Create public/private key pair using OAuth RSA-SHA1 method on Windows with OpenSSL

Download OpenSSL from http://slproweb.com/products/Win32OpenSSL.html
And install on your machine.

Or you can download light version from windows 32 bit from here.
Or you can download light version from windows 64 bit from here.

Open Command Prompt as Administrator and navigate to "C:\OpenSSL-Win32\bin". (Assumed that in that location your openssl installed)

Now execute the following three commands:

openssl genrsa -out privatekey.pem 1024

set OPENSSL_CONF=C:/OpenSSL-Win32/bin/openssl.cfg [It may  be .cfg or .cnf, check your bin directory]

openssl req -new -x509 -key privatekey.pem -out publickey.cer -days 1825

Below are two screen-shots:

Send Email Using Google OAuth & Java

Download source code & required jars from here

For get access token & google user id click here

package com.pkm.google_auth;

import com.google.api.client.googleapis.GoogleUtils;
import com.google.api.client.googleapis.auth.oauth2.GoogleCredential;
import com.google.api.client.http.HttpTransport;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.JsonFactory;
import com.google.api.client.json.jackson2.JacksonFactory;
import com.google.api.client.repackaged.org.apache.commons.codec.binary.Base64;
import com.google.api.services.gmail.Gmail;
import com.google.api.services.gmail.model.MessagePartHeader;

import javax.mail.BodyPart;
import javax.mail.Message;
import javax.mail.Multipart;
import javax.mail.Session;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;
import java.io.ByteArrayOutputStream;
import java.util.Properties;

/**
 * Created by pritom on 18/12/2016.
 */
public class SendMail {
    private static final String USER_ID = "118224585672607576118";
    private static final String ACCESS_TOKEN = "ya29.Ci-4A700L53csid7qv6786780mbRqI8hdwesj7H2RSRnBizwfWFUY0pzYsx_xa-XZA";

    public static void main(String[] args) throws Exception {
        sendMail();
    }

    private static void sendMail() throws Exception {
        Properties props = new Properties();
        Session mailSession = Session.getInstance(props, new javax.mail.Authenticator() {

        });
        MimeMessage message = new MimeMessage(mailSession);

        message.setSubject("Test subject", "UTF-8");
        message.addRecipient(Message.RecipientType.TO, new InternetAddress("pritom@xxxxx.com", "Pritom Kumar"));

        Multipart multipart = new MimeMultipart();
        BodyPart messageBodyPart = new MimeBodyPart();
        messageBodyPart.setContent("<DIV><B>BOLD HTML BODY</B></DIV>", "text/html");
        multipart.addBodyPart(messageBodyPart);

        message.addHeader("CUSTOM_HEADER_1", "CUSTOM_HEADER_1_VALUE");
        message.addHeader("CUSTOM_HEADER_2", "CUSTOM_HEADER_2_VALUE");

        message.setContent(multipart );

        GoogleCredential credential = new GoogleCredential().setAccessToken(ACCESS_TOKEN);
        Gmail gmail = new Gmail.Builder(_createHttpTransport(), _createJsonFactory(), credential).build();

        com.google.api.services.gmail.model.Message email = createMessageWithEmail(message);
        email = gmail.users().messages().send(USER_ID, email).execute();
        String emailID = email.getId(), messageID = getUniqueMessageIDByEMailId(emailID);
        System.out.println("EMAIL_SEND_WITH_GOOGLE_MAIL_ID=" + emailID);
        System.out.println("EMAIL_SEND_WITH_UNIQUE_MAIL_ID=" + messageID);
    }

    private static String getUniqueMessageIDByEMailId(String emailID) throws Exception {
        GoogleCredential credential = new GoogleCredential().setAccessToken(ACCESS_TOKEN);
        Gmail gmail = new Gmail.Builder(_createHttpTransport(), _createJsonFactory(), credential).build();
        com.google.api.services.gmail.model.Message message = gmail.users().messages().get(USER_ID, emailID).execute();
        for (MessagePartHeader messagePartHeader : message.getPayload().getHeaders()) {
            if (messagePartHeader.getName().equalsIgnoreCase("Message-ID")) {
                emailID = messagePartHeader.getValue().substring(1, messagePartHeader.getValue().length() - 1);
            }
        }
        return emailID;
    }

