Real Time Email Verification API Documentation Release 1.0.17 email-checker.com February 27, 2016
Contents 1 Product Overview 3 1.1 Product Overview............................................ 3 2 Quick Start 5 2.1 Quick Start................................................ 5 3 Features 7 3.1 Features.................................................. 7 4 Technical Specification 11 4.1 Technical Specification.......................................... 11 5 Installation 13 5.1 Installation................................................ 13 6 Configuration And Usage 15 6.1 Configuration And Usage........................................ 15 7 Integration 19 7.1 Integration................................................ 19 8 Plugins 21 8.1 Plug-ins.................................................. 21 9 FAQs 23 9.1 Frequently Asked Questions....................................... 23 10 Status Codes 27 10.1 Email Verification Response Codes For API V1............................. 27 11 Integration Examples 31 11.1 Integration Examples........................................... 31 12 Glossary 49 12.1 Glossary................................................. 49 i
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Note: This is version 1 endpoint documentation maintained for customers migrating from the following providers: email-checker.com emailyoyo.com emailcleansing.com bulkemailverifier.com For customers using our API for the first time, please see our most up to date Email Verification API. Our email verification API will help your business reduce costs by eliminating bad email addresses from entering your information systems. Contents 1
2 Contents
CHAPTER 1 Product Overview 1.1 Product Overview 1.1.1 Why Email Address Verification? Sending emails to non-existent addresses is never a good idea for many reasons including: Damaging the reputation of your ESP infrastructure (IP addresses) Many ESPs will have maximum hard bounce thresholds. Exceed these and your account could be closed. Bad emails in a list negatively affects deliver-ability rates A Block List can keep track of failed deliveries (e.g. bad email address) at a particular domain. Too many failed deliveries can raise some flags thus raising the risk of your email campaign being flagged as spam. Processing hard bounces means wasted time An email sent to a bad or non-existent email address results in a bounce message coming back. Someone or something (e.g. automated software) is required to remove the bounces from a email list so as to avoid sending to bad addresses next time. Tip: Cleansing bad emails from a list using email verification technology before embarking on an emailing campaign significantly reduces the above challenges. 1.1.2 Product Description emailhippo.com offers data cleansing services specifically for email addresses. Offering a fully cloud based solution, emailhippo.com provides fast, reliable and accurate email verification. With unrivalled coverage in all areas (including traditionally hard to verify email addresses such as Hotmail and Yahoo), emailhippo.com is the natural choice for customers requiring good coverage in their applications for both B2B and B2C email addresses. 1.1.3 Possible Applications for Email Address Verification API If you operate a lead generation web site, blog or forum make it harder for users to sign up with false emails. For e-commerce checkouts, make sure customers receive their order notifications by preventing invalid emails from being entered. If your call centre takes email addresses as part of the customer contact data, real-time verification can greatly reduce the amount of incorrectly keyed emailed addresses. 3
For software vendors where email addresses are captured as part of the on-boarding process, integrate full email verification as a value-add for your service. With emailhippo.com, there is no need any more to take incorrect email addresses and wait for them to bounce! 1.1.4 How To Get Started To get started request a trial key. 4 Chapter 1. Product Overview
CHAPTER 2 Quick Start 2.1 Quick Start This quick start guide is designed to get you up and running as fast as possible. Please follow the steps below in sequence: 2.1.1 1) Get a License Key Request a trial key. 2.1.2 2) Try it! Plug your license key into the following https://api1.27hub.com/api/a/v1?key=insertyourlicensekey&email=test@tester.com Paste the url above into your browser and watch the response come back as follows: { "status":"bad", "additionalstatus":"mailboxdoesnotexist", "emailaddressprovided":"test@tester.com", "emailaddresschecked":"test@tester.com", "emailaddresssuggestion":"" Note: Internet Explorer may prompt to download the file instead of simply displaying it on screen. This is a quirk of Internet Explorer and not an issue with the API. We do not recommend Internet Explorer for testing with the API. Instead, use Chrome or Firefox - both will display the results on screen correctly! 2.1.3 3) Next Steps Configuration And Usage Integration 5
6 Chapter 2. Quick Start
CHAPTER 3 Features 3.1 Features 3.1.1 > 99.9% Service Availability Fully load balanced and automatic fail-over systems dispersed across multiple data centers in multiple regions deliver enterprise grade resilience. 3.1.2 Fanatical Service Quality Management (SQM) emailhippo.com operational staff obsessively monitor services to ensure the best possible uptime and coverage. Uptime and functional correctness is actively monitored on a minute by minute basis from multiple data centers dispersed across North America, Europe and South East Asia. 3.1.3 Multi Factor Verification Progressive verification using multiple verification processes including: Syntax checking DNS checking Mailbox checking 3.1.4 Unrivalled Coverage With more than 5 years experience and the benefit of owning our own software stack, emailhippo.com has refined its services over the years to provide good coverage not only of the easier B2B domains but also the more technically tricky B2C domains including: Hotmail Yahoo AOL Yandex 7
