parsed uploaders client during startup

* parsed tls configs during startup instead of during upload operation
* reuse http client for uploaders

uploader/base.go

@@ -18,7 +18,6 @@ import (
 
 	"go.uber.org/zap"
 
-	"github.com/lomik/carbon-clickhouse/helper/config"
 	"github.com/lomik/carbon-clickhouse/helper/stop"
 )
 
@@ -237,41 +236,21 @@ func (u *Base) insertRowBinary(table string, data io.Reader) error {
 
 	q.Set("query", fmt.Sprintf("INSERT INTO %s FORMAT RowBinary", table))
 	p.RawQuery = q.Encode()
-	queryUrl := p.String()
+	queryURL := p.String()
 
 	var req *http.Request
 
 	if u.config.CompressData {
-		req, err = http.NewRequest("POST", queryUrl, compress(data))
+		req, err = http.NewRequest("POST", queryURL, compress(data))
 		req.Header.Add("Content-Encoding", "gzip")
 	} else {
-		req, err = http.NewRequest("POST", queryUrl, data)
+		req, err = http.NewRequest("POST", queryURL, data)
 	}
 
 	if err != nil {
 		return err
 	}
-
-	transport := &http.Transport{DisableKeepAlives: true}
-
-	if u.config.TLS != nil {
-		tlsConfig, warns, err := config.ParseClientTLSConfig(u.config.TLS)
-		if err != nil {
-			return err
-		}
-		if len(warns) > 0 {
-			u.logger.Warn("insecure options detected, while parsing HTTP Client TLS Config for uploader",
-				zap.Strings("warnings", warns),
-			)
-		}
-		transport.TLSClientConfig = tlsConfig
-	}
-
-	client := &http.Client{
-		Timeout:   u.config.Timeout.Value(),
-		Transport: transport,
-	}
-	resp, err := client.Do(req)
+	resp, err := u.config.client.Do(req)
 	if err != nil {
 		return err
 	}

uploader/config.go

@@ -2,8 +2,14 @@ package uploader
 
 import (
 	"fmt"
+	"net/http"
+	"net/url"
 	"time"
 
+	"go.uber.org/zap"
+
+	"github.com/lomik/zapwriter"
+
 	"github.com/lomik/carbon-clickhouse/helper/config"
 )
 
@@ -19,11 +25,12 @@ type Config struct {
 	URL                  string              `toml:"url"`
 	CacheTTL             *config.Duration    `toml:"cache-ttl"`
 	IgnoredPatterns      []string            `toml:"ignored-patterns,omitempty"` // points, points-reverse
-	CompressData         bool                `toml:"compress-data"`              //compress data while sending to clickhouse
+	CompressData         bool                `toml:"compress-data"`              // compress data while sending to clickhouse
 	IgnoredTaggedMetrics []string            `toml:"ignored-tagged-metrics"`     // for tagged table; create only `__name__` tag for these metrics and ignore others
 	Hash                 string              `toml:"hash"`                       // in index uploader store hash in memory instead of full metric
 	DisableDailyIndex    bool                `toml:"disable-daily-index"`        // do not calculate and upload daily index to ClickHouse
 	hashFunc             func(string) string `toml:"-"`
+	client               *http.Client        `toml:"-"`
 }
 
 func (cfg *Config) Parse() error {
@@ -36,11 +43,42 @@ func (cfg *Config) Parse() error {
 		}
 	}
 
+	if cfg.Timeout == nil {
+		cfg.Timeout = &config.Duration{Duration: time.Minute}
+	}
+
 	var known bool
 	cfg.hashFunc, known = knownHash[cfg.Hash]
 	if !known {
 		return fmt.Errorf("unknown hash function %#v", cfg.Hash)
 	}
 
+	cfg.client = &http.Client{
+		Timeout: cfg.Timeout.Value(),
+	}
+	if cfg.TLS != nil {
+		tlsConfig, warns, err := config.ParseClientTLSConfig(cfg.TLS)
+		if err != nil {
+			return err
+		}
+		p, err := url.Parse(cfg.URL)
+		if err != nil {
+			return err
+		}
+		if p.Scheme == "https" {
+			cfg.client.Transport = &http.Transport{
+				TLSClientConfig: tlsConfig,
+			}
+		} else {
+			warns = append(warns, "TLS configurations is ignored because scheme is not HTTPS")
+		}
+		if len(warns) > 0 {
+			logger := zapwriter.Logger("config")
+			logger.Warn("insecure options detected, while parsing HTTP Client TLS Config for uploader",
+				zap.Strings("warnings", warns),
+			)
+		}
+	}
+
 	return nil
 }