Release 0.2.0

- new language: go
- new shops: cybertek.fr, mediamarkt.ch
- deprecated shops: alternate.be, minershop.eu
- improved database transaction management
- better web parsing library (ferret, requires headless chrome browser)
- include or exclude products by applying regex on their names
- check for PID file to avoid running the bot twice
- hastags are now configurable

Signed-off-by: Julien Riou <julien@riou.xyz>

utils.go

@@ -0,0 +1,29 @@
+package main
+
+import (
+	"net/url"
+	"regexp"
+	"strings"
+)
+
+// ExtractShopName parses a link to extract the hostname, then remove leading www, to build the Shop name
+// "https://www.ldlc.com/informatique/pieces-informatique/[...]" -> "ldlc.com"
+func ExtractShopName(link string) (name string, err error) {
+	u, err := url.Parse(link)
+	if err != nil {
+		return "", err
+	}
+	re := regexp.MustCompile(`^www\.`)
+	return strings.ToLower(re.ReplaceAllString(u.Hostname(), "")), nil
+}
+
+// compileRegex transforms a regex from string to regexp instance
+func compileRegex(pattern string) (regex *regexp.Regexp, err error) {
+	if pattern != "" {
+		regex, err = regexp.Compile(pattern)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return regex, nil
+}