Move http_endpoint input to v2 input API (elastic#19815)

Author: Steffen Siering

x-pack/filebeat/include/list.go

@@ -11,6 +11,7 @@ import (
 	"github.com/elastic/beats/v7/libbeat/beat"
 	"github.com/elastic/beats/v7/libbeat/logp"
 	"github.com/elastic/beats/v7/x-pack/filebeat/input/cloudfoundry"
+	"github.com/elastic/beats/v7/x-pack/filebeat/input/http_endpoint"
 	"github.com/elastic/beats/v7/x-pack/filebeat/input/o365audit"
 )
 
@@ -23,7 +24,8 @@ func Init(info beat.Info, log *logp.Logger, store beater.StateStore) []v2.Plugin
 
 func xpackInputs(info beat.Info, log *logp.Logger, store beater.StateStore) []v2.Plugin {
 	return []v2.Plugin{
-		o365audit.Plugin(log, store),
 		cloudfoundry.Plugin(),
+		http_endpoint.Plugin(),
+		o365audit.Plugin(log, store),
 	}
 }

x-pack/filebeat/input/default-inputs/inputs.go

@@ -44,5 +44,11 @@ func (c *config) Validate() error {
 		return errors.New("response_body must be valid JSON")
 	}
 
+	if c.BasicAuth {
+		if c.Username == "" || c.Password == "" {
+			return errors.New("Username and password required when basicauth is enabled")
+		}
+	}
+
 	return nil
 }

x-pack/filebeat/input/http_endpoint/config.go

@@ -0,0 +1,109 @@
+// Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+// or more contributor license agreements. Licensed under the Elastic License;
+// you may not use this file except in compliance with the Elastic License.
+
+package http_endpoint
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"time"
+
+	stateless "github.com/elastic/beats/v7/filebeat/input/v2/input-stateless"
+	"github.com/elastic/beats/v7/libbeat/beat"
+	"github.com/elastic/beats/v7/libbeat/common"
+	"github.com/elastic/beats/v7/libbeat/logp"
+)
+
+type httpHandler struct {
+	log       *logp.Logger
+	publisher stateless.Publisher
+
+	messageField string
+	responseCode int
+	responseBody string
+}
+
+var errBodyEmpty = errors.New("Body cannot be empty")
+var errUnsupportedType = errors.New("Only JSON objects are accepted")
+
+// Triggers if middleware validation returns successful
+func (h *httpHandler) apiResponse(w http.ResponseWriter, r *http.Request) {
+	obj, status, err := httpReadJsonObject(r.Body)
+	if err != nil {
+		w.Header().Add("Content-Type", "application/json")
+		sendErrorResponse(w, status, err)
+		return
+	}
+
+	h.publishEvent(obj)
+	w.Header().Add("Content-Type", "application/json")
+	h.sendResponse(w, h.responseCode, h.responseBody)
+}
+
+func (h *httpHandler) sendResponse(w http.ResponseWriter, status int, message string) {
+	w.WriteHeader(status)
+	io.WriteString(w, message)
+}
+
+func (h *httpHandler) publishEvent(obj common.MapStr) {
+	event := beat.Event{
+		Timestamp: time.Now().UTC(),
+		Fields: common.MapStr{
+			h.messageField: obj,
+		},
+	}
+
+	h.publisher.Publish(event)
+}
+
+func withValidator(v validator, handler http.HandlerFunc) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if status, err := v.ValidateHeader(r); status != 0 && err != nil {
+			sendErrorResponse(w, status, err)
+		} else {
+			handler(w, r)
+		}
+	}
+}
+
+func sendErrorResponse(w http.ResponseWriter, status int, err error) {
+	w.Header().Add("Content-Type", "application/json")
+	w.WriteHeader(status)
+	fmt.Fprintf(w, `{"message": %q}`, err.Error())
+}
+
+func httpReadJsonObject(body io.Reader) (obj common.MapStr, status int, err error) {
+	if body == http.NoBody {
+		return nil, http.StatusNotAcceptable, errBodyEmpty
+	}
+
+	contents, err := ioutil.ReadAll(body)
+	if err != nil {
+		return nil, http.StatusInternalServerError, fmt.Errorf("failed reading body: %w", err)
+	}
+
+	if !isObject(contents) {
+		return nil, http.StatusBadRequest, errUnsupportedType
+	}
+
+	obj = common.MapStr{}
+	if err := json.Unmarshal(contents, &obj); err != nil {
+		return nil, http.StatusBadRequest, fmt.Errorf("Malformed JSON body: %w", err)
+	}
+
+	return obj, 0, nil
+}
+
+func isObject(b []byte) bool {
+	obj := bytes.TrimLeft(b, " \t\r\n")
+	if len(obj) > 0 && obj[0] == '{' {
+		return true
+	}
+	return false
+}