Merge pull request #13 from B00tLoad/4-save-and-retrieve-auth-tokens

4 Save and retrieve auth tokens

src/main/java/de/b00tload/tools/lastfmtospotifyplaylist/LastFMToSpotify.java

@@ -29,6 +29,7 @@ import static de.b00tload.tools.lastfmtospotifyplaylist.util.Logger.logLn;
 public class LastFMToSpotify {
 
     public static final String LINE_SEPERATOR = System.getProperty("line.separator");
+    public static final String USER_HOME = System.getProperty("user.home");
     public static HashMap<String, String> configuration;
 
     public static void main(String[] args) {
@@ -67,7 +68,6 @@ public class LastFMToSpotify {
             }
         }
 
-
         try {
             logLn("Authenticating with Spotify...", 1);
             SpotifyApi.Builder build = SpotifyApi.builder();
@@ -76,23 +76,33 @@ public class LastFMToSpotify {
             build.setRedirectUri(URI.create("http://localhost:9876/callback/spotify/"));
             SpotifyApi api = build.build();
             AtomicBoolean waiting = new AtomicBoolean(true);
-            try (Javalin webserver = Javalin.create().start(9876)) {
+            if (configuration.containsKey("cache.crypto") && TokenHelper.existsTokens()) {
-                Runtime.getRuntime().addShutdownHook(new Thread(webserver::stop));
+                AuthorizationCodeCredentials oldcred = TokenHelper.fetchTokens();
-                webserver.get("/callback/spotify", ctx -> {
+                AuthorizationCodeCredentials newcred = api.authorizationCodeRefresh(api.getClientId(), api.getClientSecret(), oldcred.getRefreshToken()).build().execute();
-                    if(ctx.queryParamMap().containsKey("code")) {
+                TokenHelper.saveTokens(newcred);
-                        AuthorizationCodeCredentials cred = api.authorizationCode(ctx.queryParam("code")).build().execute();
+                configuration.put("spotify.access", newcred.getAccessToken());
-                        configuration.put("spotify.access", cred.getAccessToken());
+            } else {
-                        if(configuration.containsKey("spotify.saveaccess")) TokenHelper.saveTokens(cred);
+                try (Javalin webserver = Javalin.create().start(9876)) {
-                        ctx.result("success. <script>let win = window.open(null, '_self');win.close();</script>").contentType(ContentType.TEXT_HTML).status(HttpStatus.OK);
+                    Runtime.getRuntime().addShutdownHook(new Thread(webserver::stop));
-                        waiting.set(false);
+//                    webserver.exception(Exception.class, (exception, ctx) -> {
-                    } else {
+//                        ctx.result(exception.getMessage());
-                        logLn("Error: Spotify authorization failed."+LINE_SEPERATOR+ctx.queryParam("error"), 1);
+//                    });
-                        System.exit(500);
+                    webserver.get("/callback/spotify", ctx -> {
-                    }
+                        if(ctx.queryParamMap().containsKey("code")) {
-                });
+                            AuthorizationCodeCredentials cred = api.authorizationCode(ctx.queryParam("code")).build().execute();
-                logLn("Waiting for Spotify authorization.", 1);
+                            configuration.put("spotify.access", cred.getAccessToken());
-                //TODO: Open auth page in Browser
+                            if(configuration.containsKey("cache.crypto")) TokenHelper.saveTokens(cred);
-                while (waiting.get());
+                            ctx.result("success. <script>let win = window.open(null, '_self');win.close();</script>").contentType(ContentType.TEXT_HTML).status(HttpStatus.OK);
+                            waiting.set(false);
+                        } else {
+                            logLn("Error: Spotify authorization failed."+LINE_SEPERATOR+ctx.queryParam("error"), 1);
+                            System.exit(500);
+                        }
+                    });
+                    logLn("Waiting for Spotify authorization.", 1);
+                    //TODO: Open auth page in Browser
+                    while (waiting.get());
+                }
             }
             logLn("Authenticating with LastFM...", 1);
             Caller.getInstance().setApiRootUrl("https://ws.audioscrobbler.com/2.0/");

src/main/java/de/b00tload/tools/lastfmtospotifyplaylist/arguments/ArgumentHandler.java

@@ -41,6 +41,7 @@ public class ArgumentHandler {
             case NAME -> name(value);
             case PUBLIC -> access("public");
             case COLLABORATIVE -> access("collaborative");
+            case SPOTIFY_CACHING -> cache(value);
         }
     }
 
@@ -229,4 +230,12 @@ public class ArgumentHandler {
 
         configuration.put("playlist.name", name);
     }
+
+    public static void cache(String value){
+        if (value == null || value.isEmpty()) {
+            logLn("--spotifycache must be provided with a password. Check usage: " + Arguments.SPOTIFY_CACHING.getUsage(), 1);
+            System.exit(500);
+        }
+        configuration.put("cache.crypto", value);
+    }
 }

