VictoriaMetrics/app/vmagent/remotewrite/client.go
Aliaksandr Valialkin cb8c6908dc app/vmagent/remotewrite: create new request on failure to send a block of data to remote storage
Previously the request body was already consumed before the retry, so this led to the following error:

    http: ContentLength=... with Body length 0
2020-07-27 17:32:46 +03:00

247 lines
8.8 KiB
Go

package remotewrite
import (
"bytes"
"crypto/tls"
"encoding/base64"
"flag"
"fmt"
"io/ioutil"
"net/http"
"net/url"
"strings"
"sync"
"time"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/flagutil"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/persistentqueue"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/promauth"
"github.com/VictoriaMetrics/metrics"
)
var (
sendTimeout = flag.Duration("remoteWrite.sendTimeout", time.Minute, "Timeout for sending a single block of data to -remoteWrite.url")
proxyURL = flagutil.NewArray("remoteWrite.proxyURL", "Optional proxy URL for writing data to -remoteWrite.url. Supported proxies: http, https, socks5. "+
"Example: -remoteWrite.proxyURL=socks5://proxy:1234")
tlsInsecureSkipVerify = flag.Bool("remoteWrite.tlsInsecureSkipVerify", false, "Whether to skip tls verification when connecting to -remoteWrite.url")
tlsCertFile = flagutil.NewArray("remoteWrite.tlsCertFile", "Optional path to client-side TLS certificate file to use when connecting to -remoteWrite.url. "+
"If multiple args are set, then they are applied independently for the corresponding -remoteWrite.url")
tlsKeyFile = flagutil.NewArray("remoteWrite.tlsKeyFile", "Optional path to client-side TLS certificate key to use when connecting to -remoteWrite.url. "+
"If multiple args are set, then they are applied independently for the corresponding -remoteWrite.url")
tlsCAFile = flagutil.NewArray("remoteWrite.tlsCAFile", "Optional path to TLS CA file to use for verifying connections to -remoteWrite.url. "+
"By default system CA is used. If multiple args are set, then they are applied independently for the corresponding -remoteWrite.url")
tlsServerName = flagutil.NewArray("remoteWrite.tlsServerName", "Optional TLS server name to use for connections to -remoteWrite.url. "+
"By default the server name from -remoteWrite.url is used. If multiple args are set, then they are applied independently for the corresponding -remoteWrite.url")
basicAuthUsername = flagutil.NewArray("remoteWrite.basicAuth.username", "Optional basic auth username to use for -remoteWrite.url. "+
"If multiple args are set, then they are applied independently for the corresponding -remoteWrite.url")
basicAuthPassword = flagutil.NewArray("remoteWrite.basicAuth.password", "Optional basic auth password to use for -remoteWrite.url. "+
"If multiple args are set, then they are applied independently for the corresponding -remoteWrite.url")
bearerToken = flagutil.NewArray("remoteWrite.bearerToken", "Optional bearer auth token to use for -remoteWrite.url. "+
"If multiple args are set, then they are applied independently for the corresponding -remoteWrite.url")
)
type client struct {
urlLabelValue string
remoteWriteURL string
authHeader string
fq *persistentqueue.FastQueue
hc *http.Client
requestDuration *metrics.Histogram
requestsOKCount *metrics.Counter
errorsCount *metrics.Counter
retriesCount *metrics.Counter
wg sync.WaitGroup
stopCh chan struct{}
}
func newClient(argIdx int, remoteWriteURL, urlLabelValue string, fq *persistentqueue.FastQueue, concurrency int) *client {
tlsCfg, err := getTLSConfig(argIdx)
if err != nil {
logger.Panicf("FATAL: cannot initialize TLS config: %s", err)
}
tr := &http.Transport{
Dial: statDial,
TLSClientConfig: tlsCfg,
TLSHandshakeTimeout: 5 * time.Second,
MaxConnsPerHost: 2 * concurrency,
WriteBufferSize: 16 * 1024,
}
pURL := proxyURL.GetOptionalArg(argIdx)
if len(pURL) > 0 {
if !strings.Contains(pURL, "://") {
logger.Fatalf("cannot parse -remoteWrite.proxyURL=%q: it must start with `http://`, `https://` or `socks5://`", pURL)
}
urlProxy, err := url.Parse(pURL)
if err != nil {
logger.Fatalf("cannot parse -remoteWrite.proxyURL=%q: %s", pURL, err)
}
tr.Proxy = http.ProxyURL(urlProxy)
}
authHeader := ""
username := basicAuthUsername.GetOptionalArg(argIdx)
password := basicAuthPassword.GetOptionalArg(argIdx)
if len(username) > 0 || len(password) > 0 {
// See https://en.wikipedia.org/wiki/Basic_access_authentication
token := username + ":" + password
token64 := base64.StdEncoding.EncodeToString([]byte(token))
