Improve implementation around config (#1122)

* refactor config

* fix saas config

* feat(config): scanmodule for each server in config.toml

* feat(config): enable to specify containersOnly in config.toml

* add new keys of config.toml to discover.go

* fix summary output, logging

config/govaldictconf.go

@@ -0,0 +1,54 @@
+package config
+
+import (
+	"os"
+	"path/filepath"
+)
+
+// GovalDictConf is goval-dictionary config
+type GovalDictConf struct {
+
+	// DB type of OVAL dictionary (sqlite3, mysql, postgres or redis)
+	Type string
+
+	// http://goval-dictionary.com:1324 or DB connection string
+	URL string `json:"-"`
+
+	// /path/to/oval.sqlite3
+	SQLite3Path string `json:"-"`
+}
+
+func (cnf *GovalDictConf) setDefault() {
+	if cnf.Type == "" {
+		cnf.Type = "sqlite3"
+	}
+	if cnf.URL == "" && cnf.SQLite3Path == "" {
+		wd, _ := os.Getwd()
+		cnf.SQLite3Path = filepath.Join(wd, "oval.sqlite3")
+	}
+}
+
+const govalType = "OVALDB_TYPE"
+const govalURL = "OVALDB_URL"
+const govalPATH = "OVALDB_SQLITE3_PATH"
+
+// Init set options with the following priority.
+// 1. Environment variable
+// 2. config.toml
+func (cnf *GovalDictConf) Init() {
+	if os.Getenv(govalType) != "" {
+		cnf.Type = os.Getenv(govalType)
+	}
+	if os.Getenv(govalURL) != "" {
+		cnf.URL = os.Getenv(govalURL)
+	}
+	if os.Getenv(govalPATH) != "" {
+		cnf.SQLite3Path = os.Getenv(govalPATH)
+	}
+	cnf.setDefault()
+}
+
+// IsFetchViaHTTP returns wether fetch via http
+func (cnf *GovalDictConf) IsFetchViaHTTP() bool {
+	return Conf.OvalDict.Type == "http"
+}