add annotator and code clean up

README.md

@@ -4,27 +4,82 @@ Toy scheduler for use in Kubernetes demos.
 
 ## Usage
 
+Annotate each node using the annotator command:
+
+```
+kubectl proxy
+```
+```
+Starting to serve on 127.0.0.1:8001
+```
+
+```
+go run annotator/main.go
+```
+```
+gke-k0-default-pool-728d327f-00lq 1.60
+gke-k0-default-pool-728d327f-3vzg 0.20
+gke-k0-default-pool-728d327f-nmz7 0.80
+gke-k0-default-pool-728d327f-pxee 0.05
+gke-k0-default-pool-728d327f-xm4i 0.05
+gke-k0-default-pool-728d327f-zynj 0.20
+```
+
+### Create a deployment
+
+```
+kubectl create -f deployments/nginx.yaml
+```
 ```
-kubectl get nodes
+deployment "nginx" created
+```
+
+The nginx pod should be in a pending state:
+
+```
+kubectl get pods
 ```
 ```
-NAME                                     STATUS    AGE
-gke-testing-default-pool-5b24138e-iw9u   Ready     14d
-gke-testing-default-pool-5b24138e-tudj   Ready     14d
-gke-testing-default-pool-5b24138e-vobb   Ready     14d
+NAME                     READY     STATUS    RESTARTS   AGE
+nginx-1431970305-mwghf   0/1       Pending   0          27s
 ```
 
+### Run the Scheduler
+
+List the nodes and note the price of each node.
+
+```
+annotator -l
 ```
-kubectl annotate nodes --overwrite \
-  gke-testing-default-pool-5b24138e-iw9u kubernetes.io/cost=0.05
 ```
+gke-k0-default-pool-728d327f-00lq 0.80
+gke-k0-default-pool-728d327f-3vzg 0.40
+gke-k0-default-pool-728d327f-nmz7 0.40
+gke-k0-default-pool-728d327f-pxee 0.05
+gke-k0-default-pool-728d327f-xm4i 1.60
+gke-k0-default-pool-728d327f-zynj 0.40
+```
+
+Run the best price scheduler:
 
 ```
-kubectl annotate nodes --overwrite \
-  gke-testing-default-pool-5b24138e-tudj kubernetes.io/cost=0.20
+scheduler
+```
+```
+2016/08/19 11:16:25 Starting custom scheduler...
+2016/08/19 11:16:28 Successfully assigned nginx-1431970305-mwghf to gke-k0-default-pool-728d327f-pxee
+2016/08/19 11:16:35 Shutdown signal received, exiting...
+2016/08/19 11:16:35 Stopped reconciliation loop.
+2016/08/19 11:16:35 Stopped scheduler.
 ```
 
+> Notice the pending nginx pod is deployed to the node with the lowest cost.
+
+## Run the Scheduler on Kubernetes
+
+```
+kubectl create -f deployments/scheduler.yaml
 ```
-kubectl annotate nodes --overwrite \
-  gke-testing-default-pool-5b24138e-vobb kubernetes.io/cost=1.60
+``` 
+deployment "scheduler" created
 ```

annotator/main.go

@@ -0,0 +1,101 @@
+package main
+
+import (
+	"bytes"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"math/rand"
+	"net/http"
+	"os"
+	"time"
+)
+
+var listOnly bool
+
+type NodeList struct {
+	Items []Node `json:"items"`
+}
+
+type Node struct {
+	Metadata Metadata `json:"metadata"`
+}
+
+type Metadata struct {
+	Name        string            `json:"name,omitempty"`
+	Annotations map[string]string `json:"annotations"`
+}
+
+func main() {
+	flag.BoolVar(&listOnly, "l", false, "List current annotations and exist")
+	flag.Parse()
+
+	prices := []string{"0.05", "0.10", "0.20", "0.40", "0.80", "1.60"}
+	resp, err := http.Get("http://127.0.0.1:8001/api/v1/nodes")
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	if resp.StatusCode != 200 {
+		fmt.Println("Invalid status code", resp.Status)
+		os.Exit(1)
+	}
+
+	var nodes NodeList
+	decoder := json.NewDecoder(resp.Body)
+	err = decoder.Decode(&nodes)
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+
+	if listOnly {
+		for _, node := range nodes.Items {
+			price := node.Metadata.Annotations["hightower.com/cost"]
+			fmt.Printf("%s %s\n", node.Metadata.Name, price)
+		}
+		os.Exit(0)
+	}
+
+	rand.Seed(time.Now().Unix())
+	for _, node := range nodes.Items {
+		price := prices[rand.Intn(len(prices))]
+		annotations := map[string]string{
+			"hightower.com/cost": price,
+		}
+		patch := Node{
+			Metadata{
+				Annotations: annotations,
+			},
+		}
+
+		var b []byte
+		body := bytes.NewBuffer(b)
+		err := json.NewEncoder(body).Encode(patch)
+		if err != nil {
+			fmt.Println(err)
+			os.Exit(1)
+		}
+
+		url := "http://127.0.0.1:8001/api/v1/nodes/" + node.Metadata.Name
+		request, err := http.NewRequest("PATCH", url, body)
+		if err != nil {
+			fmt.Println(err)
+			os.Exit(1)
+		}
+		request.Header.Set("Content-Type", "application/strategic-merge-patch+json")
+		request.Header.Set("Accept", "application/json, */*")
+
+		resp, err := http.DefaultClient.Do(request)
+		if err != nil {
+			fmt.Println(err)
+			os.Exit(1)
+		}
+
+		if resp.StatusCode != 200 {
+			fmt.Println(err)
+			os.Exit(1)
+		}
+		fmt.Printf("%s %s\n", node.Metadata.Name, price)
+	}
+}

bestprice.go

@@ -13,7 +13,9 @@
 
 package main
 
-import "strconv"
+import (
+	"strconv"
+)
 
 func bestPrice(nodes []Node) (Node, error) {
 	type NodePrice struct {

build-container

@@ -1,4 +1,4 @@
 GOOS=linux bash build
-docker build -t kelseyhightower/scheduler:0.2.0 .
-docker push kelseyhightower/scheduler:0.2.0
+docker build -t kelseyhightower/scheduler:0.4.0 .
+docker push kelseyhightower/scheduler:0.4.0
 rm scheduler

deployments/nginx.yaml

@@ -16,8 +16,8 @@ spec:
     spec:
       containers:
         - name: nginx
-          image: "nginx:1.11"
+          image: "nginx:1.11.1-alpine"
           resources:
             requests:
-              cpu: "200m"
-              memory: "64M"
+              cpu: "500m"
+              memory: "128M"

deployments/scheduler.yaml

@@ -14,7 +14,7 @@ spec:
     spec:
       containers:
         - name: scheduler
-          image: kelseyhightower/scheduler:0.2.0
+          image: kelseyhightower/scheduler:0.4.0
         - name: kubectl
           image: kelseyhightower/kubectl:1.3.4
           args: