Stop filebeat if filebeat is started without any prospectors defined

filebeat/beat/filebeat.go

@@ -91,7 +91,10 @@ func (fb *Filebeat) Run(b *beat.Beat) error {
 	// Start up spooler
 	go fb.Spooler.Run()
 
-	crawl.Start(fb.FbConfig.Filebeat.Prospectors, fb.Spooler.Channel)
+	err = crawl.Start(fb.FbConfig.Filebeat.Prospectors, fb.Spooler.Channel)
+	if err != nil {
+		return err
+	}
 
 	// Publishes event to output
 	go Publish(b, fb)

filebeat/crawler/crawler.go

@@ -27,18 +27,22 @@ type Crawler struct {
 	running   bool
 }
 
-func (crawler *Crawler) Start(files []config.ProspectorConfig, eventChan chan *input.FileEvent) {
+func (crawler *Crawler) Start(prospectorConfigs []config.ProspectorConfig, eventChan chan *input.FileEvent) error {
 
 	pendingProspectorCnt := 0
 	crawler.running = true
 
+	if len(prospectorConfigs) == 0 {
+		return fmt.Errorf("No prospectors defined. You must have at least one prospector defined in the config file.")
+	}
+
 	// Prospect the globs/paths given on the command line and launch harvesters
-	for _, fileconfig := range files {
+	for _, prospectorConfig := range prospectorConfigs {
 
-		logp.Debug("prospector", "File Configs: %v", fileconfig.Paths)
+		logp.Debug("prospector", "File Configs: %v", prospectorConfig.Paths)
 
 		prospector := &Prospector{
-			ProspectorConfig: fileconfig,
+			ProspectorConfig: prospectorConfig,
 			registrar:        crawler.Registrar,
 		}
 
@@ -76,6 +80,8 @@ func (crawler *Crawler) Start(files []config.ProspectorConfig, eventChan chan *i
 	}
 
 	logp.Info("All prospectors initialised with %d states to persist", len(crawler.Registrar.State))
+
+	return nil
 }
 
 func (crawler *Crawler) Stop() {

filebeat/crawler/crawler_test.go

@@ -0,0 +1,19 @@
+package crawler
+
+import (
+	"testing"
+
+	"github.com/elastic/beats/filebeat/config"
+	"github.com/elastic/beats/filebeat/input"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCrawlerStartError(t *testing.T) {
+	crawler := Crawler{}
+	channel := make(chan *input.FileEvent, 1)
+	prospectorConfigs := []config.ProspectorConfig{}
+
+	error := crawler.Start(prospectorConfigs, channel)
+
+	assert.Error(t, error)
+}

filebeat/tests/system/config/filebeat.yml.j2

@@ -1,6 +1,10 @@
 ############################# Filebeat ######################################
 filebeat:
   prospectors:
+    {% if prospectors is not defined %}
+    {% set prospectors = true %}
+    {% endif %}
+    {% if prospectors %}
     -
       # Paths that should be crawled and fetched
       {% if path %}paths:
@@ -48,7 +52,7 @@ filebeat:
         timeout: 1s
         max_lines: {{ max_lines|default(500) }}
       {% endif %}
-
+    {% endif %}
   spool_size:
   idle_timeout: 0.1s
   registry_file: {{ fb.working_dir + '/' }}{{ registryFile|default(".filebeat")}}

filebeat/tests/system/test_prospector.py

@@ -231,3 +231,21 @@ def test_rotating_ignore_older_low_write_rate(self):
             max_timeout=5)
 
         proc.kill_and_wait()
+
+    def test_shutdown_no_prospectors(self):
+        self.render_config_template(
+                prospectors=False,
+        )
+
+        proc = self.start_filebeat(debug_selectors=['*'])
+
+        # wait for first  "Start next scan" log message
+        self.wait_until(
+            lambda: self.log_contains(
+                "No prospectors defined"),
+            max_timeout=10)
+
+        self.wait_until(
+            lambda: self.log_contains(
+                 "shutting down"),
+            max_timeout=10)