simplified config by using envconfig package

go.mod

@@ -6,6 +6,7 @@ toolchain go1.24.3
 
 require (
 	github.com/joho/godotenv v1.5.1
+	github.com/kelseyhightower/envconfig v1.4.0
 	github.com/nbd-wtf/go-nostr v0.51.12
 	github.com/pippellia-btc/nastro v0.3.0
 	github.com/pippellia-btc/slicex v0.2.4

go.sum

@@ -37,6 +37,8 @@ github.com/josharian/intern v1.0.0 h1:vlS4z54oSdjm0bgjRigI+G1HpF+tI+9rE5LLzOg8Hm
 github.com/josharian/intern v1.0.0/go.mod h1:5DoeVV0s6jJacbCEi61lwdGj/aVlrQvzHFFd8Hwg//Y=
 github.com/json-iterator/go v1.1.12 h1:PV8peI4a0ysnczrg+LtxykD8LfKY9ML6u2jnxaEnrnM=
 github.com/json-iterator/go v1.1.12/go.mod h1:e30LSqwooZae/UwlEbR2852Gd8hjQvJoHmT4TnhNGBo=
+github.com/kelseyhightower/envconfig v1.4.0 h1:Im6hONhd3pLkfDFsbRgu68RDNkGF1r3dvMUtDTo2cv8=
+github.com/kelseyhightower/envconfig v1.4.0/go.mod h1:cccZRl6mQpaq41TPp5QxidR+Sa3axMbJDNb//FQX6Gg=
 github.com/klauspost/cpuid/v2 v2.0.9/go.mod h1:FInQzS24/EEf25PyTYn52gqo7WaD8xa0213Md/qVLRg=
 github.com/klauspost/cpuid/v2 v2.2.10 h1:tBs3QSyvjDyFTq3uoc/9xFpCuOsJQFNPiAhYdw2skhE=
 github.com/klauspost/cpuid/v2 v2.2.10/go.mod h1:hqwkgyIinND0mEev00jJYCxPNVRVXFQeu1XKlok6oO0=

pkg/config/config.go

@@ -2,12 +2,10 @@
 package config
 
 import (
+	"errors"
 	"fmt"
-	"os"
-	"strconv"
-	"strings"
-	"time"
 
+	"github.com/kelseyhightower/envconfig"
 	"github.com/vertex-lab/crawler_v2/pkg/pipe"
 
 	_ "github.com/joho/godotenv/autoload" // autoloading .env
@@ -15,14 +13,12 @@ import (
 )
 
 type SystemConfig struct {
-	RedisAddress string
-	SQLiteURL    string
-
-	EventsCapacity  int
-	PubkeysCapacity int
-
-	InitPubkeys []string // only used during initialization
-	PrintStats  bool
+	RedisAddress    string   `envconfig:"REDIS_ADDRESS"`
+	SQLiteURL       string   `envconfig:"SQLITE_URL"`
+	EventsCapacity  int      `envconfig:"EVENTS_CAPACITY"`
+	PubkeysCapacity int      `envconfig:"PUBKEYS_CAPACITY"`
+	InitPubkeys     []string `envconfig:"INIT_PUBKEYS"`
+	PrintStats      bool     `envconfig:"PRINT_STATS"`
 }
 
 func NewSystemConfig() SystemConfig {
@@ -34,6 +30,19 @@ func NewSystemConfig() SystemConfig {
 	}
 }
 
+func (c SystemConfig) Validate() error {
+	if c.EventsCapacity < 0 {
+		return errors.New("events: value cannot be negative")
+	}
+
+	for _, pk := range c.InitPubkeys {
+		if !nostr.IsValidPublicKey(pk) {
+			return fmt.Errorf("init pubkeys: \"%s\" is not valid hex pubkey", pk)
+		}
+	}
+	return nil
+}
+
 func (c SystemConfig) Print() {
 	fmt.Println("System:")
 	fmt.Printf("  RedisAddress: %s\n", c.RedisAddress)
@@ -54,8 +63,8 @@ type Config struct {
 }
 
