Basic outline (#1)

Adds project layout and basic functionality of the consul-dataplane process.

Author: jshahriddhi

.github/workflows/consul-dataplane-checks.yaml

@@ -0,0 +1,28 @@
+name: consul-dataplane-checks
+
+on:
+  push:
+    branches:
+      main
+  pull_request:
+
+jobs:
+  unit-tests:
+    name: unit-tests
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-go@v3
+        with:
+          go-version: '1.18'
+      - run: go test ./...
+  golangci:
+    name: lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/setup-go@v3
+        with:
+          go-version: 1.18
+      - uses: actions/checkout@v3
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@v3

.gitignore

@@ -0,0 +1,2 @@
+cmd/consul-dataplane/main
+/consul-dataplane

buf.gen.yaml

@@ -0,0 +1,14 @@
+version: v1
+managed:
+  enabled: true
+  go_package_prefix:
+    default: github.com/hashicorp/consul-dataplane/internal/consul-proto
+plugins:
+  - name: go
+    out: internal/consul-proto
+    opt:
+      - paths=source_relative
+  - name: go-grpc
+    out: internal/consul-proto
+    opt:
+      - paths=source_relative

cmd/consul-dataplane/main.go

@@ -0,0 +1,67 @@
+package main
+
+import (
+	"context"
+	"flag"
+	"log"
+	"strings"
+
+	"github.com/hashicorp/consul-dataplane/pkg/consuldp"
+)
+
+var (
+	addresses string
+	grpcPort  int
+	logLevel  string
+	logJSON   bool
+)
+
+func init() {
+	flag.StringVar(&addresses, "addresses", "", "Consul server addresses. Value can be:\n"+
+		"1. DNS name (that resolves to servers or DNS name of a load-balancer front of Consul servers); OR\n"+
+		"2.'exec=<executable with optional args>'. The executable\n"+
+		"	a) on success - should exit 0 and print to stdout whitespace delimited IP (v4/v6) addresses\n"+
+		"	b) on failure - exit with a non-zero code and optionally print an error message of upto 1024 bytes to stderr.\n"+
+		"	Refer to https://github.com/hashicorp/go-netaddrs#summary for more details and examples.")
+
+	flag.IntVar(&grpcPort, "grpc-port", 8502, "gRPC port on Consul servers")
+
+	flag.StringVar(&logLevel, "log-level", "info", "Log level of the messages to print. "+
+		"Available log levels are \"trace\", \"debug\", \"info\", \"warn\", and \"error\".")
+
+	flag.BoolVar(&logJSON, "log-json", false, "Controls consul-dataplane logging in JSON format. By default this is false.")
+}
+
+// validateFlags performs semantic validation of the flag values
+func validateFlags() {
+	switch strings.ToUpper(logLevel) {
+	case "TRACE", "DEBUG", "INFO", "WARN", "ERROR":
+	default:
+		log.Fatal("invalid log level. valid values - TRACE, DEBUG, INFO, WARN, ERROR")
+	}
+}
+
+func main() {
+
+	flag.Parse()
+
+	validateFlags()
+
+	consuldpCfg := &consuldp.Config{
+		Consul: &consuldp.ConsulConfig{Addresses: addresses, GRPCPort: grpcPort},
+		Logging: &consuldp.LoggingConfig{
+			Name:     "consul-dataplane",
+			LogLevel: strings.ToUpper(logLevel),
+			LogJSON:  logJSON,
+		},
+	}
+	consuldpInstance, err := consuldp.NewConsulDP(consuldpCfg)
+	if err != nil {
+		log.Fatal(err)
+	}
+	// TODO: Pass cancellable context
+	err = consuldpInstance.Run(context.Background())
+	if err != nil {
+		log.Fatal(err)
+	}
+}

go.mod

@@ -0,0 +1,27 @@
+module github.com/hashicorp/consul-dataplane
+
+go 1.18
+
+require (
+	github.com/hashicorp/go-hclog v1.2.2
+	github.com/hashicorp/go-netaddrs v0.0.0-20220509001840-90ed9d26ec46
+	github.com/stretchr/testify v1.8.0
+	google.golang.org/grpc v1.48.0
+	google.golang.org/protobuf v1.28.1
+)
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/fatih/color v1.13.0 // indirect
+	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/google/go-cmp v0.5.8 // indirect
+	github.com/mattn/go-colorable v0.1.12 // indirect
+	github.com/mattn/go-isatty v0.0.14 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/stretchr/objx v0.4.0 // indirect
+	golang.org/x/net v0.0.0-20220624214902-1bab6f366d9e // indirect
+	golang.org/x/sys v0.0.0-20220624220833-87e55d714810 // indirect
+	golang.org/x/text v0.3.7 // indirect
+	google.golang.org/genproto v0.0.0-20220624142145-8cd45d7dbd1f // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)