Add implementation to create public share for file.

dropbox/src/main/java/ch/cyberduck/core/dropbox/DropboxPublicShareUrlProvider.java

@@ -0,0 +1,77 @@
+package ch.cyberduck.core.dropbox;
+
+/*
+ * Copyright (c) 2002-2019 iterate GmbH. All rights reserved.
+ * https://cyberduck.io/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+import ch.cyberduck.core.DescriptiveUrl;
+import ch.cyberduck.core.LocaleFactory;
+import ch.cyberduck.core.PasswordCallback;
+import ch.cyberduck.core.Path;
+import ch.cyberduck.core.exception.BackgroundException;
+import ch.cyberduck.core.exception.UnsupportedException;
+import ch.cyberduck.core.features.PromptUrlProvider;
+
+import org.apache.log4j.Logger;
+
+import java.net.URI;
+import java.text.MessageFormat;
+
+import com.dropbox.core.DbxException;
+import com.dropbox.core.v2.sharing.DbxUserSharingRequests;
+import com.dropbox.core.v2.sharing.RequestedVisibility;
+import com.dropbox.core.v2.sharing.SharedLinkMetadata;
+import com.dropbox.core.v2.sharing.SharedLinkSettings;
+
+public class DropboxPublicShareUrlProvider implements PromptUrlProvider<Void, Void> {
+    private static final Logger log = Logger.getLogger(DropboxPublicShareUrlProvider.class);
+
+    private final DropboxSession session;
+
+    public DropboxPublicShareUrlProvider(final DropboxSession session) {
+        this.session = session;
+    }
+
+    @Override
+    public DescriptiveUrl toDownloadUrl(final Path file, final Void options, final PasswordCallback callback) throws BackgroundException {
+        try {
+            final SharedLinkMetadata share = new DbxUserSharingRequests(session.getClient()).createSharedLinkWithSettings(file.getAbsolute(),
+                SharedLinkSettings.newBuilder().withRequestedVisibility(RequestedVisibility.PUBLIC).build());
+            if(log.isDebugEnabled()) {
+                log.debug(String.format("Created shared link %s", share));
+            }
+            return new DescriptiveUrl(URI.create(share.getUrl()), DescriptiveUrl.Type.http,
+                MessageFormat.format(LocaleFactory.localizedString("{0} URL"),
+                    LocaleFactory.localizedString("Public Share", "Dropbox"))
+            );
+        }
+        catch(DbxException e) {
+            throw new DropboxExceptionMappingService().map(e);
+        }
+    }
+
+    @Override
+    public DescriptiveUrl toUploadUrl(final Path file, final Void options, final PasswordCallback callback) throws BackgroundException {
+        throw new UnsupportedException();
+    }
+
+    @Override
+    public boolean isSupported(final Path file, final Type type) {
+        switch(type) {
+            case download:
+                return file.isFile();
+        }
+        return false;
+    }
+}