#98, working sync setup from server to desktop instance + refactoring of DB initialization

src/routes/api/setup.js

@@ -1,13 +1,74 @@
 "use strict";
 
 const sqlInit = require('../../services/sql_init');
+const sql = require('../../services/sql');
+const cls = require('../../services/cls');
+const tmp = require('tmp-promise');
+const http = require('http');
+const fs = require('fs');
+const log = require('../../services/log');
+const DOCUMENT_PATH = require('../../services/data_dir').DOCUMENT_PATH;
+const sourceIdService = require('../../services/source_id');
+const url = require('url');
 
-async function setup(req) {
+async function setupNewDocument(req) {
     const { username, password } = req.body;
 
     await sqlInit.createInitialDatabase(username, password);
 }
 
+async function setupSyncFromServer(req) {
+    const { serverAddress, username, password } = req.body;
+
+    const tempFile = await tmp.file();
+
+    await new Promise((resolve, reject) => {
+        const file = fs.createWriteStream(tempFile.path);
+        const parsedAddress = url.parse(serverAddress);
+
+        const options = {
+            method: 'GET',
+            protocol: parsedAddress.protocol,
+            host: parsedAddress.hostname,
+            port: parsedAddress.port,
+            path: '/api/sync/document',
+            auth: username + ':' + password
+        };
+
+        log.info("Getting document from: " + serverAddress + JSON.stringify(options));
+
+        http.request(options, function(response) {
+            response.pipe(file);
+
+            file.on('finish', function() {
+                log.info("Document download finished, closing & renaming.");
+
+                file.close(() => { // close() is async, call after close completes.
+                    fs.rename(tempFile.path, DOCUMENT_PATH, async () => {
+                        cls.reset();
+
+                        await sqlInit.initDbConnection();
+
+                        // we need to generate new source ID for this instance, otherwise it will
+                        // match the original server one
+                        await sql.transactional(async () => {
+                            await sourceIdService.generateSourceId();
+                        });
+
+                        resolve();
+                    });
+                });
+            });
+        }).on('error', function(err) { // Handle errors
+            fs.unlink(tempFile.path); // Delete the file async. (But we don't check the result)
+
+            reject(err.message);
+            log.error(err.message);
+        }).end();
+    });
+}
+
 module.exports = {
-    setup
+    setupNewDocument,
+    setupSyncFromServer
 };