2020-09-09 19:19:03 +02:00
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// Copyright The OpenTelemetry Authors
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package otlp
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import (
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"context"
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"errors"
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Some cleanups in otlp exporter (#1350)
* Drop WorkerCount option
This is not a good option - the user isn't likely to know how many
worker goroutines is optimal. This should be something that an
exporter should figure out itself. The second problem with the option
is that it is specific to the metric transformation from SDK export
format into protobuf. When the exporter starts supporting other
protocols (HTTP/JSON for example), this option may be of no use. So
the option should rather belong to the protocol, not to the
exporter. Currently both mean the same, but later they will be
separated, and this option breaks the separation.
* Make stop channel a typical signalling channel
Signalling channels are idiomatically defined as chan struct{}, so
let's make it so, to avoid confusion about the meaning of the bool
type.
* Close a race when grpc connection is closed multiple times
If several goroutines call Shutdown at the same time, then the
following scenario is possible:
goroutine A locks a mutex, reads a started member, unlocks the mutex
and gets preempted
goroutine B locks a mutex, reads a started member, unlocks the mutex
and gets preempted
goroutine A does not return early in the "if !started" conditional and
continues to close the connection and execute the rest of the function
(where it finally sets the started member to false), gets preempted
goroutine B also does not return early, because it got a copy of
started before goroutine A set it to false, so it tries to close the
connection again.
* Update changelog
2020-11-20 04:03:25 +02:00
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"sync"
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2020-09-09 19:19:03 +02:00
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"testing"
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"time"
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)
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func TestExporterShutdownHonorsTimeout(t *testing.T) {
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ctx, cancel := context.WithTimeout(context.Background(), 1*time.Minute)
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Another batch of cleanups in otlp exporter (#1357)
* Move connection logic into grpcConnection object
If we will need to maintain more than one connection in future, this
splitting off will come in handy.
Co-authored-by: Stefan Prisca <stefan.prisca@gmail.com>
* Make another channel a signal channel
There is another channel that serves as a one-time signal, where
channel's data type does not matter.
* Reorder and document connection members
This is to make clear that the lock is guarding only the connection
since it can be changed by multiple goroutines, and other members are
either atomic or read-only.
* Move stop signal into connection
The stop channel was rather useless on the exporter side - the primary
reason for existence of this channel is to stop a background
reconnecting goroutine. Since the goroutine lives entirely within
grpcConnection object, move the stop channel here. Also expose a
function to unify the stop channel with the context cancellation, so
exporter can use it without knowing anything about stop channels.
Also make export functions a bit more consistent.
* Do not run reconnection routine when being stopped too
It's possible that both disconnected channel and stop channel will be
triggered around the same time, so the goroutine is as likely to start
reconnecting as to return from the goroutine. Make sure we return if
the stop channel is closed.
* Nil clients on connection error
Set clients to nil on connection error, so we don't try to send the
data over a bad connection, but return a "no client" error
immediately.
* Do not call new connection handler within critical section
It's rather risky to call a callback coming from outside within a
critical section. Move it out.
* Add context parameter to connection routines
Connecting to the collector may also take its time, so it can be
useful in some cases to pass a context with a deadline. Currently we
just pass a background context, so this commit does not really change
any behavior. The follow-up commits will make a use of it, though.
* Add context parameter to NewExporter and Start
It makes it possible to limit the time spent on connecting to the
collector.
* Stop connecting on shutdown
Dialling to grpc service ignored the closing of the stop channel, but
this can be easily changed.
* Close connection after background is shut down
That way we can make sure that there won't be a window between closing
a connection and waiting for the background goroutine to return, where
the new connection could be established.
* Remove unnecessary nil check
This member is never nil, unless the Exporter is created like
&Exporter{}, which is not a thing we support anyway.
* Update changelog
Co-authored-by: Stefan Prisca <stefan.prisca@gmail.com>
2020-11-24 21:50:05 +02:00
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defer cancel()
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e := NewUnstartedExporter()
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orig := e.cc.closeBackgroundConnectionDoneCh
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e.cc.closeBackgroundConnectionDoneCh = func(ch chan struct{}) {
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2020-09-09 19:19:03 +02:00
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go func() {
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<-ctx.Done()
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Another batch of cleanups in otlp exporter (#1357)
* Move connection logic into grpcConnection object
If we will need to maintain more than one connection in future, this
splitting off will come in handy.