authHeader = "Basic " + token64
}
token := bearerToken.GetOptionalArg(argIdx)
if len(token) > 0 {
if authHeader != "" {
logger.Fatalf("`-remoteWrite.bearerToken`=%q cannot be set when `-remoteWrite.basicAuth.*` flags are set", token)
}
authHeader = "Bearer " + token
}
c := &client{
urlLabelValue: urlLabelValue,
remoteWriteURL: remoteWriteURL,
authHeader: authHeader,
fq: fq,
hc: &http.Client{
Transport: tr,
Timeout: *sendTimeout,
},
stopCh: make(chan struct{}),
}
c.requestDuration = metrics.GetOrCreateHistogram(fmt.Sprintf(`vmagent_remotewrite_duration_seconds{url=%q}`, c.urlLabelValue))
c.requestsOKCount = metrics.GetOrCreateCounter(fmt.Sprintf(`vmagent_remotewrite_requests_total{url=%q, status_code="2XX"}`, c.urlLabelValue))
c.errorsCount = metrics.GetOrCreateCounter(fmt.Sprintf(`vmagent_remotewrite_errors_total{url=%q}`, c.urlLabelValue))
c.retriesCount = metrics.GetOrCreateCounter(fmt.Sprintf(`vmagent_remotewrite_retries_count_total{url=%q}`, c.urlLabelValue))
for i := 0; i < concurrency; i++ {
c.wg.Add(1)
go func() {
defer c.wg.Done()
c.runWorker()
}()
}
logger.Infof("initialized client for -remoteWrite.url=%q", c.remoteWriteURL)
return c
}
func (c *client) MustStop() {
close(c.stopCh)
c.wg.Wait()
logger.Infof("stopped client for -remoteWrite.url=%q", c.remoteWriteURL)
}
func getTLSConfig(argIdx int) (*tls.Config, error) {
c := &promauth.TLSConfig{
CAFile: tlsCAFile.GetOptionalArg(argIdx),
CertFile: tlsCertFile.GetOptionalArg(argIdx),
KeyFile: tlsKeyFile.GetOptionalArg(argIdx),
ServerName: tlsServerName.GetOptionalArg(argIdx),
InsecureSkipVerify: *tlsInsecureSkipVerify,
}
if c.CAFile == "" && c.CertFile == "" && c.KeyFile == "" && c.ServerName == "" && !c.InsecureSkipVerify {
return nil, nil
}
cfg, err := promauth.NewConfig(".", nil, "", "", c)
if err != nil {
return nil, fmt.Errorf("cannot populate TLS config: %w", err)
}
tlsCfg := cfg.NewTLSConfig()
return tlsCfg, nil
}
func (c *client) runWorker() {
var ok bool
var block []byte
ch := make(chan struct{})
for {
block, ok = c.fq.MustReadBlock(block[:0])
if !ok {
return
}
go func() {
c.sendBlock(block)
ch <- struct{}{}
}()
select {
case <-ch:
// The block has been sent successfully
continue
case <-c.stopCh:
// c must be stopped. Wait for a while in the hope the block will be sent.
graceDuration := 5 * time.Second
select {
case <-ch:
// The block has been sent successfully.
case <-time.After(graceDuration):
logger.Errorf("couldn't sent block with size %d bytes to %q in %.3f seconds during shutdown; dropping it",
len(block), c.remoteWriteURL, graceDuration.Seconds())
}
return
}
}
}
func (c *client) sendBlock(block []byte) {
retryDuration := time.Second
again:
req, err := http.NewRequest("POST", c.remoteWriteURL, bytes.NewBuffer(block))
if err != nil {
logger.Panicf("BUG: unexected error from http.NewRequest(%q): %s", c.remoteWriteURL, err)
}
h := req.Header
h.Set("User-Agent", "vmagent")
h.Set("Content-Type", "application/x-protobuf")
h.Set("Content-Encoding", "snappy")
h.Set("X-Prometheus-Remote-Write-Version", "0.1.0")
if c.authHeader != "" {
req.Header.Set("Authorization", c.authHeader)
}
startTime := time.Now()
resp, err := c.hc.Do(req)
c.requestDuration.UpdateDuration(startTime)
if err != nil {
c.errorsCount.Inc()
retryDuration *= 2
if retryDuration > time.Minute {
retryDuration = time.Minute
}
logger.Errorf("couldn't send a block with size %d bytes to %q: %s; re-sending the block in %.3f seconds",
len(block), c.remoteWriteURL, err, retryDuration.Seconds())
t := time.NewTimer(retryDuration)
select {
case <-c.stopCh:
t.Stop()
return
case <-t.C:
}
c.retriesCount.Inc()
goto again
}
statusCode := resp.StatusCode
if statusCode/100 != 2 {
metrics.GetOrCreateCounter(fmt.Sprintf(`vmagent_remotewrite_requests_total{url=%q, status_code="%d"}`, c.urlLabelValue, statusCode)).Inc()
retryDuration *= 2
if retryDuration > time.Minute {
retryDuration = time.Minute
}
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
logger.Errorf("cannot read response body from %q: %s", c.remoteWriteURL, err)
} else {
logger.Errorf("unexpected status code received after sending a block with size %d bytes to %q: %d; response body=%q; re-sending the block in %.3f seconds",
len(block), c.remoteWriteURL, statusCode, body, retryDuration.Seconds())
}
t := time.NewTimer(retryDuration)
select {
case <-c.stopCh:
t.Stop()
return
case <-t.C:
}
c.retriesCount.Inc()
goto again
}
c.requestsOKCount.Inc()
}