Issue search support elasticsearch (#9428)

* Issue search support elasticsearch

* Fix lint

* Add indexer name on app.ini

* add a warnning on SearchIssuesByKeyword

* improve code

vendor/github.com/olivere/elastic/v7/config/config.go

@@ -0,0 +1,87 @@
+// Copyright 2012-present Oliver Eilhard. All rights reserved.
+// Use of this source code is governed by a MIT-license.
+// See http://olivere.mit-license.org/license.txt for details.
+
+package config
+
+import (
+	"fmt"
+	"net/url"
+	"strconv"
+	"strings"
+)
+
+// Config represents an Elasticsearch configuration.
+type Config struct {
+	URL         string
+	Index       string
+	Username    string
+	Password    string
+	Shards      int
+	Replicas    int
+	Sniff       *bool
+	Healthcheck *bool
+	Infolog     string
+	Errorlog    string
+	Tracelog    string
+}
+
+// Parse returns the Elasticsearch configuration by extracting it
+// from the URL, its path, and its query string.
+//
+// Example:
+//   http://127.0.0.1:9200/store-blobs?shards=1&replicas=0&sniff=false&tracelog=elastic.trace.log
+//
+// The code above will return a URL of http://127.0.0.1:9200, an index name
+// of store-blobs, and the related settings from the query string.
+func Parse(elasticURL string) (*Config, error) {
+	cfg := &Config{
+		Shards:   1,
+		Replicas: 0,
+		Sniff:    nil,
+	}
+
+	uri, err := url.Parse(elasticURL)
+	if err != nil {
+		return nil, fmt.Errorf("error parsing elastic parameter %q: %v", elasticURL, err)
+	}
+	index := strings.TrimSuffix(strings.TrimPrefix(uri.Path, "/"), "/")
+	if uri.User != nil {
+		cfg.Username = uri.User.Username()
+		cfg.Password, _ = uri.User.Password()
+	}
+	uri.User = nil
+
+	if i, err := strconv.Atoi(uri.Query().Get("shards")); err == nil {
+		cfg.Shards = i
+	}
+	if i, err := strconv.Atoi(uri.Query().Get("replicas")); err == nil {
+		cfg.Replicas = i
+	}
+	if s := uri.Query().Get("sniff"); s != "" {
+		if b, err := strconv.ParseBool(s); err == nil {
+			cfg.Sniff = &b
+		}
+	}
+	if s := uri.Query().Get("healthcheck"); s != "" {
+		if b, err := strconv.ParseBool(s); err == nil {
+			cfg.Healthcheck = &b
+		}
+	}
+	if s := uri.Query().Get("infolog"); s != "" {
+		cfg.Infolog = s
+	}
+	if s := uri.Query().Get("errorlog"); s != "" {
+		cfg.Errorlog = s
+	}
+	if s := uri.Query().Get("tracelog"); s != "" {
+		cfg.Tracelog = s
+	}
+
+	uri.Path = ""
+	uri.RawQuery = ""
+	cfg.URL = uri.String()
+	cfg.Index = index
+
+	return cfg, nil
+}