This post will provide a complete walkthrough for integrating an email API focused specifically on sending emails. It will cover the setup, implementation across different programming languages, and best practices to ensure reliable delivery and smooth integration. You’ll find:
Whether you are setting up simple email alerts or sending many automated messages, this post will guide you. It covers every step, from setup to sending. This way, your application can send emails easily and effectively.
In today’s digital world, sending emails programmatically has become essential for applications handling user notifications, transactional messages, and automated communication.
Using an Email API is the easiest way to send emails from your app. You won’t have to deal with complex email servers or manual setup.
An email API offers a simple way to connect your app to email services like Gmail and Outlook. With just a few API calls, developers can send personalized emails for users without opening an inbox. This method works well for apps that need to send automated emails, like account alerts and marketing messages.
Leveraging an email API to send emails provides significant advantages for developers and users alike:
Using an email API to send emails can greatly benefit both developers and users. This makes it a popular choice for many applications.
Using an email API to send emails improves communication. It makes the process reliable, scalable, and suited to user needs. In the next sections, we will look at how to set up and use an email API. We will cover different programming environments and scenarios. This will help you add these benefits directly to your application.
To set up an email API for sending emails, follow a few key steps. This will help ensure smooth integration and secure operation.
Begin by choosing an email API provider that matches your application’s needs. Consider the following factors:
For this blog post, we’ll be using Nylas as the email API product. Nylas is a popular choice for sending and managing emails because it offers:
After selecting a provider, create an account and obtain the necessary API credentials, typically including:
For security, store these credentials in environment variables rather than hardcoding them into your application. This minimizes the risk of exposing sensitive information in code repositories.
Let’s do that with Nylas. To start:
Store credentials securely: Save these credentials in environment variables. For example, in a .env file:
NYLAS_API_KEY=your_api_key NYLAS_API_URI=your_api_uri NYLAS_GRANT_ID=your_grant_id
Before you start coding, prepare your environment for a smooth integration:
Now we’ll prepare our development environment to start using the Nylas API:
Node.js
Ruby
Python
Java
npm install nylas
gem install nylas
pip install nylas
//for Java/Kotlin, use inside your pom.xml
<groupId>com.nylas.sdk</groupId>
<artifactId>nylas</artifactId>
<version>2.5.1</version>
Suppose you’re using a language without a dedicated SDK (such as PHP, Rust or C#). You can use common HTTP request libraries like axios for JavaScript, reqwest for Rust, or RestSharp for C#.
2. Set Up Environment Variables: Keep your API credentials in environment variables. This helps manage them securely in development, staging, and production.
3. Enable necessary permissions: In your Nylas application settings, ensure you’ve enabled the required permissions for sending emails. Nylas allows you to specify access levels based on your application’s needs.
With the API credentials set up, you’re ready to send a test email:
Now that we have the environment is set up, we’re ready to send an email through Nylas:
Curl
curl -X POST "https://api.us.nylas.com/v3/grants/NYLAS_GRANT_ID/messages/send" \
-H "accept: application/json"\
-H "content-type: application/json" \
-H "authorization: Bearer NYLAS_API_KEY"\
-d '{"subject":"Hello",
"body":"Hello from Nylas",
"to":[{"name":"Swag","email":"[email protected]"}]
}'
2. Execute the API Call: Run this on your terminal window.
3. Handle Responses: Monitor the response from Nylas. A successful response indicates the email was sent, while an error response will provide details if something went wrong. Logging these responses is helpful for troubleshooting and verifying that emails are being delivered as expected.
By completing these steps, you’ll have a working setup to send emails through an API. In the next sections, we will give examples of sending emails. We will use different SDKs and languages. This will help you create a reliable and efficient email-sending feature for your application.
Integrating an email API to send emails is straightforward, especially when using SDKs that handle much of the setup and configuration. Here, we explain how to send emails with Nylas. We will use different SDKs and programming languages, like Ruby, Python, and Node. We will also mention options for other languages.