 // New returns a config with default parameters
-func New() *Config {
-	return &Config{
+func New() Config {
+	return Config{
 		SystemConfig: NewSystemConfig(),
 		Firehose:     pipe.NewFirehoseConfig(),
 		Fetcher:      pipe.NewFetcherConfig(),
@@ -64,7 +73,30 @@ func New() *Config {
 	}
 }
 
-func (c *Config) Print() {
+func (c Config) Validate() error {
+	if err := c.SystemConfig.Validate(); err != nil {
+		return fmt.Errorf("System: %w", err)
+	}
+
+	if err := c.Firehose.Validate(); err != nil {
+		return fmt.Errorf("Firehose: %w", err)
+	}
+
+	if err := c.Fetcher.Validate(); err != nil {
+		return fmt.Errorf("Fetcher: %w", err)
+	}
+
+	if err := c.Arbiter.Validate(); err != nil {
+		return fmt.Errorf("Arbiter: %w", err)
+	}
+
+	if err := c.Engine.Validate(); err != nil {
+		return fmt.Errorf("Engine: %w", err)
+	}
+	return nil
+}
+
+func (c Config) Print() {
 	c.SystemConfig.Print()
 	c.Firehose.Print()
 	c.Fetcher.Print()
@@ -72,138 +104,17 @@ func (c *Config) Print() {
 	c.Engine.Print()
 }
 
-// Load reads the enviroment variables and parses them into a [Config] struct
-func Load() (*Config, error) {
-	var config = New()
-	var err error
+// Load creates a new [Config] with default parameters.
+// Then, if the corresponding environment variable is set, it overwrites them.
+func Load() (Config, error) {
+	config := New()
 
-	for _, item := range os.Environ() {
-		keyVal := strings.SplitN(item, "=", 2)
-		key, val := keyVal[0], keyVal[1]
-
-		switch key {
-		case "REDIS_ADDRESS":
-			config.RedisAddress = val
-
-		case "SQLITE_URL":
-			config.SQLiteURL = val
-
-		case "EVENTS_CAPACITY":
-			config.EventsCapacity, err = strconv.Atoi(val)
-			if err != nil {
-				return nil, fmt.Errorf("error parsing %v: %v", keyVal, err)
+	if err := envconfig.Process("", &config); err != nil {
+		return Config{}, fmt.Errorf("config.Load: %w", err)
 	}
 