3.1.5 Unrivalled Integration RESTful endpoints integrate with pretty much anything these days. emailhippo.com not only supports server to server integration over REST but server to client integration with full support for CORS. CORS is available in most modern web browsers and allows rich, client side development using only HTML and JavaScript (jquery or AngularJS recommended). See Integration for tested integration examples using a wide range of languages including PHP, Java,.NET, jquery and AngularJS). 3.1.6 Spam Trap Detection After many years R&D, emailhippo.com has developed various secret sauces that can effectively detect and eliminate spam traps from several well known Block List. 3.1.7 Disposable Email Address Detection Detect and eliminate DEA. 3.1.8 Unrivalled Performance Strategic data centers in North America and Europe, aggressive caching and cloud based auto-scaling deliver outstanding performance. Typical queries are answered between 0.2 to 1.5 seconds. Note: See Technical Specification 3.1.9 API Based Email Verification Every plan includes authentication systems based on ACL and License Key based access. Domain based ACL authentication is typically used for client script integrations (e.g. jquery or AngularJS). Domain licenses are tied into a single domain (e.g. www.mydomain.com). License Key based authentication is typically used for server to server integrations. 3.1.10 Error Correction No more fat finger syndrome! Our API has an optional feature to remove certain invalid characters such as spaces, slashes etc. 3.1.11 Common Typo Handling emailhippo.com also searches for common typos and suggest alternatives. E.g. jim99@hotmail.cm is more likely to be jim99@hotmail.com so emailhippo.com will validate what the user has entered, but provide you with the more likely alternative suggestion too. 8 Chapter 3. Features
3.1.12 On Screen Reporting Every account comes with a secure online portal for customers to view their current and historic usage via simple, user friendly donut charts. 3.1.13 Thoughtful Versioning Endpoints are versioned. This means that emailhippo.com can continue to release new functionality without breaking existing clients committed to integrating with our systems on legacy endpoints. 3.1.14 What it does emailhippo.com is used to check email addresses in real-time. Not only are syntax and domain checked, but that the user mailbox is available too. This is the only way to know for sure if an email address is valid. Additionally identified as part of the email verification process is extra information including: DEA. Spam Trap. 3.1.15 How it works Email addresses are verified using various filters and processes. As a high level overview, an email address submitted for verification goes thorough the following filters: Syntax A basic inspection of the syntax of the email address to see if it looks valid. Work is done only using server CPU (Central Processing Unit) based on simple pattern matching algorithms. DNS A Verifies a domain exists in DNS. Domains that do not exist in DNS cannot have mail servers or email boxes. DNS checks are performed over the network. DNS MX Verify MX records using DNS. Domains that do not have MX records, have no mail servers and therefore no valid email boxes. MX checks are performed over the network. MailBox Verify email boxes with SMTP checks. Connect to mail server and perform SMTP protocol to verify if mail box exists. This is the deepest level of verification. It is performed over the network. 3.1. Features 9
10 Chapter 3. Features
CHAPTER 4 Technical Specification 4.1 Technical Specification 4.1.1 Infrastructure Manufacturer emailhippo.com Uptime > 99.9% Response time >0.2seconds < 8 seconds. Typical response time 0.7 seconds. Throughput and concurrency > 100 TPS (Transactions Per Second) Integration RESTful GET over HTTP(S) Authentication Key or Domain based ACL (Access Control List) Infrastructure Geographically dispersed data centers, auto load balance / failover 4.1.2 Application Syntax checking? DNS A checking? DNS MX checking Mailbox checking Reporting / charts? Versioning supported? B2B (Business to Business) coverage? Hotmail coverage? Yahoo coverage? AOL coverage? Yandex coverage? Secure? Spam trap detection? Illegal character detection Typo detection DEA (Disposable Email Address) detection? Reporting charts Server to browser client supported? Server to server supported? CORS (Cross-Origin Resource Sharing)? yes yes yes yes yes yes yes yes yes yes yes yes. HTTPS supported. partial yes yes yes yes yes yes yes 11
12 Chapter 4. Technical Specification
CHAPTER 5 Installation 5.1 Installation There is no software to install. emailhippo is Software as a Service exposed as a simple RESTful service that is available to anything connected to The Internet. 13
14 Chapter 5. Installation
CHAPTER 6 Configuration And Usage 6.1 Configuration And Usage 6.1.1 Authentication Each call to the API must be authenticated. Authentication with the API is performed by either: ACL. License Key. 6.1.2 Accessing the API using key authentication Access the API at: https://api1.27hub.com/api/a/v1?key=yourapikey&email=test@tester.com Sending the following parameters :- Figure 1 - REST Request Variables Parameter Value key your unique API key supplied by us required email the email address to be validated required correct 1 - this will remove certain invalid characters. 0 - this will leave the email untouched. optional Note: Need a license key? Click here. 6.1.3 Accessing the API using ACL authentication https://api1.27hub.com/api/b/v1?email=test@tester.com 15
Note: For ACL based authentication, it is not necessary to include the license key in the request. Other parameters (e.g. correct ) are supported as in the key based example as in Figure 1 - REST Request Variables. 6.1.4 Responses Note: For a full definition of possible responses, see Email Verification Response Codes For API V1. You will receive back the following values in the response. Figure 2 - Responses Response Description Example values status The validation result Ok, Bad, Unknown additionalstatus Additional information for BAD and UNKNOWN results NoMxServers- Found emailaddressprovided The exact email address passed to the API including obvious typos and test@tester.com errors emailaddress- The actual email address validated test@tester.com Checked emailaddresssuggestion A suggested alternative if a common typo was noticed e.g. if fred@hotmail.cm was provided Note: Example response for email address test@tester.com fred@hotmail.com The URL passed to the API is :- https://api1.27hub.com/api/a/v1?key=yourapikey&email=test@tester.com The response would be :- { "status":"bad", "additionalstatus":"mailboxdoesnotexist", "emailaddressprovided":"test@tester.com", "emailaddresschecked":"test@tester.com", "emailaddresssuggestion":"" 6.1.5 The correct Parameter Optionally, you can also use the correct parameter to remove certain invalid characters such as spaces, slashes, square brackets etc. Example using the correct parameter. The user enters an email address john99]@gmail.com Here is the API call that would be made :- http://api1.27hub.com/api/a/v1?key=yourapikey&email=john99]@gmail.com&correct=1 emailhippo.com will automatically remove the invalid character ] and send the corrected version through for validation. Example results based on the above API call :- 16 Chapter 6. Configuration And Usage
