Add XML payload to Webhooks/HTTP

README.md

@@ -76,7 +76,8 @@ receivers:
 ### Webhooks/HTTP
 
 Webhooks are the easiest way of integrating this tool to external systems. It allows templating & custom headers which
-allows you to push events to many possible sources out there. See [Customizing Payload] for more information.
+allows you to push events to many possible sources out there. See [Customizing Payload](#customizing-payload) for more information.
+In addition Webhooks/HTTP support XML payload, specifying header `Content-Type: application/xml`. See [XML Payload](#xml-payload) for more information.
 
 ```yaml
 # ...
@@ -89,6 +90,77 @@ receivers:
         User-Agent: kube-event-exporter 1.0
       layout: # Optional
 ```
+#### XML payload
+```yaml
+# ...
+receivers:
+  - name: "alerts"
+    webhook:
+      endpoint: "https://my-super-secret-service.com"
+      headers:
+        X-API-KEY: "123"
+        User-Agent: kube-event-exporter 1.0
+        Content-Type: "application/xml"
+      layout: # Optional
+```
+
+Resulting XML payload differ if there is a root key or not. Root key is used as root tag in XML payload, otherwise root tag is `<doc>`.
+
+With root key
+```yaml
+# ...
+receivers:
+  - name: "alerts"
+    webhook:
+      endpoint: "https://my-super-secret-service.com"
+      headers:
+        Content-Type: "application/xml"
+      layout:
+        event:
+          region: "us-west-2"
+          eventType: "kubernetes-event"
+          type: "{{ .Type }}"
+          count: "{{ .Count }}"
+```
+
+XML payload
+```xml
+<?xml version="1.0" encoding="UTF-8"?>
+<event>
+   <count>23</count>
+   <eventType>kubernetes-event</eventType>
+   <region>us-west-2</region>
+   <type>Warning</type>
+</event>
+```
+
+Without root key
+```yaml
+# ...
+receivers:
+  - name: "alerts"
+    webhook:
+      endpoint: "https://my-super-secret-service.com"
+      headers:
+        Content-Type: "application/xml"
+      layout:
+        region: "us-west-2"
+        eventType: "kubernetes-event"
+        type: "{{ .Type }}"
+        count: "{{ .Count }}"
+```
+
+XML payload
+```xml
+<?xml version="1.0" encoding="UTF-8"?>
+<doc>
+   <count>23</count>
+   <eventType>kubernetes-event</eventType>
+   <region>us-west-2</region>
+   <type>Warning</type>
+</doc>
+```
+
 
 ### Elasticsearch
 

go.mod

@@ -6,6 +6,7 @@ require (
 	cloud.google.com/go/bigquery v1.9.0
 	cloud.google.com/go/pubsub v1.3.1
 	github.com/Masterminds/sprig v2.22.0+incompatible
+	github.com/clbanning/mxj v1.8.4
 	github.com/Shopify/sarama v1.24.1
 	github.com/aws/aws-sdk-go v1.41.19
 	github.com/elastic/go-elasticsearch/v7 v7.4.1

go.sum

@@ -63,6 +63,8 @@ github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA
 github.com/chzyer/logex v1.1.10/go.mod h1:+Ywpsq7O8HXn0nuIou7OrIPyXbp3wmkHB+jjWRnGsAI=
 github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e/go.mod h1:nSuG5e5PlCu98SY8svDHJxuZscDgtXS6KTTbou5AhLI=
 github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1/go.mod h1:Q3SI9o4m/ZMnBNeIyt5eFwwo7qiLfzFZmjNmxjkiQlU=
+github.com/clbanning/mxj v1.8.4 h1:HuhwZtbyvyOw+3Z1AowPkU87JkJUSv751ELWaiTpj8I=
+github.com/clbanning/mxj v1.8.4/go.mod h1:BVjHeAH+rl9rs6f+QIpeRl0tfu10SXn1pUSa5PVGJng=
 github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
 github.com/cncf/udpa/go v0.0.0-20191209042840-269d4d468f6f/go.mod h1:M8M6+tZqaGXZJjfX53e64911xZQV5JYwmTeXPW+k8Sc=
 github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=