Node.js
Ruby
Python
Java
npm install nylas
npm install dotenv
gem install nylas
gem install dotenv
pip install nylas
pip install python-dotenv
<dependency>
<groupId>com.nylas.sdk</groupId>
<artifactId>nylas</artifactId>
<version>2.5.1</version>
</dependency>
<dependency>
<groupId>io.github.cdimascio</groupId>
<artifactId>dotenv-kotlin</artifactId>
<version>6.4.2</version>
</dependency>
Node.js
Ruby
Python
Java
import 'dotenv/config'
import Nylas from 'nylas'
import * as readline from "readline";
const NylasConfig = {
apiKey: process.env.NYLAS_API_KEY,
apiUri: process.env.NYLAS_API_URI,
}
const rl = readline.createInterface({
input: process.stdin,
output: process.stdout
});
const askQuestion = (question) => {
return new Promise((resolve) => {
rl.question(question, (answer) => {
resolve(answer);
});
});
};
const nylas = new Nylas(NylasConfig)
const main = async () => {
const subject = await askQuestion('Enter a subject: ');
const body = await askQuestion('Enter the body: ');
const name = await askQuestion('Enter the recipient\'s name: ');
const email = await askQuestion('Enter the recipient\'s email: ');
try {
const result = await nylas.messages.send({
identifier: process.env.NYLAS_GRANT_ID,
requestBody: {
subject: subject,
body: body,
to: [{ name: name, email: email }],
},
});
console.log('Result:', result)
} catch (error) {
console.error('Error sending email:', error)
}
rl.close();
};
main();
//Run it with node sendEmail.js
require 'dotenv/load'
require 'nylas'
require 'json'
nylas = Nylas::Client.new(
api_key: ENV["NYLAS_API_KEY"],
api_uri: ENV["NYLAS_API_URI"]
)
print "Enter a subject: "
subject = gets.chomp
print "Enter the body: "
body = gets.chomp
print "Enter the recipient\'s name: "
name = gets.chomp
print "Enter the recipient\'s email: "
email = gets.chomp
request_body = {
subject: subject,
body: body,
to: [{name: name, email: email}]
}
email, _ = nylas.messages.send(identifier: ENV["NYLAS_GRANT_ID"],
request_body: request_body)
puts JSON.pretty_generate(email)
#Run it with ruby sendEmail.rb
from nylas import Client
from dotenv import load_dotenv
import os
load_dotenv()
nylas = Client(
api_key = os.environ.get("NYLAS_API_KEY")
)
subject = input("Enter a subject: ")
body = input("Enter the subject: ")
name = input("Enter the recipient\'s name: ")
email = input("Enter the recipient\'s email: ")
body = {"subject" : subject,
"body": body,
"to":[{"name": name,
"email": email}]}
message = nylas.messages.send(os.environ.get("NYLAS_GRANT_ID"),
request_body = body).data
print(message)
#Run it with python3 sendEmail.py
import com.nylas.NylasClient;
import com.nylas.models.*;
import io.github.cdimascio.dotenv.Dotenv;
import java.io.Console;
import java.util.ArrayList;
import java.util.List;
public class sendEmail {
public static void main(String[] args) throws NylasSdkTimeoutError, NylasApiError {
Dotenv dotenv = Dotenv.load();
NylasClient nylas = new NylasClient.Builder(dotenv.get("NYLAS_API_KEY"))
.apiUri(dotenv.get("NYLAS_API_URI")).build();
Console console = System.console();
System.out.print("Enter a subject: ");
String subject = console.readLine();
System.out.print("Enter the body: ");
String body = console.readLine();
System.out.print("Enter the recipient's name: ");
String name = console.readLine();
System.out.print("Enter the recipient's email: ");
String email = console.readLine();
List<EmailName> emailNames = new ArrayList<>();
emailNames.add(new EmailName(email, name));
SendMessageRequest requestBody = new SendMessageRequest.Builder(emailNames).
subject(subject).
body(body).
build();
Response<Message> response = nylas.messages().
send(dotenv.get("NYLAS_GRANT_ID"), requestBody);
System.out.println(response.getData());
}
}
//Run it with mvn exec:java -Dexec.mainClass=”sendEmail” -Dexec.cleanupDaemonThreads=false
When you use an email API to send emails, there are many advanced features. These features can improve functionality, boost engagement, and give useful insights. Here are some powerful options to consider:
Many applications require sending files alongside emails, such as invoices, reports, or media files. Email APIs often support attachments, allowing you to include these directly in your messages:
Adding Attachments: Most APIs let you attach files. You can do this by giving the file path or by encoding the file in Base64 format. This depends on the language and SDK you are using.
