feat: publish standalone worker

Separate worker packaging and service lifecycle from the control plane.

checks/cssl/cssl.go

@@ -0,0 +1,79 @@
+// Package cssl provides functionality.
+package cssl
+
+import (
+	"log"
+	"net/http"
+	"net/url"
+	"time"
+
+	"github.com/pkg/errors"
+
+	"rsgit.ru/rsmon/rsmon/app/models"
+)
+
+var client *http.Client
+
+func init() {
+	client = &http.Client{
+		Timeout: time.Second * 60,
+		CheckRedirect: func(_ *http.Request, _ []*http.Request) error {
+			return http.ErrUseLastResponse
+		},
+	}
+}
+
+// Perform provides functionality.
+func Perform(c *models.Check) *Result {
+	result := &Result{}
+	result.State = "OK"
+
+	var ur string
+	if c.URL != nil && *c.URL != "" {
+		ur = *c.URL
+
+		u, err := url.Parse(ur)
+		if err != nil {
+			result.State = "FAIL"
+			result.Error = errors.Wrap(err, "bad url")
+			return result
+		}
+		u.Scheme = "https"
+		ur = u.String()
+	} else {
+		ur = "https://" + c.Monitor.Host
+	}
+	log.Println("URL:", ur)
+	reqest, err := http.NewRequest("GET", ur, http.NoBody)
+	if err != nil {
+		result.State = "FAIL"
+		result.Error = err
+		return result
+	}
+
+	reqest.Header.Set("Cache-Control", "max-age=0")
+	reqest.Header.Set("Connection", "close")
+	resp, err := client.Do(reqest)
+	if err != nil {
+		result.State = "ERR"
+		result.Error = errors.Wrap(err, "https request error")
+		return result
+	}
+	defer resp.Body.Close() //nolint:errcheck
+
+	if resp.TLS == nil {
+		result.State = "ERR"
+		result.Error = errors.New("bad SSL cert CN")
+	} else {
+		cert := resp.TLS.VerifiedChains[0][0]
+		result.Expires = &cert.NotAfter
+		exp := time.Until(*result.Expires).Hours() / 24
+
+		if exp < 2 {
+			result.State = "WARN"
+			result.Warnings = append(result.Warnings, "Certificate expires soon")
+		}
+	}
+
+	return result
+}

checks/cssl/result.go

@@ -0,0 +1,10 @@
+package cssl
+
+import (
+	"rsgit.ru/rsmon/rsmon/internal/checkresult"
+)
+
+// Result is a result of a check
+type Result struct {
+	checkresult.CheckResult
+}