{ "status":"ok", "additionalstatus":"none", "emailaddressprovided":"john99]@gmail.com", "emailaddresschecked":"john99@gmail.com", "emailaddresssuggestion":"" 6.1.6 Additional Status Information When an email address is returned with a status of Bad or Unknown we return the detailed reason as part of the response in the additionalstatus value. For a full list of additional status values, please refer to Email Verification Response Codes For API V1. 6.1.7 Sandbox A sandbox environment is available to assist customers with testing, evaluation and integration. The sandbox url is: https://api1.27hub.com:443/api/a/v1/sandbox There is no charge for use and your live quota is not affected. No emails are verified in the sandbox and responses are hard coded. For a full list of hard coded test cases, please see here. 6.1.8 Firewall If you need to enable firewall rules based on IP addresses, you will need to add the following addresses, for ports 80 and 443, to y 23.96.209.155 23.98.64.158 191.235.208.12 137.117.224.218 6.1. Configuration And Usage 17
18 Chapter 6. Configuration And Usage
CHAPTER 7 Integration 7.1 Integration See comprehensive Integration Examples showing diverse examples of server and client languages. 19
20 Chapter 7. Integration
CHAPTER 8 Plugins 8.1 Plug-ins 8.1.1 jquery Validation Plug-in jquery Plugin is a generic jquery library has been constructed to use RESTful email verification services from www.email-checker.com. Grab the jquery-plugin over at GitHub. 21
22 Chapter 8. Plugins
CHAPTER 9 FAQs 9.1 Frequently Asked Questions 9.1.1 How can I get a key? Click here to request a license key. 9.1.2 How do I call the API? Make a simple GET request to the endpoint. For example, to query email address anyone@yourdomain.com with license key ABCD1234 call: https://api1.27hub.com/api/a/v1?key=abcd1234&email=anyone@yourdomain.com 9.1.3 What comes back from the API? A JSON based response similar to: { "status":"bad", "additionalstatus":"mailboxdoesnotexist", "emailaddressprovided":"anyone@yourdomain.com", "emailaddresschecked":"anyone@yourdomain.com", "emailaddresssuggestion":"" Note: For a detailed explanation of response codes, please see Email Verification Response Codes For API V1. 9.1.4 How can I integrate the API with my solution? We have tested, detailed integration examples using a wide range of technologies and languages including Java, PHP,.NET, jquery and Angular. Please see Integration for more information. 23
9.1.5 How reliable is the API? > 99.9% average availability. 9.1.6 Does the system get slower when it s busy? No. All infrastructure is hosted in cloud based platforms with automatic scaling enabled. Automatic scaling kicks in at busy times to provide more hardware resources to meet demand. 9.1.7 Can it do Hotmail? Yes. 9.1.8 Can it do Yahoo? Yes. Based on our own internal testing emailhippo.com is currently the only email verification service to offer effective and repeatable coverage for Yahoo addresses. 9.1.9 Can it do Yandex? Yes it can. 9.1.10 Can it find spam traps? Partially. A Spam Trap is a moving target. In theory (and indeed in practice) anyone can setup a Block List and start putting spam traps into the wild. emailhippo.com has Spam Trap detection capabilities that covers several of the well known block lists. Whilst it is not possible to deliver 100% coverage of all spam traps from all block lists, emailhippo.com provides the best Spam Trap detection capabilities available. 9.1.11 How does it work? At a basic conceptual level, the process of verifying email addresses is very simple. Google for Send email using telnet for a quick and general overview of how it s done. To verify an email address without sending an email, simply go as far as the RCPT TO stage and parse the response code. That s the easy bit and can be accomplished in just a couple of dozen lines of a PHP script! The hard bit is dealing with mail services that are intrinsically configured to work against the process of email verification or any similar SMTP based activity. The reason that any email / SMTP process is difficult from a client perspective is that mail services need to protect themselves from an ever increasing landscape of abuse including spam and DDoS attacks. emailhippo.com s strength in dealing with the hard bit of email verification comes from years of experience in doing email verification together with our complete ownership of our SMTP verification software stack together with an extensive cloud based infrastructure. That s why emailhippo.com can do the hard bits best and offer outstanding coverage on the more difficult domains such as Yahoo and Hotmail. 24 Chapter 9. FAQs
9.1.12 Can I get blacklisted using this API? No. It s emailhippo.com infrastructure that does the work. 9.1.13 Will anyone know that I am verifying their email address? No. It s emailhippo.com infrastructure that does the work. 9.1.14 Your service says an address is OK and I know it s Bad (or vice versa)? emailhippo.com queries mail servers in real time. Mail servers respond with one of 2 possible answers for a given email address: Yes, the email address exists - SMTP code 2xx No, the email address doe not exist - SMTP code 5xx emailhippo.com uses the above response codes to determine if an email address is valid or not and reports this back to you. This method of determining email address validity works in >99% cases. However, nothing is guaranteed. In a small number of cases it is possible for a mail server to report one thing on email verification and do something different on trying to deliver an email to the email address verified. At the time of verification the mail server would have reported Yes/No, however this may have been due to an error within the target mail server and the opposite may have been true. This is rare, but it can happen. If this was a temporary error within the target mail server, please note that this result may be remembered by our system for a few hours. For another example, say we take an email address of this.seems.to.verify@hotmail.com to send to. We are sending from a fictitious email address my.sending.account@gmail.com. this.seems.to.verify@hotmail.com reports with status code of OK from the email verification API. However, when you send an email to this.seems.to.verify@hotmail.com, the email bounces. Further inspection of the bounced email Non Delivery Report (NDR) headers show something like the following: Delivered-To: my.sending.account@gmail.com Received: by 10.107.174.134 with SMTP id n6csp24867ioo; Sat, 6 Jun 2014 03:57:29-0800 (PST) X-Received: by 10.202.4.5 with SMTP id 5mr1335105oie.22.1417867048986; Sat, 06 Jun 2014 03:57:28-0800 (PST) Return-Path: <> Received: from SNT004-OMC2S34.hotmail.com (snt004-omc2s34.hotmail.com. [65.55.90.109]) by mx.google.com with ESMTPS id ws5si21632759obb.102.2014.12.06.03.57.28 for <my.sending.account@gmail.com> (version=tlsv1.2 cipher=ecdhe-rsa-aes128-sha bits=128/128); Fri, 6 Jun 2014 03:57:28-0800 (PST) Received-SPF: none (google.com: SNT004-OMC2S34.hotmail.com does not designate permitted sender hosts) Authentication-Results: mx.google.com; spf=none (google.com: SNT004-OMC2S34.hotmail.com does not designate permitted sender hosts Received: from SNT004-MC2F40.hotmail.com ([65.55.90.73]) by SNT004-OMC2S34.hotmail.com over TLS secur Fri, 6 Jun 2014 03:57:28-0800 From: postmaster@hotmail.com To: my.sending.account@gmail.com Date: Fri, 6 Jun 2014 03:57:28-0800 MIME-Version: 1.0 Content-Type: multipart/report; report-type=delivery-status; boundary="9b095b5adsn=_01d010aabce2c5cc0008c930snt004?mc2f40.ho" 9.1. Frequently Asked Questions 25
