go: preparing the CLI interface

go.mod

@@ -14,6 +14,7 @@ require (
 	github.com/go-faster/errors v0.7.1
 	github.com/go-faster/jx v1.1.0
 	github.com/jaswdr/faker/v2 v2.3.0
+	github.com/joho/godotenv v1.5.1
 	github.com/knadh/koanf/parsers/json v0.1.0
 	github.com/knadh/koanf/parsers/yaml v0.1.0
 	github.com/knadh/koanf/providers/confmap v0.1.0

go.sum

@@ -98,6 +98,8 @@ github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2
 github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
 github.com/jaswdr/faker/v2 v2.3.0 h1:jgQ9UmU2Eb5tSQ8JkUS4tPoyTM2OtThQpOpwk7Fa9RY=
 github.com/jaswdr/faker/v2 v2.3.0/go.mod h1:ROK8xwQV0hYOLDUtxCQgHGcl10jbVzIvqHxcIDdwY2Q=
+github.com/joho/godotenv v1.5.1 h1:7eLL/+HRGLY0ldzfGMeQkb7vMd0as4CfYvUVzLqw0N0=
+github.com/joho/godotenv v1.5.1/go.mod h1:f4LDr5Voq0i2e/R5DDNOoa2zzDfwtkZa6DnEwAbqwq4=
 github.com/knadh/koanf/maps v0.1.1 h1:G5TjmUh2D7G2YWf5SQQqSiHRJEjaicvU0KpypqB3NIs=
 github.com/knadh/koanf/maps v0.1.1/go.mod h1:npD/QZY3V6ghQDdcQzl1W4ICNVTkohC8E73eI2xW4yI=
 github.com/knadh/koanf/parsers/json v0.1.0 h1:dzSZl5pf5bBcW0Acnu20Djleto19T0CfHcvZ14NJ6fU=

go/cmd/bluemage/main.go

@@ -2,11 +2,16 @@ package main
 
 import (
 	"context"
+	"fmt"
+	"log/slog"
 	"os"
 	"os/signal"
 
+	"github.com/adrg/xdg"
+	"github.com/joho/godotenv"
 	"github.com/spf13/cobra"
 	"github.com/tigorlazuardi/bluemage/go/cmd/bluemage/serve"
+	"github.com/tigorlazuardi/bluemage/go/config"
 )
 
 var Cmd = &cobra.Command{
@@ -16,12 +21,54 @@ var Cmd = &cobra.Command{
 
 func init() {
 	Cmd.AddCommand(serve.Cmd)
+
+	flags := Cmd.PersistentFlags()
+	for _, entry := range config.DefaultConfig {
+		key, value, desc, hidden := entry.Key, entry.Value, entry.Desc, entry.Hidden
+		switch v := value.(type) {
+		case bool:
+			flags.Bool(key, v, desc)
+		case string:
+			flags.String(key, v, desc)
+		case int:
+			flags.Int(key, v, desc)
+		case float32:
+			flags.Float32(key, v, desc)
+		case float64:
+			flags.Float64(key, v, desc)
+		default:
+			flags.String(key, fmt.Sprintf("%v", v), desc)
+		}
+		if hidden {
+			flags.MarkHidden(key)
+		}
+	}
 }
 
 func main() {
+	_ = godotenv.Load()
+
+	xdgJson, _ := xdg.ConfigFile("bluemage/config.json")
+	xdgYaml, _ := xdg.ConfigFile("bluemage/config.yaml")
+
+	cfg, err := config.NewConfigBuilder().
+		LoadDefault().
+		LoadJSONFile("/etc/bluemage/config.json").
+		LoadYamlFile("/etc/bluemage/config.yaml").
+		LoadJSONFile(xdgJson).
+		LoadYamlFile(xdgYaml).
+		LoadJSONFile("config.json").
+		LoadYamlFile("config.yaml").
+		LoadEnv().
+		LoadFlags(Cmd.PersistentFlags()).
+		BuildHandle()
+	if err != nil {
+		slog.Error("BLUEMAGE: failed to load config", "error", err)
+		os.Exit(1)
+	}
 	ctx, cancel := signal.NotifyContext(context.Background(), os.Interrupt)
 	defer cancel()
-
+	ctx = config.WithContext(ctx, cfg)
 	if err := Cmd.ExecuteContext(ctx); err != nil {
 		os.Exit(1)
 	}

