[doc]: https://github.com/golang/go/wiki/Modules#releasing-modules-v2-or-higher
Per this Go modules [doc] a repo or branch that's
already tagged v2 or higher should increment the major
version (e.g. go to v3) when releasing their first Go
module-based packages.
At the moment, the kustomize repo has these top level
packages in the sigs.k8s.io/kustomize module:
- `cmd` - holds main program for kustomize
Conceivably someone can depend on this
package for integration tests.
- `internal` - intentionally unreleased subpackages
- `k8sdeps` - an adapter wrapping k8s dependencies
This exists only for use in pre-Go-modules kustomize-into-kubectl
integration and won't live much longer (as everything involved is
switching to Go modules).
- `pkg` - kustomize packages for export
This should shrink in later versions, since
the surface area is too large, containing
sub-packages that should be in 'internal'.
- `plugin` - holds main programs for plugins
This PR changes the top level go.mod file from
```
module sigs.k8s.io/kustomize
```
to
```
module sigs.k8s.io/kustomize/v3
```
and adjusts all import statements to
reflect the change.
This commit changes git/cloner.go from cloning the whole history
and then checking out the desired ref to a implementation that
only downloads the history for the desired ref.
It does so by first initializing an empty repository, setting the
source repository as a remote, fetching just the desired ref and
then hard resetting the empty local repo to that ref.
This reduces the time it takes to build the multibases example
as a remote base at ref v2.0.3 from an avg of 8s with the
current implementation to an avg of 2s out of 10 runs each, by
drastically decreasing the data transferred.
The improvement should increase as repositories grow.
This PR closes a TODO in the fileLoader type to
replace the string representing a git repo url
with a struct called holding validated fields.
New struct is called RepoSpec.
It holds what we need in coming PRs for remote
repo base containment checks, and will also allow
the overlay cycle prevention code to take into
account different host schemes or branches.
The struct is in a new file called repospec.go.
The new file is mostly just a code move of url
parsing code that was in cloner.go. Git "blame"
history preserved through the move.
No change in execution (see final commit by itself).
