feat: support autoscaling based on instance's RPS metrics (#134)

.github/workflows/ci.yaml

@@ -7,17 +7,17 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
-    - uses: actions/setup-go@v2
+    - uses: actions/setup-go@v3
       with:
-        go-version: 1.18
+        go-version: "1.20"
     - run: make test
 
   lint:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/setup-go@v3
       with:
-        go-version: 1.18
+        go-version: "1.20"
     - uses: actions/checkout@v2
     - uses: golangci/golangci-lint-action@v3
       with:
@@ -40,9 +40,9 @@ jobs:
       - uses: azure/setup-helm@v1
         with:
           version: v3.7.0
-      - uses: actions/setup-go@v2
+      - uses: actions/setup-go@v3
         with:
-          go-version: 1.18
+          go-version: "1.20"
       - uses: actions/cache@v2
         with:
           path: |
@@ -195,9 +195,9 @@ jobs:
           }
         }
         EOF
-    - uses: actions/setup-go@v2
+    - uses: actions/setup-go@v3
       with:
-        go-version: 1.18
+        go-version: "1.20"
     - uses: goreleaser/goreleaser-action@v1
       with:
         version: latest

Dockerfile.api

@@ -1,10 +1,10 @@
-FROM golang:1.18-alpine3.15 AS builder
+FROM golang:1.20-alpine3.18 AS builder
 COPY . /go/src/github.com/tsuru/rpaas-operator
 WORKDIR /go/src/github.com/tsuru/rpaas-operator
 RUN apk add --update gcc git make musl-dev && \
     make build/api
 
-FROM alpine:3.15
+FROM alpine:3.18
 COPY --from=builder /go/src/github.com/tsuru/rpaas-operator/bin/api /bin/rpaas-api
 RUN apk update && \
     apk add --no-cache ca-certificates && \

Dockerfile.operator

@@ -1,10 +1,10 @@
-FROM golang:1.18-alpine3.15 AS builder
+FROM golang:1.20-alpine3.18 AS builder
 COPY . /go/src/github.com/tsuru/rpaas-operator
 WORKDIR /go/src/github.com/tsuru/rpaas-operator
 RUN apk add --update gcc git make musl-dev && \
     make build/manager
 
-FROM alpine:3.15
+FROM alpine:3.18
 COPY --from=builder /go/src/github.com/tsuru/rpaas-operator/bin/manager /bin/rpaas-operator
 RUN apk update && \
     apk add --no-cache ca-certificates && \

Dockerfile.purger

@@ -1,10 +1,10 @@
-FROM golang:1.18-alpine3.15 AS builder
+FROM golang:1.20-alpine3.18 AS builder
 COPY . /go/src/github.com/tsuru/rpaas-operator
 WORKDIR /go/src/github.com/tsuru/rpaas-operator
 RUN apk add --update gcc git make musl-dev && \
     make build/purger
 
-FROM alpine:3.15
+FROM alpine:3.18
 COPY --from=builder /go/src/github.com/tsuru/rpaas-operator/bin/purger /bin/rpaas-purger
 RUN apk update && \
     apk add --no-cache ca-certificates && \

api/v1alpha1/rpaasinstance_types.go

@@ -240,6 +240,10 @@ type RpaasInstanceAutoscaleSpec struct {
 	// int32(80) equals to 80%.
 	// +optional
 	TargetMemoryUtilizationPercentage *int32 `json:"targetMemoryUtilizationPercentage,omitempty"`
+	// TargetRequestsPerSecond is the target rate of HTTP requests (in a second)
+	// pods should keep before scaling up/down pods.
+	// +optional
+	TargetRequestsPerSecond *int32 `json:"targetRequestsPerSecond,omitempty"`
 }
 
 type TLSSessionResumption struct {

cmd/plugin/rpaasv2/cmd/autoscale.go

@@ -8,7 +8,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"strconv"
 
 	"github.com/olekukonko/tablewriter"
 	rpaasclient "github.com/tsuru/rpaas-operator/pkg/rpaas/client"
@@ -56,19 +55,24 @@ func NewCmdUpdateAutoscale() *cli.Command {
 				Required: true,
 			},
 			&cli.IntFlag{
-				Name:     "cpu",
-				Aliases:  []string{"cpu-utilization"},
-				Usage:    "the target average CPU utilization on all replicas (in percentage format, e.g. 80 equals to 80%)",
-				Required: false,
+				Name:        "cpu",
+				Aliases:     []string{"cpu-utilization"},
+				Usage:       "the target average CPU utilization on all replicas (in percentage format, e.g. 80 equals to 80%)",
+				DefaultText: "N/A",
 			},
 			&cli.IntFlag{
-				Name:     "memory",
-				Aliases:  []string{"memory-utilization"},
-				Usage:    "the target average memory utilization on all the replicas (in percentage format, e.g. 80 equals to 80%)",
-				Required: false,
+				Name:        "memory",
+				Aliases:     []string{"memory-utilization"},
+				Usage:       "the target average memory utilization on all the replicas (in percentage format, e.g. 80 equals to 80%)",
+				DefaultText: "N/A",
+			},
+			&cli.IntFlag{
+				Name:        "rps",
+				Aliases:     []string{"requests-per-second"},
+				Usage:       "the target average of HTTP requests per seconds between replicas (e.g. 100, means 100 req/s)",
+				DefaultText: "N/A",
 			},
 		},
-
 		Before: setupClient,
 		Action: runUpdateAutoscale,
 	}
@@ -99,6 +103,10 @@ func runUpdateAutoscale(c *cli.Context) error {
 		updateArgs.Memory = pointerToInt32(int32(c.Int("memory")))
 	}
 
