Add Go operator (#7)

This is the 1st version of the operator written in Go. Using these operator, users can interact with the cluster. The operator consists of CustomResource, represented by CustomResourceDefinition and controller loop, also called reconciliation loop. Coordinators and data instances are created as StatefulSets. Each coordinator and data instance have two services attached to it, ClusterIP and NodePort. ClusterIP is used for internal communication between instances and NodePort for external access to the Bolt server. Controller tests are deleted since they weren't used. Setup job runs as Deployment. License and organization name should be user-provided in the form of Kubernetes Secret.

Author: as51340

.dockerignore

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

.github/CODEOWNERS

@@ -0,0 +1 @@
+as51340

.gitignore

@@ -12,3 +12,5 @@ bin
 *.swp
 *.swo
 *~
+
+./manager

.gitmodules

@@ -1,4 +1,4 @@
 [submodule "helm-charts"]
 	path = helm-charts
-  url = https://github.com/memgraph/helm-charts.git
+	url = https://github.com/memgraph/helm-charts.git
   branch = main

.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

.pre-commit-config.yaml

@@ -1,6 +1,6 @@
 repos:
 - repo: https://github.com/pre-commit/pre-commit-hooks
-  rev: v4.5.0
+  rev: v4.6.0
   hooks:
   - id: trailing-whitespace
   - id: end-of-file-fixer
@@ -10,3 +10,9 @@ repos:
   - id: mixed-line-ending
   - id: check-merge-conflict
   - id: detect-private-key
+
+- repo: https://github.com/tekwizely/pre-commit-golang
+  rev: v1.0.0-rc.1
+  hooks:
+  -   id: go-mod-tidy
+  -   id: go-fmt

Dockerfile

@@ -1,7 +1,33 @@
 # Build the manager binary
-FROM quay.io/operator-framework/helm-operator:v1.35.0
+FROM golang:1.22 AS builder
+ARG TARGETOS
+ARG TARGETARCH
 
-ENV HOME=/opt/helm
-COPY watches.yaml ${HOME}/watches.yaml
-COPY helm-charts  ${HOME}/helm-charts
-WORKDIR ${HOME}
+WORKDIR /workspace
+# Copy the Go Modules manifests
+COPY go.mod go.mod
+COPY go.sum go.sum
+# cache deps before building and copying source so that we don't need to re-download as much
+# and so that source changes don't invalidate our downloaded layer
+RUN go mod download
+
+# Copy the go source
+COPY cmd/main.go cmd/main.go
+COPY api/ api/
+COPY internal/controller/ internal/controller/
+
+# Build
+# the GOARCH has not a default value to allow the binary be built according to the host where the command
+# was called. For example, if we call make docker-build in a local env which has the Apple Silicon M1 SO
+# the docker BUILDPLATFORM arg will be linux/arm64 when for Apple x86 it will be linux/amd64. Therefore,
+# by leaving it empty we can ensure that the container and binary shipped on it will have the same platform.
+RUN CGO_ENABLED=0 GOOS=${TARGETOS:-linux} GOARCH=${TARGETARCH} go build -a -o manager cmd/main.go
+
+# Use distroless as minimal base image to package the manager binary
+# Refer to https://github.com/GoogleContainerTools/distroless for more details
+FROM gcr.io/distroless/static:nonroot
+WORKDIR /
+COPY --from=builder /workspace/manager .
+USER 65532:65532
+
+ENTRYPOINT ["/manager"]