Real-Time Email Verification API

package main

import (
  "bytes"
  "encoding/json"
  "fmt"
  "net/http"
  "os"
)

type VerifyRequest struct {
  Email string `json:"email"`
}

type VerifyResult struct {
  Valid       bool    `json:"valid"`
  Score       int     `json:"score"`
  Disposable  bool    `json:"disposable"`
  Role        bool    `json:"role"`
  Suggestion  *string `json:"suggestion"`
  Status      string  `json:"status"`
}

func verifyEmail(email string) (*VerifyResult, error) {
  body, _ := json.Marshal(VerifyRequest{Email: email})
  req, _ := http.NewRequest("POST", "https://api.mailbeam.dev/v1/verify", bytes.NewReader(body))
  req.Header.Set("Authorization", "Bearer "+os.Getenv("MAILBEAM_KEY"))
  req.Header.Set("Content-Type", "application/json")

  resp, err := http.DefaultClient.Do(req)
  if err != nil {
    return nil, err
  }
  defer resp.Body.Close()

  var result VerifyResult
  json.NewDecoder(resp.Body).Decode(&result)
  return &result, nil
}

func handleSignup(email string) error {
  result, err := verifyEmail(email)
  if err != nil || !result.Valid {
    if result != nil && result.Suggestion != nil {
      return fmt.Errorf("did you mean %s?", *result.Suggestion)
    }
    return fmt.Errorf("invalid email address")
  }
  if result.Disposable {
    return fmt.Errorf("temporary email addresses are not accepted")
  }
  return nil
}