    private static com.google.api.services.gmail.model.Message createMessageWithEmail(MimeMessage email) throws Exception {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        email.writeTo(baos);
        String encodedEmail = Base64.encodeBase64URLSafeString(baos.toByteArray());
        com.google.api.services.gmail.model.Message message = new com.google.api.services.gmail.model.Message();
        message.setRaw(encodedEmail);
        return message;
    }

    private static HttpTransport _createHttpTransport() throws Exception {
        return new NetHttpTransport.Builder()
                .trustCertificates(GoogleUtils.getCertificateTrustStore())
                .build();
    }

    private static JsonFactory _createJsonFactory() {
        return new JacksonFactory();
    }
}

Write a PHP app to get/read Outlook Office 365 mail using oauth connection

1. Go to https://apps.dev.microsoft.com/#/appList
2. Click on "Add an app"
3. Put a name on "New Application Registration" form such "My App"
4. And click "Create application" button
5. It will redirect to you your application page:
https://apps.dev.microsoft.com/#/application/da8a54d8-86b5-4196-981e-XXXXXXXXXX
6. Find the button "Generate New Password" and click
7. Copy the password: "pYJAiGeYTXXXXXXXvzhfp"
8. Find "Platforms" button and click "Add platform" and select "Web"
9. Enter your application url in the field "Redirect URIs" 
http://localhost/tappi/office.php (Your uri would be different)
10. And click on "Save" button
11. Done from this end.

Api reference: https://dev.outlook.com/restapi/reference

Now follow the php code snippet (full example to get user profile, read email & send email):

<?php
session_start();
init();

if(token()) {
    echo "<a href='".$_SESSION["redirect_uri"]."''>Home</a>";
    echo " || <a href='".$_SESSION["redirect_uri"]."?refresh_token=true'>Refresh token</a>";
    echo " || <a href='".$_SESSION["redirect_uri"]."?profile=true'>Profile</a>";
    echo " || <a href='".$_SESSION["redirect_uri"]."?list_email=true'>List Email</a>";
    echo " || <a href='".$_SESSION["redirect_uri"]."?logout=true'>Logout</a><br/><br/>\n\n";
}

if(isset($_GET["logout"])) {
    flush_token();
    echo "Logged out<br/>";
    echo "<a href='".$_SESSION["redirect_uri"]."'>Start new session</a>";
    die();
}
else if(isset($_GET["profile"])) {
    view_profile();
}
else if(isset($_GET["refresh_token"])) {
    refresh_token();
}
else if(isset($_GET["list_email"])) {
    list_email();
}
else if(isset($_GET["view_email"])) {
    view_email();
}
else if(isset($_GET["view_attachments"])) {
    view_attachments();
}
else if(token()) {
    echo "<pre>"; print_r(token()); echo "</pre>";
}
elseif (isset($_GET["code"])) {
    echo "<pre>";print_r($_GET);echo "</pre>";
    $token_request_data = array (
        "grant_type" => "authorization_code",
        "code" => $_GET["code"],
        "redirect_uri" => $_SESSION["redirect_uri"],
        "scope" => implode(" ", $_SESSION["scopes"]),
        "client_id" => $_SESSION["client_id"],
        "client_secret" => $_SESSION["client_secret"]
    );
    $body = http_build_query($token_request_data);
    $response = runCurl($_SESSION["authority"].$_SESSION["token_url"], $body);
    $response = json_decode($response);

    store_token($response);
    file_put_contents("office_active_user_id.txt", get_user_id());
    file_put_contents("office_access_token.txt", $response->access_token);
    header("Location: " . $_SESSION["redirect_uri"]);
}
else {
    $accessUrl = $_SESSION["authority"].$_SESSION["auth_url"];
    echo "<a href='$accessUrl'>Login with Office 365</a>";
}