-		case "PUBKEYS_CAPACITY":
-			config.PubkeysCapacity, err = strconv.Atoi(val)
-			if err != nil {
-				return nil, fmt.Errorf("error parsing %v: %v", keyVal, err)
-			}
-
-		case "INIT_PUBKEYS":
-			pubkeys := strings.Split(val, ",")
-			for _, pk := range pubkeys {
-				if !nostr.IsValidPublicKey(pk) {
-					return nil, fmt.Errorf("pubkey %s is not valid", pk)
-				}
-			}
-
-			config.InitPubkeys = pubkeys
-
-		case "PRINT_STATS":
-			config.PrintStats, err = strconv.ParseBool(val)
-			if err != nil {
-				return nil, fmt.Errorf("error parsing %v: %v", keyVal, err)
-			}
-
-		case "FIREHOSE_OFFSET":
-			offset, err := strconv.Atoi(val)
-			if err != nil {
-				return nil, fmt.Errorf("error parsing %v: %v", keyVal, err)
-			}
-			config.Fetcher.Interval = time.Duration(offset) * time.Second
-
-		case "RELAYS":
-			relays := strings.Split(val, ",")
-			if len(relays) == 0 {
-				return nil, fmt.Errorf("relay list is empty")
-			}
-
-			for _, relay := range relays {
-				if !nostr.IsValidRelayURL(relay) {
-					return nil, fmt.Errorf("relay \"%s\" is not a valid url", relay)
-				}
-			}
-
-			config.Firehose.Relays = relays
-			config.Fetcher.Relays = relays
-
-		case "FETCHER_BATCH":
-			config.Fetcher.Batch, err = strconv.Atoi(val)
-			if err != nil {
-				return nil, fmt.Errorf("error parsing %v: %v", keyVal, err)
-			}
-
-		case "FETCHER_INTERVAL":
-			interval, err := strconv.Atoi(val)
-			if err != nil {
-				return nil, fmt.Errorf("error parsing %v: %v", keyVal, err)
-			}
-			config.Fetcher.Interval = time.Duration(interval) * time.Second
-
-		case "ARBITER_ACTIVATION":
-			config.Arbiter.Activation, err = strconv.ParseFloat(val, 64)
-			if err != nil {
-				return nil, fmt.Errorf("error parsing %v: %v", keyVal, err)
-			}
-
-		case "ARBITER_PROMOTION":
-			config.Arbiter.Promotion, err = strconv.ParseFloat(val, 64)
-			if err != nil {
-				return nil, fmt.Errorf("error parsing %v: %v", keyVal, err)
-			}
-
-		case "ARBITER_DEMOTION":
-			config.Arbiter.Demotion, err = strconv.ParseFloat(val, 64)
-			if err != nil {
-				return nil, fmt.Errorf("error parsing %v: %v", keyVal, err)
-			}
-
-		case "ARBITER_PING_WAIT":
-			wait, err := strconv.ParseInt(val, 10, 64)
-			if err != nil {
-				return nil, fmt.Errorf("error parsing %v: %v", keyVal, err)
-			}
-			config.Arbiter.PingWait = time.Duration(wait) * time.Second
-
-		case "ARBITER_PROMOTION_WAIT":
-			wait, err := strconv.ParseInt(val, 10, 64)
-			if err != nil {
-				return nil, fmt.Errorf("error parsing %v: %v", keyVal, err)
-			}
-			config.Arbiter.PromotionWait = time.Duration(wait) * time.Second
-
-		case "ENGINE_PRINT_EVERY":
-			printEvery, err := strconv.Atoi(val)
-			if err != nil {
-				return nil, fmt.Errorf("error parsing %v: %v", keyVal, err)
-			}
-
-			config.Engine.Archiver.PrintEvery = printEvery
-			config.Engine.Builder.PrintEvery = printEvery
-
-		case "ENGINE_BUILDER_CAPACITY":
-			config.Engine.ChannelCapacity, err = strconv.Atoi(val)
-			if err != nil {
-				return nil, fmt.Errorf("error parsing %v: %v", keyVal, err)
-			}
-
-		case "ENGINE_CACHE_CAPACITY":
-			config.Engine.Builder.CacheCapacity, err = strconv.Atoi(val)
-			if err != nil {
-				return nil, fmt.Errorf("error parsing %v: %v", keyVal, err)
-			}
-		}
+	if err := config.Validate(); err != nil {
+		return Config{}, fmt.Errorf("config.Load: %w", err)
 	}
 
 	return config, nil

pkg/pipe/arbiter.go

@@ -2,6 +2,7 @@ package pipe
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"log"
 	"sync/atomic"
@@ -18,12 +19,11 @@ import (
 var WalksTracker atomic.Int32
 
 type ArbiterConfig struct {
-	Activation float64
-	Promotion  float64
-	Demotion   float64
-
-	PromotionWait time.Duration
-	PingWait      time.Duration
+	Activation    float64       `envconfig:"ARBITER_ACTIVATION"`
+	Promotion     float64       `envconfig:"ARBITER_PROMOTION"`
+	Demotion      float64       `envconfig:"ARBITER_DEMOTION"`
+	PromotionWait time.Duration `envconfig:"ARBITER_PROMOTION_WAIT"`
+	PingWait      time.Duration `envconfig:"ARBITER_PING_WAIT"`
 }
 
 func NewArbiterConfig() ArbiterConfig {
@@ -36,8 +36,38 @@ func NewArbiterConfig() ArbiterConfig {
 	}
 }
 
