Commerce License Billing

Commerce License Billing provides advanced (prepaid, postpaid, prorated, plan-based, metered) recurring billing for licenses.

Dependencies: Bundleswitcher, Commerce License, Advanced queue.

Getting started

1. Go to admin/config/licenses/billing-cycle-types and add a billing cycle type.
2. Create a product, select a license type, then below select your billing cycle type and billing type (prepaid or postpaid).
3. Checkout the product. If you selected postpaid as the billing type, your product will be free.
4. A billing cycle has now been opened (with the current start date, and the end date depending on your billing cycle type settings), along with a matching recurring order.
5. When the billing cycle expires, the recurring order will be closed and charged for using Commerce Card on File, and a new billing cycle & order will be opened.

Relationship to Commerce License

Any license type can be used for recurring billing without changes. A license is considered billable if its product has a billing cycle type selected.

If the license type wants to have metered billing, it must implement the CommerceLicenseBillingUsageInterface interface.

By default, licenses are revisionable, but changes to a license don't create new revisions. Commerce License Billing changes that logic for billable licenses, ensuring that a new revision is created for status or product_id changes (this is essential for later pricing and prorating).

Prepaid billing

Prepaid products are paid up front.

That means that if a customer registers on April 1st, he will immediately pay the monthly fee for April. On the first day of May, he will be charged for the april usage (if any), and the monthly fee for May. If on May 15h he cancels his subscription, on the first day of June he will only pay the usage for May.

The other half of the May monthly fee will not be refunded, since that is not currently implemented (a common strategy being to award the customer points to be used for discounting future purchases).

Postpaid billing

Postpaid products are paid at the end of the billing cycle.

That means that if the customer registers on April 1st, his order is free and he pays nothing. On the first day of May, he will be charged for the April monthly fee, and the april usage (if any). If on May 15th he cancels his subscription, on the first day of June he will pay the prorated montly fee for May, and the usage for May.

Prorated payments

A prorated payment is a payment proportional to the duration of the usage. So, if the billing cycle is two weeks, but the plan was used for one week, only half of the plan's price will be set on the line item.

The usage records have start and end timestamps. Plans are priced by examining license revisions, each of which has a revision_created and revision_ended timestamp, used the same way.

If the end timestamp is 0, it is assumed that the record is still active / in progress, so the end of the billing cycle is taken as the end instead, in order to give a cost estimation. The duration (end - start) is compared to the billing cycle duration, and the record is priced proportionally.

Plan-based billing

Each license has one plan at a given point of time, which is the referenced product.

Licenses are revisionable, and Commerce License Billing modifies the default behavior so that new revisions are always created for product_id (plan) and status changes. Each revision has a revision_created and revision_ended timestamp. The revision_ended timestamp is 0 for the current revision. The timestamps are used to prorate the price of each plan that was active during the billing cycle.

Only revisions with status COMMERCE_LICENSE_ACTIVE are priced, so if a license was suspended for a week, that period won't be priced since that revision will be ignored.

Metered (usage-based) billing

If a license type implements the CommerceLicenseBillingUsageInterface interface and declares its usage groups, the module will allow usage to be registered and calculated for each usage group separately, and charge for it at the end of the billing cycle.

Usage is reported asynchronously, and it is your job to call commerce_license_billing_usage_group($license, $group_name)->addUsage() and register usage (after an API call received through Services, or after contacting the service yourself on cron, etc). If a license has usage groups, the billing cycle won't be closed until all usage has been reported for each plan (start - end pairs cover each plan duration in the billing cycle).

There are two types of usage groups: counter and gauge.

• The counter tracks usage over time, and is always charged for in total. For example if the following bandwidth usage was reported: Jan 1st - Jan 15th; 1024 and Jan 15th - Jan 31st; 128, there will be one line item, charging for 1052mb of usage.

• The gauge tracks discrete usage values over time, and each value is charged for separately. For example, if the following env usage is reported Jan 1st - Jan 15th; 2 and Jan 15th - Jan 31st; 4, there will be two prorated line items, charging for 2 and 4 environments. The gauge type also allows for open-ended usage (immediate => TRUE), in which case it is carried over into the next billing cycles.

Note that the gauge usage is prorated, and the counter usage isn't.

A usage group can also define free_quantity, the quantity provided for free with the license. Only usage exceeding this quantity will be charged for. For counters this means that the free quantity is subtracted from the total quantity. For gauges this means that the gauge values that equal free_quantity are ignored.

The free_quantity value can be hardcoded, or taken from the license's product (making it plan-based, which is a common use case, with Plan A providing one quantity for free, and Plan B providing another quantity for free). The module makes sure to price the usage according to the plan that was active at the time.

See:

• CommerceLicenseBillingUsageInterface
• CommerceLicenseBillingUsageGroupInterface
• CommerceLicenseBillingCounterUsageGroup
• CommerceLicenseBillingGaugeUsageGroup
• commerce_license_billing_usage_group()
• commerce_license_billing_usage_history_list()
• commerce_license_billing_usage_clear()

Recurring order refresh

The recurring order is refreshed each time it is loaded (hook_commerce_order_load()), updating the line items (quantities, prices) based on the latest plan history and usage.

The start and end timestamps on the line items are maintained. For counter usage, they match the start and end of the billing cycle, since counter usage is not prorated. For gauge usage and plans, it reflects the exact period that is used for prorating.

Billing cycle types

Billing cycle types are exportable entities managed on admin/config/licenses/billing-cycle-types. Each billing cycle type has a bundle, the billing cycle engine, powered by entity bundle plugin. This allows each billing cycle type to have methods for creating and naming new billing cycles. See CommerceLicenseBillingCycleEngineInterface and CommerceLicenseBillingCycleTypeBase for more information.

The module provides a "periodic" billing cycle engine that generates periodic billing cycles (daily/weekly/monthly, synchronous or asynchronous).

Fields and bundles

The module creates the following fields on any product type that's license enabled:

• cl_billing_cycle_type - Reference to the billing cycle type.
• cl_billing_type - The billing type (prepaid / postpaid).

It provides the recurring line item type with the following additional fields:

• cl_billing_start - a datetime field, used for prorating.
• cl_billing_end - a datetime field, used for prorating.
• cl_billing_license - Reference to the license for which the line item was generated.

It provides the recurring order type with the following additional fields:

• cl_billing_cycle - Reference to the billing cycle.