Added feature to export servers list

src/servers/services/ServersExporter.js

@@ -0,0 +1,54 @@
+import Storage from '../../utils/Storage';
+import jsonexport from 'jsonexport/dist';
+import { dissoc, values } from 'ramda';
+
+const SERVERS_STORAGE_KEY = 'servers';
+
+const saveCsv = (window, csv) => {
+  const { navigator, document } = window;
+  const filename = 'shlink-servers.csv';
+  const blob = new Blob([csv], { type: 'text/csv;charset=utf-8;' });
+
+  // IE10 and IE11
+  if (navigator.msSaveBlob) {
+    navigator.msSaveBlob(blob, filename);
+    return;
+  }
+
+  // Modern browsers
+  const link = document.createElement('a');
+  const url = URL.createObjectURL(blob);
+  link.setAttribute('href', url);
+  link.setAttribute('download', filename);
+  link.style.visibility = 'hidden';
+  document.body.appendChild(link);
+  link.click();
+  document.body.removeChild(link);
+};
+
+export class ServersExporter {
+  constructor(storage, window, jsonexport) {
+    this.storage = storage;
+    this.window = window;
+    this.jsonexport = jsonexport;
+  }
+
+  exportServers = async () => {
+    const servers = values(this.storage.get(SERVERS_STORAGE_KEY) || {}).map(
+      dissoc('id')
+    );
+
+    try {
+      const csv = await new Promise((resolve, reject) => {
+        this.jsonexport(servers, (err, csv) => err ? reject(err) : resolve(csv));
+      });
+
+      saveCsv(this.window, csv);
+    } catch (e) {
+      // FIXME Handle error
+      console.error(e);
+    }
+  };
+}
+
+export default new ServersExporter(Storage, global.window, jsonexport);