add an email service

2026-01-14 12:04:41 +00:00 · 2021-07-01 12:37:12 +01:00
parent 97298b9cfb
commit eb0165f4bf
11 changed files with 567 additions and 0 deletions
--- a/email/handler/email.go
+++ b/email/handler/email.go
@@ -0,0 +1,130 @@
+package handler
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+
+	"github.com/micro/micro/v3/service/config"
+	"github.com/micro/micro/v3/service/errors"
+	log "github.com/micro/micro/v3/service/logger"
+	pb "github.com/micro/services/email/proto"
+)
+
+type sendgridConf struct {
+	Key  string `json:"key"`
+	EmailFrom string `json:"email_from"`
+}
+
+func NewEmailHandler() *Email {
+	c := sendgridConf{}
+	val, err := config.Get("sendgridapi")
+	if err != nil {
+		log.Warnf("Error getting config: %v", err)
+	}
+	err = val.Scan(&c)
+	if err != nil {
+		log.Warnf("Error scanning config: %v", err)
+	}
+	if len(c.Key) == 0 {
+		log.Fatalf("Sendgrid API key not configured")
+	}
+	return &Email{
+		c,
+	}
+}
+
+type Email struct {
+	config sendgridConf
+}
+
+func (e *Email) Send(ctx context.Context, request *pb.SendRequest, response *pb.SendResponse) error {
+	if len(request.From) == 0 {
+		return errors.BadRequest("email.send.validation", "Missing from address")
+	}
+	if len(request.To) == 0 {
+		return errors.BadRequest("email.send.validation", "Missing to address")
+	}
+	if len(request.Subject) == 0 {
+		return errors.BadRequest("email.send.validation", "Missing subject")
+	}
+	if len(request.TextBody) == 0 && len(request.HtmlBody) == 0 {
+		return errors.BadRequest("email.send.validation", "Missing email body")
+	}
+
+	if err := e.sendEmail(request); err != nil {
+		log.Errorf("Error sending email: %v\n", err)
+		return errors.InternalServerError("email.sendemail", "Error sending email")
+	}
+
+	return nil
+}
+
+// sendEmail sends an email invite via the sendgrid API using the
+// pre-designed email template. Docs: https://bit.ly/2VYPQD1
+func (e *Email) sendEmail(req *pb.SendRequest) error {
+	content := []interface{}{}
+
+	if len(req.TextBody) > 0 {
+		content = append(content, map[string]string{
+			"type":  "text/plain",
+			"value": req.TextBody,
+		})
+	}
+
+	if len(req.HtmlBody) > 0 {
+		content = append(content, map[string]string{
+			"type":  "text/html",
+			"value": req.HtmlBody,
+		})
+	}
+
+	reqBody, _ := json.Marshal(map[string]interface{}{
+		"from": map[string]string{
+			"email": e.config.EmailFrom,
+			"name":  req.From,
+		},
+		"reply_to": map[string]string{
+			"email": e.config.EmailFrom,
+			"name":  req.From,
+		},
+		"subject": req.Subject,
+		"content": content,
+		"personalizations": []interface{}{
+			map[string]interface{}{
+				"to": []map[string]string{
+					{
+						"email": req.To,
+					},
+				},
+			},
+		},
+	})
+
+	httpReq, err := http.NewRequest("POST", "https://api.sendgrid.com/v3/mail/send", bytes.NewBuffer(reqBody))
+	if err != nil {
+		return err
+	}
+
+	httpReq.Header.Set("Authorization", "Bearer "+e.config.Key)
+	httpReq.Header.Set("Content-Type", "application/json")
+
+	rsp, err := new(http.Client).Do(httpReq)
+	if err != nil {
+		return fmt.Errorf("could not send email, error: %v", err)
+	}
+	defer rsp.Body.Close()
+
+	if rsp.StatusCode < 200 || rsp.StatusCode > 299 {
+		bytes, err := ioutil.ReadAll(rsp.Body)
+		if err != nil {
+			return err
+		}
+		return fmt.Errorf("could not send email, error: %v", string(bytes))
+	}
+
+	return nil
+}