Co-authored-by: Stefan Prisca <stefan.prisca@gmail.com>
* Make another channel a signal channel
There is another channel that serves as a one-time signal, where
channel's data type does not matter.
* Reorder and document connection members
This is to make clear that the lock is guarding only the connection
since it can be changed by multiple goroutines, and other members are
either atomic or read-only.
* Move stop signal into connection
The stop channel was rather useless on the exporter side - the primary
reason for existence of this channel is to stop a background
reconnecting goroutine. Since the goroutine lives entirely within
grpcConnection object, move the stop channel here. Also expose a
function to unify the stop channel with the context cancellation, so
exporter can use it without knowing anything about stop channels.
Also make export functions a bit more consistent.
* Do not run reconnection routine when being stopped too
It's possible that both disconnected channel and stop channel will be
triggered around the same time, so the goroutine is as likely to start
reconnecting as to return from the goroutine. Make sure we return if
the stop channel is closed.
* Nil clients on connection error
Set clients to nil on connection error, so we don't try to send the
data over a bad connection, but return a "no client" error
immediately.
* Do not call new connection handler within critical section
It's rather risky to call a callback coming from outside within a
critical section. Move it out.
* Add context parameter to connection routines
Connecting to the collector may also take its time, so it can be
useful in some cases to pass a context with a deadline. Currently we
just pass a background context, so this commit does not really change
any behavior. The follow-up commits will make a use of it, though.
* Add context parameter to NewExporter and Start
It makes it possible to limit the time spent on connecting to the
collector.
* Stop connecting on shutdown
Dialling to grpc service ignored the closing of the stop channel, but
this can be easily changed.
* Close connection after background is shut down
That way we can make sure that there won't be a window between closing
a connection and waiting for the background goroutine to return, where
the new connection could be established.
* Remove unnecessary nil check
This member is never nil, unless the Exporter is created like
&Exporter{}, which is not a thing we support anyway.
* Update changelog
Co-authored-by: Stefan Prisca <stefan.prisca@gmail.com>
2020-11-24 21:50:05 +02:00
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orig(ch)
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2020-09-09 19:19:03 +02:00
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}()
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}
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Another batch of cleanups in otlp exporter (#1357)
* Move connection logic into grpcConnection object
If we will need to maintain more than one connection in future, this
splitting off will come in handy.
Co-authored-by: Stefan Prisca <stefan.prisca@gmail.com>
* Make another channel a signal channel
There is another channel that serves as a one-time signal, where
channel's data type does not matter.
* Reorder and document connection members
This is to make clear that the lock is guarding only the connection
since it can be changed by multiple goroutines, and other members are
either atomic or read-only.
* Move stop signal into connection
The stop channel was rather useless on the exporter side - the primary
reason for existence of this channel is to stop a background
reconnecting goroutine. Since the goroutine lives entirely within
grpcConnection object, move the stop channel here. Also expose a
function to unify the stop channel with the context cancellation, so
exporter can use it without knowing anything about stop channels.
Also make export functions a bit more consistent.
* Do not run reconnection routine when being stopped too
It's possible that both disconnected channel and stop channel will be
triggered around the same time, so the goroutine is as likely to start
reconnecting as to return from the goroutine. Make sure we return if
the stop channel is closed.
* Nil clients on connection error
Set clients to nil on connection error, so we don't try to send the
data over a bad connection, but return a "no client" error
immediately.
* Do not call new connection handler within critical section
It's rather risky to call a callback coming from outside within a
critical section. Move it out.
* Add context parameter to connection routines
Connecting to the collector may also take its time, so it can be
useful in some cases to pass a context with a deadline. Currently we
just pass a background context, so this commit does not really change
any behavior. The follow-up commits will make a use of it, though.
* Add context parameter to NewExporter and Start
It makes it possible to limit the time spent on connecting to the
collector.
* Stop connecting on shutdown
Dialling to grpc service ignored the closing of the stop channel, but
this can be easily changed.
* Close connection after background is shut down
That way we can make sure that there won't be a window between closing
a connection and waiting for the background goroutine to return, where
the new connection could be established.
