Fix data race on injectedHTTPClient in client package

[Copilot]

Flaky CI failures due to a data race on the package-level injectedHTTPClient variable. TestGetHTTPClient and TestHttpClientProvidesOAuth2BearerToken both run with t.Parallel() and concurrently read/write the unprotected global, tripping the -race detector and cascading failures to all concurrent tests in the package.

• Add sync.RWMutex to guard injectedHTTPClient access in GetHTTPClient() (read) and InjectHTTPClient() (write)

var (
	injectedHTTPClient  *http.Client
	injectedHTTPClientM sync.RWMutex
)

func GetHTTPClient(config *Config) *http.Client {
	injectedHTTPClientM.RLock()
	defer injectedHTTPClientM.RUnlock()
	if injectedHTTPClient != nil {
		return injectedHTTPClient
	}
	// ...
}

func InjectHTTPClient(httpClient *http.Client) {
	injectedHTTPClientM.Lock()
	injectedHTTPClient = httpClient
	injectedHTTPClientM.Unlock()
}

Confirmed with go test -race -count=10 — zero races across iterations.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• 1.0.0.1.in-addr.arpa
  • Triggering command: /tmp/go-build3186497109/b001/client.test /tmp/go-build3186497109/b001/client.test -test.paniconexit0 -test.timeout=10m0s -test.count=1 /tmp/go-build3186497109/b349/vet.cfg g_.a /tmp/go-build269go1.25.5 4/pkg/tool/linux_amd64/vet . /icmp mpile 4/pkg/tool/linux-buildtags -I chain@v0.0.1-go1-errorsas mpile 4/pkg/tool/linux_amd64/vet AFX9BbFhU /go/auth/credent-atomic mpile 4/pkg/tool/linux-buildtags (dns block)
• 192.168.152.153
  • Triggering command: REDACTED, pid is -1 (packet block)
• 8.8.8.8.in-addr.arpa
  • Triggering command: /tmp/go-build3186497109/b001/client.test /tmp/go-build3186497109/b001/client.test -test.paniconexit0 -test.timeout=10m0s -test.count=1 /tmp/go-build3186497109/b349/vet.cfg g_.a /tmp/go-build269go1.25.5 4/pkg/tool/linux_amd64/vet . /icmp mpile 4/pkg/tool/linux-buildtags -I chain@v0.0.1-go1-errorsas mpile 4/pkg/tool/linux_amd64/vet AFX9BbFhU /go/auth/credent-atomic mpile 4/pkg/tool/linux-buildtags (dns block)
• data.iana.org
  • Triggering command: /tmp/go-build3186497109/b001/client.test /tmp/go-build3186497109/b001/client.test -test.paniconexit0 -test.timeout=10m0s -test.count=1 /tmp/go-build3186497109/b349/vet.cfg g_.a /tmp/go-build269go1.25.5 4/pkg/tool/linux_amd64/vet . /icmp mpile 4/pkg/tool/linux-buildtags -I chain@v0.0.1-go1-errorsas mpile 4/pkg/tool/linux_amd64/vet AFX9BbFhU /go/auth/credent-atomic mpile 4/pkg/tool/linux-buildtags (dns block)
• en.wikipedia.org
  • Triggering command: /tmp/go-build3186497109/b001/client.test /tmp/go-build3186497109/b001/client.test -test.paniconexit0 -test.timeout=10m0s -test.count=1 /tmp/go-build3186497109/b349/vet.cfg g_.a /tmp/go-build269go1.25.5 4/pkg/tool/linux_amd64/vet . /icmp mpile 4/pkg/tool/linux-buildtags -I chain@v0.0.1-go1-errorsas mpile 4/pkg/tool/linux_amd64/vet AFX9BbFhU /go/auth/credent-atomic mpile 4/pkg/tool/linux-buildtags (dns block)
• example.com
  • Triggering command: /tmp/go-build3186497109/b001/client.test /tmp/go-build3186497109/b001/client.test -test.paniconexit0 -test.timeout=10m0s -test.count=1 /tmp/go-build3186497109/b349/vet.cfg g_.a /tmp/go-build269go1.25.5 4/pkg/tool/linux_amd64/vet . /icmp mpile 4/pkg/tool/linux-buildtags -I chain@v0.0.1-go1-errorsas mpile 4/pkg/tool/linux_amd64/vet AFX9BbFhU /go/auth/credent-atomic mpile 4/pkg/tool/linux-buildtags (dns block)
• example.org
  • Triggering command: /tmp/go-build3186497109/b001/client.test /tmp/go-build3186497109/b001/client.test -test.paniconexit0 -test.timeout=10m0s -test.count=1 /tmp/go-build3186497109/b349/vet.cfg g_.a /tmp/go-build269go1.25.5 4/pkg/tool/linux_amd64/vet . /icmp mpile 4/pkg/tool/linux-buildtags -I chain@v0.0.1-go1-errorsas mpile 4/pkg/tool/linux_amd64/vet AFX9BbFhU /go/auth/credent-atomic mpile 4/pkg/tool/linux-buildtags (dns block)
• expired.badssl.com
