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chromium/external/github.com/grpc/grpc-go/b7b1cce6ed34aefd678d696d5f474890c5e6dd6d
commit
b7b1cce6ed34aefd678d696d5f474890c5e6dd6d
[log]
author
Arjan Singh Bal <46515553+arjan-bal@users.noreply.github.com>
Tue Feb 03 06:22:08 2026
committer
GitHub <noreply@github.com>
Tue Feb 03 06:22:08 2026
tree
c768df93aae613c5afdec6c473b3cef53b150fcf
parent
2abe1f0db17e047778082c460589c81b3472f359 [diff]
examples: Poll for expected server logs in test (#8871)

Fixes: #8046

## Problem

The test is flaky due to a race condition in the driver script.
Currently, the script waits for the client to exit and immediately
validates the server output:
https://github.com/grpc/grpc-go/blob/49e224f832c21df2cd3fe833189c8a50244f0eee/examples/examples_test.sh#L195-L219

In the graceful shutdown example, the expected log is written only after
the shutdown is complete:
https://github.com/grpc/grpc-go/blob/49e224f832c21df2cd3fe833189c8a50244f0eee/examples/features/gracefulstop/server/main.go#L99

If the test driver validates the server output after the client stream
closes but before the server logs the expected message, the test fails.

## Fix

This PR updates the test driver to poll for the expected log in the
server output, instead of checking it only once. Additionally, the
shutdown of the test server is blocked until either the server logs a
failure or a success message.
## Validation

To reproduce the failure, I added a 1s sleep just before the line
`log.Println("Server stopped gracefully.")` in the server code. I
verified that the test no longer fails with this fix, even with the
artificial delay.

RELEASE NOTES: N/A
2 files changed
tree: c768df93aae613c5afdec6c473b3cef53b150fcf
  1. .gemini/
  2. .github/
  3. admin/
  4. attributes/
  5. authz/
  6. backoff/
  7. balancer/
  8. benchmark/
  9. binarylog/
  10. channelz/
  11. cmd/
  12. codes/
  13. connectivity/
  14. credentials/
  15. Documentation/
  16. encoding/
  17. examples/
  18. experimental/
  19. gcp/
  20. grpclog/
  21. health/
  22. internal/
  23. interop/
  24. keepalive/
  25. mem/
  26. metadata/
  27. orca/
  28. peer/
  29. profiling/
  30. reflection/
  31. resolver/
  32. scripts/
  33. security/
  34. serviceconfig/
  35. stats/
  36. status/
  37. tap/
  38. test/
  39. testdata/
  40. xds/
  41. AUTHORS
  42. backoff.go
  43. balancer_wrapper.go
  44. balancer_wrapper_test.go
  45. call.go
  46. clientconn.go
  47. clientconn_authority_test.go
  48. clientconn_parsed_target_test.go
  49. clientconn_test.go
  50. CODE-OF-CONDUCT.md
  51. codec.go
  52. codec_test.go
  53. CONTRIBUTING.md
  54. default_dial_option_server_option_test.go
  55. dial_test.go
  56. dialoptions.go
  57. doc.go
  58. go.mod
  59. go.sum
  60. GOVERNANCE.md
  61. grpc_test.go
  62. interceptor.go
  63. LICENSE
  64. MAINTAINERS.md
  65. Makefile
  66. NOTICE.txt
  67. picker_wrapper.go
  68. picker_wrapper_test.go
  69. preloader.go
  70. producer_ext_test.go
  71. README.md
  72. resolver_balancer_ext_test.go
  73. resolver_test.go
  74. resolver_wrapper.go
  75. rpc_util.go
  76. rpc_util_test.go
  77. SECURITY.md
  78. server.go
  79. server_ext_test.go
  80. server_test.go
  81. service_config.go
  82. service_config_test.go
  83. stream.go
  84. stream_interfaces.go
  85. stream_test.go
  86. trace.go
  87. trace_notrace.go
  88. trace_test.go
  89. trace_withtrace.go
  90. version.go
README.md

gRPC-Go

GoDoc GoReportCard codecov

The Go implementation of gRPC: A high performance, open source, general RPC framework that puts mobile and HTTP/2 first. For more information see the Go gRPC docs, or jump directly into the quick start.

Prerequisites

Installation

Simply add the following import to your code, and then go [build|run|test] will automatically fetch the necessary dependencies:

import "google.golang.org/grpc"

Note: If you are trying to access grpc-go from China, see the FAQ below.

Learn more

FAQ

I/O Timeout Errors

The golang.org domain may be blocked from some countries. go get usually produces an error like the following when this happens:

$ go get -u google.golang.org/grpc
package google.golang.org/grpc: unrecognized import path "google.golang.org/grpc" (https fetch: Get https://google.golang.org/grpc?go-get=1: dial tcp 216.239.37.1:443: i/o timeout)

To build Go code, there are several options:

  • Set up a VPN and access google.golang.org through that.

  • With Go module support: it is possible to use the replace feature of go mod to create aliases for golang.org packages. In your project's directory:

    go mod edit -replace=google.golang.org/grpc=github.com/grpc/grpc-go@latest
go mod tidy
go mod vendor
go build -mod=vendor

    Again, this will need to be done for all transitive dependencies hosted on golang.org as well. For details, refer to golang/go issue #28652.

Compiling error, undefined: grpc.SupportPackageIsVersion

Please update to the latest version of gRPC-Go using go get google.golang.org/grpc.

How to turn on logging

The default logger is controlled by environment variables. Turn everything on like this:

$ export GRPC_GO_LOG_VERBOSITY_LEVEL=99
$ export GRPC_GO_LOG_SEVERITY_LEVEL=info

The RPC failed with error "code = Unavailable desc = transport is closing"

This error means the connection the RPC is using was closed, and there are many possible reasons, including:

  1. mis-configured transport credentials, connection failed on handshaking
  2. bytes disrupted, possibly by a proxy in between
  3. server shutdown
  4. Keepalive parameters caused connection shutdown, for example if you have configured your server to terminate connections regularly to trigger DNS lookups. If this is the case, you may want to increase your MaxConnectionAgeGrace, to allow longer RPC calls to finish.

It can be tricky to debug this because the error happens on the client side but the root cause of the connection being closed is on the server side. Turn on logging on both client and server, and see if there are any transport errors.