[VOL-2235] Mocks and interfaces for rw-core
This update consists of mocks that are used by the rw-core
during unit testing. It also includes interfaces used for unit
tests.
Change-Id: I20ca1455c358113c3aa897acc6355e0ddbc614b7
diff --git a/vendor/go.etcd.io/etcd/client/client.go b/vendor/go.etcd.io/etcd/client/client.go
new file mode 100644
index 0000000..de9ab79
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/client/client.go
@@ -0,0 +1,710 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package client
+
+import (
+ "context"
+ "encoding/json"
+ "errors"
+ "fmt"
+ "io/ioutil"
+ "math/rand"
+ "net"
+ "net/http"
+ "net/url"
+ "sort"
+ "strconv"
+ "sync"
+ "time"
+
+ "go.etcd.io/etcd/version"
+)
+
+var (
+ ErrNoEndpoints = errors.New("client: no endpoints available")
+ ErrTooManyRedirects = errors.New("client: too many redirects")
+ ErrClusterUnavailable = errors.New("client: etcd cluster is unavailable or misconfigured")
+ ErrNoLeaderEndpoint = errors.New("client: no leader endpoint available")
+ errTooManyRedirectChecks = errors.New("client: too many redirect checks")
+
+ // oneShotCtxValue is set on a context using WithValue(&oneShotValue) so
+ // that Do() will not retry a request
+ oneShotCtxValue interface{}
+)
+
+var DefaultRequestTimeout = 5 * time.Second
+
+var DefaultTransport CancelableTransport = &http.Transport{
+ Proxy: http.ProxyFromEnvironment,
+ Dial: (&net.Dialer{
+ Timeout: 30 * time.Second,
+ KeepAlive: 30 * time.Second,
+ }).Dial,
+ TLSHandshakeTimeout: 10 * time.Second,
+}
+
+type EndpointSelectionMode int
+
+const (
+ // EndpointSelectionRandom is the default value of the 'SelectionMode'.
+ // As the name implies, the client object will pick a node from the members
+ // of the cluster in a random fashion. If the cluster has three members, A, B,
+ // and C, the client picks any node from its three members as its request
+ // destination.
+ EndpointSelectionRandom EndpointSelectionMode = iota
+
+ // If 'SelectionMode' is set to 'EndpointSelectionPrioritizeLeader',
+ // requests are sent directly to the cluster leader. This reduces
+ // forwarding roundtrips compared to making requests to etcd followers
+ // who then forward them to the cluster leader. In the event of a leader
+ // failure, however, clients configured this way cannot prioritize among
+ // the remaining etcd followers. Therefore, when a client sets 'SelectionMode'
+ // to 'EndpointSelectionPrioritizeLeader', it must use 'client.AutoSync()' to
+ // maintain its knowledge of current cluster state.
+ //
+ // This mode should be used with Client.AutoSync().
+ EndpointSelectionPrioritizeLeader
+)
+
+type Config struct {
+ // Endpoints defines a set of URLs (schemes, hosts and ports only)
+ // that can be used to communicate with a logical etcd cluster. For
+ // example, a three-node cluster could be provided like so:
+ //
+ // Endpoints: []string{
+ // "http://node1.example.com:2379",
+ // "http://node2.example.com:2379",
+ // "http://node3.example.com:2379",
+ // }
+ //
+ // If multiple endpoints are provided, the Client will attempt to
+ // use them all in the event that one or more of them are unusable.
+ //
+ // If Client.Sync is ever called, the Client may cache an alternate
+ // set of endpoints to continue operation.
+ Endpoints []string
+
+ // Transport is used by the Client to drive HTTP requests. If not
+ // provided, DefaultTransport will be used.
+ Transport CancelableTransport
+
+ // CheckRedirect specifies the policy for handling HTTP redirects.
+ // If CheckRedirect is not nil, the Client calls it before
+ // following an HTTP redirect. The sole argument is the number of
+ // requests that have already been made. If CheckRedirect returns
+ // an error, Client.Do will not make any further requests and return
+ // the error back it to the caller.
+ //
+ // If CheckRedirect is nil, the Client uses its default policy,
+ // which is to stop after 10 consecutive requests.
+ CheckRedirect CheckRedirectFunc
+
+ // Username specifies the user credential to add as an authorization header
+ Username string
+
+ // Password is the password for the specified user to add as an authorization header
+ // to the request.
