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proxy.go
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proxy.go
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package main
import (
"bytes"
"context"
"errors"
"fmt"
"io"
"net"
"net/http"
"net/http/httputil"
"net/url"
"strconv"
"strings"
"sync"
"time"
"github.com/contentsquare/chproxy/cache"
"github.com/contentsquare/chproxy/config"
"github.com/contentsquare/chproxy/internal/topology"
"github.com/contentsquare/chproxy/log"
"github.com/prometheus/client_golang/prometheus"
)
// tmpDir temporary path to store ongoing queries results
const tmpDir = "/tmp"
// failedTransactionPrefix prefix added to the failed reason for concurrent queries registry
const failedTransactionPrefix = "[concurrent query failed]"
type reverseProxy struct {
rp *httputil.ReverseProxy
// configLock serializes access to applyConfig.
// It protects reload* fields.
configLock sync.Mutex
reloadSignal chan struct{}
reloadWG sync.WaitGroup
// lock protects users, clusters and caches.
// RWMutex enables concurrent access to getScope.
lock sync.RWMutex
users map[string]*user
clusters map[string]*cluster
caches map[string]*cache.AsyncCache
hasWildcarded bool
maxIdleConns int
maxIdleConnsPerHost int
maxErrorReasonSize int64
}
func newReverseProxy(cfgCp *config.ConnectionPool) *reverseProxy {
transport := &http.Transport{
Proxy: http.ProxyFromEnvironment,
DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
dialer := &net.Dialer{
Timeout: 30 * time.Second,
KeepAlive: 30 * time.Second,
}
return dialer.DialContext(ctx, network, addr)
},
ForceAttemptHTTP2: true,
MaxIdleConns: cfgCp.MaxIdleConns,
MaxIdleConnsPerHost: cfgCp.MaxIdleConnsPerHost,
IdleConnTimeout: 90 * time.Second,
TLSHandshakeTimeout: 10 * time.Second,
ExpectContinueTimeout: 1 * time.Second,
}
return &reverseProxy{
rp: &httputil.ReverseProxy{
Director: func(*http.Request) {},
Transport: transport,
// Suppress error logging in ReverseProxy, since all the errors
// are handled and logged in the code below.
ErrorLog: log.NilLogger,
},
reloadSignal: make(chan struct{}),
reloadWG: sync.WaitGroup{},
maxIdleConns: cfgCp.MaxIdleConnsPerHost,
maxIdleConnsPerHost: cfgCp.MaxIdleConnsPerHost,
}
}
func (rp *reverseProxy) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
startTime := time.Now()
s, status, err := rp.getScope(req)
if err != nil {
q := getQuerySnippet(req)
err = fmt.Errorf("%q: %w; query: %q", req.RemoteAddr, err, q)
respondWith(rw, err, status)
return
}
// WARNING: don't use s.labels before s.incQueued,
// since `replica` and `cluster_node` may change inside incQueued.
if err := s.incQueued(); err != nil {
limitExcess.With(s.labels).Inc()
q := getQuerySnippet(req)
err = fmt.Errorf("%s: %w; query: %q", s, err, q)
respondWith(rw, err, http.StatusTooManyRequests)
return
}
defer s.dec()
log.Debugf("%s: request start", s)
requestSum.With(s.labels).Inc()
if s.user.allowCORS {
origin := req.Header.Get("Origin")
if len(origin) == 0 {
origin = "*"
}
rw.Header().Set("Access-Control-Allow-Origin", origin)
}
req.Body = &statReadCloser{
ReadCloser: req.Body,
bytesRead: requestBodyBytes.With(s.labels),
}
srw := &statResponseWriter{
ResponseWriter: rw,
bytesWritten: responseBodyBytes.With(s.labels),
}
req, origParams := s.decorateRequest(req)
// wrap body into cachedReadCloser, so we could obtain the original
// request on error.
req.Body = &cachedReadCloser{
ReadCloser: req.Body,
}
// publish session_id if needed
if s.sessionId != "" {
rw.Header().Set("X-ClickHouse-Server-Session-Id", s.sessionId)
}
q, shouldReturnFromCache, err := shouldRespondFromCache(s, origParams, req)
if err != nil {
respondWith(srw, err, http.StatusBadRequest)
return
}
if shouldReturnFromCache {
rp.serveFromCache(s, srw, req, origParams, q)
} else {
rp.proxyRequest(s, srw, srw, req)
}
// It is safe calling getQuerySnippet here, since the request
// has been already read in proxyRequest or serveFromCache.