function view_email() {
    $mailID = $_GET["view_email"];
    $userID = get_user_id();
    $headers = array(
        "User-Agent: php-tutorial/1.0",
        "Authorization: Bearer ".token()->access_token,
        "Accept: application/json",
        "client-request-id: ".makeGuid(),
        "return-client-request-id: true",
        "X-AnchorMailbox: ". get_user_email()
    );
    $outlookApiUrl = $_SESSION["api_url"] . "/Users('$userID')/Messages('$mailID')";
    $response = runCurl($outlookApiUrl, null, $headers);
    $response = explode("\n", trim($response));
    $response = $response[count($response) - 1];
    $response = json_decode($response, true);
    echo "<pre>"; print_r($response); echo "</pre>";
}

function view_attachments() {
    $mailID = $_GET["view_attachments"];
    $folder = "Office-" . md5($mailID);
    if(!file_exists($folder)) {
        mkdir($folder);
    }
    $userID = get_user_id();
    $headers = array(
        "User-Agent: php-tutorial/1.0",
        "Authorization: Bearer ".token()->access_token,
        "Accept: application/json",
        "client-request-id: ".makeGuid(),
        "return-client-request-id: true",
        "X-AnchorMailbox: ". get_user_email()
    );
    $outlookApiUrl = $_SESSION["api_url"] . "/Users('$userID')/Messages('$mailID')/Attachments";
    $response = runCurl($outlookApiUrl, null, $headers);
    $response = explode("\n", trim($response));
    $response = $response[count($response) - 1];
    $response = json_decode($response, true);
    $file_links = "";
    foreach ($response["value"] as $attachment) {
        $to_file = $folder . "/" . md5($attachment["ContentId"]) . "-" . $attachment["Name"];
        file_put_contents($to_file, base64_decode($attachment["ContentBytes"]));
        if($file_links != "") {
            $file_links = $file_links . " ||| ";
        }
        $file_links .= "<a href='$to_file' target='_blank'>" . $attachment["Name"] . "</a>";
    }
    echo $file_links . "<br/><br/>";
    echo "<pre>"; print_r($response); echo "</pre>";
}

function list_email() {
    $headers = array(
        "User-Agent: php-tutorial/1.0",
        "Authorization: Bearer ".token()->access_token,
        "Accept: application/json",
        "client-request-id: ".makeGuid(),
        "return-client-request-id: true",
        "X-AnchorMailbox: ". get_user_email()
    );
    $top = 2;
    $skip = isset($_GET["skip"]) ? intval($_GET["skip"]) : 0;
    $search = array (
        // Only return selected fields
        "\$select" => "Subject,ReceivedDateTime,Sender,From,ToRecipients,HasAttachments,BodyPreview",
        // Sort by ReceivedDateTime, newest first
        "\$orderby" => "ReceivedDateTime DESC",
        // Return at most n results
        "\$top" => $top, "\$skip" => $skip
    );
    $outlookApiUrl = $_SESSION["api_url"] . "/Me/MailFolders/Inbox/Messages?" . http_build_query($search);
    $response = runCurl($outlookApiUrl, null, $headers);
    $response = explode("\n", trim($response));
    $response = $response[count($response) - 1];
    $response = json_decode($response, true);
    //echo "<pre>"; print_r($response); echo "</pre>";
    if(isset($response["value"]) && count($response["value"]) > 0) {
        echo "<style type='text/css'>td{border: 2px solid #cccccc;padding: 30px;text-align: center;vertical-align: top;}</style>";
        echo "<table style='width: 100%;'><tr><th>From</th><th>Subject</th><th>Preview</th></tr>";
        foreach ($response["value"] as $mail) {
            $BodyPreview = str_replace("\n", "<br/>", $mail["BodyPreview"]);
            echo "<tr>";
            echo "<td>".$mail["From"]["EmailAddress"]["Address"].
                "<br/><a target='_blank' href='?view_email=".$mail["Id"]."'>View Email</a>";
            if($mail["HasAttachments"] == 1) {
                echo "<br/><a target='_blank' href='?view_attachments=".$mail["Id"]."'>View Attachments</a>";
            }
            echo "</td><td>".$mail["Subject"]."</td>";
            echo "<td>".$BodyPreview."</td>";
            echo "</tr>";
        }
        echo "</table>";
    }
    else {
        echo "<div><h3><i>No email found</i></h3></div>";
    }
    $prevLink = "";
    if($skip > 0) {
        $prev = $skip - $top;
        $prevLink = "<a href='?list_email=true&skip=".$prev."'>Previous Page</a>";
    }
    if(isset($response["@odata.nextLink"])) {
        if($prevLink != "") {
            $prevLink .= " ||| ";
        }
        echo "<br/>".$prevLink."<a href='?list_email=true&skip=".($skip + $top)."'>Next Page</a>";
    }
    else {
        echo "<br/>" . $prevLink;
    }
}

