func (c *Client) do(ctx context.Context, req *http.Request) (*http.Response, error) {
if nil == ctx || nil == ctx.Done() { // ctx.Done() is for ctx
return c.Client.Do(req)
}
var resc = make(chan *http.Response, 1)
var errc = make(chan error, 1)
// Perform request from separate routine.
go func() {
res, err := c.Client.Do(req)
if err != nil {
errc <- err
} else {
resc <- res
}
}()
// Wait for request completion of context expiry.
select {
case <-ctx.Done():
c.t.CancelRequest(req)
return nil, ctx.Err()
case err := <-errc:
return nil, err
case res := <-resc:
return res, nil
}
}
func paintLines(ctx context.Context, r io.Reader, source string) {
scanner := bufio.NewScanner(r)
doneC := ctx.Done()
for scanner.Scan() {
lsp.Println(source, scanner.Text())
select {
case <-doneC:
break
default:
// do nothing
}
}
if err := ctx.Err(); err != nil {
errC <- err
return
}
if err := scanner.Err(); err != nil {
errC <- err
return
}
errC <- nil
}
// WaitForResult wraps govmomi operations and wait the operation to complete.
// Return the operation result
// Sample usage:
// info, err := WaitForResult(ctx, func(ctx) (*TaskInfo, error) {
// return vm, vm.Reconfigure(ctx, config)
// })
func WaitForResult(ctx context.Context, f func(context.Context) (Task, error)) (*types.TaskInfo, error) {
var err error
var info *types.TaskInfo
var backoffFactor int64 = 1
for {
var t Task
if t, err = f(ctx); err == nil {
info, err = t.WaitForResult(ctx, nil)
if err == nil {
return info, err
}
}
if !isTaskInProgress(err) {
return info, err
}
sleepValue := time.Duration(backoffFactor * (rand.Int63n(100) + int64(50)))
select {
case <-time.After(sleepValue * time.Millisecond):
backoffFactor *= 2
if backoffFactor > maxBackoffFactor {
backoffFactor = maxBackoffFactor
}
case <-ctx.Done():
return info, ctx.Err()
}
log.Warnf("retrying task")
}
}
func cgoLookupPTR(ctx context.Context, addr string) (names []string, err error, completed bool) {
var zone string
ip := parseIPv4(addr)
if ip == nil {
ip, zone = parseIPv6(addr, true)
}
if ip == nil {
return nil, &DNSError{Err: "invalid address", Name: addr}, true
}
sa, salen := cgoSockaddr(ip, zone)
if sa == nil {
return nil, &DNSError{Err: "invalid address " + ip.String(), Name: addr}, true
}
if ctx.Done() == nil {
names, err := cgoLookupAddrPTR(addr, sa, salen)
return names, err, true
}
result := make(chan reverseLookupResult, 1)
go cgoReverseLookup(result, addr, sa, salen)
select {
case r := <-result:
return r.names, r.err, true
case <-ctx.Done():
return nil, mapErr(ctx.Err()), false
}
}
func dialPlan9(ctx context.Context, net string, laddr, raddr Addr) (fd *netFD, err error) {
defer func() { fixErr(err) }()
type res struct {
fd *netFD
err error
}
resc := make(chan res)
go func() {
testHookDialChannel()
fd, err := dialPlan9Blocking(ctx, net, laddr, raddr)
select {
case resc <- res{fd, err}:
case <-ctx.Done():
if fd != nil {
fd.Close()
}
}
}()
select {
case res := <-resc:
return res.fd, res.err
case <-ctx.Done():
return nil, mapErr(ctx.Err())
}
}
// ScanFiles takes a chanel of files
func ScanFilesToBytes(ctx context.Context, in chan File) chan Content {
out := make(chan Content)
go func() {
defer close(out)
for {
select {
case value, open := <-in:
if !open {
return
}
if value.Err != nil {
out <- Content{"", nil, kerr.Wrap("PQUCOUYLJE", value.Err)}
return
}
bytes, err := ProcessFile(value.File)
// process returns Bytes == nil for non json files, so we should skip them
if bytes != nil || err != nil {
out <- Content{value.File, bytes, err}
}
case <-ctx.Done():
out <- Content{"", nil, kerr.Wrap("AFBJCTFOKX", ctx.Err())}
return
}
}
}()
return out
}
func ctxDriverBegin(ctx context.Context, ci driver.Conn) (driver.Tx, error) {
if ciCtx, is := ci.(driver.ConnBeginContext); is {
return ciCtx.BeginContext(ctx)
}
if ctx.Done() == context.Background().Done() {
return ci.Begin()
}
// Check the transaction level in ctx. If set and non-default
// then return an error here as the BeginContext driver value is not supported.