query := getQuerySnippet(req)
if srw.statusCode == http.StatusOK {
requestSuccess.With(s.labels).Inc()
log.Debugf("%s: request success; query: %q; Method: %s; URL: %q", s, query, req.Method, req.URL.String())
} else {
log.Debugf("%s: request failure: non-200 status code %d; query: %q; Method: %s; URL: %q", s, srw.statusCode, query, req.Method, req.URL.String())
}
statusCodes.With(
prometheus.Labels{
"user": s.user.name,
"cluster": s.cluster.name,
"cluster_user": s.clusterUser.name,
"replica": s.host.ReplicaName(),
"cluster_node": s.host.Host(),
"code": strconv.Itoa(srw.statusCode),
},
).Inc()
since := time.Since(startTime).Seconds()
requestDuration.With(s.labels).Observe(since)
}
func shouldRespondFromCache(s *scope, origParams url.Values, req *http.Request) ([]byte, bool, error) {
if s.user.cache == nil || s.user.cache.Cache == nil {
return nil, false, nil
}
noCache := origParams.Get("no_cache")
if noCache == "1" || noCache == "true" {
return nil, false, nil
}
q, err := getFullQuery(req)
if err != nil {
return nil, false, fmt.Errorf("%s: cannot read query: %w", s, err)
}
return q, canCacheQuery(q), nil
}
func executeWithRetry(
ctx context.Context,
s *scope,
maxRetry int,
rp func(http.ResponseWriter, *http.Request),
rw ResponseWriterWithCode,
srw StatResponseWriter,
req *http.Request,
monitorDuration func(float64),
monitorRetryRequestInc func(prometheus.Labels),
) (float64, error) {
startTime := time.Now()
var since float64
// keep the request body
body, err := io.ReadAll(req.Body)
req.Body.Close()
if err != nil {
since = time.Since(startTime).Seconds()
return since, err
}
numRetry := 0
for {
// update body
req.Body = io.NopCloser(bytes.NewBuffer(body))
req.Body.Close()
rp(rw, req)
err := ctx.Err()
if err != nil {
since = time.Since(startTime).Seconds()
return since, err
}
// The request has been successfully proxied.
srw.SetStatusCode(rw.StatusCode())
// StatusBadGateway response is returned by http.ReverseProxy when
// it cannot establish connection to remote host.
if rw.StatusCode() == http.StatusBadGateway {
log.Debugf("the invalid host is: %s", s.host)
s.host.Penalize()
// comment s.host.dec() line to avoid double increment; issue #322
// s.host.dec()
s.host.SetIsActive(false)
nextHost := s.cluster.getHost()
// The query could be retried if it has no stickiness to a certain server
if numRetry < maxRetry && nextHost.IsActive() && s.sessionId == "" {
// the query execution has been failed
monitorRetryRequestInc(s.labels)
currentHost := s.host
// decrement the current failed host counter and increment the new host
// as for the end of the requests we will close the scope and in that closed scope
// decrement the new host PR - https://github.com/ContentSquare/chproxy/pull/357
if currentHost != nextHost {
currentHost.DecrementConnections()
nextHost.IncrementConnections()
}
// update host
s.host = nextHost
req.URL.Host = s.host.Host()
req.URL.Scheme = s.host.Scheme()
log.Debugf("the valid host is: %s", s.host)
} else {
since = time.Since(startTime).Seconds()
monitorDuration(since)
q := getQuerySnippet(req)
err1 := fmt.Errorf("%s: cannot reach %s; query: %q", s, s.host.Host(), q)
respondWith(srw, err1, srw.StatusCode())
break
}
} else {
since = time.Since(startTime).Seconds()
break
}
numRetry++
}
return since, nil
}
// proxyRequest proxies the given request to clickhouse and sends response
// to rw.