go/cmd/bluemage/serve/serve.go

@@ -4,7 +4,9 @@ import (
 	"context"
 	"database/sql"
 	"errors"
+	"fmt"
 	"log/slog"
+	"net"
 	"net/http"
 	"os"
 	"time"
@@ -15,6 +17,7 @@ import (
 	"github.com/spf13/cobra"
 	"github.com/stephenafamo/bob"
 	"github.com/tigorlazuardi/bluemage/go/api"
+	"github.com/tigorlazuardi/bluemage/go/config"
 	"github.com/tigorlazuardi/bluemage/go/gen/proto/device/v1/v1connect"
 	"github.com/tigorlazuardi/bluemage/go/pkg/errs"
 	"github.com/tigorlazuardi/bluemage/go/pkg/log"
@@ -26,9 +29,22 @@ import (
 var Cmd = &cobra.Command{
 	Use: "serve",
 	RunE: func(cmd *cobra.Command, args []string) error {
-		sqldb, err := sql.Open("sqlite3", "file:data.db")
+		ctx := cmd.Context()
+		cfg := config.FromContext(ctx)
+		logOutput := log.WrapOsFile(os.Stderr)
+		prettyHandler := log.NewPrettyHandler(logOutput, nil)
+		slog.SetDefault(slog.New(prettyHandler))
+
+		if err := os.MkdirAll(cfg.String("download.directory"), 0755); err != nil {
+			return errs.Wrapw(err, "failed to create download directory", "path", cfg.String("download.directory"))
+		}
+
+		sqldb, err := sql.Open(cfg.String("db.driver"), fmt.Sprintf("file:%s", cfg.String("db.path")))
 		if err != nil {
-			return errs.Wrapw(err, "failed to open database", "file", "data.db")
+			return errs.Wrapw(err, "failed to open database",
+				"driver", cfg.String("db.driver"),
+				"dsn", cfg.String("db.dsn"),
+			)
 		}
 
 		sqldb = sqldblogger.OpenDriver(
@@ -38,9 +54,6 @@ var Cmd = &cobra.Command{
 			sqldblogger.WithSQLQueryAsMessage(true),
 		)
 		db := bob.New(sqldb)
-		logOutput := log.WrapOsFile(os.Stderr)
-		prettyHandler := log.NewPrettyHandler(logOutput, nil)
-		slog.SetDefault(slog.New(prettyHandler))
 
 		api := &api.API{
 			DB: db,
@@ -64,12 +77,15 @@ var Cmd = &cobra.Command{
 		)))
 
 		server := &http.Server{
-			Addr:    ":8080",
+			Addr:    fmt.Sprintf("%s:%s", cfg.String("http.host"), cfg.String("http.port")),
 			Handler: h2c.NewHandler(server.WithCORS(mux), &http2.Server{}),
+			BaseContext: func(net.Listener) context.Context {
+				return ctx
+			},
 		}
 
 		go func() {
-			<-cmd.Context().Done()
+			<-ctx.Done()
 			slog.Info("Exit signal received. Shutting down server")
 			shutdownCtx, cancel := context.WithTimeout(context.Background(), time.Second*5)
 			defer cancel()
@@ -86,3 +102,6 @@ var Cmd = &cobra.Command{
 	},
 	SilenceUsage: true,
 }
+
+func Register(cmd *cobra.Command, config *config.Config) {
+}

go/config/builder.go

@@ -33,7 +33,7 @@ func (builder *ConfigBuilder) BuildHandle() (*Config, error) {
 }
 
 func (builder *ConfigBuilder) LoadDefault() *ConfigBuilder {
-	provider := confmap.Provider(DefaultConfig, ".")
+	provider := confmap.Provider(DefaultConfig.ToMap(), ".")
 