+func (c ArbiterConfig) Validate() error {
+	if c.Activation < 0 {
+		return errors.New("activation ratio cannot be negative")
+	}
+
+	if c.Promotion < 0 {
+		return errors.New("promotion multiplier cannot be negative")
+	}
+
+	if c.Demotion < 0 {
+		return errors.New("demotion multiplier cannot be negative")
+	}
+
+	if c.Demotion <= 1 {
+		log.Println("WARN: Arbiter: demotion multiplier is smaller than 1." +
+			"This implies it's impossible for an active node to be demoted")
+	}
+
+	if 1+c.Promotion <= c.Demotion {
+		log.Println("WARN: Arbiter: the inequality (1 + promotion) > demotion is not satisfied." +
+			"This implies there will be cyclical promotions -> demotions -> promotions...")
+	}
+
+	if c.PromotionWait < 24*time.Hour {
+		log.Println("WARN: Arbiter: the promotion wait is less than 24hrs." +
+			"This implies a reputable attacker could add to the db several bots in a short period of time")
+	}
+	return nil
+}
+
 func (c ArbiterConfig) Print() {
-	fmt.Printf("Arbiter\n")
+	fmt.Printf("Arbiter: \n")
 	fmt.Printf("  Activation: %f\n", c.Activation)
 	fmt.Printf("  Promotion: %f\n", c.Promotion)
 	fmt.Printf("  Demotion: %f\n", c.Demotion)

pkg/pipe/engine.go

@@ -3,6 +3,7 @@ package pipe
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"log"
 	"slices"
@@ -20,7 +21,7 @@ import (
 type EngineConfig struct {
 	Archiver        ArchiverConfig
 	Builder         GraphBuilderConfig
-	ChannelCapacity int
+	ChannelCapacity int `envconfig:"ENGINE_BUILDER_CAPACITY"`
 }
 
 func NewEngineConfig() EngineConfig {
@@ -30,8 +31,20 @@ func NewEngineConfig() EngineConfig {
 	}
 }
 
+func (c EngineConfig) Validate() error {
+	if err := c.Archiver.Validate(); err != nil {
+		return fmt.Errorf("Archiver: %w", err)
+	}
+
+	if err := c.Builder.Validate(); err != nil {
+		return fmt.Errorf("GraphBuilder: %w", err)
+	}
+
+	return nil
+}
+
 func (c EngineConfig) Print() {
-	fmt.Printf("Engine\n")
+	fmt.Printf("Engine:\n")
 	fmt.Printf("  ChannelCapacity: %d\n", c.ChannelCapacity)
 	c.Archiver.Print()
 	c.Builder.Print()
@@ -60,8 +73,8 @@ func Engine(
 }
 
 type ArchiverConfig struct {
-	Kinds      []int
-	PrintEvery int
+	Kinds      []int `envconfig:"ARCHIVER_KINDS"`
+	PrintEvery int   `envconfig:"ENGINE_PRINT_EVERY"`
 }
 
 func NewArchiverConfig() ArchiverConfig {
@@ -71,8 +84,19 @@ func NewArchiverConfig() ArchiverConfig {
 	}
 }
 
+func (c ArchiverConfig) Validate() error {
+	if len(c.Kinds) < 1 {
+		return errors.New("kind list cannot be empty")
+	}
+
+	if c.PrintEvery < 0 {
+		return errors.New("print every cannot be negative")
+	}
+	return nil
+}
+
 func (c ArchiverConfig) Print() {
-	fmt.Printf("Archiver\n")
+	fmt.Printf("Archiver:\n")
 	fmt.Printf("  Kinds: %v\n", c.Kinds)
 	fmt.Printf("  PrintEvery: %d\n", c.PrintEvery)
 }
@@ -149,8 +173,8 @@ func archive(
 }
 
 type GraphBuilderConfig struct {
-	CacheCapacity int
-	PrintEvery    int
+	CacheCapacity int `envconfig:"ENGINE_CACHE_CAPACITY"`
+	PrintEvery    int `envconfig:"ENGINE_PRINT_EVERY"`
 }
 
 func NewGraphBuilderConfig() GraphBuilderConfig {
@@ -160,8 +184,19 @@ func NewGraphBuilderConfig() GraphBuilderConfig {
 	}
 }
 