//
// srw is required only for setting non-200 status codes on timeouts
// or on client connection disconnects.
func (rp *reverseProxy) proxyRequest(s *scope, rw ResponseWriterWithCode, srw *statResponseWriter, req *http.Request) {
// wrap body into cachedReadCloser, so we could obtain the original
// request on error.
if _, ok := req.Body.(*cachedReadCloser); !ok {
req.Body = &cachedReadCloser{
ReadCloser: req.Body,
}
}
timeout, timeoutErrMsg := s.getTimeoutWithErrMsg()
ctx := context.Background()
if timeout > 0 {
var cancel context.CancelFunc
ctx, cancel = context.WithTimeout(ctx, timeout)
defer cancel()
}
// Cancel the ctx if client closes the remote connection,
// so the proxied query may be killed instantly.
ctx, ctxCancel := listenToCloseNotify(ctx, rw)
defer ctxCancel()
req = req.WithContext(ctx)
startTime := time.Now()
executeDuration, err := executeWithRetry(ctx, s, s.cluster.retryNumber, rp.rp.ServeHTTP, rw, srw, req, func(duration float64) {
proxiedResponseDuration.With(s.labels).Observe(duration)
}, func(labels prometheus.Labels) { retryRequest.With(labels).Inc() })
switch {
case err == nil:
return
case errors.Is(err, context.Canceled):
canceledRequest.With(s.labels).Inc()
q := getQuerySnippet(req)
log.Debugf("%s: remote client closed the connection in %s; query: %q", s, time.Since(startTime), q)
if err := s.killQuery(); err != nil {
log.Errorf("%s: cannot kill query: %s; query: %q", s, err, q)
}
srw.statusCode = 499 // See https://httpstatuses.com/499 .
case errors.Is(err, context.DeadlineExceeded):
timeoutRequest.With(s.labels).Inc()
// Penalize host with the timed out query, because it may be overloaded.
s.host.Penalize()
q := getQuerySnippet(req)
log.Debugf("%s: query timeout in %f; query: %q", s, executeDuration, q)
if err := s.killQuery(); err != nil {
log.Errorf("%s: cannot kill query: %s; query: %q", s, err, q)
}
err = fmt.Errorf("%s: %w; query: %q", s, timeoutErrMsg, q)
respondWith(rw, err, http.StatusGatewayTimeout)
srw.statusCode = http.StatusGatewayTimeout
default:
panic(fmt.Sprintf("BUG: context.Context.Err() returned unexpected error: %s", err))
}
}
func listenToCloseNotify(ctx context.Context, rw ResponseWriterWithCode) (context.Context, context.CancelFunc) {
// Cancel the ctx if client closes the remote connection,
// so the proxied query may be killed instantly.
ctx, ctxCancel := context.WithCancel(ctx)
// rw must implement http.CloseNotifier.
rwc, ok := rw.(http.CloseNotifier)
if !ok {
panic("BUG: the wrapped ResponseWriter must implement http.CloseNotifier")
}
ch := rwc.CloseNotify()
go func() {
select {
case <-ch:
ctxCancel()
case <-ctx.Done():
}
}()
return ctx, ctxCancel
}
//nolint:cyclop //TODO refactor this method, most likely requires some work.
func (rp *reverseProxy) serveFromCache(s *scope, srw *statResponseWriter, req *http.Request, origParams url.Values, q []byte) {
labels := makeCacheLabels(s)
key := newCacheKey(s, origParams, q, req)
startTime := time.Now()
userCache := s.user.cache
// Try to serve from cache
cachedData, err := userCache.Get(key)
if err == nil {
// The response has been successfully served from cache.
defer cachedData.Data.Close()
cacheHit.With(labels).Inc()
cachedResponseDuration.With(labels).Observe(time.Since(startTime).Seconds())
log.Debugf("%s: cache hit", s)
_ = RespondWithData(srw, cachedData.Data, cachedData.ContentMetadata, cachedData.Ttl, XCacheHit, http.StatusOK, labels)
return
}
// Await for potential result from concurrent query
transactionStatus, err := userCache.AwaitForConcurrentTransaction(key)
if err != nil {
// log and continue processing
log.Errorf("failed to await for concurrent transaction due to: %v", err)
} else {
if transactionStatus.State.IsCompleted() {
cachedData, err := userCache.Get(key)
if err == nil {
defer cachedData.Data.Close()
_ = RespondWithData(srw, cachedData.Data, cachedData.ContentMetadata, cachedData.Ttl, XCacheHit, http.StatusOK, labels)
cacheHitFromConcurrentQueries.With(labels).Inc()
log.Debugf("%s: cache hit after awaiting concurrent query", s)
return
} else {
cacheMissFromConcurrentQueries.With(labels).Inc()
log.Debugf("%s: cache miss after awaiting concurrent query", s)
}
} else if transactionStatus.State.IsFailed() {
respondWith(srw, fmt.Errorf(transactionStatus.FailReason), http.StatusInternalServerError)
return
}
}
// The response wasn't found in the cache.