+ Password string
+
+ // HeaderTimeoutPerRequest specifies the time limit to wait for response
+ // header in a single request made by the Client. The timeout includes
+ // connection time, any redirects, and header wait time.
+ //
+ // For non-watch GET request, server returns the response body immediately.
+ // For PUT/POST/DELETE request, server will attempt to commit request
+ // before responding, which is expected to take `100ms + 2 * RTT`.
+ // For watch request, server returns the header immediately to notify Client
+ // watch start. But if server is behind some kind of proxy, the response
+ // header may be cached at proxy, and Client cannot rely on this behavior.
+ //
+ // Especially, wait request will ignore this timeout.
+ //
+ // One API call may send multiple requests to different etcd servers until it
+ // succeeds. Use context of the API to specify the overall timeout.
+ //
+ // A HeaderTimeoutPerRequest of zero means no timeout.
+ HeaderTimeoutPerRequest time.Duration
+
+ // SelectionMode is an EndpointSelectionMode enum that specifies the
+ // policy for choosing the etcd cluster node to which requests are sent.
+ SelectionMode EndpointSelectionMode
+}
+
+func (cfg *Config) transport() CancelableTransport {
+ if cfg.Transport == nil {
+ return DefaultTransport
+ }
+ return cfg.Transport
+}
+
+func (cfg *Config) checkRedirect() CheckRedirectFunc {
+ if cfg.CheckRedirect == nil {
+ return DefaultCheckRedirect
+ }
+ return cfg.CheckRedirect
+}
+
+// CancelableTransport mimics net/http.Transport, but requires that
+// the object also support request cancellation.
+type CancelableTransport interface {
+ http.RoundTripper
+ CancelRequest(req *http.Request)
+}
+
+type CheckRedirectFunc func(via int) error
+
+// DefaultCheckRedirect follows up to 10 redirects, but no more.
+var DefaultCheckRedirect CheckRedirectFunc = func(via int) error {
+ if via > 10 {
+ return ErrTooManyRedirects
+ }
+ return nil
+}
+
+type Client interface {
+ // Sync updates the internal cache of the etcd cluster's membership.
+ Sync(context.Context) error
+
+ // AutoSync periodically calls Sync() every given interval.
+ // The recommended sync interval is 10 seconds to 1 minute, which does
+ // not bring too much overhead to server and makes client catch up the
+ // cluster change in time.
+ //
+ // The example to use it:
+ //
+ // for {
+ // err := client.AutoSync(ctx, 10*time.Second)
+ // if err == context.DeadlineExceeded || err == context.Canceled {
+ // break
+ // }
+ // log.Print(err)
+ // }
+ AutoSync(context.Context, time.Duration) error
+
+ // Endpoints returns a copy of the current set of API endpoints used
+ // by Client to resolve HTTP requests. If Sync has ever been called,
+ // this may differ from the initial Endpoints provided in the Config.
+ Endpoints() []string
+
+ // SetEndpoints sets the set of API endpoints used by Client to resolve
+ // HTTP requests. If the given endpoints are not valid, an error will be
+ // returned
+ SetEndpoints(eps []string) error
+
+ // GetVersion retrieves the current etcd server and cluster version
+ GetVersion(ctx context.Context) (*version.Versions, error)
+
+ httpClient
+}
+
+func New(cfg Config) (Client, error) {
+ c := &httpClusterClient{
+ clientFactory: newHTTPClientFactory(cfg.transport(), cfg.checkRedirect(), cfg.HeaderTimeoutPerRequest),
+ rand: rand.New(rand.NewSource(int64(time.Now().Nanosecond()))),
+ selectionMode: cfg.SelectionMode,
+ }
+ if cfg.Username != "" {
+ c.credentials = &credentials{
+ username: cfg.Username,
+ password: cfg.Password,
+ }
+ }
+ if err := c.SetEndpoints(cfg.Endpoints); err != nil {
+ return nil, err
+ }
+ return c, nil
+}
+
+type httpClient interface {
+ Do(context.Context, httpAction) (*http.Response, []byte, error)
+}
+
+func newHTTPClientFactory(tr CancelableTransport, cr CheckRedirectFunc, headerTimeout time.Duration) httpClientFactory {
+ return func(ep url.URL) httpClient {
+ return &redirectFollowingHTTPClient{
+ checkRedirect: cr,
+ client: &simpleHTTPClient{
+ transport: tr,
+ endpoint: ep,
+ headerTimeout: headerTimeout,
+ },
+ }
+ }
+}
+
+type credentials struct {
+ username string