if level, ok := driver.IsolationFromContext(ctx); ok && level != driver.IsolationLevel(LevelDefault) {
return nil, errors.New("sql: driver does not support non-default isolation level")
}
// Check for a read-only parameter in ctx. If a read-only transaction is
// requested return an error as the BeginContext driver value is not supported.
if ro := driver.ReadOnlyFromContext(ctx); ro {
return nil, errors.New("sql: driver does not support read-only transactions")
}
txi, err := ci.Begin()
if err == nil {
select {
default:
case <-ctx.Done():
txi.Rollback()
return nil, ctx.Err()
}
}
return txi, err
}
func (s *subscriber) Loop(ctx context.Context, q Queue) error {
var (
opened bool = true
m *protocol.Message
)
sCtx, cancel := context.WithCancel(ctx)
s.cancel = cancel
defer func() { s.cancel = nil }()
for opened {
select {
case m, opened = <-s.route.MessagesChannel():
if !opened {
break
}
q.Push(NewRequest(s, m))
case <-sCtx.Done():
// If the parent context is still running then only this subscriber context
// has been cancelled
if ctx.Err() == nil {
return sCtx.Err()
}
return nil
}
}
//TODO Cosmin Bogdan returning this error can mean 2 things: overflow of route's channel, or intentional stopping of router / gubled.
return ErrRouteChannelClosed
}
// Update replace an item by a new one in the mongo collection
func (m *Handler) Update(ctx context.Context, item *resource.Item, original *resource.Item) error {
mItem := newMongoItem(item)
c, err := m.c(ctx)
if err != nil {
return err
}
defer m.close(c)
err = c.Update(bson.M{"_id": original.ID, "_etag": original.ETag}, mItem)
if err == mgo.ErrNotFound {
// Determine if the item is not found or if the item is found but etag missmatch
var count int
count, err = c.FindId(original.ID).Count()
if err != nil {
// The find returned an unexpected err, just forward it with no mapping
} else if count == 0 {
err = resource.ErrNotFound
} else if ctx.Err() != nil {
err = ctx.Err()
} else {
// If the item were found, it means that its etag didn't match
err = resource.ErrConflict
}
}
return err
}
// lookupProtocol looks up IP protocol name and returns correspondent protocol number.
func lookupProtocol(ctx context.Context, name string) (int, error) {
// GetProtoByName return value is stored in thread local storage.
// Start new os thread before the call to prevent races.
type result struct {
proto int
err error
}
ch := make(chan result) // unbuffered
go func() {
acquireThread()
defer releaseThread()
runtime.LockOSThread()
defer runtime.UnlockOSThread()
proto, err := getprotobyname(name)
select {
case ch <- result{proto: proto, err: err}:
case <-ctx.Done():
}
}()
select {
case r := <-ch:
if r.err != nil {
if proto, err := lookupProtocolMap(name); err == nil {
return proto, nil
}
r.err = &DNSError{Err: r.err.Error(), Name: name}
}
return r.proto, r.err
case <-ctx.Done():
return 0, mapErr(ctx.Err())
}
}
func (ds *dagService) GetMany(ctx context.Context, keys []*cid.Cid) <-chan *NodeOption {
out := make(chan *NodeOption, len(keys))
blocks := ds.Blocks.GetBlocks(ctx, keys)
var count int
go func() {
defer close(out)
for {
select {
case b, ok := <-blocks:
if !ok {
if count != len(keys) {
out <- &NodeOption{Err: fmt.Errorf("failed to fetch all nodes")}
}
return
}
nd, err := decodeBlock(b)
if err != nil {
out <- &NodeOption{Err: err}
return
}
out <- &NodeOption{Node: nd}
count++
case <-ctx.Done():
out <- &NodeOption{Err: ctx.Err()}
return
}
}
}()
return out
}
func (e *apiClient) PerformRequests(ctx context.Context, queries []QueryToSend) (*tsdb.QueryResult, error) {
queryResult := &tsdb.QueryResult{}
queryCount := len(queries)
jobsChan := make(chan QueryToSend, queryCount)
resultChan := make(chan []*tsdb.TimeSeries, queryCount)
errorsChan := make(chan error, 1)
for w := 1; w <= MaxWorker; w++ {
go e.spawnWorker(ctx, w, jobsChan, resultChan, errorsChan)
}
for _, v := range queries {
jobsChan <- v
}
close(jobsChan)
resultCounter := 0
for {
select {
case timeseries := <-resultChan:
queryResult.Series = append(queryResult.Series, timeseries...)