Attachments add depth to your emails, allowing for better communication through supporting documents or multimedia.
Node.js
Ruby
Python
Java
import 'dotenv/config'
import Nylas from 'nylas'
import fs from 'fs';
import path from 'path';
const NylasConfig = {
apiKey: process.env.NYLAS_API_KEY,
apiUri: process.env.NYLAS_API_URI,
}
const nylas = new Nylas(NylasConfig)
const main = async () => {
try {
const attachmentPath = path.resolve('nylas_logo.png');
const fileContent = fs.readFileSync(attachmentPath);
const result = await nylas.messages.send({
identifier: process.env.NYLAS_GRANT_ID,
requestBody: {
subject: "Here's your file",
body: "Please see the attached file",
to: [{ name: "Swag", email: "[email protected]" }],
attachments: [{
content: fileContent.toString('base64'),
contentType: "image/png",
filename: 'nylas_logo.png'
}]
},
});
console.log('Result:', result)
} catch (error) {
console.error('Error sending email:', error)
}
};
main();
require 'dotenv/load'
require 'nylas'
require 'json'
nylas = Nylas::Client.new(
api_key: ENV["NYLAS_API_KEY"],
api_uri: ENV["NYLAS_API_URI"]
)
file = Nylas::FileUtils.attach_file_request_builder("nylas_logo.png")
request_body = {
subject: "Here's your file",
body: "Please see the attached file",
to: [{name: "Swag", email: "[email protected]"}],
attachments: [file]
}
email, _ = nylas.messages.send(identifier: ENV["NYLAS_GRANT_ID"],
request_body: request_body)
puts JSON.pretty_generate(email)
from nylas import Client
from dotenv import load_dotenv
import os
from nylas import utils
load_dotenv()
nylas = Client(
api_key = os.environ.get("NYLAS_API_KEY")
)
attachment = utils.file_utils.attach_file_request_builder("nylas_logo.png")
body = {"subject" : "Here's your file",
"body": "Please see the attached file",
"to":[{"name": "Swag",
"email": "[email protected]"}],
"attachments": [attachment]}
message = nylas.messages.send(os.environ.get("NYLAS_GRANT_ID"),
request_body = body).data
print(message)
import com.nylas.NylasClient;
import com.nylas.models.*;
import io.github.cdimascio.dotenv.Dotenv;
import com.nylas.util.FileUtils;
import java.util.ArrayList;
import java.util.List;
public class sendEmailAttachment {
public static void main(String[] args) throws NylasSdkTimeoutError, NylasApiError {
Dotenv dotenv = Dotenv.load();
NylasClient nylas = new NylasClient.Builder(dotenv.get("NYLAS_API_KEY"))
.apiUri(dotenv.get("NYLAS_API_URI")).build();
CreateAttachmentRequest attachment =
FileUtils.attachFileRequestBuilder("src/main/java/nylas_logo.png");
List<CreateAttachmentRequest> request = new ArrayList<>();
request.add(attachment);
List<EmailName> emailNames = new ArrayList<>();
emailNames.add(new EmailName("[email protected]", "Swag"));
SendMessageRequest requestBody =
new SendMessageRequest.Builder(emailNames).
subject("Here's your file").
body("Please see the attached file").
attachments(request).
build();
Response<Message> response = nylas.messages().
send(dotenv.get("NYLAS_GRANT_ID"), requestBody);
System.out.println(response.getData());
}
}
Personalization boosts user engagement by tailoring the content to individual recipients. Email APIs make it easy to add dynamic fields that adjust based on user data:
Dynamic, personalized emails create a more meaningful connection with recipients, improving open and click-through rates.
To make sure emails look good on all devices and email programs, include both HTML and plain text versions:
Using both formats makes your emails easier to access. It also follows email best practices, which can help with deliverability.
