Added 'query' parameter to metricbeats global configuration

CHANGELOG.asciidoc

@@ -131,6 +131,7 @@ https://github.com/elastic/beats/compare/v6.4.0...master[Check the HEAD diff]
 - Allow TCP helper to support delimiters and graphite module to accept multiple metrics in a single payload. {pull}8278[8278]
 - Added 'died' PID state to process_system metricset on system module{pull}8275[8275]
 - Added `ccr` metricset to Elasticsearch module. {pull}8335[8335]
+- Added support for query params in configuration {pull}8286[8286]
 
 *Packetbeat*
 

metricbeat/mb/mb.go

@@ -22,7 +22,9 @@ to implement Modules and their associated MetricSets.
 package mb
 
 import (
+	"encoding/json"
 	"fmt"
+	"net/url"
 	"time"
 
 	"github.com/elastic/beats/libbeat/common"
@@ -306,17 +308,49 @@ type ModuleConfig struct {
 	MetricSets []string      `config:"metricsets"`
 	Enabled    bool          `config:"enabled"`
 	Raw        bool          `config:"raw"`
+	Query      QueryParams   `config:"query"`
 }
 
 func (c ModuleConfig) String() string {
 	return fmt.Sprintf(`{Module:"%v", MetricSets:%v, Enabled:%v, `+
-		`Hosts:[%v hosts], Period:"%v", Timeout:"%v", Raw:%v}`,
+		`Hosts:[%v hosts], Period:"%v", Timeout:"%v", Raw:%v, Query:%v}`,
 		c.Module, c.MetricSets, c.Enabled, len(c.Hosts), c.Period, c.Timeout,
-		c.Raw)
+		c.Raw, c.Query)
 }
 
 func (c ModuleConfig) GoString() string { return c.String() }
 
+// QueryParams is a convenient map[string]interface{} wrapper to implement the String interface which returns the
+// values in common query params format (key=value&key2=value2) which is the way that the url package expects this
+// params (without the initial '?')
+type QueryParams map[string]interface{}
+
+// String returns the values in common query params format (key=value&key2=value2) which is the way that the url
+// package expects this params (without the initial '?')
+func (q QueryParams) String() (s string) {
+	u := url.Values{}
+
+	for k, v := range q {
+		if values, ok := v.([]interface{}); ok {
+			for _, innerValue := range values {
+				u.Add(k, fmt.Sprintf("%v", innerValue))
+			}
+		} else {
+			//nil values in YAML shouldn't be stringified anyhow
+			if v == nil {
+				u.Add(k, "")
+			} else {
+				u.Add(k, fmt.Sprintf("%v", v))
+			}
+		}
+	}
+
+	byt, _ := json.MarshalIndent(u, "", "  ")
+	fmt.Println(string(byt), u.Encode())
+
+	return u.Encode()
+}
+
 // defaultModuleConfig contains the default values for ModuleConfig instances.
 var defaultModuleConfig = ModuleConfig{
 	Enabled: true,

metricbeat/mb/mb_test.go

@@ -206,7 +206,7 @@ func TestNewModulesHostParser(t *testing.T) {
 	r := newTestRegistry(t)
 
 	factory := func(base BaseMetricSet) (MetricSet, error) {
-		return &testMetricSet{base}, nil
+		return &testMetricSet{BaseMetricSet: base}, nil
 	}
 
 	hostParser := func(m Module, rawHost string) (HostData, error) {
@@ -375,3 +375,26 @@ func newConfig(t testing.TB, moduleConfig interface{}) *common.Config {
 	}
 	return config
 }
+
+func Test_QueryParams_String(t *testing.T) {
+	qp := QueryParams{
+		"stringKey": "value",
+		"intKey":    10,
+		"floatKey":  11.5,
+		"boolKey":   true,
+		"nullKey":   nil,
+		"arKey":     []interface{}{1, 2},
+	}
+
+	res := qp.String()
+
+	expectedValues := []string{"stringKey=value", "intKey=10", "floatKey=11.5", "boolKey=true", "nullKey=", "arKey=1", "arKey=2"}
+	for _, expected := range expectedValues {
+		assert.Contains(t, res, expected)
+	}
+
+	assert.NotContains(t, res, "?")
+	assert.NotContains(t, res, "%")
+	assert.NotEqual(t, "&", res[0])
+	assert.NotEqual(t, "&", res[len(res)-1])
+}

metricbeat/mb/parse/url.go

@@ -50,6 +50,16 @@ func (b URLHostParserBuilder) Build() mb.HostParser {
 			return mb.HostData{}, err
 		}
 
+		query, ok := conf["query"]
+		if ok {
+			queryMap, ok := query.(map[string]interface{})
+			if !ok {
+				return mb.HostData{}, errors.Errorf("'query' config for module %v is not a map", module.Name())
+			}
+
+			b.QueryParams = mb.QueryParams(queryMap).String()
+		}
+
 		var user, pass, path, basePath string
 		t, ok := conf["username"]
 		if ok {

metricbeat/mb/parse/url_test.go

@@ -20,6 +20,8 @@ package parse
 import (
 	"testing"
 
+	"github.com/elastic/beats/metricbeat/mb"
+
 	mbtest "github.com/elastic/beats/metricbeat/mb/testing"
 
 	"github.com/stretchr/testify/assert"
@@ -118,6 +120,7 @@ func TestURLHostParserBuilder(t *testing.T) {
 		{map[string]interface{}{"basepath": "foo/"}, URLHostParserBuilder{DefaultPath: "/default"}, "http://example.com/foo/default"},
 		{map[string]interface{}{"basepath": "/foo/"}, URLHostParserBuilder{DefaultPath: "/default"}, "http://example.com/foo/default"},
 		{map[string]interface{}{"basepath": "foo"}, URLHostParserBuilder{DefaultPath: "/default"}, "http://example.com/foo/default"},
+		{map[string]interface{}{"basepath": "foo"}, URLHostParserBuilder{DefaultPath: "/queryParams", QueryParams: mb.QueryParams{"key": "value"}.String()}, "http://example.com/foo/queryParams?key=value"},
 	}
 
 	for _, test := range cases {