+ password string
+}
+
+type httpClientFactory func(url.URL) httpClient
+
+type httpAction interface {
+ HTTPRequest(url.URL) *http.Request
+}
+
+type httpClusterClient struct {
+ clientFactory httpClientFactory
+ endpoints []url.URL
+ pinned int
+ credentials *credentials
+ sync.RWMutex
+ rand *rand.Rand
+ selectionMode EndpointSelectionMode
+}
+
+func (c *httpClusterClient) getLeaderEndpoint(ctx context.Context, eps []url.URL) (string, error) {
+ ceps := make([]url.URL, len(eps))
+ copy(ceps, eps)
+
+ // To perform a lookup on the new endpoint list without using the current
+ // client, we'll copy it
+ clientCopy := &httpClusterClient{
+ clientFactory: c.clientFactory,
+ credentials: c.credentials,
+ rand: c.rand,
+
+ pinned: 0,
+ endpoints: ceps,
+ }
+
+ mAPI := NewMembersAPI(clientCopy)
+ leader, err := mAPI.Leader(ctx)
+ if err != nil {
+ return "", err
+ }
+ if len(leader.ClientURLs) == 0 {
+ return "", ErrNoLeaderEndpoint
+ }
+
+ return leader.ClientURLs[0], nil // TODO: how to handle multiple client URLs?
+}
+
+func (c *httpClusterClient) parseEndpoints(eps []string) ([]url.URL, error) {
+ if len(eps) == 0 {
+ return []url.URL{}, ErrNoEndpoints
+ }
+
+ neps := make([]url.URL, len(eps))
+ for i, ep := range eps {
+ u, err := url.Parse(ep)
+ if err != nil {
+ return []url.URL{}, err
+ }
+ neps[i] = *u
+ }
+ return neps, nil
+}
+
+func (c *httpClusterClient) SetEndpoints(eps []string) error {
+ neps, err := c.parseEndpoints(eps)
+ if err != nil {
+ return err
+ }
+
+ c.Lock()
+ defer c.Unlock()
+
+ c.endpoints = shuffleEndpoints(c.rand, neps)
+ // We're not doing anything for PrioritizeLeader here. This is
+ // due to not having a context meaning we can't call getLeaderEndpoint
+ // However, if you're using PrioritizeLeader, you've already been told
+ // to regularly call sync, where we do have a ctx, and can figure the
+ // leader. PrioritizeLeader is also quite a loose guarantee, so deal
+ // with it
+ c.pinned = 0
+
+ return nil
+}
+
+func (c *httpClusterClient) Do(ctx context.Context, act httpAction) (*http.Response, []byte, error) {
+ action := act
+ c.RLock()
+ leps := len(c.endpoints)
+ eps := make([]url.URL, leps)
+ n := copy(eps, c.endpoints)
+ pinned := c.pinned
+
+ if c.credentials != nil {
+ action = &authedAction{
+ act: act,
+ credentials: *c.credentials,
+ }
+ }
+ c.RUnlock()
+
+ if leps == 0 {
+ return nil, nil, ErrNoEndpoints
+ }
+
+ if leps != n {
+ return nil, nil, errors.New("unable to pick endpoint: copy failed")
+ }
+
+ var resp *http.Response
+ var body []byte
+ var err error
+ cerr := &ClusterError{}
+ isOneShot := ctx.Value(&oneShotCtxValue) != nil
+
+ for i := pinned; i < leps+pinned; i++ {
+ k := i % leps
+ hc := c.clientFactory(eps[k])
+ resp, body, err = hc.Do(ctx, action)
+ if err != nil {
+ cerr.Errors = append(cerr.Errors, err)
+ if err == ctx.Err() {
+ return nil, nil, ctx.Err()
+ }
+ if err == context.Canceled || err == context.DeadlineExceeded {
+ return nil, nil, err
+ }
+ } else if resp.StatusCode/100 == 5 {
+ switch resp.StatusCode {
+ case http.StatusInternalServerError, http.StatusServiceUnavailable:
+ // TODO: make sure this is a no leader response
+ cerr.Errors = append(cerr.Errors, fmt.Errorf("client: etcd member %s has no leader", eps[k].String()))
+ default:
+ cerr.Errors = append(cerr.Errors, fmt.Errorf("client: etcd member %s returns server error [%s]", eps[k].String(), http.StatusText(resp.StatusCode)))
+ }
+ err = cerr.Errors[0]
+ }
+ if err != nil {
+ if !isOneShot {
+ continue
+ }
+ c.Lock()
+ c.pinned = (k + 1) % leps
+ c.Unlock()
+ return nil, nil, err
+ }
+ if k != pinned {
+ c.Lock()
+ c.pinned = k
+ c.Unlock()
+ }
+ return resp, body, nil
+ }
+
+ return nil, nil, cerr
+}
+
+func (c *httpClusterClient) Endpoints() []string {
+ c.RLock()
+ defer c.RUnlock()
+
+ eps := make([]string, len(c.endpoints))
+ for i, ep := range c.endpoints {
+ eps[i] = ep.String()
+ }
+
+ return eps
+}
+
+func (c *httpClusterClient) Sync(ctx context.Context) error {
+ mAPI := NewMembersAPI(c)
+ ms, err := mAPI.List(ctx)
+ if err != nil {
+ return err
+ }
+
+ var eps []string
+ for _, m := range ms {
+ eps = append(eps, m.ClientURLs...)
