[APP-4166] New Subsystem

.golangci.yaml

@@ -0,0 +1,89 @@
+service:
+  golangci-lint-version: 1.55.2
+run:
+  deadline: 900s
+  modules-download-mode: readonly
+  tests: true
+linters:
+  enable-all: true
+  disable:
+    - asasalint
+    - containedctx
+    - contextcheck
+    - cyclop
+    - deadcode
+    - depguard
+    - exhaustivestruct
+    - exhaustruct
+    - forcetypeassert
+    - funlen
+    - gocognit
+    - godox
+    - goerr113
+    - gochecknoglobals
+    - gochecknoinits
+    - gocyclo
+    - gofmt
+    - goimports
+    - golint
+    - gomnd
+    - ifshort
+    - importas
+    - interfacebloat
+    - interfacer
+    - ireturn
+    - maintidx
+    - maligned
+    - makezero
+    - musttag
+    - nestif
+    - nlreturn
+    - nosnakecase
+    - nonamedreturns
+    - nosprintfhostport
+    - paralleltest
+    - prealloc
+    - revive
+    - scopelint
+    - structcheck
+    - tagliatelle
+    - testpackage
+    - thelper # false positives
+    - varcheck
+    - varnamelen
+    - wrapcheck
+    - wsl
+linters-settings:
+  errcheck:
+    check-blank: true
+  gci:
+    sections:
+      - standard
+      - default
+      - prefix(github.com/viamrobotics/agent-syscfg)
+  gofumpt:
+    lang-version: "1.21"
+    extra-rules: true
+  govet:
+    enable-all: true
+    disable:
+      - fieldalignment
+      - shadow
+      - composites
+  lll:
+    line-length: 140
+issues:
+  exclude-rules:
+    - path: _test\.go$
+      linters:
+        - dupword
+        - errcheck
+        - exhaustive
+        - goconst
+        - gosec
+    - path: ^cmd/client/
+      linters:
+        - forbidigo
+  exclude-use-default: false
+  max-per-linter: 0
+  max-same-issues: 0

Makefile

@@ -0,0 +1,52 @@
+GOOS ?= "linux"
+GOARCH ?= $(shell go env GOARCH)
+ifeq ($(GOARCH),amd64)
+LINUX_ARCH = x86_64
+else ifeq ($(GOARCH),arm64)
+LINUX_ARCH = aarch64
+endif
+
+GIT_REVISION = $(shell git rev-parse HEAD | tr -d '\n')
+TAG_VERSION ?= $(shell git tag --points-at | sort -Vr | head -n1 | cut -c2-)
+ifeq ($(TAG_VERSION),)
+PATH_VERSION = custom
+else
+PATH_VERSION = v$(TAG_VERSION)
+endif
+
+LDFLAGS = "-s -w -X 'github.com/viamrobotics/agent-syscfg.Version=${TAG_VERSION}' -X 'github.com/viamrobotics/agent-syscfg.GitRevision=${GIT_REVISION}'"
+TAGS = osusergo,netgo
+
+.DEFAULT_GOAL := bin/viam-agent-syscfg-$(PATH_VERSION)-$(LINUX_ARCH)
+
+.PHONY: all
+all: amd64 arm64
+
+.PHONY: arm64
+arm64:
+	make GOARCH=arm64
+
+.PHONY: amd64
+amd64:
+	make GOARCH=amd64
+
+bin/viam-agent-syscfg-$(PATH_VERSION)-$(LINUX_ARCH): go.* *.go */*/*.go
+	go build -o $@ -tags $(TAGS) -ldflags $(LDFLAGS) ./cmd/viam-agent-syscfg/main.go
+	test "$(PATH_VERSION)" != "custom" && cp $@ bin/viam-agent-syscfg-stable-$(LINUX_ARCH) || true
+
+.PHONY: clean
+clean:
+	rm -rf bin/
+
+bin/golangci-lint:
+	GOBIN=`pwd`/bin go install github.com/golangci/golangci-lint/cmd/[email protected]
+
+.PHONY: lint
+lint: bin/golangci-lint
+	go mod tidy
+	bin/golangci-lint run -v --fix
+
+.PHONY: upload-stable
+upload-stable: bin/viam-agent-syscfg-$(PATH_VERSION)-x86_64 bin/viam-agent-syscfg-$(PATH_VERSION)-aarch64 bin/viam-agent-syscfg-stable-x86_64 bin/viam-agent-syscfg-stable-aarch64
+	test "$(PATH_VERSION)" != "custom"
+	gsutil -h "Cache-Control:no-cache" cp bin/viam-agent-syscfg-$(PATH_VERSION)-x86_64 bin/viam-agent-syscfg-$(PATH_VERSION)-aarch64 bin/viam-agent-syscfg-stable-x86_64 bin/viam-agent-syscfg-stable-aarch64 gs://packages.viam.com/apps/viam-agent-syscfg/

