added DB functions

content/php/confirm.php

@@ -1,31 +1,56 @@
 <?php
 // inspired by https://www.mailgun.com/blog/email/double-opt-in-with-php-mailgun/
-$statusCode = 'HTTP/1.1 303 See Other';
+
+require(dirname(__FILE__) . '/settings.php');
+
 $successURL = '/newsletter/confirmed.html';
 $errorURL = '/newsletter/confirm-error.html';
 
-// return TRUE when successful, message string on failure
-// e.g. Adresse schon vorhanden, Datenbank-Fehler, was noch?
-function AddSubscriberToDB($recipientAddress) {
-  global $db;
-  echo 'ah jup';
+// Adds new subscriber to database. Returns an error message on failure, TRUE on success.
+function AddSubscriberToDB($subscriberAddress, $subscriberName = NULL) {
+  global $general;
+  
+  try {
+    $pdo = getPDO();
+    
+    // create table if it doesn't exist already
+    $query = $pdo->prepare($general['sql']['create_table']);
+    if ( ! $query->execute() ) {
+      error_log('Datenbankfehler beim Prüfen/Erzeugen der Tabelle.');
+      return "Ein Fehler ist aufgetreten.";
+    }
+    
+    // check if record exists
+    $query = $pdo->prepare($general['sql']['read_record']);
+    if ( ! $query->execute([':e' => $subscriberAddress]) ) {
+      error_log("Datenbankfehler: Adresscheck für Emailadresse {$subscriberAddress} ergab einen Fehler.");       
+      return 'Datenbankfehler.';
+    }
+    if ( $query->fetch() ) {
+      error_log("Datenbankfehler: Emailadresse {$subscriberAddress} ist bereits eingetragen.");
+      return "Emailadresse ist bereits eingetragen.";
+    }
+
+    // create record 
+    $query = $pdo->prepare($general['sql']['create_record']);
+    if ( ( ! $query->execute([':e' => $subscriberAddress, ':n' => $subscriberName]) ) or ( $query->fetch() ) ) {
+      error_log("Datenbankfehler: Einfügen von Emailadresse {$subscriberAddress} ergab einen Fehler.");       
+      return 'Datenbankfehler.';
+    }
+  } catch(\PDOException $e) {
+    error_log("Datenbankfehler: {$e->getMessage()}");
+    return $e->getMessage();
+  }
   return TRUE;
 }
 
-function CheckConfirmationHash($confEmail, $confCode) {
-  global $general;
-  return (md5($confEmail . $general['uniqueKey']) === $confCode);
-}
-
-require(dirname(__FILE__) . '/settings.php');
-
 if (isset($_GET['c']) && isset($_GET['e'])) {
   $c = filter_var($_GET['c'], FILTER_SANITIZE_STRING);
   $e = filter_var($_GET['e'], FILTER_SANITIZE_STRING);
 
-  if (CheckConfirmationHash($e, $c)) {
+  if ( GetConfirmationHash($e) === $c ) {
     $result = AddSubscriberToDB($e);
-    if ($result == TRUE) {
+    if ($result === TRUE) {
       GracefulExit($successURL, 'Bestätigung erfolgt: Newsletter-Anmeldung bestätigt');
     } elseif (gettype($result == 'string')) {
       GracefulExit($errorURL, "Bestätigung fehlgeschlagen: {$result}");

content/php/settings.php

@@ -11,16 +11,28 @@ require $dname . '/SMTP.php';
 
 // general constants
 $general = [
-//  'domain' => 'tobias-radloff.de',
+  // site domain (used for building confirmation links)
+/*  'domain' => 'tobias-radloff.de', */
   'domain' => 'localhost',
+  // string concatenated with email address to create a non-recreatable md5 hash 
   'uniqueKey' => '***REMOVED***', // works like password salt  
+  // file name of confirm script
   'confirmScript' => '/confirm.php',
-  'statusCode' => 'HTTP/1.1 303 See Other'
+  // status code to be used when redirection to success or error page 
+  'statusCode' => 'HTTP/1.1 303 See Other',
+  // array of SQL statements used
+  'sql' => [
+    'create_table' => 'CREATE TABLE IF NOT EXISTS subscribers (id INTEGER PRIMARY KEY, email TEXT NOT NULL UNIQUE, name TEXT);',
+    'create_record' => 'INSERT INTO subscribers(email, name) VALUES(:e, :n);',
+    'read_record' => 'SELECT 1 FROM subscribers WHERE email = :e;',
+    'update_record' => '',
+    'delete_record' => 'DELETE FROM subscribers WHERE email = :e;'
+  ]
 ]; 
-
+// complete site URL
 $general['siteURL'] = 'https://' . $general['domain']; 
 
-// smtp info
+// SMTP server information
 $smtp = [
   'host' => '***REMOVED***
   'port' => 587,
@@ -31,28 +43,47 @@ $smtp = [
   'fromName' => 'Tobias Radloffs Newsletter',
 ];
 