* Remove unnecessary nil check
This member is never nil, unless the Exporter is created like
&Exporter{}, which is not a thing we support anyway.
* Update changelog
Co-authored-by: Stefan Prisca <stefan.prisca@gmail.com>
2020-11-24 21:50:05 +02:00
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if err := e.Start(ctx); err != nil {
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2020-09-09 19:19:03 +02:00
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t.Fatalf("failed to start exporter: %v", err)
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}
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innerCtx, innerCancel := context.WithTimeout(ctx, time.Microsecond)
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if err := e.Shutdown(innerCtx); err == nil {
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t.Error("expected context DeadlineExceeded error, got nil")
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} else if !errors.Is(err, context.DeadlineExceeded) {
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t.Errorf("expected context DeadlineExceeded error, got %v", err)
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}
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innerCancel()
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}
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func TestExporterShutdownHonorsCancel(t *testing.T) {
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ctx, cancel := context.WithTimeout(context.Background(), 1*time.Minute)
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Another batch of cleanups in otlp exporter (#1357)
* Move connection logic into grpcConnection object
If we will need to maintain more than one connection in future, this
splitting off will come in handy.
Co-authored-by: Stefan Prisca <stefan.prisca@gmail.com>
* Make another channel a signal channel
There is another channel that serves as a one-time signal, where
channel's data type does not matter.
* Reorder and document connection members
This is to make clear that the lock is guarding only the connection
since it can be changed by multiple goroutines, and other members are
either atomic or read-only.
* Move stop signal into connection
The stop channel was rather useless on the exporter side - the primary
reason for existence of this channel is to stop a background
reconnecting goroutine. Since the goroutine lives entirely within
grpcConnection object, move the stop channel here. Also expose a
function to unify the stop channel with the context cancellation, so
exporter can use it without knowing anything about stop channels.
Also make export functions a bit more consistent.
* Do not run reconnection routine when being stopped too
It's possible that both disconnected channel and stop channel will be
triggered around the same time, so the goroutine is as likely to start
reconnecting as to return from the goroutine. Make sure we return if
the stop channel is closed.
* Nil clients on connection error
Set clients to nil on connection error, so we don't try to send the
data over a bad connection, but return a "no client" error
immediately.
* Do not call new connection handler within critical section
It's rather risky to call a callback coming from outside within a
critical section. Move it out.
* Add context parameter to connection routines
Connecting to the collector may also take its time, so it can be
useful in some cases to pass a context with a deadline. Currently we
just pass a background context, so this commit does not really change
any behavior. The follow-up commits will make a use of it, though.
* Add context parameter to NewExporter and Start
It makes it possible to limit the time spent on connecting to the
collector.
* Stop connecting on shutdown
Dialling to grpc service ignored the closing of the stop channel, but
this can be easily changed.
* Close connection after background is shut down
That way we can make sure that there won't be a window between closing
a connection and waiting for the background goroutine to return, where
the new connection could be established.
* Remove unnecessary nil check
This member is never nil, unless the Exporter is created like
&Exporter{}, which is not a thing we support anyway.
* Update changelog
Co-authored-by: Stefan Prisca <stefan.prisca@gmail.com>
2020-11-24 21:50:05 +02:00
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defer cancel()
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e := NewUnstartedExporter()
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orig := e.cc.closeBackgroundConnectionDoneCh
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e.cc.closeBackgroundConnectionDoneCh = func(ch chan struct{}) {
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2020-09-09 19:19:03 +02:00
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go func() {
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<-ctx.Done()
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Another batch of cleanups in otlp exporter (#1357)
* Move connection logic into grpcConnection object
If we will need to maintain more than one connection in future, this
splitting off will come in handy.
Co-authored-by: Stefan Prisca <stefan.prisca@gmail.com>
* Make another channel a signal channel
There is another channel that serves as a one-time signal, where
channel's data type does not matter.
* Reorder and document connection members
This is to make clear that the lock is guarding only the connection
since it can be changed by multiple goroutines, and other members are
either atomic or read-only.