  • Triggering command: /tmp/go-build3186497109/b001/client.test /tmp/go-build3186497109/b001/client.test -test.paniconexit0 -test.timeout=10m0s -test.count=1 /tmp/go-build3186497109/b349/vet.cfg g_.a /tmp/go-build269go1.25.5 4/pkg/tool/linux_amd64/vet . /icmp mpile 4/pkg/tool/linux-buildtags -I chain@v0.0.1-go1-errorsas mpile 4/pkg/tool/linux_amd64/vet AFX9BbFhU /go/auth/credent-atomic mpile 4/pkg/tool/linux-buildtags (dns block)
• idontplaytheodds.com
  • Triggering command: /tmp/go-build3186497109/b001/client.test /tmp/go-build3186497109/b001/client.test -test.paniconexit0 -test.timeout=10m0s -test.count=1 /tmp/go-build3186497109/b349/vet.cfg g_.a /tmp/go-build269go1.25.5 4/pkg/tool/linux_amd64/vet . /icmp mpile 4/pkg/tool/linux-buildtags -I chain@v0.0.1-go1-errorsas mpile 4/pkg/tool/linux_amd64/vet AFX9BbFhU /go/auth/credent-atomic mpile 4/pkg/tool/linux-buildtags (dns block)
• smtp.gmail.com
  • Triggering command: /tmp/go-build3186497109/b001/client.test /tmp/go-build3186497109/b001/client.test -test.paniconexit0 -test.timeout=10m0s -test.count=1 /tmp/go-build3186497109/b349/vet.cfg g_.a /tmp/go-build269go1.25.5 4/pkg/tool/linux_amd64/vet . /icmp mpile 4/pkg/tool/linux-buildtags -I chain@v0.0.1-go1-errorsas mpile 4/pkg/tool/linux_amd64/vet AFX9BbFhU /go/auth/credent-atomic mpile 4/pkg/tool/linux-buildtags (dns block)
• test
  • Triggering command: /tmp/go-build3186497109/b001/client.test /tmp/go-build3186497109/b001/client.test -test.paniconexit0 -test.timeout=10m0s -test.count=1 /tmp/go-build3186497109/b349/vet.cfg g_.a /tmp/go-build269go1.25.5 4/pkg/tool/linux_amd64/vet . /icmp mpile 4/pkg/tool/linux-buildtags -I chain@v0.0.1-go1-errorsas mpile 4/pkg/tool/linux_amd64/vet AFX9BbFhU /go/auth/credent-atomic mpile 4/pkg/tool/linux-buildtags (dns block)
• tty.sdf.org
  • Triggering command: /tmp/go-build3186497109/b001/client.test /tmp/go-build3186497109/b001/client.test -test.paniconexit0 -test.timeout=10m0s -test.count=1 /tmp/go-build3186497109/b349/vet.cfg g_.a /tmp/go-build269go1.25.5 4/pkg/tool/linux_amd64/vet . /icmp mpile 4/pkg/tool/linux-buildtags -I chain@v0.0.1-go1-errorsas mpile 4/pkg/tool/linux_amd64/vet AFX9BbFhU /go/auth/credent-atomic mpile 4/pkg/tool/linux-buildtags (dns block)
• whois.nic.io
  • Triggering command: /tmp/go-build3186497109/b001/client.test /tmp/go-build3186497109/b001/client.test -test.paniconexit0 -test.timeout=10m0s -test.count=1 /tmp/go-build3186497109/b349/vet.cfg g_.a /tmp/go-build269go1.25.5 4/pkg/tool/linux_amd64/vet . /icmp mpile 4/pkg/tool/linux-buildtags -I chain@v0.0.1-go1-errorsas mpile 4/pkg/tool/linux_amd64/vet AFX9BbFhU /go/auth/credent-atomic mpile 4/pkg/tool/linux-buildtags (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

Reference: https://github.com/TwiN/gatus/commit/12be9facdafa392693264c59e384ba101285c71a/checks?check_suite_id=63018577703

investigate the flaky test

[OrionOth]

@TwiN I'd like to object strongly to merging this pull request for a variety of reasons. Furthermore, I'd like to request a reversion of commits 64116ce, f925cb4 and 7208880.
It's not too late to stay on the bright path. Please don't plagiarize and ruin this software you've worked so hard on for almost 7 years now!

[TwiN]

@OrionOth I understand your stance, alas, I don't personally think there's much that can be done to prevent the usage of LLMs from becoming the norm.

I would rather create instructions (that's what some of the commits you pointed out are for) for agents to both direct them and request agents identify themselves (model/version) properly via PRs so that I can treat the PRs as such (more carefully).

At this point, I'd be willing to bet most new PRs are generated using AI agents already.

[OrionOth]

@TwiN There seems to be some consensus that Ghostty's AI policy is one of the best an open source project can get. I don't personally agree, but as far as limiting actual slop I think it would do a fairly good job.