Tracking opens, clicks, and other metrics helps you see how well your emails work. It also gives you insights into user engagement
Node.js
Ruby
Python
Java
import 'dotenv/config'
import Nylas from 'nylas'
const NylasConfig = {
apiKey: process.env.NYLAS_API_KEY,
apiUri: process.env.NYLAS_API_URI,
}
const nylas = new Nylas(NylasConfig)
const main = async () => {
try {
const result = await nylas.messages.send({
identifier: process.env.NYLAS_GRANT_ID,
requestBody: {
subject: "Engagement Email",
body: "Click the <a href='https://nylas.com'>link</a> to learn more!",
to: [{ name: "Swag", email: "[email protected]" }],
tracking_options: {label: "My first tracking",
opens: true, links: true}
},
});
console.log('Result:', result)
} catch (error) {
console.error('Error sending email:', error)
}
};
main();
require 'dotenv/load'
require 'nylas'
require 'json'
nylas = Nylas::Client.new(
api_key: ENV["NYLAS_API_KEY"],
api_uri: ENV["NYLAS_API_URI"]
)
request_body = {
subject: "Engagement Email",
body: "Click the <a href='https://nylas.com'>link</a> to learn more!",
to: [{name: "Swag", email: "[email protected]"}],
tracking_options: {label: "My first tracking", opens: true, links: true}
}
email, _ = nylas.messages.send(identifier: ENV["NYLAS_GRANT_ID"],
request_body: request_body)
puts JSON.pretty_generate(email)
from nylas import Client
from dotenv import load_dotenv
import os
load_dotenv()
nylas = Client(
api_key = os.environ.get("NYLAS_API_KEY")
)
body = {"subject" : "Engagement Email",
"body": "Click the <a href='https://nylas.com'>link</a> to learn more!",
"to":[{"name": "Swag",
"email": "[email protected]"}],
"tracking_options": {"label": "My first tracking",
"opens": True, "links": True}}
message = nylas.messages.send(os.environ.get("NYLAS_GRANT_ID"),
request_body = body).data
print(message)
import com.nylas.NylasClient;
import com.nylas.models.*;
import io.github.cdimascio.dotenv.Dotenv;
import java.util.ArrayList;
import java.util.List;
public class sendEmailTracking {
public static void main(String[] args) throws NylasSdkTimeoutError, NylasApiError {
Dotenv dotenv = Dotenv.load();
NylasClient nylas = new NylasClient.Builder(dotenv.get("NYLAS_API_KEY"))
.apiUri(dotenv.get("NYLAS_API_URI")).build();
List<EmailName> emailNames = new ArrayList<>();
emailNames.add(new EmailName("[email protected]", "Swag"));
TrackingOptions trackingOptions =
new TrackingOptions("My first tracking", true, true, null);
SendMessageRequest requestBody = new SendMessageRequest.Builder(emailNames).
subject("Engagement Email").
body("Click the <a href='https://nylas.com'>link</a> to learn more!").
trackingOptions(trackingOptions).
build();
Response<Message> response = nylas.messages().
send(dotenv.get("NYLAS_GRANT_ID"), requestBody);
System.out.println(response.getData());
}
}
Tracking provides valuable data, enabling you to adjust and optimize email content over time based on actual user interactions.
In order to monitor tracking, we need to utilize Notifications with their corresponding Notification schemas.
Scheduling emails for a specific time or date is important for time-sensitive content. This includes newsletters and promotional campaigns
This feature is particularly useful for marketing, ensuring that users receive content when they’re most likely to engage.
Adding these advanced features to your email process makes your messages more effective. It also improves engagement and gives better insights into user behavior. By using attachments, personalization, tracking, and scheduling, you can create a more impactful and data-driven email strategy.