X-DSNContext: 335a7efd - 4481-00000001 - 80040546 Message-ID: <mjz7zgtpi00029250@snt004-mc2f40.hotmail.com> Subject: Delivery Status Notification (Failure) Return-Path: <> X-OriginalArrivalTime: 06 Jun 2014 11:57:28.0142 (UTC) FILETIME=[CEAD2EE0:01D0114B] This is a MIME-formatted message. Portions of this message may be unreadable without a MIME-capable mail program. --9B095B5ADSN=_01D010AABCE2C5CC0008C930SNT004?MC2F40.ho Content-Type: text/plain; charset=unicode-1-1-utf-7 This is an automatically generated Delivery Status Notification. Delivery to the following recipients failed. this.seems.to.verify@hotmail.com The email header of the NDR shows that Hotmail thinks the email address is invalid as far as sending to this address is concerned. However, Hotmail reports that the same email address is valid as far as the email verification activity performed by emailhippo.com. The discrepancy in verification results versus mail send is with the Hotmail infrastructure reporting one thing but doing the exact opposite. This behaviour occasionally (particularly from Hotmail) is seen in a small amount of cases and is attributable to internal Hotmail (or other mail services) system anomalies. The majority (>99%) of email verification status versus mail send is consistent. However there are some edge cases caused by system faults in the mail service providers themselves. For these small number of cases, there is nothing that can be done at the email verification stage. 26 Chapter 9. FAQs
CHAPTER 10 Status Codes 10.1 Email Verification Response Codes For API V1 A response is a message consisting of a standard HTTP header and body. The body of the message contains the detail of the message (e.g. the JSON data with email verification detail). The header of the message contains general HTTP information such as HTTP status codes. Response Body Content Main Status Response Codes Additional Status Codes Response Header HTTP Status Codes 10.1.1 Response Body Content Main Status Response Codes Ok Verification passes all checks including Syntax, DNS, MX, Mailbox, Deep Server Configuration, Grey Listing Bad Verification fails checks for definitive reasons (e.g. mail box does not exist) Unknown Conclusive verification result cannot be achieved due to mail server configuration or anti-spam measures. See table Additional Status Codes. Additional Status Codes None No additional information is available. This status differs from a TransientNetworkFault as it should not be retried (the result will not change). There are a few known reasons for this status code for example the target mx record uses Office 365 or a mail provider implementing custom mailbox shutdowns. AtSignNotFound The required @ sign is not found in email address. 27
DomainIsInexistent The domain (i.e. the bit after the @ character) defined in the email address does not exist, according to DNS records. A domain that does not exist cannot have email boxes. A domain that does not exist cannot have email boxes. DomainIsWellKnownDea The domain is a well known Disposable Email Address DEA. There are many services available that permit users to use a one-time only email address. Typically, these email addresses are used by individuals wishing to gain access to content or services requiring registration of email addresses but same individuals not wishing to divulge their true identities (e.g. permanent email addresses). DEA addresses should not be regarded as valid for email send purposes as it is unlikely that messages sent to DEA addresses will ever be read. MailboxFull The mailbox is full. Mailboxes that are full are unable to receive any further email messages until such time as the user empties the mail box or the system administrator grants extra storage quota. Most full mailboxes usually indicate accounts that have been abandoned by users and will therefore never be looked at again. We do not recommend sending emails to email addresses identified as full. MailboxDoesNotExist The mailbox does not exist. 100% confidence that the mail box does not exist. NoMxServersFound There are no mail servers defined for this domain, according to DNS. Email addresses cannot be valid if there are no email servers defined in DNS for the domain. ServerDoesNotSupportInternationalMailboxes The server does not support international mailboxes. International email boxes are those that use international character sets such as Chinese / Kanji etc. International email boxes require systems in place for Punycode translation. Where these systems are not in place, email verification or delivery is not possible. For further information see Punycode. ServerIsCatchAll The server is configured for catch all and responds to all email verifications with a status of Ok. Mail servers can be configured with a policy known as Catch All. Catch all redirects any email address sent to a particular domain to a central email box for manual inspection. Catch all configured servers cannot respond to requests for email address verification. Success Successful verification. 100% confidence that the mail box exists. TooManyAtSignsFound Too many @ signs found in email address. Only one @ character is allowed in email addresses. Unknown The reason for the verification result is unknown. TransientNetworkFault A temporary network fault occurred during verification. Please try again later. Verification operations on remote mail servers can sometimes fail for a number of reasons such as loss of network connection, remote servers timing out etc. One other possible cause of a temporary fault is Grey Listing. 28 Chapter 10. Status Codes
