Added tests and readme for taint

Signed-off-by: Gianluca Arbezzano <gianarb92@gmail.com>

.goreleaser.yml

@@ -15,7 +15,6 @@ dockers:
     image_templates:
     - "gianarb/kube-aws-node-labeler:latest"
     - "gianarb/kube-aws-node-labeler:{{ .Tag }}"
-    - "gianarb/kube-aws-node-labeler:v{{ .Major }}"
     skip_push: false
     # Path to the Dockerfile (from the project root).
     dockerfile: Dockerfile

README.md

@@ -7,15 +7,27 @@ new node joins the cluster. If the node has the label
 tags from AWS. Specifically it looks for instance tags like:
 
 ```
-kubernetes/aws-labeler/label/<labelName>=<labelValue>
+kubernetes/aws-labeler/label/type=ci
 ```
 If the EC2 has this tag the Kubernetes node will have a label called
 
 ```
-awslabeler.com/type=frontend
+awslabeler.com/type=ci
 ```
 That you can use to schedule your pods.
 
+Other than labels it also support taints:
+
+AWS EC2 tags like:
+```
+kubernetes/aws-labeler/taint/type=ci:NoExecute
+```
+Will become:
+
+```
+awslabeler.com/type=ci:NoExecute
+```
+
 ## Build
 
 ```

cmd/aws-node-labeler/main_test.go

@@ -0,0 +1,116 @@
+package main
+
+import (
+	"testing"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/service/ec2"
+	v1 "k8s.io/api/core/v1"
+)
+
+func TestInstanceIDFromProviderID(t *testing.T) {
+	r, err := InstanceIDFromProviderID("aws:///us-east-1c/i-0393ac1bb853a1fb5")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if r != "i-0393ac1bb853a1fb5" {
+		t.Fatalf("expected i-0393ac1bb853a1fb5 got %s", r)
+	}
+}
+
+func TestEC2TagIsManagableByTheLabeler(t *testing.T) {
+	cases := []struct {
+		input  string
+		output bool
+	}{
+		{"hello", false},
+		{"kubernetes/aws-labeler/label/type", true},
+		{"kubernetes/aws-labeler/tail/type", true},
+	}
+
+	for _, v := range cases {
+		t.Run("Input: "+v.input, func(t *testing.T) {
+			if isManagable(v.input) != v.output {
+				t.Errorf("different expectation for the instance tag %s", v.input)
+			}
+		})
+	}
+}
+
+func TestSplitOfTheEC2TagKey(t *testing.T) {
+	cases := []struct {
+		input             string
+		expectedOutputLen int
+		output            bool
+	}{
+		{"hello", 0, false},
+		{"kubernetes/aws-labeler", 0, false},
+		{"kubernetes/aws-labeler/label/type", 4, true},
+		{"kubernetes/aws-labeler/tail/type", 4, true},
+		{"kubernetes/aws-labeler/what/ever", 4, true},
+	}
+
+	for _, v := range cases {
+		t.Run("Input: "+v.input, func(t *testing.T) {
+			res, err := splitEC2Tag(v.input)
+			if err != nil && v.output {
+				t.Error(err.Error())
+			}
+			if err == nil && len(res) != v.expectedOutputLen {
+				t.Error("No error from the splitted function but the len is not what we expect")
+			}
+		})
+	}
+}
+
+func TestGetTaintFromEC2Tag(t *testing.T) {
+	cases := []struct {
+		input  ec2.Tag
+		output v1.Taint
+	}{
+		{
+			ec2.Tag{
+				Key:   aws.String("kubernetes/aws-labeler/tail/type"),
+				Value: aws.String("ci:NoSchedule"),
+			},
+			v1.Taint{
+				Key:    "awslabeler.com/type",
+				Value:  "ci",
+				Effect: v1.TaintEffectNoSchedule,
+			},
+		},
+		{
+			ec2.Tag{
+				Key:   aws.String("kubernetes/aws-labeler/tail/type"),
+				Value: aws.String("frontline:blabla"),
+			},
+			v1.Taint{
+				Key:    "awslabeler.com/type",
+				Value:  "frontline",
+				Effect: v1.TaintEffectNoSchedule,
+			},
+		},
+	}
+
+	for _, v := range cases {
+		t.Run("Input: "+*v.input.Key+"="+*v.input.Value, func(t *testing.T) {
+			res, err := splitEC2Tag(*v.input.Key)
+			if err != nil {
+				t.Fatal(err)
+			}
+			taint, err := getTaintFromAWSTag(res, *v.input.Value)
+			if err != nil {
+				t.Fatal(err)
+			}
+			if taint.Value != v.output.Value {
+				t.Errorf("Expected taint value %s got %s", v.output.Value, taint.Value)
+			}
+			if taint.Value != v.output.Value {
+				t.Errorf("Expected taint effect %s got %s", v.output.Effect, taint.Effect)
+			}
+			if taint.Key != v.output.Key {
+				t.Errorf("Expected taint effect %s got %s", v.output.Key, taint.Key)
+			}
+		})
+	}
+}