* Move stop signal into connection
The stop channel was rather useless on the exporter side - the primary
reason for existence of this channel is to stop a background
reconnecting goroutine. Since the goroutine lives entirely within
grpcConnection object, move the stop channel here. Also expose a
function to unify the stop channel with the context cancellation, so
exporter can use it without knowing anything about stop channels.
Also make export functions a bit more consistent.
* Do not run reconnection routine when being stopped too
It's possible that both disconnected channel and stop channel will be
triggered around the same time, so the goroutine is as likely to start
reconnecting as to return from the goroutine. Make sure we return if
the stop channel is closed.
* Nil clients on connection error
Set clients to nil on connection error, so we don't try to send the
data over a bad connection, but return a "no client" error
immediately.
* Do not call new connection handler within critical section
It's rather risky to call a callback coming from outside within a
critical section. Move it out.
* Add context parameter to connection routines
Connecting to the collector may also take its time, so it can be
useful in some cases to pass a context with a deadline. Currently we
just pass a background context, so this commit does not really change
any behavior. The follow-up commits will make a use of it, though.
* Add context parameter to NewExporter and Start
It makes it possible to limit the time spent on connecting to the
collector.
* Stop connecting on shutdown
Dialling to grpc service ignored the closing of the stop channel, but
this can be easily changed.
* Close connection after background is shut down
That way we can make sure that there won't be a window between closing
a connection and waiting for the background goroutine to return, where
the new connection could be established.
* Remove unnecessary nil check
This member is never nil, unless the Exporter is created like
&Exporter{}, which is not a thing we support anyway.
* Update changelog
Co-authored-by: Stefan Prisca <stefan.prisca@gmail.com>
2020-11-24 21:50:05 +02:00
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orig(ch)
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2020-09-09 19:19:03 +02:00
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}()
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}
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Another batch of cleanups in otlp exporter (#1357)
* Move connection logic into grpcConnection object
If we will need to maintain more than one connection in future, this
splitting off will come in handy.
Co-authored-by: Stefan Prisca <stefan.prisca@gmail.com>
* Make another channel a signal channel
There is another channel that serves as a one-time signal, where
channel's data type does not matter.
* Reorder and document connection members
This is to make clear that the lock is guarding only the connection
since it can be changed by multiple goroutines, and other members are
either atomic or read-only.
* Move stop signal into connection
The stop channel was rather useless on the exporter side - the primary
reason for existence of this channel is to stop a background
reconnecting goroutine. Since the goroutine lives entirely within
grpcConnection object, move the stop channel here. Also expose a
function to unify the stop channel with the context cancellation, so
exporter can use it without knowing anything about stop channels.
Also make export functions a bit more consistent.
* Do not run reconnection routine when being stopped too
It's possible that both disconnected channel and stop channel will be
triggered around the same time, so the goroutine is as likely to start
reconnecting as to return from the goroutine. Make sure we return if
the stop channel is closed.
* Nil clients on connection error
Set clients to nil on connection error, so we don't try to send the
data over a bad connection, but return a "no client" error
immediately.
* Do not call new connection handler within critical section
It's rather risky to call a callback coming from outside within a
critical section. Move it out.
* Add context parameter to connection routines
Connecting to the collector may also take its time, so it can be
useful in some cases to pass a context with a deadline. Currently we
just pass a background context, so this commit does not really change
any behavior. The follow-up commits will make a use of it, though.
* Add context parameter to NewExporter and Start
It makes it possible to limit the time spent on connecting to the
collector.
* Stop connecting on shutdown
Dialling to grpc service ignored the closing of the stop channel, but
this can be easily changed.
* Close connection after background is shut down
That way we can make sure that there won't be a window between closing
a connection and waiting for the background goroutine to return, where
the new connection could be established.
* Remove unnecessary nil check
This member is never nil, unless the Exporter is created like
&Exporter{}, which is not a thing we support anyway.