README.md

@@ -1,2 +1,26 @@
 # Agent Syscfg
 This is a subsystem (plugin) for the viam-agent that provides a number of system/os configuration helpers.
+
+## Current Options
+Parameters are set via the `attributes` object of the agent-syscfg object in the agent config (currently via "Raw JSON" editor in https://app.viam.com/ )
+
+Configuration is split into sections, each of which will control a different area of system management and/or configuration. Currently only logging control is available.
+
+### Logging
+Two parameters can be set for logging control. `system_max_use` and `runtime_max_use` The first sets the maximum disk space journald will user for persistent log storage. The second, the runtime/temporary limit. Both of these will be configured to 512M by default if not set. Numeric values are in bytes, with optional single letter suffix for larger units, e.g. K, M, or G.
+There is also `disable` which may be set to `true` to remove any prior tweaks to the logging config and disable the use of defaults.
+
+## Example Config
+
+```json
+"agent-syscfg": {
+	"release_channel": "stable",
+	"attributes": {
+		"logging": {
+			"disable": true,
+			"system_max_use": "128M",
+			"runtime_max_use": "96M"
+		}
+	}
+}
+```

cmd/viam-agent-syscfg/main.go

@@ -0,0 +1,135 @@
+package main
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"os"
+	"os/signal"
+	"sync"
+	"sync/atomic"
+	"syscall"
+	"time"
+
+	"github.com/edaniels/golog"
+	"github.com/jessevdk/go-flags"
+
+	syscfg "github.com/viamrobotics/agent-syscfg"
+)
+
+var (
+	// only changed/set at startup, so no mutex.
+	log                     = golog.NewDevelopmentLogger("agent-syscfg")
+	activeBackgroundWorkers sync.WaitGroup
+)
+
+func main() {
+	var opts struct {
+		Config  string `default:"/opt/viam/etc/agent-syscfg.json" description:"Path to config file" long:"config" short:"c"`
+		Debug   bool   `description:"Enable debug logging"        long:"debug"                      short:"d"`
+		Help    bool   `description:"Show this help message"      long:"help"                       short:"h"`
+		Version bool   `description:"Show version"                long:"version"                    short:"v"`
+	}
+
+	parser := flags.NewParser(&opts, flags.IgnoreUnknown)
+	parser.Usage = "runs as a background service and manages updates and the process lifecycle for viam-server."
+
+	_, err := parser.Parse()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	if opts.Help {
+		var b bytes.Buffer
+		parser.WriteHelp(&b)
+		//nolint:forbidigo
+		fmt.Println(b.String())
+		return
+	}
+
+	if opts.Version {
+		//nolint:forbidigo
+		fmt.Printf("Version: %s\nGit Revision: %s\n", syscfg.GetVersion(), syscfg.GetRevision())
+		return
+	}
+
+	if opts.Debug {
+		log = golog.NewDebugLogger("agent-syscfg")
+	}
+
+	ctx := setupExitSignalHandling()
+	defer activeBackgroundWorkers.Wait()
+
+	cfg, err := syscfg.LoadConfig(opts.Config)
+	if err != nil {
+		log.Warn(err)
+	}
+
+	log.Debugf("Config: %+v", cfg)
+	// core one-shot functions start
+
+	// set journald max size limits
+	syscfg.EnforceLogging(cfg.Logging, log)
+
+	// core one-shot functions end
+
+	// exact text "startup complete" is important, the parent process will watch for this line to indicate startup is successful
+	log.Info("agent-syscfg startup complete")
+
+	// do nothing forever, just respond to health checks
+	for {
+		if !syscfg.HealthySleep(ctx, time.Minute) {
+			break
+		}
+		// future tweaks that require regular checks/updates/etc (non one-shots) will go here
+	}
+
+	log.Info("agent-syscfg subsystem exiting")
+}
+
+func setupExitSignalHandling() context.Context {
+	ctx, cancel := context.WithCancel(context.Background())
+	sigChan := make(chan os.Signal, 16)
+
+	healthcheckRequest := &atomic.Bool{}
+	ctx = context.WithValue(ctx, syscfg.HCReqKey, healthcheckRequest)
+
+	activeBackgroundWorkers.Add(1)
+	go func() {
+		defer activeBackgroundWorkers.Done()
+		defer cancel()
+		for {
+			sig := <-sigChan
+			switch sig {
+			// things we exit for
+			case os.Interrupt:
+				fallthrough
+			case syscall.SIGQUIT:
+				fallthrough
+			case syscall.SIGABRT:
+				fallthrough
+			case syscall.SIGTERM:
+				log.Info("exit signal received")
+				signal.Ignore(os.Interrupt, syscall.SIGTERM, syscall.SIGABRT) // keeping SIGQUIT for stack trace debugging
+				return
+
+			// this will eventually be handled elsewhere as a restart, not exit
+			case syscall.SIGHUP:
+
+			// ignore SIGURG entirely, it's used for real-time scheduling notifications
+			case syscall.SIGURG:
+
+			// used by parent viam-agent for healthchecks
+			case syscall.SIGUSR1:
+				healthcheckRequest.Store(true)
+
+			// log everything else
+			default:
+				log.Debugw("received unknown signal", "signal", sig)
+			}
+		}
+	}()
+
+	signal.Notify(sigChan, os.Interrupt, syscall.SIGTERM, syscall.SIGABRT, syscall.SIGUSR1)
+	return ctx
+}

go.mod

@@ -0,0 +1,18 @@
+module github.com/viamrobotics/agent-syscfg
+
+go 1.21.4
+
+require (
+	github.com/edaniels/golog v0.0.0-20230215213219-28954395e8d0
+	github.com/jessevdk/go-flags v1.5.0
+	github.com/pkg/errors v0.9.1
+	github.com/sergeymakinen/go-systemdconf/v2 v2.0.2
+	go.uber.org/zap v1.23.0
+)
+
+require (
+	github.com/benbjohnson/clock v1.1.0 // indirect
+	go.uber.org/atomic v1.7.0 // indirect
+	go.uber.org/multierr v1.6.0 // indirect
+	golang.org/x/sys v0.5.0 // indirect
+)