// Request it from clickhouse.
tmpFileRespWriter, err := cache.NewTmpFileResponseWriter(srw, tmpDir)
if err != nil {
err = fmt.Errorf("%s: %w; query: %q", s, err, q)
respondWith(srw, err, http.StatusInternalServerError)
return
}
defer tmpFileRespWriter.Close()
// Initialise transaction
err = userCache.Create(key)
if err != nil {
log.Errorf("%s: %s; query: %q - failed to register transaction", s, err, q)
}
// proxy request and capture response along with headers to [[TmpFileResponseWriter]]
rp.proxyRequest(s, tmpFileRespWriter, srw, req)
contentEncoding := tmpFileRespWriter.GetCapturedContentEncoding()
contentType := tmpFileRespWriter.GetCapturedContentType()
contentLength, err := tmpFileRespWriter.GetCapturedContentLength()
if err != nil {
log.Errorf("%s: %s; query: %q - failed to get contentLength of query", s, err, q)
respondWith(srw, err, http.StatusInternalServerError)
return
}
reader, err := tmpFileRespWriter.Reader()
if err != nil {
log.Errorf("%s: %s; query: %q - failed to get Reader from tmp file", s, err, q)
respondWith(srw, err, http.StatusInternalServerError)
return
}
contentMetadata := cache.ContentMetadata{Length: contentLength, Encoding: contentEncoding, Type: contentType}
statusCode := tmpFileRespWriter.StatusCode()
if statusCode != http.StatusOK || s.canceled {
// Do not cache non-200 or cancelled responses.
// Restore the original status code by proxyRequest if it was set.
if srw.statusCode != 0 {
tmpFileRespWriter.WriteHeader(srw.statusCode)
}
errReason := "unknown error reason"
if contentLength > rp.maxErrorReasonSize {
log.Infof("%s: Error reason length (%d) is greater than max error reason size (%d)", s, contentLength, rp.maxErrorReasonSize)
} else {
errString, err := toString(reader)
if err != nil {
log.Errorf("%s failed to get error reason: %s", s, err.Error())
}
errReason = fmt.Sprintf("%s %s", failedTransactionPrefix, errString)
}
rp.completeTransaction(s, statusCode, userCache, key, q, errReason)
// we need to reset the offset since the reader of tmpFileRespWriter was already
// consumed in RespondWithData(...)
err = tmpFileRespWriter.ResetFileOffset()
if err != nil {
err = fmt.Errorf("%s: %w; query: %q", s, err, q)
respondWith(srw, err, http.StatusInternalServerError)
return
}
err = RespondWithData(srw, reader, contentMetadata, 0*time.Second, XCacheMiss, statusCode, labels)
if err != nil {
err = fmt.Errorf("%s: %w; query: %q", s, err, q)
respondWith(srw, err, http.StatusInternalServerError)
}
} else {
// Do not cache responses greater than max payload size.
if contentLength > int64(s.user.cache.MaxPayloadSize) {
cacheSkipped.With(labels).Inc()
log.Infof("%s: Request will not be cached. Content length (%d) is greater than max payload size (%d)", s, contentLength, s.user.cache.MaxPayloadSize)
rp.completeTransaction(s, statusCode, userCache, key, q, "")
err = RespondWithData(srw, reader, contentMetadata, 0*time.Second, XCacheNA, tmpFileRespWriter.StatusCode(), labels)
if err != nil {
err = fmt.Errorf("%s: %w; query: %q", s, err, q)
respondWith(srw, err, http.StatusInternalServerError)
}
return
}
cacheMiss.With(labels).Inc()
log.Debugf("%s: cache miss", s)
expiration, err := userCache.Put(reader, contentMetadata, key)
if err != nil {
cacheFailedInsert.With(labels).Inc()
log.Errorf("%s: %s; query: %q - failed to put response in the cache", s, err, q)
}
rp.completeTransaction(s, statusCode, userCache, key, q, "")
// we need to reset the offset since the reader of tmpFileRespWriter was already
// consumed in RespondWithData(...)