resultCounter++
if resultCounter == queryCount {
close(resultChan)
return queryResult, nil
}
case err := <-errorsChan:
return nil, err
case <-ctx.Done():
return nil, ctx.Err()
}
}
}
func EnumerateChildrenAsync(ctx context.Context, ds DAGService, c *cid.Cid, visit func(*cid.Cid) bool) error {
toprocess := make(chan []*cid.Cid, 8)
nodes := make(chan *NodeOption, 8)
ctx, cancel := context.WithCancel(ctx)
defer cancel()
defer close(toprocess)
go fetchNodes(ctx, ds, toprocess, nodes)
root, err := ds.Get(ctx, c)
if err != nil {
return err
}
nodes <- &NodeOption{Node: root}
live := 1
for {
select {
case opt, ok := <-nodes:
if !ok {
return nil
}
if opt.Err != nil {
return opt.Err
}
nd := opt.Node
// a node has been fetched
live--
var cids []*cid.Cid
for _, lnk := range nd.Links() {
c := lnk.Cid
if visit(c) {
live++
cids = append(cids, c)
}
}
if live == 0 {
return nil
}
if len(cids) > 0 {
select {
case toprocess <- cids:
case <-ctx.Done():
return ctx.Err()
}
}
case <-ctx.Done():
return ctx.Err()
}
}
}
// PopulateShard gets data for predicate pred from server with id serverId and
// writes it to RocksDB.
func populateShard(ctx context.Context, pl *pool, group uint32) (int, error) {
gkeys, err := generateGroup(group)
if err != nil {
return 0, x.Wrapf(err, "While generating keys group")
}
conn, err := pl.Get()
if err != nil {
return 0, err
}
defer pl.Put(conn)
c := NewWorkerClient(conn)
stream, err := c.PredicateData(context.Background(), gkeys)
if err != nil {
return 0, err
}
x.Trace(ctx, "Streaming data for group: %v", group)
kvs := make(chan *task.KV, 1000)
che := make(chan error)
go writeBatch(ctx, kvs, che)
// We can use count to check the number of posting lists returned in tests.
count := 0
for {
kv, err := stream.Recv()
if err == io.EOF {
break
}
if err != nil {
close(kvs)
return count, err
}
count++
// We check for errors, if there are no errors we send value to channel.
select {
case kvs <- kv:
// OK
case <-ctx.Done():
x.TraceError(ctx, x.Errorf("Context timed out while streaming group: %v", group))
close(kvs)
return count, ctx.Err()
case err := <-che:
x.TraceError(ctx, x.Errorf("Error while doing a batch write for group: %v", group))
close(kvs)
return count, err
}
}
close(kvs)
if err := <-che; err != nil {
x.TraceError(ctx, x.Errorf("Error while doing a batch write for group: %v", group))
return count, err
}
x.Trace(ctx, "Streaming complete for group: %v", group)
return count, nil
}
func deletePrefix(ctx context.Context, client *clientv3.Client, key string) error {
for ctx.Err() == nil {
if _, err := client.Delete(ctx, key, clientv3.WithPrefix()); err == nil {
return nil
}
}
return ctx.Err()
}
func getKey(ctx context.Context, client *clientv3.Client, key string) (*clientv3.GetResponse, error) {
for ctx.Err() == nil {
if gr, err := client.Get(ctx, key); err == nil {
return gr, nil
}
}
return nil, ctx.Err()
}
// writeResult blocks until it can write the result r to the channel c or until
// the context times out.
func writeResult(ctx context.Context, c chan result, r result) error {
select {
case <-ctx.Done():
return ctx.Err()
case c <- r:
return nil
}
}
func waitOnErrChan(ctx context.Context, errs chan error) error {
select {
case err := <-errs:
return err
case <-ctx.Done():
return ctx.Err()
}
}
func (r *Resolver) lookupIP(ctx context.Context, name string) ([]IPAddr, error) {
// TODO(bradfitz,brainman): use ctx more. See TODO below.