function refresh_token() {
    $token_request_data = array (
        "grant_type" => "refresh_token",
        "refresh_token" => token()->refresh_token,
        "redirect_uri" => $_SESSION["redirect_uri"],
        "scope" => implode(" ", $_SESSION["scopes"]),
        "client_id" => $_SESSION["client_id"],
        "client_secret" => $_SESSION["client_secret"]
    );
    $body = http_build_query($token_request_data);
    $response = runCurl($_SESSION["authority"].$_SESSION["token_url"], $body);
    $response = json_decode($response);
    store_token($response);
    file_put_contents("office_access_token.txt", $response->access_token);
    header("Location: " . $_SESSION["redirect_uri"]);
}

function get_user_id() {
    if(isset($_SESSION["user_id"]) && strlen($_SESSION["user_id"]) > 0) {
        return $_SESSION["user_id"];
    }
    view_profile(true);
    $response = json_decode(file_get_contents("office_user_data.txt"));
    $_SESSION["user_id"] = $response->Id;
    return $response->Id;
}

function get_user_email() {
    if(isset($_SESSION["user_email"]) && strlen($_SESSION["user_email"]) > 0) {
        return $_SESSION["user_email"];
    }
    view_profile(true);
    $response = json_decode(file_get_contents("office_user_data.txt"));
    $_SESSION["user_email"] = $response->EmailAddress;
    return $response->EmailAddress;
}

function view_profile($skipPrint = false) {
    $headers = array(
        "User-Agent: php-tutorial/1.0",
        "Authorization: Bearer ".token()->access_token,
        "Accept: application/json",
        "client-request-id: ".makeGuid(),
        "return-client-request-id: true"
    );
    $outlookApiUrl = $_SESSION["api_url"] . "/Me";
    $response = runCurl($outlookApiUrl, null, $headers);
    $response = explode("\n", trim($response));
    $response = $response[count($response) - 1];
    file_put_contents("office_user_data.txt", $response);
    $response = json_decode($response);
    $_SESSION["user_id"] = $response->Id;
    $_SESSION["mail_id"] = $response->MailboxGuid;
    $_SESSION["user_email"] = $response->EmailAddress;
    if(!$skipPrint) {
        echo "<pre>"; print_r($response); echo "</pre>";
    }
}

function makeGuid(){
    if (function_exists('com_create_guid')) {
        error_log("Using 'com_create_guid'.");
        return strtolower(trim(com_create_guid(), '{}'));
    }
    else {
        $charid = strtolower(md5(uniqid(rand(), true)));
        $hyphen = chr(45);
        $uuid = substr($charid, 0, 8).$hyphen
            .substr($charid, 8, 4).$hyphen
            .substr($charid, 12, 4).$hyphen
            .substr($charid, 16, 4).$hyphen
            .substr($charid, 20, 12);
        return $uuid;
    }
}

function flush_token() {
    file_put_contents("office_auth_config.txt", "");
    $_SESSION["user_id"] = "";
    $_SESSION["mail_id"] = "";
}

function store_token($o) {
    file_put_contents("office_auth_config.txt", json_encode($o));
}

function token() {
    $text = file_exists("office_auth_config.txt") ? file_get_contents("office_auth_config.txt") : null;
    if($text != null && strlen($text) > 0) {
        return json_decode($text);
    }
    return null;
}

function init() {
    $_SESSION["client_id"] = "da8a54d8-86b5-xxxx-xxxx-e31efa3f3d59";
    $_SESSION["client_secret"] = "pYJAxxxxxxxxxxxxxxxX3vzhfp";
    $_SESSION["redirect_uri"] = "http://localhost/tappi/office.php";
    $_SESSION["authority"] = "https://login.microsoftonline.com";
    $_SESSION["scopes"] = array("offline_access", "openid");
    /* If you need to read email, then need to add following scope */
    if(true) {
        array_push($_SESSION["scopes"], "https://outlook.office.com/mail.read");
    }
    /* If you need to send email, then need to add following scope */
    if(true) {
        array_push($_SESSION["scopes"], "https://outlook.office.com/mail.send");
    }

