feat(config): add config loading functions

src/server/config_load.go

@@ -0,0 +1,107 @@
+package server
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/ihexxa/gocfg"
+
+	"github.com/ihexxa/quickshare/src/db/sitestore"
+	"github.com/ihexxa/quickshare/src/kvstore/boltdbpvd"
+)
+
+type Opts struct {
+	Host    string   `short:"h" long:"host" description:"server hostname"`
+	Port    int      `short:"p" long:"port" description:"server port"`
+	DbPath  string   `short:"d" long:"db" description:"path of the quickshare.db"`
+	Configs []string `short:"c" long:"configs" description:"config path"`
+}
+
+func LoadCfg(opts *Opts) (*gocfg.Cfg, error) {
+	defaultCfg, err := DefaultConfig()
+	if err != nil {
+		return nil, err
+	}
+
+	cfg, err := gocfg.New(NewConfig()).Load(gocfg.JSONStr(defaultCfg))
+	if err != nil {
+		return nil, err
+	}
+
+	if opts.DbPath != "" {
+		cfg, err = mergeDbConfig(cfg, opts.DbPath)
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		_, err := os.Stat(boltdbpvd.DBName)
+		if err == nil {
+			cfg, err = mergeDbConfig(cfg, boltdbpvd.DBName)
+		} else if err != nil {
+			if !os.IsNotExist(err) {
+				return nil, err
+			}
+		}
+	}
+
+	cfg, err = mergeConfigFiles(cfg, opts.Configs)
+	if err != nil {
+		return nil, err
+	}
+
+	return mergeArgs(cfg, opts)
+}
+
+func mergeDbConfig(cfg *gocfg.Cfg, dbPath string) (*gocfg.Cfg, error) {
+	kv := boltdbpvd.New(dbPath, 1024)
+	defer kv.Close()
+
+	siteStore, err := sitestore.NewSiteStore(kv)
+	if err != nil {
+		return nil, fmt.Errorf("fail to new site config store: %s", err)
+	}
+
+	clientCfg, err := siteStore.GetCfg()
+	if err != nil {
+		return nil, err
+	}
+	clientCfgBytes, err := json.Marshal(clientCfg)
+	if err != nil {
+		return nil, err
+	}
+
+	cfgStr := fmt.Sprintf(`{"site": %s}`, string(clientCfgBytes))
+	return cfg.Load(gocfg.JSONStr(cfgStr))
+}
+
+func mergeConfigFiles(cfg *gocfg.Cfg, configPaths []string) (*gocfg.Cfg, error) {
+	var err error
+
+	for _, configPath := range configPaths {
+		if strings.HasSuffix(configPath, ".yml") || strings.HasSuffix(configPath, ".yaml") {
+			cfg, err = cfg.Load(gocfg.YAML(configPath))
+		} else if strings.HasSuffix(configPath, ".json") {
+			cfg, err = cfg.Load(gocfg.JSON(configPath))
+		} else {
+			return nil, fmt.Errorf("unknown config file type (.yml .yaml .json are supported): %s", configPath)
+		}
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return cfg, nil
+}
+
+func mergeArgs(cfg *gocfg.Cfg, opts *Opts) (*gocfg.Cfg, error) {
+	if opts.Host != "" {
+		cfg.SetString("Server.Host", opts.Host)
+	}
+	if opts.Port != 0 {
+		cfg.SetInt("Server.Port", opts.Port)
+	}
+
+	return cfg, nil
+}