err = tmpFileRespWriter.ResetFileOffset()
if err != nil {
err = fmt.Errorf("%s: %w; query: %q", s, err, q)
respondWith(srw, err, http.StatusInternalServerError)
return
}
err = RespondWithData(srw, reader, contentMetadata, expiration, XCacheMiss, statusCode, labels)
if err != nil {
err = fmt.Errorf("%s: %w; query: %q", s, err, q)
respondWith(srw, err, http.StatusInternalServerError)
return
}
}
}
func makeCacheLabels(s *scope) prometheus.Labels {
// Do not store `replica` and `cluster_node` in labels, since they have
// no sense for cache metrics.
return prometheus.Labels{
"cache": s.user.cache.Name(),
"user": s.labels["user"],
"cluster": s.labels["cluster"],
"cluster_user": s.labels["cluster_user"],
}
}
func newCacheKey(s *scope, origParams url.Values, q []byte, req *http.Request) *cache.Key {
var userParamsHash uint32
if s.user.params != nil {
userParamsHash = s.user.params.key
}
queryParamsHash := calcQueryParamsHash(origParams)
credHash, err := uint32(0), error(nil)
if !s.user.cache.SharedWithAllUsers {
credHash, err = calcCredentialHash(s.clusterUser.name, s.clusterUser.password)
}
if err != nil {
log.Errorf("fail to calc hash on credentials for user %s", s.user.name)
credHash = 0
}
return cache.NewKey(
skipLeadingComments(q),
origParams,
sortHeader(req.Header.Get("Accept-Encoding")),
userParamsHash,
queryParamsHash,
credHash,
)
}
func toString(stream io.Reader) (string, error) {
buf := new(bytes.Buffer)
_, err := buf.ReadFrom(stream)
if err != nil {
return "", err
}
return bytes.NewBuffer(buf.Bytes()).String(), nil
}
// clickhouseRecoverableStatusCodes set of recoverable http responses' status codes from Clickhouse.
// When such happens we mark transaction as completed and let concurrent query to hit another Clickhouse shard.
// possible http error codes in clickhouse (i.e: https://github.com/ClickHouse/ClickHouse/blob/master/src/Server/HTTPHandler.cpp)
var clickhouseRecoverableStatusCodes = map[int]struct{}{http.StatusServiceUnavailable: {}, http.StatusRequestTimeout: {}}
func (rp *reverseProxy) completeTransaction(s *scope, statusCode int, userCache *cache.AsyncCache, key *cache.Key,
q []byte,
failReason string,
) {
// complete successful transactions or those with empty fail reason
if statusCode < 300 || failReason == "" {
if err := userCache.Complete(key); err != nil {
log.Errorf("%s: %s; query: %q", s, err, q)
}
return
}
if _, ok := clickhouseRecoverableStatusCodes[statusCode]; ok {
if err := userCache.Complete(key); err != nil {
log.Errorf("%s: %s; query: %q", s, err, q)
}
} else {
if err := userCache.Fail(key, failReason); err != nil {
log.Errorf("%s: %s; query: %q", s, err, q)
}
}
}
func calcQueryParamsHash(origParams url.Values) uint32 {
queryParams := make(map[string]string)
for param := range origParams {
if strings.HasPrefix(param, "param_") {
queryParams[param] = origParams.Get(param)
}
}
queryParamsHash, err := calcMapHash(queryParams)
if err != nil {
log.Errorf("fail to calc hash for params %s; %s", origParams, err)
return 0
}
return queryParamsHash
}
// applyConfig applies the given cfg to reverseProxy.
//
// New config is applied only if non-nil error returned.
// Otherwise old config version is kept.
func (rp *reverseProxy) applyConfig(cfg *config.Config) error {
// configLock protects from concurrent calls to applyConfig
// by serializing such calls.
// configLock shouldn't be used in other places.
rp.configLock.Lock()
defer rp.configLock.Unlock()
clusters, err := newClusters(cfg.Clusters)
if err != nil {
return err
}
rp.maxErrorReasonSize = int64(cfg.MaxErrorReasonSize)
caches := make(map[string]*cache.AsyncCache, len(cfg.Caches))
defer func() {
// caches is swapped with old caches from rp.caches
// on successful config reload - see the end of reloadConfig.
for _, tmpCache := range caches {
// Speed up applyConfig by closing caches in background,
// since the process of cache closing may be lengthy
// due to cleaning.
go tmpCache.Close()
}
}()
// transactionsTimeout used for creation of transactions registry inside async cache.
// It is set to the highest configured execution time of all users to avoid setups were users use the same cache and have configured different maxExecutionTime.