These conditions are usually temporary. Retrying verification at a later time will usually result in a positive response from mail servers. Please note that setting an infinite retry policy around this status code is inadvisable as there is no way of knowing when the issue will be resolved within the target domain or the grey listing resolved, and this may affect your daily quota. PossibleSpamTrapDetected A possible spam trap email address or domain has been detected. Spam traps are email addresses or domains deliberately placed on-line in order to capture and flag potential spam based operations. Our advanced detection heuristics are capable of detecting likely spam trap addresses or domains known to be associated with spam trap techniques. We do not recommend sending emails to addresses identified as associated with known spam trap behaviour. Sending emails to known spam traps or domains will result in your ESP being subjected to email blocks from a DNS Block List.. An ESP cannot tolerate entries in a Block List (as it adversely affects email deliver-ability for all customers) and will actively refuse to send emails on behalf of customers with a history of generating entries in a Block List. 10.1.2 Response Header HTTP Status Codes In additional to the application level codes (see Main Status Response Codes and Additional Status Codes) returned in the HTTP message body, HTTP status codes are returned in the HTTP header. 200 Call successful. 304 The cached copy on the client is up to date. Resource not transferred. Use this with client side If-Modified-Since request for efficient caching. Caching is available for both HTTP and HTTPS options. 400 Bad request. The server could not understand the request. Perhaps missing a license key or an email to check? Conditions that lead to this error are: No license key supplied, no email address supplied, email address > 255 characters, license key in incorrect format. 401 Possible reasons: The provided license key is not valid, the provided license key has expired, the provided license key is not permitted for use from this domain, you have reached your quota capacity for this account, this account has been disabled. 500 An error occurred on the server. Possible reasons are: license key validation failed or a general server fault. 10.1. Email Verification Response Codes For API V1 29
30 Chapter 10. Status Codes
CHAPTER 11 Integration Examples 11.1 Integration Examples 11.1.1 Server Examples PHP <?php // URL which should be requested $url = 'http://api1.27hub.com/api/a/v1'; $apikey = 'YOUR API KEY'; // API Key $email = 'Email Address to Test'; // Email to test // json String for request $url.= "?email=$email&key=$apikey"; // Initializing curl $ch = curl_init( $url ); if($ch == false) { die ("Curl failed!"); else { // Configuring curl options $options = array( CURLOPT_RETURNTRANSFER => true, CURLOPT_HTTPHEADER => array('content-type: application/json') ); // Setting curl options curl_setopt_array( $ch, $options ); // Getting results $result = curl_exec($ch); // Getting json result string // display JSON data 31
echo "$result";?> C# #region Usings using System; using System.IO; using System.Net; #endregion /// <summary> /// The program. /// </summary> internal class Program { #region Constants /// <summary> /// The api url. /// </summary> private const string ApiUrl = @"http://api1.27hub.com/api/a/v1"; /// <summary> /// 0 = ApiUrl /// 1 = Email address to query /// 2 = API Key /// </summary> private const string QueryFormatString = @"{0?email={1&key={2"; /// <summary> /// The your api key. /// </summary> /// <remarks> /// /ENTER YOUR API KEY HERE/ /// </remarks> private const string YourAPIKey = @"<!-- ENTER A VALID KEY HERE-->"; #endregion #region Methods /// <summary> /// The main program entry point. /// </summary> /// <param name="args"> /// The args. /// </param> private static void Main(string[] args) { Console.WriteLine("Input email address to verify"); var readline = Console.ReadLine(); 32 Chapter 11. Integration Examples
Console.WriteLine(string.Empty); var requesturl = string.format(queryformatstring, ApiUrl, readline, YourAPIKey); var myrequest = (HttpWebRequest)WebRequest.Create(requestUrl); WebResponse webresponse = null; try { webresponse = myrequest.getresponse(); using (var reader = new StreamReader(webResponse.GetResponseStream())) { var jsonstring = reader.readtoend(); Console.ForegroundColor = ConsoleColor.Green; Console.WriteLine("Result:"); Console.WriteLine(jsonString); Console.ResetColor(); Console.WriteLine("Press <Enter> to continue.."); Console.ReadLine(); catch (Exception exception) { Console.WriteLine("An error occured:"); Console.ForegroundColor = ConsoleColor.Red; Console.WriteLine("Exception reported: {0", exception.message); Console.ResetColor(); Console.WriteLine("Press <Enter> to continue.."); Console.ReadLine(); finally { if (webresponse!= null) { webresponse.dispose(); #endregion VB.net Imports System.IO Imports System.Net ''' <summary> ''' The program. ''' </summary> Friend Class Program #Region "Constants" 11.1. Integration Examples 33
''' <summary> ''' The api url. ''' </summary> Private Const ApiUrl As String = "http://api1.27hub.com/api/a/v1" ''' <summary> ''' 0 = ApiUrl ''' 1 = Email address to query ''' 2 = API Key ''' </summary> Private Const QueryFormatString As String = "{0?email={1&key={2" ''' <summary> ''' The your api key. ''' </summary> ''' <remarks> ''' /ENTER YOUR API KEY HERE/ ''' </remarks> Private Const YourAPIKey As String = "<!-- ENTER A VALID KEY HERE-->" #End Region #Region "Methods" ''' <summary> ''' The main program entry point. ''' </summary> ''' <param name="args"> ''' The args. ''' </param> Private Shared Sub Main(args As String()) Console.WriteLine("Input email address to verify") Dim readline = Console.ReadLine() Console.WriteLine(String.Empty) Dim requesturl = String.Format(QueryFormatString, ApiUrl, readline, YourAPIKey) Dim myrequest = DirectCast(WebRequest.Create(requestUrl), HttpWebRequest) Dim webresponse As WebResponse = Nothing Try webresponse = myrequest.getresponse() Using reader = New StreamReader(webResponse.GetResponseStream()) Dim jsonstring = reader.readtoend() Console.ForegroundColor = ConsoleColor.Green Console.WriteLine("Result:") Console.WriteLine(jsonString) Console.ResetColor() Console.WriteLine("Press <Enter> to continue..") Console.ReadLine() End Using Catch exception As Exception 34 Chapter 11. Integration Examples
End Sub Finally End Try Console.WriteLine("An error occured:") Console.ForegroundColor = ConsoleColor.Red Console.WriteLine("Exception reported: {0", exception.message) Console.ResetColor() Console.WriteLine("Press <Enter> to continue..") Console.ReadLine() If webresponse IsNot Nothing Then webresponse.dispose() End If #End Region End Class Java / Company: (c) 2016, email-checker.com (https://www.emailhippo.com) File name: java.v1_key_acl Version: 1.0.20140827.0 Version control: - 1.0.20140827.0 - initial release Date: August 2014 Description: Demonstrates how to call a RESTful service @ //api1.27hub.com/api/a/v1 using java. This example requires a valid key to work correctly. License: Apache 2.0 (https://www.apache.org/licenses/license-2.0) / import java.io.bufferedreader; import java.io.ioexception; import java.io.inputstreamreader; import java.net.httpurlconnection; import java.net.url; import java.util.scanner; import java.util.logging.level; import java.util.logging.logger; public class Program { 11.1. Integration Examples 35
