Avoid instantiating things via init()

[antoineco]

Rationale

Init functions cause imports to have side effects. Side effects are hard to test, reduce readability and increase the complexity of the code.

There are a few places where they prevent us from handling errors properly too:

kraftkit/oci/oci.go

Lines 22 to 25 in 8d4f1a1

	// FIXME(antoineco): avoid init, initialize things where needed
	func init() {
	// Register a new pkg.Package type
	_ = packmanager.RegisterPackageManager(OCIFormat, NewOCIManager)

Describe alternatives

Instantiate package managers in one place. Don't use globals. Constructors can still live in their own packages.

Register flags centrally and explicitly. If flag definitions need to exist in different packages, simply request them using a public getter.

Interesting read: https://peter.bourgon.org/blog/2017/06/09/theory-of-modern-go.html

Related architectures

None

Related platforms

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Additional context

No response