// This would provoke undesired behaviour of `dogpile effect`
transactionsTimeout := config.Duration(0)
for _, user := range cfg.Users {
if user.MaxExecutionTime > transactionsTimeout {
transactionsTimeout = user.MaxExecutionTime
}
if user.IsWildcarded {
rp.hasWildcarded = true
}
}
if err := initTempCaches(caches, transactionsTimeout, cfg.Caches); err != nil {
return err
}
params, err := paramsFromConfig(cfg.ParamGroups)
if err != nil {
return err
}
profile := &usersProfile{
cfg: cfg.Users,
clusters: clusters,
caches: caches,
params: params,
}
users, err := profile.newUsers()
if err != nil {
return err
}
if err := validateNoWildcardedUserForHeartbeat(clusters, cfg.Clusters); err != nil {
return err
}
// New configs have been successfully prepared.
// Restart service goroutines with new configs.
// Stop the previous service goroutines.
close(rp.reloadSignal)
rp.reloadWG.Wait()
rp.reloadSignal = make(chan struct{})
rp.restartWithNewConfig(caches, clusters, users)
// Substitute old configs with the new configs in rp.
// All the currently running requests will continue with old configs,
// while all the new requests will use new configs.
rp.lock.Lock()
rp.clusters = clusters
rp.users = users
// Swap is needed for deferred closing of old caches.
// See the code above where new caches are created.
caches, rp.caches = rp.caches, caches
rp.lock.Unlock()
return nil
}
func initTempCaches(caches map[string]*cache.AsyncCache, transactionsTimeout config.Duration, cfg []config.Cache) error {
for _, cc := range cfg {
if _, ok := caches[cc.Name]; ok {
return fmt.Errorf("duplicate config for cache %q", cc.Name)
}
tmpCache, err := cache.NewAsyncCache(cc, time.Duration(transactionsTimeout))
if err != nil {
return err
}
caches[cc.Name] = tmpCache
}
return nil
}
func paramsFromConfig(cfg []config.ParamGroup) (map[string]*paramsRegistry, error) {
params := make(map[string]*paramsRegistry, len(cfg))
for _, p := range cfg {
if _, ok := params[p.Name]; ok {
return nil, fmt.Errorf("duplicate config for ParamGroups %q", p.Name)
}
registry, err := newParamsRegistry(p.Params)
if err != nil {
return nil, fmt.Errorf("cannot initialize params %q: %w", p.Name, err)
}
params[p.Name] = registry
}
return params, nil
}
func validateNoWildcardedUserForHeartbeat(clusters map[string]*cluster, cfg []config.Cluster) error {
for c := range cfg {
cfgcl := cfg[c]
clname := cfgcl.Name
cuname := cfgcl.ClusterUsers[0].Name
heartbeat := cfg[c].HeartBeat
cl := clusters[clname]
cu := cl.users[cuname]
if cu.isWildcarded {
if heartbeat.Request != "/ping" && len(heartbeat.User) == 0 {
return fmt.Errorf(
"`cluster.heartbeat.user ` cannot be unset for %q because a wildcarded user cannot send heartbeat",
clname,
)
}
}
}
return nil
}
func (rp *reverseProxy) restartWithNewConfig(caches map[string]*cache.AsyncCache, clusters map[string]*cluster, users map[string]*user) {
// Reset metrics from the previous configs, which may become irrelevant
// with new configs.
// Counters and Summary metrics are always relevant.
// Gauge metrics may become irrelevant if they may freeze at non-zero
// value after config reload.
topology.HostHealth.Reset()
cacheSize.Reset()
cacheItems.Reset()
// Start service goroutines with new configs.
for _, c := range clusters {
for _, r := range c.replicas {
for _, h := range r.hosts {
rp.reloadWG.Add(1)
go func(h *topology.Node) {
h.StartHeartbeat(rp.reloadSignal)
rp.reloadWG.Done()
}(h)
}
}
for _, cu := range c.users {
rp.reloadWG.Add(1)
go func(cu *clusterUser) {
cu.rateLimiter.run(rp.reloadSignal)
rp.reloadWG.Done()
}(cu)
}
}
for _, u := range users {
rp.reloadWG.Add(1)
go func(u *user) {
u.rateLimiter.run(rp.reloadSignal)
rp.reloadWG.Done()
}(u)
}
}
// refreshCacheMetrics refreshes cacheSize and cacheItems metrics.