+ }
+
+ neps, err := c.parseEndpoints(eps)
+ if err != nil {
+ return err
+ }
+
+ npin := 0
+
+ switch c.selectionMode {
+ case EndpointSelectionRandom:
+ c.RLock()
+ eq := endpointsEqual(c.endpoints, neps)
+ c.RUnlock()
+
+ if eq {
+ return nil
+ }
+ // When items in the endpoint list changes, we choose a new pin
+ neps = shuffleEndpoints(c.rand, neps)
+ case EndpointSelectionPrioritizeLeader:
+ nle, err := c.getLeaderEndpoint(ctx, neps)
+ if err != nil {
+ return ErrNoLeaderEndpoint
+ }
+
+ for i, n := range neps {
+ if n.String() == nle {
+ npin = i
+ break
+ }
+ }
+ default:
+ return fmt.Errorf("invalid endpoint selection mode: %d", c.selectionMode)
+ }
+
+ c.Lock()
+ defer c.Unlock()
+ c.endpoints = neps
+ c.pinned = npin
+
+ return nil
+}
+
+func (c *httpClusterClient) AutoSync(ctx context.Context, interval time.Duration) error {
+ ticker := time.NewTicker(interval)
+ defer ticker.Stop()
+ for {
+ err := c.Sync(ctx)
+ if err != nil {
+ return err
+ }
+ select {
+ case <-ctx.Done():
+ return ctx.Err()
+ case <-ticker.C:
+ }
+ }
+}
+
+func (c *httpClusterClient) GetVersion(ctx context.Context) (*version.Versions, error) {
+ act := &getAction{Prefix: "/version"}
+
+ resp, body, err := c.Do(ctx, act)
+ if err != nil {
+ return nil, err
+ }
+
+ switch resp.StatusCode {
+ case http.StatusOK:
+ if len(body) == 0 {
+ return nil, ErrEmptyBody
+ }
+ var vresp version.Versions
+ if err := json.Unmarshal(body, &vresp); err != nil {
+ return nil, ErrInvalidJSON
+ }
+ return &vresp, nil
+ default:
+ var etcdErr Error
+ if err := json.Unmarshal(body, &etcdErr); err != nil {
+ return nil, ErrInvalidJSON
+ }
+ return nil, etcdErr
+ }
+}
+
+type roundTripResponse struct {
+ resp *http.Response
+ err error
+}
+
+type simpleHTTPClient struct {
+ transport CancelableTransport
+ endpoint url.URL
+ headerTimeout time.Duration
+}
+
+func (c *simpleHTTPClient) Do(ctx context.Context, act httpAction) (*http.Response, []byte, error) {
+ req := act.HTTPRequest(c.endpoint)
+
+ if err := printcURL(req); err != nil {
+ return nil, nil, err
+ }
+
+ isWait := false
+ if req != nil && req.URL != nil {
+ ws := req.URL.Query().Get("wait")
+ if len(ws) != 0 {
+ var err error
+ isWait, err = strconv.ParseBool(ws)
+ if err != nil {
+ return nil, nil, fmt.Errorf("wrong wait value %s (%v for %+v)", ws, err, req)
+ }
+ }
+ }
+
+ var hctx context.Context
+ var hcancel context.CancelFunc
+ if !isWait && c.headerTimeout > 0 {
+ hctx, hcancel = context.WithTimeout(ctx, c.headerTimeout)
+ } else {
+ hctx, hcancel = context.WithCancel(ctx)
+ }
+ defer hcancel()
+
+ reqcancel := requestCanceler(c.transport, req)
+
+ rtchan := make(chan roundTripResponse, 1)
+ go func() {
+ resp, err := c.transport.RoundTrip(req)
+ rtchan <- roundTripResponse{resp: resp, err: err}
+ close(rtchan)
+ }()
+
+ var resp *http.Response
+ var err error
+
+ select {
+ case rtresp := <-rtchan:
+ resp, err = rtresp.resp, rtresp.err
+ case <-hctx.Done():