pkg/sinks/tmpl.go

@@ -3,9 +3,12 @@ package sinks
 import (
 	"bytes"
 	"encoding/json"
+	"encoding/xml"
+	"text/template"
+
 	"github.com/Masterminds/sprig"
+	"github.com/clbanning/mxj"
 	"github.com/opsgenie/kubernetes-event-exporter/pkg/kube"
-	"text/template"
 )
 
 func GetString(event *kube.EnhancedEvent, text string) (string, error) {
@@ -98,3 +101,51 @@ func serializeEventWithLayout(layout map[string]interface{}, ev *kube.EnhancedEv
 	}
 	return toSend, nil
 }
+
+func serializeXMLEventWithLayout(layout map[string]interface{}, ev *kube.EnhancedEvent) ([]byte, error) {
+	var (
+		err     error
+		toSend  []byte
+		obj     interface{}
+		rootTag string = mxj.DefaultRootTag
+	)
+
+	if layout != nil {
+		res, err := convertLayoutTemplate(layout, ev)
+		if err != nil {
+			return nil, err
+		}
+
+		if len(res) == 1 {
+
+			for k, v := range res {
+				rootTag = k
+				obj = v
+			}
+		} else {
+
+			obj = res
+		}
+
+	} else {
+		// convert event to map
+		// TODO: create benchmark to check if reflect version is more performant
+		mrv := make(map[string]interface{})
+		jsonRepr, err := json.Marshal(ev)
+		if err != nil {
+			return nil, err
+		}
+		err = json.Unmarshal(jsonRepr, &mrv)
+		if err != nil {
+			return nil, err
+		}
+		obj = mrv
+	}
+
+	toSend, err = mxj.AnyXml(obj, rootTag)
+	if err != nil {
+		return nil, err
+	}
+
+	return []byte(xml.Header + string(toSend)), nil
+}

pkg/sinks/tmpl_test.go

@@ -1,21 +1,29 @@
 package sinks
 
 import (
+	"testing"
+	"time"
+
+	"github.com/clbanning/mxj"
 	"github.com/opsgenie/kubernetes-event-exporter/pkg/kube"
 	"github.com/stretchr/testify/require"
 	v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	"testing"
-	"time"
 )
 
-func TestLayoutConvert(t *testing.T) {
+func newTestEvent() *kube.EnhancedEvent {
 	ev := &kube.EnhancedEvent{}
 	ev.Namespace = "default"
 	ev.Type = "Warning"
+	ev.Count = 23
 	ev.InvolvedObject.Kind = "Pod"
 	ev.InvolvedObject.Name = "nginx-server-123abc-456def"
 	ev.Message = "Successfully pulled image \"nginx:latest\""
 	ev.FirstTimestamp = v1.Time{Time: time.Now()}
+	return ev
+}
+
+func TestLayoutConvert(t *testing.T) {
+	ev := newTestEvent()
 
 	// Because Go, when parsing yaml, its []interface, not []string
 	var tagz interface{}
@@ -50,3 +58,74 @@ func TestLayoutConvert(t *testing.T) {
 