* Update changelog
Co-authored-by: Stefan Prisca <stefan.prisca@gmail.com>
2020-11-24 21:50:05 +02:00
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if err := e.Start(ctx); err != nil {
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2020-09-09 19:19:03 +02:00
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t.Fatalf("failed to start exporter: %v", err)
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}
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var innerCancel context.CancelFunc
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ctx, innerCancel = context.WithCancel(ctx)
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innerCancel()
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if err := e.Shutdown(ctx); err == nil {
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t.Error("expected context canceled error, got nil")
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} else if !errors.Is(err, context.Canceled) {
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t.Errorf("expected context canceled error, got %v", err)
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}
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}
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func TestExporterShutdownNoError(t *testing.T) {
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ctx, cancel := context.WithTimeout(context.Background(), 1*time.Minute)
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defer cancel()
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e := NewUnstartedExporter()
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Another batch of cleanups in otlp exporter (#1357)
* Move connection logic into grpcConnection object
If we will need to maintain more than one connection in future, this
splitting off will come in handy.
Co-authored-by: Stefan Prisca <stefan.prisca@gmail.com>
* Make another channel a signal channel
There is another channel that serves as a one-time signal, where
channel's data type does not matter.
* Reorder and document connection members
This is to make clear that the lock is guarding only the connection
since it can be changed by multiple goroutines, and other members are
either atomic or read-only.
* Move stop signal into connection
The stop channel was rather useless on the exporter side - the primary
reason for existence of this channel is to stop a background
reconnecting goroutine. Since the goroutine lives entirely within
grpcConnection object, move the stop channel here. Also expose a
function to unify the stop channel with the context cancellation, so
exporter can use it without knowing anything about stop channels.
Also make export functions a bit more consistent.
* Do not run reconnection routine when being stopped too
It's possible that both disconnected channel and stop channel will be
triggered around the same time, so the goroutine is as likely to start
reconnecting as to return from the goroutine. Make sure we return if
the stop channel is closed.
* Nil clients on connection error
Set clients to nil on connection error, so we don't try to send the
data over a bad connection, but return a "no client" error
immediately.
* Do not call new connection handler within critical section
It's rather risky to call a callback coming from outside within a
critical section. Move it out.
* Add context parameter to connection routines
Connecting to the collector may also take its time, so it can be
useful in some cases to pass a context with a deadline. Currently we
just pass a background context, so this commit does not really change
any behavior. The follow-up commits will make a use of it, though.
* Add context parameter to NewExporter and Start
It makes it possible to limit the time spent on connecting to the
collector.
* Stop connecting on shutdown
Dialling to grpc service ignored the closing of the stop channel, but
this can be easily changed.
* Close connection after background is shut down
That way we can make sure that there won't be a window between closing
a connection and waiting for the background goroutine to return, where
the new connection could be established.
* Remove unnecessary nil check
This member is never nil, unless the Exporter is created like
&Exporter{}, which is not a thing we support anyway.
* Update changelog
Co-authored-by: Stefan Prisca <stefan.prisca@gmail.com>
2020-11-24 21:50:05 +02:00
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if err := e.Start(ctx); err != nil {
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2020-09-09 19:19:03 +02:00
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t.Fatalf("failed to start exporter: %v", err)
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}
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if err := e.Shutdown(ctx); err != nil {
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t.Errorf("shutdown errored: expected nil, got %v", err)
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}
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}
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Some cleanups in otlp exporter (#1350)
* Drop WorkerCount option
This is not a good option - the user isn't likely to know how many
worker goroutines is optimal. This should be something that an
exporter should figure out itself. The second problem with the option
is that it is specific to the metric transformation from SDK export
format into protobuf. When the exporter starts supporting other
protocols (HTTP/JSON for example), this option may be of no use. So
the option should rather belong to the protocol, not to the
exporter. Currently both mean the same, but later they will be
separated, and this option breaks the separation.
* Make stop channel a typical signalling channel
Signalling channels are idiomatically defined as chan struct{}, so
let's make it so, to avoid confusion about the meaning of the bool
type.
* Close a race when grpc connection is closed multiple times
If several goroutines call Shutdown at the same time, then the
following scenario is possible:
goroutine A locks a mutex, reads a started member, unlocks the mutex
and gets preempted
goroutine B locks a mutex, reads a started member, unlocks the mutex
and gets preempted
goroutine A does not return early in the "if !started" conditional and
continues to close the connection and execute the rest of the function
(where it finally sets the started member to false), gets preempted
goroutine B also does not return early, because it got a copy of
started before goroutine A set it to false, so it tries to close the
connection again.
