CNF-23380: Migrate away from deprecated ioutil

[sebrandon1]

ioutil has been deprecated since Go 1.16: https://go.dev/doc/go1.16#ioutil

Tracking issue: redhat-best-practices-for-k8s/telco-bot#52

Summary by CodeRabbit

• Chores
  • Updated internal code to use current Go standard library functions, replacing deprecated APIs with their modern equivalents.

[coderabbitai]

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Walkthrough

Replaces deprecated io/ioutil function calls with their os package equivalents: ioutil.ReadFile → os.ReadFile in the serving cert starter, and ioutil.TempFile → os.CreateTemp in the test rotate utility. Both io/ioutil imports are removed.

Changes

ioutil deprecation cleanup

Layer / File(s)	Summary
Replace ioutil with os equivalents pkg/controller/servingcert/starter/starter.go, test/util/rotate.go	Removes io/ioutil imports and substitutes os.ReadFile for ioutil.ReadFile in readIntermediateCACert, and os.CreateTemp for ioutil.TempFile in checkClientTrust (cert and key temp files). No behavioral changes.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

🚥 Pre-merge checks | ✅ 13 | ❌ 2

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 66.67% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.
Microshift Test Compatibility	⚠️ Warning	New Ginkgo e2e tests added in test/e2e/network_policy.go use ClusterOperator API (config.openshift.io/v1) without MicroShift protection or apigroup tags.	Add [apigroup:config.openshift.io] tag to test names, or add [Skipped:MicroShift] label, or guard with exutil.IsMicroShiftCluster() check.

✅ Passed checks (13 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes the main objective of the PR: migrating away from the deprecated ioutil package, which is reflected in both files changed.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Stable And Deterministic Test Names	✅ Passed	PR modifies non-Ginkgo code (production file and test utility helpers). No Ginkgo test definitions (It(), Describe(), Context(), When()) exist in modified files, so the stable test names check does...
Test Structure And Quality	✅ Passed	PR modifies only production code (pkg/controller/servingcert/starter/starter.go) and test utility code (test/util/rotate.go), not Ginkgo test files themselves. The custom check is not applicable.
Single Node Openshift (Sno) Test Compatibility	✅ Passed	PR does not add any new Ginkgo e2e tests; it only migrates deprecated ioutil calls to os package equivalents in utility and controller code.
Topology-Aware Scheduling Compatibility	✅ Passed	PR only modernizes deprecated ioutil calls to os equivalents in utility functions; contains no deployment manifests, scheduling constraints, or topology-related code changes.
Ote Binary Stdout Contract	✅ Passed	The PR only replaces deprecated ioutil functions with modern os equivalents (ioutil.ReadFile→os.ReadFile, ioutil.TempFile→os.CreateTemp). No stdout/stderr writes, logging configuration changes, or...
Ipv6 And Disconnected Network Test Compatibility	✅ Passed	PR contains no new Ginkgo e2e tests; it only updates deprecated ioutil calls to standard library equivalents in non-test and utility code.
No-Weak-Crypto	✅ Passed	PR migrates from deprecated ioutil to os package (os.ReadFile, os.CreateTemp). No weak crypto (MD5, SHA1, DES, RC4, 3DES, Blowfish, ECB), custom crypto implementations, or insecure secret compariso...
Container-Privileges	✅ Passed	PR modifies only Go source files for ioutil deprecation migration, not Kubernetes/container manifests. The container-privileges check is not applicable to this PR's scope.
No-Sensitive-Data-In-Logs	✅ Passed	PR only replaces deprecated ioutil functions with os equivalents; no new logging added that exposes passwords, tokens, API keys, PII, session IDs, or sensitive data.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[xingxingxia]

@sebrandon1 @coderabbitai

service-ca-operator/pkg/operator/v4_00_assets/bindata.go

Line 614 in f5a143a

err = ioutil.WriteFile(_filePath(dir, name), data, info.Mode())

has one ioutil.

[coderabbitai]

Tip

For best results, initiate chat on the files or code changes.

🧩 Analysis chain

🏁 Script executed:

#!/bin/bash
# Check the specific file mentioned by the user
echo "=== Examining pkg/operator/v4_00_assets/bindata.go ==="
cat pkg/operator/v4_00_assets/bindata.go | head -20
echo ""
echo "=== Looking for ioutil usage around line 614 ==="
sed -n '610,620p' pkg/operator/v4_00_assets/bindata.go

echo ""
echo "=== Searching for all remaining ioutil usages in the codebase ==="
rg -n 'ioutil\.' --type=go

echo ""
echo "=== Checking if bindata.go is a generated file ==="
head -5 pkg/operator/v4_00_assets/bindata.go

Length of output: 1466

---

@xingxingxia @sebrandon1 Good catch! I've verified that pkg/operator/v4_00_assets/bindata.go line 614 does indeed contain a remaining ioutil.WriteFile usage (and an io/ioutil import on line 15). This is actually the only remaining ioutil usage in the entire codebase.

However, this file is a generated file created by go-bindata, as indicated by the header comment:

// Code generated for package v4_00_assets by go-bindata DO NOT EDIT. (@generated)

To address this ioutil usage, you'll need to:

1. Regenerate the bindata file using the go-bindata tool (or its replacement) with updated code that uses os.WriteFile instead of ioutil.WriteFile
2. Check if you're using an older version of go-bindata that still generates ioutil calls, and update to a newer version if available
3. Alternatively, consider migrating to a more modern alternative like go:embed (introduced in Go 1.16) if feasible for your use case

Would you like me to help investigate the bindata generation process or search for the command/script that generates this file?

[sebrandon1]

Yes, this is bindata so I didn't edit that file.

[xingxingxia]

Maybe it needs regenerated to be updated?

[sebrandon1]

I think that's a good plan. I wonder if that should be a separate PR because regenerating might encompass more changes than just ioutil.

[sebrandon1]

/retest

[openshift-ci-robot]

@sebrandon1: This pull request references CNF-23380 which is a valid jira issue.

Warning: The referenced jira issue has an invalid target version for the target branch this PR targets: expected the story to target the "5.0.0" version, but no target version was set.

Details

In response to this:

ioutil has been deprecated since Go 1.16: https://go.dev/doc/go1.16#ioutil

Tracking issue: redhat-best-practices-for-k8s/telco-bot#52

Summary by CodeRabbit

• Chores
• Upgraded internal code to use current standard library versions.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the openshift-eng/jira-lifecycle-plugin repository.

[openshift-ci]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[openshift-ci]

@sebrandon1: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/e2e-aws-operator	fafa0d2	link	true	/test e2e-aws-operator
ci/prow/e2e-aws	fafa0d2	link	true	/test e2e-aws

Full PR test history. Your PR dashboard.

Details

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