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

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

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Walkthrough

Replace deprecated ioutil calls with their modern os equivalents across reading and temp-file creation sites; remove now-unused ioutil imports. No functional or error-handling behavior changes.

Changes

Cohort / File(s)	Summary
CA bundle and serving cert readers pkg/controller/cabundleinjector/starter.go, pkg/controller/servingcert/starter/starter.go	Replace ioutil.ReadFile with os.ReadFile; adjust imports (remove ioutil, reorder as needed). Error handling and control flow unchanged.
Test utility temp files test/util/rotate.go	Replace ioutil.TempFile with os.CreateTemp; remove ioutil import. Surrounding logic preserved.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

✨ Finishing Touches

• 📝 Generate docstrings

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment

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[openshift-ci]

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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.

[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	882c6f7	link	true	/test e2e-aws
ci/prow/e2e-aws-operator	882c6f7	link	true	/test e2e-aws-operator
ci/prow/e2e-aws-operator-serial-ote	882c6f7	link	false	/test e2e-aws-operator-serial-ote

Full PR test history. Your PR dashboard.

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