func (rp *reverseProxy) refreshCacheMetrics() {
rp.lock.RLock()
defer rp.lock.RUnlock()
for _, c := range rp.caches {
stats := c.Stats()
labels := prometheus.Labels{
"cache": c.Name(),
}
cacheSize.With(labels).Set(float64(stats.Size))
cacheItems.With(labels).Set(float64(stats.Items))
}
}
// find user, cluster and clusterUser
// in case of wildcarded user, cluster user is crafted to use original credentials
func (rp *reverseProxy) getUser(name string, password string) (found bool, u *user, c *cluster, cu *clusterUser) {
rp.lock.RLock()
defer rp.lock.RUnlock()
found = false
u = rp.users[name]
switch {
case u != nil:
found = (u.password == password)
// existence of c and cu for toCluster is guaranteed by applyConfig
c = rp.clusters[u.toCluster]
cu = c.users[u.toUser]
case name == "" || name == defaultUser:
// default user can't work with the wildcarded feature for security reasons
found = false
case rp.hasWildcarded:
// checking if we have wildcarded users and if username matches one 3 possibles patterns
found, u, c, cu = rp.findWildcardedUserInformation(name, password)
}
return found, u, c, cu
}
func (rp *reverseProxy) findWildcardedUserInformation(name string, password string) (found bool, u *user, c *cluster, cu *clusterUser) {
// cf a validation in config.go, the names must contains either a prefix, a suffix or a wildcard
// the wildcarded user is "*"
// the wildcarded user is "*[suffix]"
// the wildcarded user is "[prefix]*"
for _, user := range rp.users {
if user.isWildcarded {
s := strings.Split(user.name, "*")
switch {
case s[0] == "" && s[1] == "":
return rp.generateWildcardedUserInformation(user, name, password)
case s[0] == "":
suffix := s[1]
if strings.HasSuffix(name, suffix) {
return rp.generateWildcardedUserInformation(user, name, password)
}
case s[1] == "":
prefix := s[0]
if strings.HasPrefix(name, prefix) {
return rp.generateWildcardedUserInformation(user, name, password)
}
}
}
}
return false, nil, nil, nil
}
func (rp *reverseProxy) generateWildcardedUserInformation(user *user, name string, password string) (found bool, u *user, c *cluster, cu *clusterUser) {
found = false
c = rp.clusters[user.toCluster]
wildcardedCu := c.users[user.toUser]
if wildcardedCu != nil {
newCU := deepCopy(wildcardedCu)
found = true
u = user
cu = newCU
cu.name = name
cu.password = password
// TODO : improve the following behavior
// the wildcarded user feature creates some side-effects on clusterUser limitations (like the max_concurrent_queries)
// because of the use of a deep copy of the clusterUser. The side effect should not be too impactful since the limitation still works on user.
// But we need this deep copy since we're changing the name & password of clusterUser and if we used the same instance for every call to chproxy,
// it could lead to security issues since a specific query run by user A on chproxy side could trigger a query in clickhouse from user B.
// Doing a clean fix would require a huge refactoring.
}
return
}
func (rp *reverseProxy) getScope(req *http.Request) (*scope, int, error) {
name, password := getAuth(req)
sessionId := getSessionId(req)
sessionTimeout := getSessionTimeout(req)
var (
u *user
c *cluster
cu *clusterUser
)
found, u, c, cu := rp.getUser(name, password)
if !found {
return nil, http.StatusUnauthorized, fmt.Errorf("invalid username or password for user %q", name)
}
if u.denyHTTP && req.TLS == nil {
return nil, http.StatusForbidden, fmt.Errorf("user %q is not allowed to access via http", u.name)
}
if u.denyHTTPS && req.TLS != nil {
return nil, http.StatusForbidden, fmt.Errorf("user %q is not allowed to access via https", u.name)
}
if !u.allowedNetworks.Contains(req.RemoteAddr) {
return nil, http.StatusForbidden, fmt.Errorf("user %q is not allowed to access", u.name)
}
if !cu.allowedNetworks.Contains(req.RemoteAddr) {
return nil, http.StatusForbidden, fmt.Errorf("cluster user %q is not allowed to access", cu.name)
}
s := newScope(req, u, c, cu, sessionId, sessionTimeout)
q, err := getFullQuery(req)
if err != nil {
return nil, http.StatusBadRequest, fmt.Errorf("%s: cannot read query: %w", s, err)
}
s.requestPacketSize = len(q)
return s, 0, nil
}