New chargeback calculations

[lpichler]

https://bugzilla.redhat.com/show_bug.cgi?id=1349413

Changes taking into account averages and maximums per selected interval in report(monthly, weekly, daily).
In general for allocated metric is used maximum and for used metrics is used average.

[chargio]

This starts to look great!

[miq-bot]

<pr_mergeability_checker />This pull request is not mergeable. Please rebase and repush.

[lpichler]

@miq-bot remove_label wip

[lpichler]

@gtanzillo I move out multiplying of cost method because we don't need it calculate (because we are not using accuntable period) separately fixed and variable part.

[lpichler]

@gtanzillo PR updated.

[gtanzillo]

All the calculations look perfect 👍 except for the "Storage Allocated Cost" where it seems there was a bug in the original rate tiers code.

[gtanzillo]

@lpichler I found a bug in this calculation when I was trying to verify the value for "Storage allocated Cost". It was showing 0 when it should be $29,760.00 => (1.0 fixed cost * 40gb * 744 hours).

It's incorrect because there should be parens around hourly(fixed_rate) + hourly(variable_rate). I made this change locally and got the correct cost:

diff --git a/app/models/chargeback_rate_detail.rb b/app/models/chargeback_rate_detail.rb
index 651249a..f9ac46e 100644
--- a/app/models/chargeback_rate_detail.rb
+++ b/app/models/chargeback_rate_detail.rb
@@ -72,7 +72,7 @@ class ChargebackRateDetail < ApplicationRecord

     (fixed_rate, variable_rate) = find_rate(value)

-    hourly(fixed_rate) +  hourly(variable_rate) * value
+    (hourly(fixed_rate) + hourly(variable_rate)) * value
   end

   def hourly(rate)

It looks like this was introduced with the tiered rates feature.

Here are before and after shot of the report so that you have a frame of reference -
Before

After

[lpichler]

@gtanzillo Nice finding, but I need to confirm these calculation which was used for it:
There are used this calculations:

I guess that was used this rate for Storage Allocate Cost:
Fixed: $1
Variable: $0
Per Time: Hourly
Per Unit: GB

Report setttings: Monthly

I guess fixed part should not be depend on metric value (value of Storage Allocate):
Hourly rate for GB: $1 (we have it already in hours)
Hourly rate for B(bytes, it is unit in MetricRollup table):$1 / (1024)^3 = 9.313225746154785e-10

9.313225746154785e-10 * 744(hours in month) = 6.92903995513916e-07

and in report it was rounded to $0.

Can you confirm it please ?

[gtanzillo]

After working through this with @lpichler and confirming with @sergio-ocon, we came up with a slightly different change -

diff --git a/app/models/chargeback_rate_detail.rb b/app/models/chargeback_rate_detail.rb
index 651249a..0ebbd48 100644
--- a/app/models/chargeback_rate_detail.rb
+++ b/app/models/chargeback_rate_detail.rb
@@ -72,10 +72,10 @@ class ChargebackRateDetail < ApplicationRecord

     (fixed_rate, variable_rate) = find_rate(value)

-    hourly(fixed_rate) +  hourly(variable_rate) * value
+    hourly(fixed_rate, true) + (hourly(variable_rate) * value)
   end

-  def hourly(rate)
+  def hourly(rate, fixed=nil)
     hourly_rate = case per_time
                   when "hourly"  then rate
                   when "daily"   then rate / 24
@@ -85,7 +85,7 @@ class ChargebackRateDetail < ApplicationRecord
                   else raise "rate time unit of '#{per_time}' not supported"
                   end

-    rate_adjustment(hourly_rate)
+    fixed ? hourly_rate : rate_adjustment(hourly_rate)
   end

   # Scale the rate in the unit difine by user to the default unit of the metric

Fixed rates whether in a tier or in fixed compute or storage should not involve the value of any metric. The only exception a fixed rate is in a tier, the metric value is used to find the correct tier, but in the calculation of the fixed cost.

See this screen shot for reference.

[lpichler]

thanks @gtanzillo for finding it - I made change in separated commit
0b6e9d6

I did it in slightly different way to see that only hourly variable part is adjusted regard to default unit metric in MetricRollup table.

[gtanzillo]

@zeari @bazulay @simon3z - fyi, this is the PR with all the new calculations for rolling up metrics and costs.

[miq-bot]

Checked commits lpichler/manageiq@f3506b7~...bdaad80 with ruby 2.2.5, rubocop 0.37.2, and haml-lint 0.16.1
6 files checked, 1 offense detected

app/models/chargeback_rate_detail.rb

• ❗ - Line 73, Col 23 - Style/RedundantSelf - Redundant self detected.

[lpichler]

@miq-bot remove_label wip

[lpichler]

@gtanzillo I just corrected calculation of hourly rate, when rate is monthly. It doesn't reflect real count of days in month before.

[gtanzillo]

👍 This one is ready to go!

[lpichler]

there is a list PRs which need to be merged first

#11645 (already backported to euwe)
#11647 (not backported to euwe)
#11685 (not backported to euwe)

[chessbyte]

Euwe BZ: https://bugzilla.redhat.com/show_bug.cgi?id=1346047

[chessbyte]

Euwe Backport details:

$ git log -1
commit d1b8be27e9d2208967d52fdb2bcc2326fd0c53a6
Author: Gregg Tanzillo <gtanzill@redhat.com>
Date:   Wed Oct 19 17:37:49 2016 -0400

    Merge pull request #11648 from lpichler/new_chargeback_calculations

    New chargeback calculations
    (cherry picked from commit 63996cc5ca543e61d4083af7554701ee21082130)

    https://bugzilla.redhat.com/show_bug.cgi?id=1346047

[chessbyte]

Backported to Darga via #12093