Avoid double slash when join url and path (#5503) (#5517)

CHANGELOG.asciidoc

@@ -43,6 +43,7 @@ https://github.com/elastic/beats/compare/v6.0.0-beta2...master[Check the HEAD di
 - Correctly send configured `Host` header to the remote server. {issue}4842[4842]
 - Fix missing ACK in redis output. {issue}5404[5404]
 - Change add_kubernetes_metadata to attempt detection of namespace. {pull}5482[5482]
+- Avoid double slash when join url and path {pull}5517[5517]
 
 *Auditbeat*
 

libbeat/outputs/elasticsearch/client.go

@@ -84,7 +84,7 @@ var (
 	errExpectedItemObject    = errors.New("expected item response object")
 	errExpectedStatusCode    = errors.New("expected item status code")
 	errUnexpectedEmptyObject = errors.New("empty object")
-	errExcpectedObjectEnd    = errors.New("expected end of object")
+	errExpectedObjectEnd     = errors.New("expected end of object")
 	errTempBulkFailure       = errors.New("temporary bulk send failure")
 )
 
@@ -505,7 +505,7 @@ func itemStatus(reader *jsonReader) (int, []byte, error) {
 		return 0, nil, err
 	}
 	if kind != dictEnd {
-		err = errExcpectedObjectEnd
+		err = errExpectedObjectEnd
 		logp.Err("Failed to parse bulk response item: %s", err)
 		return 0, nil, err
 	}

libbeat/outputs/elasticsearch/client_test.go

@@ -318,3 +318,49 @@ func TestClientWithHeaders(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Equal(t, 2, requestCount)
 }
+
+func TestAddToURL(t *testing.T) {
+	type Test struct {
+		url      string
+		path     string
+		pipeline string
+		params   map[string]string
+		expected string
+	}
+	tests := []Test{
+		{
+			url:      "localhost:9200",
+			path:     "/path",
+			pipeline: "",
+			params:   make(map[string]string),
+			expected: "localhost:9200/path",
+		},
+		{
+			url:      "localhost:9200/",
+			path:     "/path",
+			pipeline: "",
+			params:   make(map[string]string),
+			expected: "localhost:9200/path",
+		},
+		{
+			url:      "localhost:9200",
+			path:     "/path",
+			pipeline: "pipeline_1",
+			params:   make(map[string]string),
+			expected: "localhost:9200/path?pipeline=pipeline_1",
+		},
+		{
+			url:      "localhost:9200/",
+			path:     "/path",
+			pipeline: "",
+			params: map[string]string{
+				"param": "value",
+			},
+			expected: "localhost:9200/path?param=value",
+		},
+	}
+	for _, test := range tests {
+		url := addToURL(test.url, test.path, test.pipeline, test.params)
+		assert.Equal(t, url, test.expected)
+	}
+}

libbeat/outputs/elasticsearch/url.go

@@ -7,6 +7,9 @@ import (
 )
 
 func addToURL(url, path, pipeline string, params map[string]string) string {
+	if strings.HasSuffix(url, "/") && strings.HasPrefix(path, "/") {
+		url = strings.TrimSuffix(url, "/")
+	}
 	if len(params) == 0 && pipeline == "" {
 		return url + path
 	}