in rate	`integer`	`0`
`default_rate_surcharge`	Surcharge used when `rate_surcharge` is not defined in rate	`float`	`0.0`
`filter_list.[]`		`string`
`filter_list`	List additional filters (after prefix match)	`array(string)`	`["direction", "route_options", "routes", "caller_id_numbers"]`
`sort_by_weight`	Sort matched filters by `weight`(`true`) or by `rate_cost` (`false`)	`boolean`	`true`
`use_trie`	Use in-memory prefix dictionary for search rates	`boolean`	`false`

Using the Trie

Rate lookups, by default, will use the CouchDB view rates/lookup and a list of prefixes generated by the dialed number to find any matching rates in the database. This is generally “fast enough” for most purposes. However, if the cluster is doing a lot of rate lookups, it may make sense to preload the rate table into memory for fast lookups. For reference, the trie implementation was ~128x faster in testing.

Starting the ‘hon_trie’ process will result in increased memory usage (~115 bytes per prefix in the database) on the VMs running hotornot. It would be advisable, if you have large ratedecks, to run a VM with just hotornot running to ensure memory is allocated properly.

To enable the trie, update the system_config: sup kapps_config set_default hotornot use_trie true and restart any VMs running hotornot: sup kapps_controller restart_app hotornot

Enabling the Trie

Enable the trie by setting use_trie to true in the system_config/hotornot document:

sup kapps_config set_boolean hotornot use_trie true

Filters

filter_list option is used to define additional filters when matching rates.

direction

If direction filter defined in filter_list then “Direction” value from rate request compared with direction value in rates. Undefined value in rate means “match any direction”.

route_options

If route_options filter defined in filter_list then “Options”, “Outbound-Flags” and resource ID from rate request compared with options value in rates. Rate matched when all flags in “Options”, “Outbound-Flags” and resource ID exist in options list in rate. Empty or undefined options list in rate means “match any route options”.

routes

If routes filter defined in filter_list then “To-DID” from rate request compared with list of regexps in routes value of rates. Rate matched if any of regexps matched. Empty regexps list or undefined value in rate means “match nobody” and this rate will never be used.

caller_id_numbers

If caller_id_numbers filter defined in filter_list then “From-DID” from rate request compared with list of regexps in caller_id_numbers value of rates. Rate matched if any of regexps matched. Undefined regexps list value in rate means “match all”.

ratedeck_name

If ratedeck_name filter defined in filter_list then ratedeck assigned to account compared with ratedeck_name value of rates. Ratedeck name assigned to account via service plan. If rate request doesn’t have “Account-ID” or account doesn’t have ratedeck name in their service plan, then it match rates with undefined ratedeck_name value.

reseller

If the reseller filter is defined in filter_list, then the reseller’s account ID is compared with the account_id value of the rates. If rate request doesn’t have “Account-ID” then it matches rates with undefined account_id value.

version

If version filter defined in filter_list then rate_version from system_config/hotornot compared with rate_version value of rates.