/ The URL which should be requested / private static final String ApiUrl = "http://api1.27hub.com/api/a/v1"; / Query string for request %1$s = ApiUrl %2$s = Email address to query %3$s = API Key / private static final String QueryFormatString = "%1$s?email=%2$s&key=%3$s"; / Your API Key / private static final String YourAPIKey = "/ ENTER A VALID KEY HERE /"; / The main program entry point @param args the command line arguments @throws IOException If the server does not return a success response / public static void main(string[] args) { System.out.println("Input email address to verify"); // Create a scanner to read in the requested email address Scanner in = new Scanner(System.in); String readline = in.next(); try { // Format the request url to the correct structure for the request URL requesturl = new URL(String.format(QueryFormatString, ApiUrl, readline, Y // Open a connection to the website HttpURLConnection myrequest = (HttpURLConnection) requesturl.openconnection( // Set the type to HTTP GET myrequest.setrequestmethod("get"); // Create a new buffered reader to read the response back from the server BufferedReader reader = new BufferedReader( new InputStreamReader(myRequest.getInputStream())); String inputline; StringBuilder response = new StringBuilder(); // Read in the response line from the server while ((inputline = reader.readline())!=null ) { response.append(inputline); // Close the reader reader.close(); 36 Chapter 11. Integration Examples
// Output the result to console System.out.println(response.toString()); catch (IOException ex) { Logger.getLogger(Program.class.getName()).log(Level.SEVERE, null, ex); Python ########################################################################################### # Company: # (c) 2016, emailhippo.com (https://www.emailhippo.com) # # Version: # 1.0.20140827.0 # # Version control: # - 1.0.20140827.0 - initial release # # Date: # August 2014 # # Description: # Demonstrates how to call a RESTful service @ //api1.27hub.com/api/a/v1 # using Python # # This example requires a valid key to work correctly. # # License: # Apache 2.0 (https://www.apache.org/licenses/license-2.0) ########################################################################################### # Import the module for handling the http request import urllib.request # The url for the service ApiUrl = "http://api1.27hub.com/api/a/v1" # The format of the full query string QueryFormatString = "{0?email={1&key={2" # The API key provided for your account goes here YourAPIKey = "<!-- ENTER A VALID KEY HERE-->" # Read in the user input readline = input("enter Email:\n") # Format the full url and make the http GET request and read the response response = urllib.request.urlopen(queryformatstring.format(apiurl, readline, YourAPIKey)).read() # Print the response print(response) 11.1. Integration Examples 37
PERL ########################################################################################### # Company: # (c) 2016, emailhippo.com (https://www.emailhippo.com) # # File name: # Program.pl # # Version: # 1.0.20140828.0 # # Version control: # - 1.0.20140828.0 - initial release # # Date: # August 2014 # # Description: # Demonstrates how to call a RESTful service @ //api.27hub.com/api/a/v1 # using Perl using client side only calls. # # This example requires a valid key to work correctly. # # License: # Apache 2.0 (https://www.apache.org/licenses/license-2.0) ########################################################################################### use LWP; # The url for the service $ApiUrl = "http://api1.27hub.com/api/a/v1"; # The format of the full query string $QueryFormatString = "%s?email=%s&key=%s"; print "Enter Email:\n"; $readline = <STDIN>; # The API key provided for your account goes here $YourAPIKey = "<!-- ENTER A VALID KEY HERE-->"; # Format the url request $requesturl = sprintf $QueryFormatString, $ApiUrl, $readline, $YourAPIKey; # Make the request against the REST service $browser = LWP::UserAgent->new; $response = $browser->get($requesturl); # Print the response print $response->content; 11.1.2 Client Examples jquery (domain ACL) 38 Chapter 11. Integration Examples
Note: Demonstrates how to call a RESTful service @ //api1.27hub.com/api/a/v1 using jquery, client side only calls. <!DOCTYPE html> <!-- Company: (c) 2016, emailhippo.com (https://www.emailhippo.com) File name: v1_domain_acl.html Version: 1.0.20140827.0 Version control: - 1.0.20140827.0 - initial release Date: August 2014 Description: Demonstrates how to call a RESTful service @ //api1.27hub.com/api/a/v1 using jquery, client side only calls. This example requires a domain ACL and hosting at specified domain to work correctly. License: Apache 2.0 (https://www.apache.org/licenses/license-2.0) --> <html lang="en" xmlns="http://www.w3.org/1999/xhtml"> <head> <meta charset="utf-8" /> <title>emailhippo.com : Domain Access Control List Sample.</title> <style type="text/css">.statusunknown{ color: #c1c72c;.statusok{ color: #009933;.statusBad,.errorMsg{ color: #ff0000; input[type='text']{ width: 300px; p label {display: inline-block; width: 60px; </style> <script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script> </head> <body> <h1>emailhippo.com : email verification demo using domain access control list aut <h2>about</h2> <p>this example shows how to perform email verification using just client side sc <h2>how to run this sample</h2> <p>two things are needed to run this sample:</p> <ol> <li>a domain <abbr title="access Control List">ACL</abbr> is required fro <li>web hosting for www.yourdomain.com.</li> </ol> <p>please upload this sample to your web host in order to run.</p> <h2>key features</h2> <ul> 11.1. Integration Examples 39
<li>compatible with all modern browsers</li> <li>uses jquery 1.11.1</li> <li>no server side scripting required</li> </ul> <hr/> <h2>try it</h2> <p> <label for="email">email:</label> <input type="text" name="email" id="email" /> <input type="button" name="submit" id="submit" value="verify"/> </p> <div id="validationresult"></div> <!--Result output here--> <script> /nest key logic inside document.ready to ensure functionality only avail $(function () { console.log("ready!"); $('#submit').click(function () { var emailtext = $('#email').val(); if (emailtext.length == 0) { $('#validationresult').html("<span class='errorms return; $('#validationresult').html("verifying..."); var emailverifyapi = '//api1.27hub.com/api/a/v1?email=' + ); ); /execute remote request to perform email verification. A $.getjson(emailverifyapi, {).done(function (data) { reportresult(data); ).fail(function (jqxhr, textstatus, error) { var err = textstatus + ", " + error; console.log("request failed: " + err); );; /Output result to the 'validationresult' div element/ function reportresult(data) { var status = data['status'].tolowercase(); // get 'status' from R var additionalstatus = data['additionalstatus']; // get 'addition var message = data['message']; // if there is an error (e.g. lice console.log(status); console.log(additionalstatus); console.log(message); var statushtml; // if there is an error message, show here if (message!= null && message!= '') { statushtml = "<span class='errormsg'>error. Message='" + else { 40 Chapter 11. Integration Examples
