Add legacy support for KWallet maps

In the ongoing migration from KWallet to QtKeychain in Plasma,
in order to migrate without too strong rewrites and most important
have the existing stored data still working, (some secrets actually have
the structure of multiple key value maps) make reading from map
still work. return it as a json serialized string, which is also how
the kwallet compatibility layer stores maps on secretservice.

This is only supported while reading, so when writing again it
will be written directly as a serialized json string. this makes
an implicit data migration which will make easier to go completely
away from kwallet.

Author: notmart

qtkeychain/keychain_p.h

@@ -36,7 +36,7 @@ class JobPrivate : public QObject
 {
     Q_OBJECT
 public:
-    enum Mode { Text, Binary };
+    enum Mode { Text, Binary, Map };
 
     virtual void scheduledStart() = 0;
 

qtkeychain/keychain_unix.cpp

@@ -420,16 +420,19 @@ void ReadPasswordJobPrivate::kwalletEntryTypeFinished(QDBusPendingCallWatcher *w
     case Stream:
         mode = Binary;
         break;
-    case Map:
-        q->emitFinishedWithError(EntryNotFound, tr("Unsupported entry type 'Map'"));
-        return;
+    case KWalletEntryType::Map: {
+        mode = JobPrivate::Map;
+        break;
+    }
     default:
         q->emitFinishedWithError(OtherError, tr("Unknown kwallet entry type '%1'").arg(value));
         return;
     }
 
     const auto nextReply = (mode == Text)
             ? QDBusPendingCall(iface->readPassword(walletHandle, q->service(), key, q->service()))
+            : (mode == JobPrivate::Map)
+            ? QDBusPendingCall(iface->readMap(walletHandle, q->service(), key, q->service()))
             : QDBusPendingCall(iface->readEntry(walletHandle, q->service(), key, q->service()));
     auto nextWatcher = new QDBusPendingCallWatcher(nextReply, this);
     connect(nextWatcher, &QDBusPendingCallWatcher::finished, this,
@@ -444,6 +447,20 @@ void ReadPasswordJobPrivate::kwalletFinished(QDBusPendingCallWatcher *watcher)
             if (reply.isValid()) {
                 data = reply.value();
             }
+        } else if (mode == Map) {
+            QDBusPendingReply<QByteArray> reply = *watcher;
+            if (reply.isValid()) {
+                QByteArray v = reply.value();
+                QMap<QString, QString> map;
+                QDataStream ds(&v, QIODevice::ReadOnly);
+                ds >> map;
+                QJsonObject json;
+                for (auto it = map.constBegin(); it != map.constEnd(); ++it) {
+                    json.insert(it.key(), it.value());
+                }
+                QJsonDocument doc(json);
+                data = doc.toJson(QJsonDocument::Compact);
+            }
         } else {
             QDBusPendingReply<QString> reply = *watcher;
             if (reply.isValid()) {