* Update changelog
2020-11-20 04:03:25 +02:00
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func TestExporterShutdownManyTimes(t *testing.T) {
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ctx := context.Background()
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Another batch of cleanups in otlp exporter (#1357)
* Move connection logic into grpcConnection object
If we will need to maintain more than one connection in future, this
splitting off will come in handy.
Co-authored-by: Stefan Prisca <stefan.prisca@gmail.com>
* Make another channel a signal channel
There is another channel that serves as a one-time signal, where
channel's data type does not matter.
* Reorder and document connection members
This is to make clear that the lock is guarding only the connection
since it can be changed by multiple goroutines, and other members are
either atomic or read-only.
* Move stop signal into connection
The stop channel was rather useless on the exporter side - the primary
reason for existence of this channel is to stop a background
reconnecting goroutine. Since the goroutine lives entirely within
grpcConnection object, move the stop channel here. Also expose a
function to unify the stop channel with the context cancellation, so
exporter can use it without knowing anything about stop channels.
Also make export functions a bit more consistent.
* Do not run reconnection routine when being stopped too
It's possible that both disconnected channel and stop channel will be
triggered around the same time, so the goroutine is as likely to start
reconnecting as to return from the goroutine. Make sure we return if
the stop channel is closed.
* Nil clients on connection error
Set clients to nil on connection error, so we don't try to send the
data over a bad connection, but return a "no client" error
immediately.
* Do not call new connection handler within critical section
It's rather risky to call a callback coming from outside within a
critical section. Move it out.
* Add context parameter to connection routines
Connecting to the collector may also take its time, so it can be
useful in some cases to pass a context with a deadline. Currently we
just pass a background context, so this commit does not really change
any behavior. The follow-up commits will make a use of it, though.
* Add context parameter to NewExporter and Start
It makes it possible to limit the time spent on connecting to the
collector.
* Stop connecting on shutdown
Dialling to grpc service ignored the closing of the stop channel, but
this can be easily changed.
* Close connection after background is shut down
That way we can make sure that there won't be a window between closing
a connection and waiting for the background goroutine to return, where
the new connection could be established.
* Remove unnecessary nil check
This member is never nil, unless the Exporter is created like
&Exporter{}, which is not a thing we support anyway.
* Update changelog
Co-authored-by: Stefan Prisca <stefan.prisca@gmail.com>
2020-11-24 21:50:05 +02:00
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e, err := NewExporter(ctx)
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Some cleanups in otlp exporter (#1350)
* Drop WorkerCount option
This is not a good option - the user isn't likely to know how many
worker goroutines is optimal. This should be something that an
exporter should figure out itself. The second problem with the option
is that it is specific to the metric transformation from SDK export
format into protobuf. When the exporter starts supporting other
protocols (HTTP/JSON for example), this option may be of no use. So
the option should rather belong to the protocol, not to the
exporter. Currently both mean the same, but later they will be
separated, and this option breaks the separation.
* Make stop channel a typical signalling channel
Signalling channels are idiomatically defined as chan struct{}, so
let's make it so, to avoid confusion about the meaning of the bool
type.
* Close a race when grpc connection is closed multiple times
If several goroutines call Shutdown at the same time, then the
following scenario is possible:
goroutine A locks a mutex, reads a started member, unlocks the mutex
and gets preempted
goroutine B locks a mutex, reads a started member, unlocks the mutex
and gets preempted
goroutine A does not return early in the "if !started" conditional and
continues to close the connection and execute the rest of the function
(where it finally sets the started member to false), gets preempted
goroutine B also does not return early, because it got a copy of
started before goroutine A set it to false, so it tries to close the
connection again.
* Update changelog
2020-11-20 04:03:25 +02:00
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if err != nil {
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t.Fatalf("failed to start an exporter: %v", err)
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}
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ch := make(chan struct{})
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wg := sync.WaitGroup{}
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const num int = 20
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wg.Add(num)
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errs := make([]error, num)
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for i := 0; i < num; i++ {
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go func(idx int) {
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defer wg.Done()
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<-ch
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errs[idx] = e.Shutdown(ctx)
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}(i)
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}
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close(ch)
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wg.Wait()
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for _, err := range errs {
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if err != nil {
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t.Fatalf("failed to shutdown exporter: %v", err)
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}
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}
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}
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