type ret struct {
addrs []IPAddr
err error
}
ch := make(chan ret, 1)
go func() {
acquireThread()
defer releaseThread()
hints := syscall.AddrinfoW{
Family: syscall.AF_UNSPEC,
Socktype: syscall.SOCK_STREAM,
Protocol: syscall.IPPROTO_IP,
}
var result *syscall.AddrinfoW
e := syscall.GetAddrInfoW(syscall.StringToUTF16Ptr(name), nil, &hints, &result)
if e != nil {
ch <- ret{err: &DNSError{Err: winError("getaddrinfow", e).Error(), Name: name}}
}
defer syscall.FreeAddrInfoW(result)
addrs := make([]IPAddr, 0, 5)
for ; result != nil; result = result.Next {
addr := unsafe.Pointer(result.Addr)
switch result.Family {
case syscall.AF_INET:
a := (*syscall.RawSockaddrInet4)(addr).Addr
addrs = append(addrs, IPAddr{IP: IPv4(a[0], a[1], a[2], a[3])})
case syscall.AF_INET6:
a := (*syscall.RawSockaddrInet6)(addr).Addr
zone := zoneToString(int((*syscall.RawSockaddrInet6)(addr).Scope_id))
addrs = append(addrs, IPAddr{IP: IP{a[0], a[1], a[2], a[3], a[4], a[5], a[6], a[7], a[8], a[9], a[10], a[11], a[12], a[13], a[14], a[15]}, Zone: zone})
default:
ch <- ret{err: &DNSError{Err: syscall.EWINDOWS.Error(), Name: name}}
}
}
ch <- ret{addrs: addrs}
}()
select {
case r := <-ch:
return r.addrs, r.err
case <-ctx.Done():
// TODO(bradfitz,brainman): cancel the ongoing
// GetAddrInfoW? It would require conditionally using
// GetAddrInfoEx with lpOverlapped, which requires
// Windows 8 or newer. I guess we'll need oldLookupIP,
// newLookupIP, and newerLookUP.
//
// For now we just let it finish and write to the
// buffered channel.
return nil, &DNSError{
Name: name,
Err: ctx.Err().Error(),
IsTimeout: ctx.Err() == context.DeadlineExceeded,
}
}
}
func (s storageWrapper) Clear(ctx context.Context, lookup *Lookup) (deleted int, err error) {
if s.Storer == nil {
return 0, ErrNoStorage
}
if ctx.Err() != nil {
return 0, ctx.Err()
}
return s.Storer.Clear(ctx, lookup)
}
func (s storageWrapper) Delete(ctx context.Context, item *Item) (err error) {
if s.Storer == nil {
return ErrNoStorage
}
if ctx.Err() != nil {
return ctx.Err()
}
return s.Storer.Delete(ctx, item)
}
func (s storageWrapper) Update(ctx context.Context, item *Item, original *Item) (err error) {
if s.Storer == nil {
return ErrNoStorage
}
if ctx.Err() != nil {
return ctx.Err()
}
return s.Storer.Update(ctx, item, original)
}
func (s storageWrapper) Insert(ctx context.Context, items []*Item) (err error) {
if s.Storer == nil {
return ErrNoStorage
}
if ctx.Err() != nil {
return ctx.Err()
}
return s.Storer.Insert(ctx, items)
}
// WaitForTimeoutRaw waits after the context deadline then returns the context
// error. yarpc should interpret this as an handler timeout, which in turns
// should be forwarded to the yarpc client as a remote handler timeout.