 	err := builder.koanf.Load(provider, nil)
 	if err != nil {

go/config/context.go

@@ -0,0 +1,20 @@
+package config
+
+import "context"
+
+type contextKey struct{}
+
+var key = contextKey{}
+
+// WithContext returns a new context with the given Config.
+func WithContext(ctx context.Context, cfg *Config) context.Context {
+	return context.WithValue(ctx, key, cfg)
+}
+
+// FromContext returns the Config from the given context.
+//
+// Returns nil if the Config is not found.
+func FromContext(ctx context.Context) *Config {
+	cfg, _ := ctx.Value(key).(*Config)
+	return cfg
+}

go/config/default.go

@@ -2,61 +2,69 @@ package config
 
 import (
 	"path"
-	"time"
 
 	"github.com/adrg/xdg"
 )
 
 var Version string = "unknown"
 
-var DefaultConfig = map[string]any{
+type Entry struct {
-	"flags.containerized": false,
+	Key    string
-
+	Value  any
-	"log.enable":      true,
+	Desc   string
-	"log.level":       "info",
+	Hidden bool
-	"log.output":      "stderr",
+}
-	"log.file.enable": true,
+
-	"log.file.path":   path.Join(xdg.CacheHome, "bluemage", "bluemage.log"),
+type Entries []Entry
-
+
-	"db.driver": "sqlite3",
+func (e Entries) ToMap() map[string]any {
-	"db.string": path.Join(xdg.Home, ".local", "share", "bluemage", "data.db"),
+	m := make(map[string]any, len(e))
-
+	for _, entry := range e {
-	"pubsub.db.name":      path.Join(xdg.Home, ".local", "share", "bluemage", "pubsub.db"),
+		m[entry.Key] = entry.Value
-	"pubsub.db.timeout":   "5s",
+	}
-	"pubsub.ack.deadline": "30m",
+	return m
-
+}
-	"download.concurrency.images":     5,
+
-	"download.concurrency.subreddits": 3,
+var DefaultConfig = Entries{
-
+	{"log.file.enable", true, "Enable file logging", false},
-	"download.directory":         path.Join(xdg.UserDirs.Pictures, "bluemage"),
+	{"log.level", "info", `Log level. Possible values: "debug", "info", "warn", "error"`, false},
-	"download.timeout.headers":   "10s",
+	{"log.output", "stderr", "Log output. Possible values: \"stdout\", \"stderr\"", false},
-	"download.timeout.idle":      "5s",
+	{"log.file.path", path.Join(xdg.CacheHome, "bluemage", "bluemage.log"), "Log file path", false},
-	"download.timeout.idlespeed": "10KB",
+
-	"download.useragent":         "bluemage/v1",
+	{"db.driver", "sqlite3", "Database driver", false},
-
+	{"db.path", path.Join(xdg.Home, ".local", "share", "bluemage", "data.db"), "Database path", false},
-	"http.port":             "8080",
+
-	"http.host":             "0.0.0.0",
+	{"pubsub.db.path", path.Join(xdg.Home, ".local", "share", "bluemage", "pubsub.db"), "PubSub database path", false},
-	"http.shutdown_timeout": "5s",
+	{"pubsub.db.timeout", "5s", "PubSub database timeout", false},
-
+	{"pubsub.ack.deadline", "30m", "PubSub ack deadline", false},
-	"telemetry.openobserve.enable":             false,
+
-	"telemetry.openobserve.log.enable":         true,
+	{"download.concurrency", 5, "Number of concurrent image downloads", false},
-	"telemetry.openobserve.log.level":          "info",
+	{"download.directory", path.Join(xdg.UserDirs.Pictures, "bluemage"), "Download directory", false},
-	"telemetry.openobserve.log.source":         true,
+	{"download.timeout.headers", "10s", "How long to wait for Reddit to response with data after opening connection. To prevent download connection getting clogged up for too long", false},
-	"telemetry.openobserve.log.endpoint":       "http://localhost:5080/api/default/default/_json",
