feat(config): create config package for parsing environment

1 files changed, 102 insertions, 0 deletions

diff --git a/src/config/config.go b/src/config/config.go
new file mode 100644
index 0000000..3f3603a
--- /dev/null
+++ b/src/config/config.go
@@ -0,0 +1,102 @@
+package config
+
+import (
+	"errors"
+	"fmt"
+	"log/slog"
+	"os"
+	"strings"
+)
+
+const (
+	CardmarketAppToken          = "CM_APP_TOKEN"
+	CardmarketAppSecret         = "CM_APP_SECRET"
+	CardmarketAccessToken       = "CM_ACCESS_TOKEN"
+	CardmarketAccessTokenSecret = "CM_ACCESS_TOKEN_SECRET"
+	CardmarketApiBaseURL        = "CM_API_BASE_URL"
+	AppLogLevel                 = "APP_LOG_LEVEL"
+)
+
+var (
+	ErrMissingCardmarketAppToken          = errors.New("err: missing " + CardmarketAppToken + " in ENV")
+	ErrMissingCardmarketAppSecret         = errors.New("err: missing " + CardmarketAppSecret + " in ENV")
+	ErrMissingCardmarketAccessToken       = errors.New("err: missing " + CardmarketAccessToken + " in ENV")
+	ErrMissingCardmarketAccessTokenSecret = errors.New("err: missing " + CardmarketAccessTokenSecret + " in ENV")
+	ErrMissingCardmarketApiBaseURL        = errors.New("err: missing " + CardmarketApiBaseURL + " in ENV")
+)
+
+type CardmarketApiAuth struct {
+	AppToken          []byte
+	AppSecret         []byte
+	AccessToken       []byte
+	AccessTokenSecret []byte
+}
+
+func (auth *CardmarketApiAuth) String() string {
+	return fmt.Sprintf(
+		"CardmarketApiAuth{AppToken: %s, AppSecret: %s, AccessToken: %s, AccessTokenSecret: %s}",
+		string(auth.AppToken[:3])+strings.Repeat("*", 5),
+		string(auth.AppSecret[:3])+strings.Repeat("*", 5),
+		string(auth.AccessToken[:3])+strings.Repeat("*", 5),
+		string(auth.AccessTokenSecret[:3])+strings.Repeat("*", 5),
+	)
+}
+
+type Config struct {
+	CardmarketApiBaseURL []byte
+	CardmarketApiAuth    CardmarketApiAuth
+	AppLogLevel          slog.Level
+}
+
+func NewConfigFromEnv() (Config, error) {
+	appToken := os.Getenv(CardmarketAppToken)
+	if appToken == "" {
+		return Config{}, ErrMissingCardmarketAppToken
+	}
+
+	appSecret := os.Getenv(CardmarketAppSecret)
+	if appSecret == "" {
+		return Config{}, ErrMissingCardmarketAppSecret
+	}
+
+	accessToken := os.Getenv(CardmarketAccessToken)
+	if accessToken == "" {
+		return Config{}, ErrMissingCardmarketAccessToken
+	}
+
+	accessTokenSecret := os.Getenv(CardmarketAccessTokenSecret)
+	if accessTokenSecret == "" {
+		return Config{}, ErrMissingCardmarketAccessTokenSecret
+	}
+
+	apiBaseURL := os.Getenv(CardmarketApiBaseURL)
+	if apiBaseURL == "" {
+		return Config{}, ErrMissingCardmarketApiBaseURL
+	}
+
+	lvl := slog.LevelDebug
+	appLogLevel := os.Getenv(AppLogLevel)
+	if lvlErr := lvl.UnmarshalText([]byte(appLogLevel)); lvlErr != nil {
+		return Config{}, errors.Join(errors.New("could not unmarshal "+AppLogLevel), lvlErr)
+	}
+
+	return Config{
+		CardmarketApiBaseURL: []byte(apiBaseURL),
+		CardmarketApiAuth: CardmarketApiAuth{
+			AppToken:          []byte(appToken),
+			AppSecret:         []byte(appSecret),
+			AccessToken:       []byte(accessToken),
+			AccessTokenSecret: []byte(accessTokenSecret),
+		},
+		AppLogLevel: lvl,
+	}, nil
+}
+
+func (conf *Config) String() string {
+	return fmt.Sprintf(
+		"Config{CardmarketApiBaseURL: %s, CardmarketApiAuth: %s, AppLogLevel: %s}",
+		conf.CardmarketApiBaseURL,
+		conf.CardmarketApiAuth.String(),
+		conf.AppLogLevel,
+	)
+}