From 35954cd5b13ef6359cf6b304feb49d81771e06ee Mon Sep 17 00:00:00 2001
From: Imtiaz Uddin <imtiaz@appscode.com>
Date: Fri, 29 Sep 2023 15:08:11 +0600
Subject: [PATCH] Add quota decision in resource calculator create api

Signed-off-by: Imtiaz Uddin <imtiaz@appscode.com>
---
 .../meta/resourcecalculator/storage.go        | 121 +++++++++++++++++-
 1 file changed, 119 insertions(+), 2 deletions(-)

diff --git a/pkg/registry/meta/resourcecalculator/storage.go b/pkg/registry/meta/resourcecalculator/storage.go
index ba58de8c2..0be5290f9 100644
--- a/pkg/registry/meta/resourcecalculator/storage.go
+++ b/pkg/registry/meta/resourcecalculator/storage.go
@@ -18,7 +18,10 @@ package resourceCalculator
 
 import (
 	"context"
+	"fmt"
+	"strings"
 
+	core "k8s.io/api/core/v1"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
@@ -28,6 +31,8 @@ import (
 	"k8s.io/apiserver/pkg/authorization/authorizer"
 	"k8s.io/apiserver/pkg/registry/rest"
 	kmapi "kmodules.xyz/client-go/api/v1"
+	"kmodules.xyz/client-go/cluster"
+	"kmodules.xyz/resource-metadata/apis/management/v1alpha1"
 	rsapi "kmodules.xyz/resource-metadata/apis/meta/v1alpha1"
 	resourcemetrics "kmodules.xyz/resource-metrics"
 	"kmodules.xyz/resource-metrics/api"
@@ -96,8 +101,9 @@ func (r *Storage) Create(ctx context.Context, obj runtime.Object, createValidati
 		return nil, apierrors.NewInternalError(err)
 	}
 	rid := kmapi.NewResourceID(mapping)
+	pq := getProjectQuota(r.kc, u)
 
-	resp, err := ToGenericResource(&u, rid)
+	resp, err := ToGenericResource(&u, rid, pq)
 	if err != nil {
 		return nil, apierrors.NewInternalError(err)
 	}
@@ -110,7 +116,7 @@ func (r *Storage) ConvertToTable(ctx context.Context, object runtime.Object, tab
 	return r.convertor.ConvertToTable(ctx, object, tableOptions)
 }
 
-func ToGenericResource(item *unstructured.Unstructured, apiType *kmapi.ResourceID) (*rsapi.ResourceCalculatorResponse, error) {
+func ToGenericResource(item *unstructured.Unstructured, apiType *kmapi.ResourceID, pq *v1alpha1.ProjectQuota) (*rsapi.ResourceCalculatorResponse, error) {
 	content := item.UnstructuredContent()
 
 	var genres rsapi.ResourceCalculatorResponse
@@ -184,6 +190,117 @@ func ToGenericResource(item *unstructured.Unstructured, apiType *kmapi.ResourceI
 			}
 			genres.RoleResourceLimits = rv
 		}
+		{
+			rv, err := quota(content, pq, apiType)
+			if err != nil {
+				return nil, err
+			}
+			genres.Quota = *rv
+		}
 	}
 	return &genres, nil
 }
+
+func quota(obj map[string]interface{}, pq *v1alpha1.ProjectQuota, apiType *kmapi.ResourceID) (*rsapi.QuotaDecision, error) {
+	qd := &rsapi.QuotaDecision{
+		Decision:   rsapi.DecisionAllow,
+		Violations: make([]string, 0),
+	}
+	if pq == nil {
+		qd.Decision = rsapi.DecisionNoOpinion
+		return qd, nil
+	}
+	c, err := api.Load(obj)
+	if err != nil {
+		return nil, err
+	}
+
+	requests, err := c.AppResourceRequests(obj)
+	if err != nil {
+		return nil, err
+	}
+	limits, err := c.AppResourceLimits(obj)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, quota := range pq.Status.Quotas {
+		if quota.Group == apiType.Group {
+			if quota.Kind != "" && quota.Kind != apiType.Kind {
+				continue
+			}
+			hardRequests, hardLimits := extractRequestsLimits(quota.Hard)
+			usedRequests, usedLimits := extractRequestsLimits(quota.Used)
+
+			totRequestsUsage := api.AddResourceList(requests, usedRequests)
+			for rn, usageQuan := range totRequestsUsage {
+				hr, found := hardRequests[rn]
+				if !found {
+					continue
+				}
+				if usageQuan.Cmp(hr) > 0 {
+					r := requests[rn]
+					u := usedRequests[rn]
+					l := hardRequests[rn]
+
+					qd.Decision = rsapi.DecisionDeny
+					qd.Violations = append(qd.Violations,
+						fmt.Sprintf("Project quota exceeded. Requested: requests.%s=%s, Used: requests.%s=%s, Limited: requests.%s=%s", rn, r.String(), rn, u.String(), rn, l.String()))
+				}
+			}
+
+			totLimitsUsage := api.AddResourceList(limits, usedLimits)
+			for rn, usageQuan := range totLimitsUsage {
+				hl, found := hardLimits[rn]
+				if !found {
+					continue
+				}
+				if usageQuan.Cmp(hl) > 0 {
+					r := limits[rn]
+					u := usedLimits[rn]
+					l := hardLimits[rn]
+
+					qd.Decision = rsapi.DecisionDeny
+					qd.Violations = append(qd.Violations,
+						fmt.Sprintf("Project quota exceeded. Requested: limits.%s=%s, Used: limits.%s=%s, Limited: limits.%s=%s", rn, r.String(), rn, u.String(), rn, l.String()))
+				}
+			}
+		}
+	}
+
+	return qd, nil
+}
+
+func extractRequestsLimits(res core.ResourceList) (core.ResourceList, core.ResourceList) {
+	requests := core.ResourceList{}
+	limits := core.ResourceList{}
+
+	for fullName, quan := range res {
+		identifier, name, found := strings.Cut(fullName.String(), ".")
+		if !found {
+			continue
+		}
+
+		if identifier == "requests" {
+			requests[core.ResourceName(name)] = quan
+		} else {
+			limits[core.ResourceName(name)] = quan
+		}
+	}
+
+	return requests, limits
+}
+
+func getProjectQuota(kc client.Client, u unstructured.Unstructured) *v1alpha1.ProjectQuota {
+	projectId, _, err := cluster.GetProjectId(kc, u.GetNamespace())
+	if err != nil {
+		return nil
+	}
+	var pj v1alpha1.ProjectQuota
+	err = kc.Get(context.TODO(), client.ObjectKey{Name: projectId}, &pj)
+	if err != nil {
+		return nil
+	}
+
+	return &pj
+}