Node.js
Ruby
Python
Java
import 'dotenv/config'
import Nylas from 'nylas'
import date from 'date-and-time';
const NylasConfig = {
apiKey: process.env.NYLAS_API_KEY,
apiUri: process.env.NYLAS_API_URI,
}
const nylas = new Nylas(NylasConfig)
const now = new Date();
const scheduled = date.addMinutes(now,2);
const main = async () => {
try {
const result = await nylas.messages.send({
identifier: process.env.NYLAS_GRANT_ID,
requestBody: {
subject: "This is a scheduled message",
body: "I sent this email 2 minutes ago",
to: [{ name: "Blag", email: "[email protected]" }],
send_at: (scheduled.getTime() - scheduled.getMilliseconds()) / 1000,
},
});
console.log('Result:', result)
} catch (error) {
console.error('Error sending email:', error)
}
};
main();
require 'dotenv/load'
require 'nylas'
require 'json'
nylas = Nylas::Client.new(
api_key: ENV["NYLAS_API_KEY"],
api_uri: ENV["NYLAS_API_URI"]
)
class Numeric
def minutes; self/1440.0 end
alias :minute :minutes
def seconds; self/86400.0 end
alias :second :seconds
end
d = DateTime.now
d = d + 2.minute
scheduled = DateTime.parse(d.to_s).strftime("%s").to_i
request_body = {
subject: "This is a scheduled message",
body: "I sent this email 2 minutes ago",
to: [{name: "Swag", email: "[email protected]"}],
send_at: scheduled
}
email, _ = nylas.messages.send(identifier: ENV["NYLAS_GRANT_ID"],
request_body: request_body)
puts JSON.pretty_generate(email)
from nylas import Client
from dotenv import load_dotenv
import os
import pendulum
load_dotenv()
nylas = Client(
api_key = os.environ.get("NYLAS_API_KEY")
)
now = pendulum.now()
now = now.add(minutes=2)
body = {"subject" : "This is a scheduled message",
"body": "I sent this email 2 minutes ago",
"to":[{"name": "Swag",
"email": "[email protected]"}],
"send_at": now.int_timestamp
}
message = nylas.messages.send(os.environ.get("NYLAS_GRANT_ID"),
request_body = body).data
print(message)
import com.nylas.NylasClient;
import com.nylas.models.*;
import io.github.cdimascio.dotenv.Dotenv;
import java.util.ArrayList;
import java.util.List;
import java.util.Calendar;
public class sendEmailScheduled {
public static void main(String[] args) throws NylasSdkTimeoutError, NylasApiError {
Dotenv dotenv = Dotenv.load();
NylasClient nylas = new NylasClient.Builder(dotenv.get("NYLAS_API_KEY"))
.apiUri(dotenv.get("NYLAS_API_URI")).build();
List<EmailName> emailNames = new ArrayList<>();
emailNames.add(new EmailName("[email protected]", "Swag"));
Calendar calendar = Calendar.getInstance();
calendar.add(Calendar.MINUTE, 2);
SendMessageRequest requestBody = new SendMessageRequest.Builder(emailNames).
subject("This is a scheduled message").
body("I sent this email 2 minutes ago").
sendAt((int) (calendar.toInstant().getEpochSecond())).
build();
Response<Message> response = nylas.messages().
send(dotenv.get("NYLAS_GRANT_ID"), requestBody);
System.out.println(response.getData());
}
}
To ensure reliable, secure, and high-quality email delivery through an email API, follow these best practices. These guidelines will help optimize deliverability, maintain security, and create a smooth user experience.
Deliverability—ensuring that emails reach recipients’ inboxes rather than spam folders—is critical to any email integration. Here’s how to optimize it:
Email APIs often require sensitive data, so prioritizing security is essential:
Ensuring that your email-sending process is reliable involves handling errors and retries efficiently:
Personalized, well-formatted emails are more engaging and less likely to be flagged as spam:
Tracking API usage and performance is crucial for maintaining a smooth integration:
Test thoroughly to ensure that emails appear as intended and that the API integration is reliable:
Integrating an email API can sometimes involve challenges, especially when dealing with large volumes or various technical requirements. Here are some common issues you might encounter and strategies for troubleshooting them effectively.
Most email APIs enforce rate limits to prevent abuse and ensure consistent performance for all users. Exceeding these limits can result in errors or temporary suspension of requests.
Authentication errors occur when the API credentials are incorrect or expired, often resulting in 401 (Unauthorized) responses.
Invalid email addresses or improperly formatted requests can cause errors when sending emails.
Network issues can disrupt API requests and cause temporary failures in email delivery.
Sometimes, emails with specific content (e.g., large images, special characters) may fail to send or get flagged as spam.
Low deliverability can be a complex issue, often resulting in emails being marked as spam or blocked by certain email providers.
Duplicate emails can occur due to retry logic or unintended resends, which can negatively impact the user experience.
Email APIs often return detailed error responses that can help you identify specific issues and resolve them quickly.
By proactively addressing these common issues and implementing robust error-handling mechanisms, you can ensure a more reliable and user-friendly email-sending experience. Following these troubleshooting steps will help you maintain smooth, consistent email operations and reduce potential disruptions in your application.