+// body of confirmation email
 $bodyConfirmation = [
   'Hallo!',
   'Bitte bestätige die Anmeldung für meinen Newsletter, indem du auf den folgenden Link klickst:',
-  '%Placeholder%',  // placeholder 
+  '%Placeholder%', 
   'Bis bald und viele Grüße, Tobias' 
 ];
 
-// mail contents
+// contents of confirmation email
 $mailConfirmation = [
   'subject' => 'Newsletter-Anmeldung bestaetigen',
   'bodyHTML' => '<p>' . implode('</p><p>', $bodyConfirmation) . '</p>',
   'bodyText' => implode("\n\n", $bodyConfirmation)
 ];
 
-// DB constants
+// database information
 $db = [
+  'sqlite' => [
+    'dsn' => 'sqlite:../newsletter.sqlite',
+  ],
+  'mysql' => [
+    'dsn' => '',
     'host' => '',
     'port' => '',
     'username' => '',
     'password' => ''
+  ]
 ];
 
+function GetConfirmationHash($confEmail) {
+  global $general;
+  return md5($confEmail . $general['uniqueKey'] );
+}
+
+// connects to database and returns PDO object
+function getPDO($dbType = 'sqlite') {
+  global $db;
+  return new \PDO($db[$dbType]['dsn']);
+}
+
+// Sends an email to single recipient with subject and body specified in an array. Returns an error message on failure, TRUE on success.
 function SendEmail($recipientAddress, $mailContents, $link = NULL) {
   global $general, $smtp;
 
@@ -92,6 +123,7 @@ function SendEmail($recipientAddress, $mailContents, $link = NULL) {
   }
 }
 
+// redirects to specified URL via GET request and conveys an optional message  
 function GracefulExit($location, $message = NULL) {
   global $general;
   header($general['statusCode']);

content/php/subscribe.php

@@ -6,20 +6,15 @@ $errorURL = '/newsletter/subscribe-error.html';
 
 require(dirname(__FILE__) . '/settings.php');
 
-function MakeConfirmationHash($confEmail, $confCode) {
-  return md5($confEmail . $confCode);
-}
-
 if (isset($_POST['email'])) {
   $email = filter_var(trim($_POST['email'], FILTER_SANITIZE_STRING));
-error_log("Email ist: {$email}");
+
   if (filter_var($email, FILTER_VALIDATE_EMAIL)) { 
-    $hashedUnique = MakeConfirmationHash($email, $general['uniqueKey']);
-    $confirmQuery = http_build_query(['c' => $hashedUnique, 'e' => $email]);
+    $confirmQuery = http_build_query(['c' => GetConfirmationHash($email), 'e' => $email]);
     $confirmLink = $general['siteURL'] . $general['confirmScript'] . "?" . $confirmQuery;
     
     $result = SendEmail($email, $mailConfirmation, $confirmLink);
-    if ( $result == TRUE ) {
+    if ( $result === TRUE ) {
       GracefulExit($successURL, 'Anmeldung wird fortgesetzt: Email mit Bestätigungslink wurde versandt.');
     } else {
       GracefulExit($errorURL, 'Anmeldung fehlgeschlagen: Fehler beim Versenden der Bestätigungs-Email.');

content/php/unsubscribe.php

@@ -7,14 +7,39 @@ $errorURL = '/newsletter/unsubscribe-error.html';
 
 
 function RemoveSubscriberFromDB($subscriberAddress) {
-  error_log("removing subscriber {$subscriberAddress} from DB ...");
+  global $general;
+
+  try {
+    $pdo = getPDO();
+
+    // make sure record exists
+    $query = $pdo->prepare($general['sql']['read_record']);
+    if ( ! $query->execute([':e' => $subscriberAddress]) ) {
+      error_log("Datenbankfehler: Adresscheck für {$subscriberAddress} ergab einen Fehler.");       
+      return 'Datenbankfehler.';
+    }
+    if ( ! $query->fetch() ) {
+      error_log("Datenbankfehler: Emailadresse {$subscriberAddress} nicht in Datenbank vorhanden.");
+      return "Emailadresse nicht bekannt.";
+    }
+
+    // delete record 
+    $query = $pdo->prepare($general['sql']['delete_record']);
+    if ( ! $query->execute([':e' => $subscriberAddress])) {
+      error_log("Datenbankfehler: Löschen von Emailadresse {$subscriberAddress} ergab einen Fehler.");       
+      return 'Fehler beim Löschen des Datenbankeintrags.';
+    }
+  } catch(\PDOException $e) {
+    error_log("Datenbankfehler: {$e->getMessage()}");
+    return $e->getMessage();
+  }
   return TRUE;
 }
 
 if (isset($_GET['e'])) {
   $e = filter_var($_GET["e"], FILTER_SANITIZE_STRING);
   $result = RemoveSubscriberFromDB($e);
-  if ($result == TRUE) {
+  if ($result === TRUE) {
     GracefulExit($successURL, "Abmeldung für {$e} erfolgreich.");
   } elseif (gettype($result == 'string')) {
     GracefulExit($errorURL, "Abmeldung fehlgeschlagen: {$result}");