func WaitForTimeoutRaw(ctx context.Context, reqMeta yarpc.ReqMeta, body []byte) ([]byte, yarpc.ResMeta, error) {
if _, ok := ctx.Deadline(); !ok {
return nil, nil, fmt.Errorf("no deadline set in context")
}
select {
case <-ctx.Done():
return nil, nil, ctx.Err()
}
}
func HandleRequest(ctx context.Context, req *Request) (*Response, error) {
context := NewQueryContext(req.Queries, req.TimeRange)
batches, err := getBatches(req)
if err != nil {
return nil, err
}
currentlyExecuting := 0
for _, batch := range batches {
if len(batch.Depends) == 0 {
currentlyExecuting += 1
batch.Started = true
go batch.process(ctx, context)
}
}
response := &Response{}
for currentlyExecuting != 0 {
select {
case batchResult := <-context.ResultsChan:
currentlyExecuting -= 1
response.BatchTimings = append(response.BatchTimings, batchResult.Timings)
if batchResult.Error != nil {
return nil, batchResult.Error
}
for refId, result := range batchResult.QueryResults {
context.Results[refId] = result
}
for _, batch := range batches {
// not interested in started batches
if batch.Started {
continue
}
if batch.allDependenciesAreIn(context) {
currentlyExecuting += 1
batch.Started = true
go batch.process(ctx, context)
}
}
case <-ctx.Done():
return nil, ctx.Err()
}
}
response.Results = context.Results
return response, nil
}
// Fsync flushes the content in the file to disk, but does not
// update the dag tree internally
func (fi *FileNode) Fsync(ctx context.Context, req *fuse.FsyncRequest) error {
errs := make(chan error, 1)
go func() {
errs <- fi.fi.Sync()
}()
select {
case err := <-errs:
return err
case <-ctx.Done():
return ctx.Err()
}
}
// CallOneway makes a oneway request
func (o *Outbound) CallOneway(ctx context.Context, treq *transport.Request) (transport.Ack, error) {
if !o.started.Load() {
// panic because there's no recovery from this
panic(errOutboundNotStarted)
}
peer, err := o.getPeerForRequest(ctx, treq)
if err != nil {
return nil, err
}
endRequest := peer.StartRequest()
defer endRequest()
req, err := o.createRequest(peer, treq)
if err != nil {
return nil, err
}
start := time.Now()
var ttl time.Duration
req.Header = applicationHeaders.ToHTTPHeaders(treq.Headers, nil)
ctx, req, span := o.withOpentracingSpan(ctx, req, treq, start)
defer span.Finish()
req = o.withCoreHeaders(req, treq, ttl)
client, err := o.getHTTPClient(peer)
if err != nil {
return nil, err
}
_, err = client.Do(req.WithContext(ctx))
if err != nil {
// Workaround borrowed from ctxhttp until
// https://github.com/golang/go/issues/17711 is resolved.
select {
case <-ctx.Done():
err = ctx.Err()
default:
}
}
sent := time.Now()
if err != nil {
span.SetTag("error", true)
span.LogEvent(err.Error())
return nil, err
}
return ack{time: sent}, nil
}
func (s *stresser) run(ctx context.Context) {
defer s.wg.Done()
for {
if err := s.rateLimiter.Wait(ctx); err == context.Canceled || ctx.Err() == context.Canceled {
return
}
s.mu.Lock()
s.success++
s.mu.Unlock()
}
}
func slowProcess(ctx context.Context) error {
for i := 0; i < 10; i++ {
log.Println("doing something...", i)
select {
case <-time.After(1 * time.Second):
case <-ctx.Done():
log.Println("slowProcess done.", i)
return ctx.Err()
}
}
log.Println("something is done")
return nil
}
func backchannel(ctx context.Context, conn net.Conn) error {
defer trace.End(trace.Begin("establish tether backchannel"))
// HACK: currently RawConn dosn't implement timeout so throttle the spinning
// it does implement the Timeout methods so the intermediary code can be written
// to support it, but they are stub implementation in rawconn impl.
// This needs to tick *faster* than the ticker in connection.go on the
// portlayer side. The PL sends the first syn and if this isn't waiting,
// alignment will take a few rounds (or it may never happen).
ticker := time.NewTicker(10 * time.Millisecond)
defer ticker.Stop()
// We run this in a separate goroutine because HandshakeServer
// calls a Read on rawconn which is a blocking call which causes
// the caller to block as well so this is the only way to cancel.
// Calling Close() will unblock us and on the next tick we will
// return ctx.Err()
go func() {
select {
case <-ctx.Done():
conn.Close()
}
}()
for {
select {
case <-ticker.C:
if ctx.Err() != nil {
return ctx.Err()
}
deadline, ok := ctx.Deadline()
if ok {
conn.SetReadDeadline(deadline)
}
err := serial.HandshakeServer(conn)
if err == nil {
conn.SetReadDeadline(time.Time{})
return nil
}
switch et := err.(type) {
case *serial.HandshakeError:
log.Debugf("HandshakeServer: %v", et)
default:
log.Errorf("HandshakeServer: %v", err)
}
}
}
}