    $_SESSION["auth_url"] = "/common/oauth2/v2.0/authorize";
    $_SESSION["auth_url"] .= "?client_id=".$_SESSION["client_id"];
    $_SESSION["auth_url"] .= "&redirect_uri=".$_SESSION["redirect_uri"];
    $_SESSION["auth_url"] .= "&response_type=code&scope=".implode(" ", $_SESSION["scopes"]);

    $_SESSION["token_url"] = "/common/oauth2/v2.0/token";

    $_SESSION["api_url"] = "https://outlook.office.com/api/v2.0";
}

function runCurl($url, $post = null, $headers = null) {
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_POST, $post == null ? 0 : 1);
    if($post != null) {
        curl_setopt($ch, CURLOPT_POSTFIELDS, $post);
    }
    curl_setopt($ch, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    if($headers != null) {
        curl_setopt($ch, CURLOPT_HEADER, true);
        curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
    }
    $response = curl_exec($ch);
    $http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    curl_close($ch);
    if($http_code >= 400) {
        echo "Error executing request to Office365 api with error code=$http_code<br/><br/>\n\n";
        echo "<pre>"; print_r($response); echo "</pre>";
        die();
    }
    return $response;
}
?>

Not receiving Google OAuth refresh token

The refresh_token is only provided on the first authorization from the user. Subsequent authorizations, such as the kind you make while testing an OAuth2 integration, will not return the refresh_token again.

Go to your account security settings: 
https://security.google.com/settings/security/permissions?pli=1.

Then click "Revoke Access" next to your app.
The next OAuth2 request you make will return a refresh_token.

You need "access_type=offline" & "approval_prompt=force" in all cases when you want the refresh_token.

Php & MySql oAuth Server & Client Example

Server side common.php (Need to include in all server side scripts)

<?php
require_once 'oauthLibrary/OAuthServer.php';
session_start();
 
// Add a header indicating this is an OAuth server
header('X-XRDS-Location: http://' . $_SERVER['SERVER_NAME'] . '/services.xrds.php');
 
// Connect to database
$db = new PDO('mysql:host=localhost;dbname=oauthdb', 'root', '');
 
// Create a new instance of OAuthStore and OAuthServer
$store = OAuthStore::instance('PDO', array('conn' => $db));
$server = new OAuthServer();
OAuthRequestLogger::enableLogging($store);
?>

Client side common.php (Need to include in all client side scripts)

<?php
session_start();

define("PATH_URL_CLIENT", "/oauth/client");
define("PATH_URL_SERVER", "/oauth/server");

define("REQUEST_TOKEN", "REQUEST_TOKENsdsdfw324ft3f3f34r34");
define("ACCESS_TOKEN", "ACCESS_TOKENkdfj33jdl23");
define("OAUTH_TOKEN", "OAUTH_TOKENdfs34fre45u67jyu");
define("OAUTH_VERIFIER", "OAUTH_VERIFIERslsjlf32j3jlfj");


require './lib/OAuthClient.php';
$client = new OAuthClient('8179e89ff6558cce5628e60643a7124c053cfc204', 'f46dfa522890df25e71ccd9db463a708');

function getServerUrl() {
    return "http://".$_SERVER["HTTP_HOST"].PATH_URL_SERVER;
}

function getClientUrl() {
    return "http://".$_SERVER["HTTP_HOST"].PATH_URL_CLIENT;
}

function toSession($key, $value) {
    $_SESSION[$key] = is_null($value) ? $value : serialize($value);
}

function fromSession($key) {
    if(isset($_SESSION[$key]) && !is_null($_SESSION[$key])) {
        return unserialize($_SESSION[$key]);
    }
    return null;
}
?>

1. Browse http://localhost/oauth/server/registration.html and fill up all fields.

2. You will be view the following information which will need to communication to server.

3. Browse the following url to get the token url, copy the url and browse

4. If you logged in success in server url, you will redirect to your callback url you specified when registration with token & verifier.

5. You are now ready to request data from server.

Download full code example.