// map REST response data to presentation messages. switch (status) { case 'ok': statushtml = "<span class='statusok'>emai break; case 'bad': statushtml = "<span class='statusbad'>ema break; default: statushtml = "<span class='statusunknown' break; </html> </body> </script> console.log(statushtml); // present the result on screen $('#validationresult').html(statushtml); jquery (license key) Note: Demonstrates how to call a RESTful service @ //api1.27hub.com/api/a/v1 using jquery using client side only calls <!DOCTYPE html> <!-- Company: (c) 2016, www.emailhippo.com.com (https://www.emailhippo.com) File name: v1_key_acl.html Version: 1.0.20140827.0 Version control: - 1.0.20140827.0 - initial release Date: August 2014 Description: Demonstrates how to call a RESTful service @ //api1.27hub.com/api/a/v1 using jquery using client side only calls. This example requires a valid key to work correctly. License: Apache 2.0 (https://www.apache.org/licenses/license-2.0) 11.1. Integration Examples 41
--> <html lang="en" xmlns="http://www.w3.org/1999/xhtml"> <head> <meta charset="utf-8" /> <title>27hub.com : License Key Sample.</title> <style type="text/css">.statusunknown { color: #c1c72c; </head> <body>.statusok { color: #009933;.statusBad,.errorMsg { color: #ff0000; input[type='text'] { width: 300px; p label { display: inline-block; width: 60px; </style> <script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script> <h1>27hub.com : email verification demo using simple key authentication with jquery.</h1> <h2>about</h2> <p>this example shows how to perform email verification using just client side scripting <h2>how to run this sample</h2> <p>this page can be hosted anywhere (i.e. any web host or platform). The only thing neede <h2>key features</h2> <ul> <li>compatible with all modern browsers</li> <li>uses jquery 1.11.1</li> <li>no server side scripting required</li> </ul> <hr /> <h2>try it</h2> <p> <label for="key">key:</label> <input type="text" id="key" name="key" tabindex="1" maxlength="20" /> </p> <p> <label for="email">email:</label> <input type="text" name="email" id="email" tabindex="2" /> <input type="button" name="submit" id="submit" tabindex="3" value="verify" /> </p> <div id="validationresult"></div> <!--Result output here--> <script> /nest key logic inside document.ready to ensure functionality only avail $(function () { console.log("ready!"); $('#submit').click(function () { 42 Chapter 11. Integration Examples
var emailtext = $('#email').val(); // get key from text b var keytext = $('#key').val(); // get email address to be if (keytext.length == 0) { $('#validationresult').html("<span class='errorms return; if (emailtext.length == 0) { $('#validationresult').html("<span class='errorms return; $('#validationresult').html("verifying..."); var 27hub = '//api1.27hub.com/api/a/v1?email=' + encodeur ); ); /execute remote request to perform email verification. A $.getjson(27hub, {).done(function (data) { reportresult(data); ).fail(function (jqxhr, textstatus, error) { var err = textstatus + ", " + error; console.log("request failed: " + err); );; /Output result to the 'validationresult' div element/ function reportresult(data) { var status = data['status'].tolowercase(); // get 'status' from R var additionalstatus = data['additionalstatus']; // get 'addition var message = data['message']; // if there is an error (e.g. lice console.log(status); console.log(additionalstatus); console.log(message); var statushtml; // if there is an error message, show here if (message!= null && message!= '') { statushtml = "<span class='errormsg'>error. Message='" + else { // map REST response data to presentation messages. switch (status) { case 'ok': statushtml = "<span class='statusok'>emai break; case 'bad': statushtml = "<span class='statusbad'>ema break; default: statushtml = "<span class='statusunknown' break; 11.1. Integration Examples 43
console.log(statushtml); </body> </html> </script> // present the result on screen $('#validationresult').html(statushtml); AngularJS (license key) Note: Demonstrates how to call a RESTful service @ //api1.27hub.com/api/a/v1 using AngularJS with client side only calls. <!DOCTYPE html> <!-- Company: (c) 2016, emailhippo.com (https://www.emailhippo.com) File name: v1_key_acl.html Version: 1.0.20140827.0 Version control: - 1.0.20140827.0 - initial release Date: August 2014 Description: Demonstrates how to call a RESTful service @ //api1.27hub.com/api/a/v1 using AngularJS with client side only calls. This example requires a valid key to work correctly. License: Apache 2.0 (https://www.apache.org/licenses/license-2.0) --> <html lang="en" xmlns="http://www.w3.org/1999/xhtml"> <head> <meta charset="utf-8" /> <title>emailhippo.com : License Key Sample.</title> <style type="text/css">.statusunknown { color: #c1c72c;.statusok { 44 Chapter 11. Integration Examples
color: #009933;.statusBad,.errorMsg { color: #ff0000; input[type='text'],input[type='email'] { width: 300px; p label { display: inline-block; width: 60px; </style> </head> <body> <h1>emailhippo.com : email verification demo using simple key authentication with Angular <h2>about</h2> <p>this example shows how to perform email verification using just client side scripting <h2>how to run this sample</h2> <p>this page can be hosted anywhere (i.e. any web host or platform). The only thing neede <h2>key features</h2> <ul> <li>compatible with all modern browsers</li> <li>uses AngularJS 1.2.23</li> <li>no server side scripting required</li> </ul> <hr /> <h2>try it</h2> <div id="myapp" ng-app="apidemo" ng-controller="apidemocontroller"> <form name="verifyform" novalidate="" ng-submit="doverify()"> <p> <label for="key">key:</label> <input type="text" id="key" name="key" tabindex="1" maxlength="20 <span class="errormsg" ng-show="verifyform.key.$error.required"> </p> <p> <label for="email">email:</label> <input type="email" name="email" id="email" tabindex="2" ng-model <span class="errormsg" ng-show="verifyform.email.$error.required" <span class="errormsg" ng-show="verifyform.email.$error.email">no </p> <p> <label> </label> <input type="submit" name="submit" id="submit" tabindex="3" value </p> </form> <div id="validationresult"><!--result output here--> <div ng-show="showvalidating">verifying..</div> <div ng-show="showok"><span class="statusok">email address is ok.</span>< <div ng-show="showbad"><span class="statusbad">email address is not valid <div ng-show="showunknown"><span class="statusunknown">unable to validate <div ng-show="showmessage"><span class="errormsg">error. Message={{errorM </div> </div> <script src="//ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script> 11.1. Integration Examples 45