+func (c GraphBuilderConfig) Validate() error {
+	if c.CacheCapacity < 0 {
+		return errors.New("cache capacity cannot be negative")
+	}
+
+	if c.PrintEvery < 0 {
+		return errors.New("print every cannot be negative")
+	}
+	return nil
+}
+
 func (c GraphBuilderConfig) Print() {
-	fmt.Printf("GraphBuilder\n")
+	fmt.Printf("GraphBuilder:\n")
 	fmt.Printf("  CacheCapacity: %v\n", c.CacheCapacity)
 	fmt.Printf("  PrintEvery: %d\n", c.PrintEvery)
 }

pkg/pipe/fetcher.go

@@ -2,6 +2,7 @@ package pipe
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"log"
 	"time"
@@ -11,10 +12,10 @@ import (
 )
 
 type FetcherConfig struct {
-	Kinds    []int
-	Relays   []string
-	Batch    int
-	Interval time.Duration
+	Kinds    []int         `envconfig:"FETCHER_KINDS"`
+	Relays   []string      `envconfig:"RELAYS"`
+	Batch    int           `envconfig:"FETCHER_BATCH"`
+	Interval time.Duration `envconfig:"FETCHER_INTERVAL"`
 }
 
 func NewFetcherConfig() FetcherConfig {
@@ -26,8 +27,25 @@ func NewFetcherConfig() FetcherConfig {
 	}
 }
 
+func (c FetcherConfig) Validate() error {
+	if len(c.Kinds) < 1 {
+		return errors.New("kind list cannot be empty")
+	}
+
+	if c.Batch <= 1 {
+		return errors.New("batch value must be positive")
+	}
+
+	for _, relay := range c.Relays {
+		if !nostr.IsValidRelayURL(relay) {
+			return fmt.Errorf("\"%s\" is not a valid relay url", relay)
+		}
+	}
+	return nil
+}
+
 func (c FetcherConfig) Print() {
-	fmt.Printf("Fetcher\n")
+	fmt.Printf("Fetcher:\n")
 	fmt.Printf("  Kinds: %v\n", c.Kinds)
 	fmt.Printf("  Relays: %v\n", c.Relays)
 	fmt.Printf("  Batch: %d\n", c.Batch)

pkg/pipe/firehose.go

@@ -2,6 +2,7 @@ package pipe
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"log"
 	"slices"
@@ -76,9 +77,9 @@ var (
 )
 
 type FirehoseConfig struct {
-	Kinds  []int
-	Relays []string
-	Offset time.Duration
+	Kinds  []int         `envconfig:"FIREHOSE_KINDS"`
+	Relays []string      `envconfig:"RELAYS"`
+	Offset time.Duration `envconfig:"FIREHOSE_OFFSET"`
 }
 
 func NewFirehoseConfig() FirehoseConfig {
@@ -89,13 +90,26 @@ func NewFirehoseConfig() FirehoseConfig {
 	}
 }
 
+func (c FirehoseConfig) Validate() error {
+	if len(c.Kinds) < 1 {
+		return errors.New("kind list cannot be empty")
+	}
+
+	for _, relay := range c.Relays {
+		if !nostr.IsValidRelayURL(relay) {
+			return fmt.Errorf("\"%s\" is not a valid relay url", relay)
+		}
+	}
+	return nil
+}
+
 func (c FirehoseConfig) Since() *nostr.Timestamp {
 	since := nostr.Timestamp(time.Now().Add(-c.Offset).Unix())
 	return &since
 }
 
 func (c FirehoseConfig) Print() {
-	fmt.Printf("Firehose\n")
+	fmt.Printf("Firehose:\n")
 	fmt.Printf("  Kinds: %v\n", c.Kinds)
 	fmt.Printf("  Relays: %v\n", c.Relays)
 	fmt.Printf("  Offset: %v\n", c.Offset)