 	require.Equal(t, val2, ev.Message)
 }
+
+var xmltests = []struct {
+	name         string
+	layout       map[string]interface{}
+	expectedRoot string
+}{
+	{
+		"XML with root node",
+		map[string]interface{}{
+			"event": map[interface{}]interface{}{
+				"title":     "{{ .InvolvedObject.Name }}",
+				"severity":  "{{ .Type }}",
+				"Count":     "{{ .Count }}",
+				"eventType": "kube-event",
+				"region":    "us-west-2",
+				"createdAt": "{{ .GetTimestampMs }}",
+			}},
+		"event",
+	},
+	{
+		"XML without root node",
+		map[string]interface{}{
+			"title":     "{{ .InvolvedObject.Name }}",
+			"severity":  "{{ .Type }}",
+			"Count":     "{{ .Count }}",
+			"eventType": "kube-event",
+			"region":    "us-west-2",
+			"createdAt": "{{ .GetTimestampMs }}",
+		},
+		"doc",
+	},
+	{
+		"XML format k8s event (no layout)",
+		nil,
+		"doc",
+	},
+}
+
+func TestXMLEventWithLayout(t *testing.T) {
+	ev := newTestEvent()
+
+	for _, tt := range xmltests {
+		t.Run(tt.name, func(t *testing.T) {
+			res, err := serializeXMLEventWithLayout(tt.layout, ev)
+
+			require.NoError(t, err)
+
+			//t.Logf("res: %v", string(res))
+
+			m, err := mxj.NewMapXml(res, true)
+
+			require.NoError(t, err)
+
+			root, ok := m[tt.expectedRoot].(map[string]interface{})
+
+			require.True(t, ok)
+
+			if tt.layout != nil {
+				require.Equal(t, root["title"], "nginx-server-123abc-456def")
+				require.Equal(t, root["severity"], "Warning")
+				require.Equal(t, root["region"], "us-west-2")
+				require.Equal(t, root["Count"], 23.0) // mxj unmarshal try to cast only to boolean or float64
+			} else {
+				require.Equal(t, root["involvedObject"].(map[string]interface{})["name"], "nginx-server-123abc-456def")
+				require.Equal(t, root["type"], "Warning")
+				require.Equal(t, root["count"], 23.0) // mxj unmarshal try to cast only to boolean or float64
+			}
+
+		})
+	}
+}

pkg/sinks/webhook.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"io/ioutil"
 	"net/http"
+	"strings"
 
 	"github.com/opsgenie/kubernetes-event-exporter/pkg/kube"
 )
@@ -18,20 +19,65 @@ type WebhookConfig struct {
 	Headers  map[string]string      `yaml:"headers"`
 }
 
+type serializeEvent func(layout map[string]interface{}, ev *kube.EnhancedEvent) ([]byte, error)
+
+var mimetypeConverter = map[string]serializeEvent{
+	"application/json": serializeEventWithLayout,
+	"application/xml":  serializeXMLEventWithLayout,
+}
+
 func NewWebhook(cfg *WebhookConfig) (Sink, error) {
-	return &Webhook{cfg: cfg}, nil
+
+	var contentType = ""
+	var converter serializeEvent
+
+	for k, v := range cfg.Headers {
+
+		if strings.Contains(strings.ToLower(k), "content-type") {
+			contentType = v
+			break
+		}
+	}
+
+	if contentType == "" {
+		// default
+		contentType = "application/json"
+		cfg.Headers["Content-Type"] = "application/json"
+	}
+
+	for k, v := range mimetypeConverter {
+		if strings.Contains(contentType, k) {
+			converter = v
+			break
+		}
+	}
+
+	if converter == nil {
+
+		errMsg := "Wrong Content-Type in headers: only %s are supported"
+		mimetypes := ""
+		for k := range mimetypeConverter {
+			mimetypes = mimetypes + ", " + k
+		}
+
+		return nil, fmt.Errorf(errMsg, mimetypes)
+	}
+
+	return &Webhook{cfg: cfg, serializer: converter}, nil
 }
 
 type Webhook struct {
-	cfg *WebhookConfig
+	cfg        *WebhookConfig
+	serializer serializeEvent
 }
 
 func (w *Webhook) Close() {
 	// No-op
 }
 
 func (w *Webhook) Send(ctx context.Context, ev *kube.EnhancedEvent) error {
-	reqBody, err := serializeEventWithLayout(w.cfg.Layout, ev)
+
+	reqBody, err := w.serializer(w.cfg.Layout, ev)
 	if err != nil {
 		return err
 	}
@@ -40,10 +86,11 @@ func (w *Webhook) Send(ctx context.Context, ev *kube.EnhancedEvent) error {
 	if err != nil {
 		return err
 	}
-	req.Header.Add("Content-Type", "application/json")
+
 	for k, v := range w.cfg.Headers {
 		req.Header.Add(k, v)
 	}
+
 	tlsClientConfig, err := setupTLS(&w.cfg.TLS)
 	if err != nil {
 		return fmt.Errorf("failed to setup TLS: %w", err)