<script> // Module var app = angular.module('apidemo', []); // Controller app.controller('apidemocontroller', function apidemocontroller($scope,$http) { $scope.query = { key: "", email: "" ; $scope.result = { status: "", additionalstatus: "" ; // verification event $scope.doverify = function () { resetmessage(); $scope.showvalidating = true; var emailverifyapi = '//api1.27hub.com/api/a/v1?email=' + encodeu console.log(emailverifyapi); $http.get(emailverifyapi).success(function (response) { resetmessage(); var status = response['status'].tolowercase(); var additionalstatus = response['additionalstatus var message = response['message']; console.log(status); console.log(additionalstatus); console.log(message); // if there is an error message, show here if (message!= null && message!= '') { $scope.errormessage = message; $scope.showmessage = true; else { // map REST response data to presentation switch (status) { case 'ok': $scope.showok = true; break; case 'bad': $scope.showbad = true; break; default: $scope.additionalstatusme $scope.showunknown = true ); break; 46 Chapter 11. Integration Examples
); // function resetmessage() { $scope.showvalidating = false; $scope.showbad = false; $scope.showmessage = false; $scope.showok = false; $scope.showunknown = false; $scope.showmessage = false; </script> </body> </html> CURL Company: 2016, emailhippo.com (https://www.emailhippo.com) File name: curl.txt Version: 1.0.20140828.0 Version control: - 1.0.20140828.0 - initial release Date: August 2014 Description: Demonstrates how to call a RESTful service @ //api1.27hub.com/api/a/v1 using curl This example requires a valid key to work correctly. License: Apache 2.0 (https://www.apache.org/licenses/license-2.0) curl -i -H "Accept: application/json" "http://api1.27hub.com/api/a/v1?email=email_address&key=your_ap 11.1. Integration Examples 47
48 Chapter 11. Integration Examples
CHAPTER 12 Glossary 12.1 Glossary ACL Access Control List. An ACL is checked against the domain calling the API. ACL authentication does not require a license key and is best in situations where the API is being called from client side script such as JavaScript, jquery, Angular etc. API Application Programmers Interface. See Wikipedia - API Definition for more information. B2B Business To(2) Business Business email hosting services are generally private, enterprise grade hosting services typically hosted in either private data centers or in cloud based infrastructure such. Business to business refers to the activity of businesses sending email to clients using business email addresses. B2C Business To(2) Consumer Consumer email hosting providers are generally well known, mostly web based providers such as Hotmail, Yahoo, AOL, Gmail etc. Business to consumer refers to the activity of businesses sending email to clients using consumer email addresses. Verifying email addresses in consumer domains is generally more technically challenging than B2B Block List See DNSBL. CORS Cross Origin Resource Scripting Allows modern browsers to work with script (e.g. JavaScript) and JSON data originating form other domains. CORS is required to allow client script such a JavaScript, jquery or AngularJS to work with results returned from an external RESTful API. See Wikipedia - CORS for more information. DDoS Distributed Denial of Service See Wikipedia - Denial-of-service attack for more information. DEA Disposable Email Address There are many services available that permit users to use a one-time only email address. Typically, these email addresses are used by individuals wishing to gain access to content or services requiring registration of email addresses but same individuals not wishing to divulge their true identities (e.g. permanent email addresses). 49
DEA addresses should not be regarded as valid for email send purposes as it is unlikely that messages sent to DEA addresses will ever be read. DEA addresses should not be regarded as valid for email send purposes as it is unlikely that messages sent to DEA addresses will ever be read. DNS Domain Name System At its simplest level, DNS converts text based queries (e.g. a domain name) into IP addresses. DNS is also responsible for providing the MX records needed to locate a domains mail servers. See Wikipedia - Domain Name System for more information. DNSBL DNS Block List As an anti-spam measure, mail servers can use spam black lists to look up the reputation of IP addresses and domains sending email. If an IP or domain is on a block list, the mail server may reject the senders email message. See Wikipedia - DNSBL for more information. ESP Email Service Provider A service that sends emails on your behalf. See Wikipedia - Email service provider (marketing) for more information. Grey Listing A technique used in mail servers as an anti-spam technique. Sometimes also known as deferred, grey listing arbitrarily delays the delivery of emails with a try again later response to the client sending the email. See Wikipedia - Grey Listing for more information. HTTP Hypertext Transfer Protocol See Wikipedia - Hypertext Transfer Protocol for more information. JSON JavaScript Object Notation JavaScript Object Notation, is an open standard format that uses human readable text to transmit data objects consisting of attribute value pairs. It is used primarily to transmit data between a server and web application, as an efficient, modern alternative to XML. See Wikipedia - JSON for more information. License Key License key authentication is best for situations where simplicity is required and you can keep the key private. An ideal use case for key authentication would be for server based applications calling the RESTful API. MX Click here to request a license key. Mail Exchanger The MX is a server responsible for email interchange with a client. Office 365 Office 365 mail servers (e.g. x-com.mail.protection.outlook.com) are always configured with the catch all policy, accepting all emails sent to the domain and redirecting them to a central email box for manual inspection. Catch all configured servers cannot respond to requests for email address verification. This does not affect our coverage of Hotmail, Live and Outlook mail boxes. Punycode Punycode is a way to represent Unicode with the limited character subset of ASCII supported by the Domain Name System. See Wikipedia - Punycode for more information. RESTful Representational state transfer See Wikipedia - RESTful for further information. 50 Chapter 12. Glossary
SMTP Simple Mail Transport Protocol SMTP is a protocol. It is the sequence of commands and responses between a client (the software sending an email) and server (the software receiving an email) that facilitates the sending and receiving of email between computer based email messaging systems. Spam Trap Spam traps are email addresses used for the sole purpose of detecting spamming activities. Spam traps are used by many block lists (DNSBL) to detect spammers. For more information, see Wikipedia - Spam Traps. 12.1. Glossary 51
52 Chapter 12. Glossary
Index A ACL, 49 API, 49 B B2B, 49 B2C, 49 Block List, 49 C CORS, 49 D DDoS, 49 DEA, 49 DNS, 50 DNSBL, 50 E ESP, 50 G Grey Listing, 50 H HTTP, 50 J JSON, 50 L License Key, 50 M MX, 50 O Office 365, 50 P Punycode, 50 R RESTful, 50 S SMTP, 51 Spam Trap, 51 53