Initialize mailer client in constructor

Author: lfir

src/main/java/cf/maybelambda/httpvalidator/springboot/service/EmailNotificationService.java

@@ -8,6 +8,7 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Value;
 import org.springframework.core.env.Environment;
 import org.springframework.lang.NonNull;
 import org.springframework.stereotype.Service;
@@ -18,7 +19,6 @@
 import static cf.maybelambda.httpvalidator.springboot.util.HttpSendOutcomeWrapper.NET_ERR_CODE;
 import static io.micrometer.common.util.StringUtils.isBlank;
 import static io.micrometer.common.util.StringUtils.truncate;
-import static java.util.Objects.isNull;
 
 /**
  * Service to send email notifications using external SMTP service.
@@ -37,6 +37,10 @@ public class EmailNotificationService {
     @Autowired
     private Environment env;
 
+    public EmailNotificationService(@Value("${" + APIKEY_PROPERTY + "}") String apiKey) {
+        this.client = MailgunClient.config(apiKey).createApi(MailgunMessagesApi.class);
+    }
+
     /**
      * Builds the email body content from a list of validation results.
      *
@@ -70,8 +74,6 @@ String buildMailBody(List<String[]> contents) {
     void sendPlainTextEmail(String subject, String body) throws ConnectIOException {
         if (!this.isValidConfig()) return;
 
-        if (isNull(this.client)) this.client = MailgunClient.config(this.getApiKey()).createApi(MailgunMessagesApi.class);
-
         Message message = Message.builder()
             .from(this.getFrom())
             .to(this.getTo())

src/test/java/cf/maybelambda/httpvalidator/springboot/service/EmailNotificationServiceTests.java

@@ -39,7 +39,7 @@ public class EmailNotificationServiceTests {
 
     @BeforeEach
     void setUp() {
-        this.mailServ = new EmailNotificationService();
+        this.mailServ = new EmailNotificationService("apiKey");
         this.mailServ.setClient(this.cl);
         this.mailServ.setEnv(this.env);
     }
@@ -171,7 +171,7 @@ void emailNotificationServiceInstanceUsesNewMailerClientToSendEmailWhenNoneWasSe
         given(this.env.getProperty(APIKEY_PROPERTY)).willReturn("apiKey");
         given(this.env.getProperty(FROM_PROPERTY)).willReturn("[email protected]");
         given(this.env.getProperty(TO_PROPERTY)).willReturn("[email protected]");
-        EmailNotificationService serv = new EmailNotificationService();
+        EmailNotificationService serv = new EmailNotificationService("apiKey");
         serv.setEnv(this.env);
         serv.setLogger(this.logger);