+	{"download.timeout.idle", "5s", "Download idle timeout. Whenever a download speed is under idlespeed for this duration, the download is cancelled. To prevent slow download speed from clogging up the queue", false},
-	"telemetry.openobserve.log.concurrency":    4,
+	{"download.timeout.idlespeed", "10KB", "Threshold for the download speed to be considered 'idle'", false},
-	"telemetry.openobserve.log.buffer.size":    2 * 1024, // 2kb
+	{"download.useragent", "bluemage/v1", "Download user agent. Must not be empty. Avoid common user agent values like 'curl'", false},
-	"telemetry.openobserve.log.buffer.timeout": "2s",
+
-	"telemetry.openobserve.log.username":       "root@example.com",
+	{"http.port", "8080", "HTTP server port", false},
-	"telemetry.openobserve.log.password":       "Complexpass#123",
+	{"http.host", "0.0.0.0", "HTTP server host", false},
-
+	{"http.shutdown_timeout", "5s", "Timeout to wait closing i/o connections until the server force closes everything", false},
-	"telemetry.openobserve.trace.enable": true,
+
-	"telemetry.openobserve.trace.url":    "http://localhost:5080/api/default/v1/traces",
+	{"telemetry.openobserve.enable", false, "Wether to enable telemetry support to OpenObserve server. Setting this to false, disables all other 'telemetry.openobserve' options (default false)", false},
-	"telemetry.openobserve.trace.auth":   "Basic AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA",
+	{"telemetry.openobserve.log.enable", true, "Wether to enable logging telemetry to OpenObserve server", false},
-
+	{"telemetry.openobserve.log.level", "info", "Log level for telemetry logging", false},
-	"telemetry.trace.ratio": 1,
+	{"telemetry.openobserve.log.source", true, "Wether to include source code in the log", false},
-
+	{"telemetry.openobserve.log.endpoint", "http://localhost:5080/api/default/default/_json", "OpenObserve log endpoint", false},
-	"runtime.version":     Version,
+	{"telemetry.openobserve.log.concurrency", 4, "Number of allowed concurrent connections to send logs to the server", false},
-	"runtime.environment": "development",
+	{"telemetry.openobserve.log.buffer.size", 2 * 1024, "Buffer size (in bytes) to wait before being sent to the server", false},
-
+	{"telemetry.openobserve.log.buffer.timeout", "2s", "Timeout to send logs if the buffer is not empty but not yet filled", false},
-	"scheduler.timeout": time.Second * 10,
+	{"telemetry.openobserve.log.username", "root@example.com", "OpenObserve logging endpoint username", false},
+	{"telemetry.openobserve.log.password", "Complexpass#123", "OpenObserve logging endpoint password", false},
+	{"telemetry.openobserve.trace.enable", true, "Wether to enable sending tracing to OpenObserve server", false},
+	{"telemetry.openobserve.trace.url", "http://localhost:5080/api/default/v1/traces", "Endpoint url to send traces to", false},
+	{"telemetry.openobserve.trace.auth", "Basic AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA", "Authorization token for the Endpoint URL", false},
+	{"telemetry.trace.ratio", float64(1), "Sampling ratio between 0 to 1 on how many traces are sent to the server. Value of 1 will send everything", false},
+
+	{"runtime.version", Version, "current server version", true},
+	{"runtime.environment", "development", "runtime environment", true},
+	{"flags.containerized", false, "Indicates the application is running in a container", true},
 }