+ // cancel and wait for request to actually exit before continuing
+ reqcancel()
+ rtresp := <-rtchan
+ resp = rtresp.resp
+ switch {
+ case ctx.Err() != nil:
+ err = ctx.Err()
+ case hctx.Err() != nil:
+ err = fmt.Errorf("client: endpoint %s exceeded header timeout", c.endpoint.String())
+ default:
+ panic("failed to get error from context")
+ }
+ }
+
+ // always check for resp nil-ness to deal with possible
+ // race conditions between channels above
+ defer func() {
+ if resp != nil {
+ resp.Body.Close()
+ }
+ }()
+
+ if err != nil {
+ return nil, nil, err
+ }
+
+ var body []byte
+ done := make(chan struct{})
+ go func() {
+ body, err = ioutil.ReadAll(resp.Body)
+ done <- struct{}{}
+ }()
+
+ select {
+ case <-ctx.Done():
+ resp.Body.Close()
+ <-done
+ return nil, nil, ctx.Err()
+ case <-done:
+ }
+
+ return resp, body, err
+}
+
+type authedAction struct {
+ act httpAction
+ credentials credentials
+}
+
+func (a *authedAction) HTTPRequest(url url.URL) *http.Request {
+ r := a.act.HTTPRequest(url)
+ r.SetBasicAuth(a.credentials.username, a.credentials.password)
+ return r
+}
+
+type redirectFollowingHTTPClient struct {
+ client httpClient
+ checkRedirect CheckRedirectFunc
+}
+
+func (r *redirectFollowingHTTPClient) Do(ctx context.Context, act httpAction) (*http.Response, []byte, error) {
+ next := act
+ for i := 0; i < 100; i++ {
+ if i > 0 {
+ if err := r.checkRedirect(i); err != nil {
+ return nil, nil, err
+ }
+ }
+ resp, body, err := r.client.Do(ctx, next)
+ if err != nil {
+ return nil, nil, err
+ }
+ if resp.StatusCode/100 == 3 {
+ hdr := resp.Header.Get("Location")
+ if hdr == "" {
+ return nil, nil, fmt.Errorf("location header not set")
+ }
+ loc, err := url.Parse(hdr)
+ if err != nil {
+ return nil, nil, fmt.Errorf("location header not valid URL: %s", hdr)
+ }
+ next = &redirectedHTTPAction{
+ action: act,
+ location: *loc,
+ }
+ continue
+ }
+ return resp, body, nil
+ }
+
+ return nil, nil, errTooManyRedirectChecks
+}
+
+type redirectedHTTPAction struct {
+ action httpAction
+ location url.URL
+}
+
+func (r *redirectedHTTPAction) HTTPRequest(ep url.URL) *http.Request {
+ orig := r.action.HTTPRequest(ep)
+ orig.URL = &r.location
+ return orig
+}
+
+func shuffleEndpoints(r *rand.Rand, eps []url.URL) []url.URL {
+ // copied from Go 1.9<= rand.Rand.Perm
+ n := len(eps)
+ p := make([]int, n)
+ for i := 0; i < n; i++ {
+ j := r.Intn(i + 1)
+ p[i] = p[j]
+ p[j] = i
+ }
+ neps := make([]url.URL, n)
+ for i, k := range p {
+ neps[i] = eps[k]
+ }
+ return neps
+}
+
+func endpointsEqual(left, right []url.URL) bool {
+ if len(left) != len(right) {
+ return false
+ }
+
+ sLeft := make([]string, len(left))
+ sRight := make([]string, len(right))
+ for i, l := range left {
+ sLeft[i] = l.String()
+ }
+ for i, r := range right {
+ sRight[i] = r.String()
+ }
+
+ sort.Strings(sLeft)
+ sort.Strings(sRight)
+ for i := range sLeft {
+ if sLeft[i] != sRight[i] {
+ return false
+ }
+ }
+ return true
+}