src/main/java/de/b00tload/tools/lastfmtospotifyplaylist/arguments/Arguments.java

@@ -41,7 +41,9 @@ public enum Arguments {
     PUBLIC("public", "[Optional] [EXCLUSIVE: public, collaborative]" + LINE_SEPERATOR
                                         + "Makes the playlist public.", "--public", "pP"),
     COLLABORATIVE("collaborative", "[Optional] [EXCLUSIVE: public, collaborative]" + LINE_SEPERATOR
-                                        + "Makes the playlist collaborative.", "--collaborative", "pC");
+                                        + "Makes the playlist collaborative.", "--collaborative", "pC"),
+    SPOTIFY_CACHING("spotifycache", "[Optional]" + LINE_SEPERATOR
+                                        + "Saves and (if possible) retrieves auth tokens from a locally saved file.", "--spotifycache <password>", "sTk");
 
     private final String name;
     private final String description;

src/main/java/de/b00tload/tools/lastfmtospotifyplaylist/util/CryptoHelper.java

@@ -0,0 +1,64 @@
+package de.b00tload.tools.lastfmtospotifyplaylist.util;
+
+
+import javax.crypto.*;
+import javax.crypto.spec.IvParameterSpec;
+import javax.crypto.spec.PBEKeySpec;
+import javax.crypto.spec.SecretKeySpec;
+import java.io.*;
+import java.nio.file.Path;
+import java.security.InvalidAlgorithmParameterException;
+import java.security.InvalidKeyException;
+import java.security.NoSuchAlgorithmException;
+import java.security.spec.InvalidKeySpecException;
+import java.security.spec.KeySpec;
+
+public class CryptoHelper {
+
+    public static SecretKey createKeyFromPassword(String pass){
+        try {
+            KeySpec spec = new PBEKeySpec(pass.toCharArray(), "abcdefghijklmnop".getBytes(), 65536, 256); // AES-256
+            SecretKeyFactory f = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
+            byte[] key = new byte[0];
+            key = f.generateSecret(spec).getEncoded();
+            return new SecretKeySpec(key, "AES");
+        } catch (InvalidKeySpecException | NoSuchAlgorithmException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    public static void serializeEncrypted(Serializable obj, Path file, SecretKey key){
+        try {
+            if(file.toFile().exists()) file.toFile().delete();
+            if(!file.getParent().toFile().exists()) file.getParent().toFile().mkdirs();
+            file.toFile().createNewFile();
+            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
+            IvParameterSpec iv = new IvParameterSpec("abcdefghijklmnop".getBytes());
+            cipher.init(Cipher.ENCRYPT_MODE, key, iv);
+            SealedObject sealedObject = new SealedObject( obj, cipher);
+            CipherOutputStream cipherOutputStream = new CipherOutputStream( new BufferedOutputStream( new FileOutputStream( file.toFile() ) ), cipher );
+            ObjectOutputStream outputStream = new ObjectOutputStream( cipherOutputStream );
+            outputStream.writeObject( sealedObject );
+            outputStream.close();
+        } catch (NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException | IOException | IllegalBlockSizeException | InvalidAlgorithmParameterException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    public static Serializable deserializeEncrypted(Path file, SecretKey key) {
+        Serializable ret = null;
+        try {
+            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
+            IvParameterSpec iv = new IvParameterSpec("abcdefghijklmnop".getBytes());
+            cipher.init(Cipher.DECRYPT_MODE, key, iv);
+            CipherInputStream cipherInputStream = new CipherInputStream( new BufferedInputStream( new FileInputStream( file.toFile() ) ), cipher );
+            ObjectInputStream inputStream = new ObjectInputStream( cipherInputStream );
+            SealedObject sealedObject = (SealedObject) inputStream.readObject();
+            ret = (Serializable) sealedObject.getObject(cipher);
+        } catch (NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException | IOException | IllegalBlockSizeException | ClassNotFoundException | BadPaddingException | InvalidAlgorithmParameterException e) {
+            throw new RuntimeException(e);
+        }
+        return ret;
+    }
+
+}

src/main/java/de/b00tload/tools/lastfmtospotifyplaylist/util/TokenHelper.java

@@ -2,18 +2,21 @@ package de.b00tload.tools.lastfmtospotifyplaylist.util;
 
 import se.michaelthelin.spotify.model_objects.credentials.AuthorizationCodeCredentials;
 
+import java.nio.file.Path;
+
+import static de.b00tload.tools.lastfmtospotifyplaylist.LastFMToSpotify.USER_HOME;
+import static de.b00tload.tools.lastfmtospotifyplaylist.LastFMToSpotify.configuration;
+
 public class TokenHelper {
     public static void saveTokens(AuthorizationCodeCredentials cred) {
-        //TODO: Save tokens
+        CryptoHelper.serializeEncrypted(cred, Path.of(USER_HOME, "/.lfm2s/spotify.lfm2scred"), CryptoHelper.createKeyFromPassword(configuration.get("cache.crypto")));
     }
 
-    public static String getAccessToken(){
+    public static AuthorizationCodeCredentials fetchTokens() {
-        //TODO: Read AccessToken
+        return (AuthorizationCodeCredentials) CryptoHelper.deserializeEncrypted(Path.of(USER_HOME, "/.lfm2s/spotify.lfm2scred"), CryptoHelper.createKeyFromPassword(configuration.get("cache.crypto")));
-        return "";
     }
 
-    public static String getRefreshToken(){
+    public static boolean existsTokens(){
-        //TODO: Read RefreshToken
+        return Path.of(USER_HOME, "/.lfm2s/spotify.lfm2scred").toFile().exists();
-        return "";
     }
 }