Upgrade to latest version of kubebuilder (#29)

* controller: move custom logic to another file

This makes it easier to upgrade kubebuilder, as kubebuilder upgrade
requires to manually update the file or regenerate them with the CLI and
integrating our own change in them.

* misc: upgrade to latest version of kubebuilder

- Stop using operator-sdk, as we don't use any of the additional feature
  and it makes it harder to upgrade
- Switch to go/v4 plugin[1]: this change a bit the layout of the
  project. go/v4 is the only supported version and ensure that we will
  support newer version of Go and Kubernetes.
- Enabling the pprof endpoint is now directly part of the manager
- Namespace cannot be specified anymore. This makes the controller watch
  for the CRD in all namespaces. Future changes are needed to support
  managing multiple clusters from the same controller.
- Upgrade gohbase to the latest version available.

[1] https://book.kubebuilder.io/migration/v3vsv4#tldr-of-the-new-gov4-plugin

* controller: fix some linting warning

* cmd/main: add back the --namespace flag

.dockerignore

@@ -0,0 +1,3 @@
+# More info: https://docs.docker.com/engine/reference/builder/#dockerignore-file
+# Ignore build and test binaries.
+bin/

.gitignore

@@ -1,26 +1,27 @@
-
 # Binaries for programs and plugins
 *.exe
 *.exe~
 *.dll
 *.so
 *.dylib
-bin
+bin/*
+Dockerfile.cross
 
-# Test binary, build with `go test -c`
+# Test binary, built with `go test -c`
 *.test
 
 # Output of the go coverage tool, specifically when used with LiteIDE
 *.out
 
-# Kubernetes Generated files - skip generated files, except for vendored files
+# Go workspace file
+go.work
 
+# Kubernetes Generated files - skip generated files, except for vendored files
 !vendor/**/zz_generated.*
 
 # editor and IDE paraphernalia
 .idea
+.vscode
 *.swp
 *.swo
 *~
-
-testbin/*

.golangci.yml

@@ -0,0 +1,40 @@
+run:
+  deadline: 5m
+  allow-parallel-runners: true
+
+issues:
+  # don't skip warning about doc comments
+  # don't exclude the default set of lint
+  exclude-use-default: false
+  # restore some of the defaults
+  # (fill in the rest as needed)
+  exclude-rules:
+    - path: "api/*"
+      linters:
+        - lll
+    - path: "internal/*"
+      linters:
+        - dupl
+        - lll
+linters:
+  disable-all: true
+  enable:
+    - dupl
+    - errcheck
+    - exportloopref
+    - goconst
+    - gocyclo
+    - gofmt
+    - goimports
+    - gosimple
+    - govet
+    - ineffassign
+    - lll
+    - misspell
+    - nakedret
+    - prealloc
+    - staticcheck
+    - typecheck
+    - unconvert
+    - unparam
+    - unused

Dockerfile

@@ -1,5 +1,5 @@
 # Build the manager binary
-FROM golang:1.19 as builder
+FROM golang:1.21 AS builder
 ARG TARGETOS
 ARG TARGETARCH
 
@@ -12,16 +12,16 @@ COPY go.sum go.sum
 RUN go mod download
 
 # Copy the go source
-COPY main.go main.go
+COPY cmd/main.go cmd/main.go
 COPY api/ api/
-COPY controllers/ controllers/
+COPY internal/controller/ internal/controller/
 
 # Build
 # the GOARCH has not a default value to allow the binary be built according to the host where the command
 # was called. For example, if we call make docker-build in a local env which has the Apple Silicon M1 SO
 # the docker BUILDPLATFORM arg will be linux/arm64 when for Apple x86 it will be linux/amd64. Therefore,
 # by leaving it empty we can ensure that the container and binary shipped on it will have the same platform.
-RUN CGO_ENABLED=0 GOOS=${TARGETOS:-linux} GOARCH=${TARGETARCH} go build -a -o manager main.go
+RUN CGO_ENABLED=0 GOOS=${TARGETOS:-linux} GOARCH=${TARGETARCH} go build -a -o manager cmd/main.go
 
 # Use distroless as minimal base image to package the manager binary
 # Refer to https://github.com/GoogleContainerTools/distroless for more details