Bring back upload route to keep e2e happy

let's maybe remove it in next release

src/apps.js

@@ -93,6 +93,7 @@ exports = module.exports = {
     listEventlog,
 
     downloadFile,
+    uploadFile,
 
     writeConfig,
     loadConfig,
@@ -2887,6 +2888,32 @@ async function downloadFile(app, filePath) {
     return { stream: stdoutStream, filename, size };
 }
 
+async function uploadFile(app, sourceFilePath, destFilePath) {
+    assert.strictEqual(typeof app, 'object');
+    assert.strictEqual(typeof sourceFilePath, 'string');
+    assert.strictEqual(typeof destFilePath, 'string');
+
+    // the built-in bash printf understands "%q" but not /usr/bin/printf.
+    // ' gets replaced with '\'' . the first closes the quote and last one starts a new one
+    const escapedDestFilePath = await shell.exec('uploadFile', `printf %q '${destFilePath.replace(/'/g, '\'\\\'\'')}'`, { shell: '/bin/bash' });
+    debug(`uploadFile: ${sourceFilePath} -> ${escapedDestFilePath}`);
+
+    const execId = await createExec(app, { cmd: [ 'bash', '-c', `cat - > ${escapedDestFilePath}` ], tty: false });
+    const destStream = await startExec(app, execId, { tty: false });
+
+    return new Promise((resolve, reject) => {
+        const done = once(error => reject(new BoxError(BoxError.FS_ERROR, error.message)));
+
+        const sourceStream = fs.createReadStream(sourceFilePath);
+        sourceStream.on('error', done);
+        destStream.on('error', done);
+
+        destStream.on('finish', resolve);
+
+        sourceStream.pipe(destStream);
+    });
+}
+
 async function writeConfig(app) {
     assert.strictEqual(typeof app, 'object');