+	if c.IsSet("rps") {
+		updateArgs.RPS = pointerToInt32(int32(c.Int("rps")))
+	}
+
 	err = client.UpdateAutoscale(c.Context, updateArgs)
 	if err != nil {
 		return err
@@ -221,36 +229,41 @@ func writeAutoscale(w io.Writer, autoscale *clientTypes.Autoscale) {
 		return
 	}
 	table := tablewriter.NewWriter(w)
-	table.SetHeader([]string{"Replicas", "Target Utilization"})
+	table.SetHeader([]string{"Replicas", "Target"})
 	table.SetAutoFormatHeaders(false)
 	table.SetHeaderAlignment(tablewriter.ALIGN_LEFT)
 	table.SetAutoWrapText(true)
 	table.SetRowLine(false)
-	var max, min, cpuPercentage, memPercentage string
 
+	max := "Max: N/A"
 	if autoscale.MaxReplicas != nil {
-		max = fmt.Sprintf("Max: %s", strconv.Itoa(int(*autoscale.MaxReplicas)))
-	} else {
-		max = "Max: N/A"
+		max = fmt.Sprintf("Max: %d", *autoscale.MaxReplicas)
 	}
+
+	min := "Min: N/A"
 	if autoscale.MinReplicas != nil {
-		min = fmt.Sprintf("Min: %s", strconv.Itoa(int(*autoscale.MinReplicas)))
-	} else {
-		min = "Min: N/A"
+		min = fmt.Sprintf("Min: %d", *autoscale.MinReplicas)
 	}
+
+	cpuPercentage := "CPU: N/A"
 	if autoscale.CPU != nil {
-		cpuPercentage = fmt.Sprintf("CPU: %s%%", strconv.Itoa(int(*autoscale.CPU)))
-	} else {
-		cpuPercentage = "CPU: N/A"
+		cpuPercentage = fmt.Sprintf("CPU: %d%%", *autoscale.CPU)
 	}
+
+	memPercentage := "Memory: N/A"
 	if autoscale.Memory != nil {
-		memPercentage = fmt.Sprintf("Memory: %s%%", strconv.Itoa(int(*autoscale.Memory)))
-	} else {
-		memPercentage = "Memory: N/A"
+		memPercentage = fmt.Sprintf("Memory: %d%%", *autoscale.Memory)
+	}
+
+	rps := "RPS: N/A"
+	if autoscale.RPS != nil {
+		rps = fmt.Sprintf("RPS: %d req/s", *autoscale.RPS)
 	}
+
 	data := [][]string{
 		{max, cpuPercentage},
 		{min, memPercentage},
+		{"", rps},
 	}
 	table.AppendBulk(data)
 	table.Render()

cmd/plugin/rpaasv2/cmd/autoscale_test.go

@@ -46,15 +46,17 @@ func TestGetAutoscale(t *testing.T) {
 						MinReplicas: int32Ptr(2),
 						CPU:         int32Ptr(50),
 						Memory:      int32Ptr(55),
+						RPS:         int32Ptr(100),
 					}, nil
 				},
 			},
-			expected: `+----------+--------------------+
-| Replicas | Target Utilization |
-+----------+--------------------+
-| Max: 5   | CPU: 50%           |
-| Min: 2   | Memory: 55%        |
-+----------+--------------------+
+			expected: `+----------+----------------+
+| Replicas | Target         |
++----------+----------------+
+| Max: 5   | CPU: 50%       |
+| Min: 2   | Memory: 55%    |
+|          | RPS: 100 req/s |
++----------+----------------+
 `,
 		},
 		{
@@ -68,10 +70,11 @@ func TestGetAutoscale(t *testing.T) {
 						MinReplicas: int32Ptr(2),
 						CPU:         int32Ptr(50),
 						Memory:      int32Ptr(55),
+						RPS:         int32Ptr(100),
 					}, nil
 				},
 			},
-			expected: "{\n\t\"minReplicas\": 2,\n\t\"maxReplicas\": 5,\n\t\"cpu\": 50,\n\t\"memory\": 55\n}\n",
+			expected: "{\n\t\"minReplicas\": 2,\n\t\"maxReplicas\": 5,\n\t\"cpu\": 50,\n\t\"memory\": 55,\n\t\"rps\": 100\n}\n",
 		},
 	}
 	for _, tt := range tests {

cmd/plugin/rpaasv2/cmd/info_test.go

@@ -121,6 +121,7 @@ func TestInfo(t *testing.T) {
 							MinReplicas: int32Ptr(2),
 							CPU:         int32Ptr(55),
 							Memory:      int32Ptr(77),
+							RPS:         int32Ptr(100),
 						},
 						Pods: []clientTypes.Pod{
 							{
@@ -391,12 +392,13 @@ Errors:
 +--------------------+------------------------------+----------------------------------------------+
 
 Autoscale:
-+----------+--------------------+
-| Replicas | Target Utilization |
-+----------+--------------------+
-| Max: 5   | CPU: 55%           |
-| Min: 2   | Memory: 77%        |
-+----------+--------------------+
++----------+----------------+
+| Replicas | Target         |
++----------+----------------+
+| Max: 5   | CPU: 55%       |
+| Min: 2   | Memory: 77%    |
+|          | RPS: 100 req/s |
++----------+----------------+
 
 ACLs:
 +----------------------+------+