IBM Cloud: How to access the API for billing and usage?

How can I retrieve usage and cost data for my IBM Cloud account using a REST API? I found that there are billing related commands and I can export some data as JSON. Is there an API or SDK I can use, ideally Python?

Here are some of the IBM Cloud billing commands I use:

ibmcloud billing resource-instances-usage --json

ibmcloud billing  account-usage --json

Are there equivalent APIs for that?

Solution

UPDATED: An API is now documented here: https://cloud.ibm.com/apidocs/metering-reporting

OLD:

I couldn't find a documented API but used the tracing to see how the above commands are executed. Using a valid access_token a program can call the metering host and obtain usage data for an account, resource group or all resource instances:

A GET on the following URL with an account ID and month as YYYY-MM returns a JSON object with all resource usage and related cost:

https://metering-reporting.ng.bluemix.net/v4/accounts/account_id/resource_instances/usage/?_limit=100&_names=true

I coded up a small Python script that dumps that data or prints it as CSV.

def processResourceInstanceUsage(account_id, billMonth):
    METERING_HOST="https://metering-reporting.ng.bluemix.net"
    USAGE_URL="/v4/accounts/"+account_id+"/resource_instances/usage/"+billMonth+"?_limit=100&_names=true"

    url=METERING_HOST+USAGE_URL
    headers = {
        "Authorization": "{}".format(iam_token),
        "Accept": "application/json",
        "Content-Type": "application/json"
    }
    response=requests.get(url, headers=headers)
    print ("\n\nResource instance usage for first 100 items")
    return response.json()