FlashAir Media Uploader

Flash Air Media Uploader.md

FlashAir Media Uploader

Script that iterates over all photos and movies saved on an SD card and uploads them to an HTTP endpoint. Uploaded files are renamed. A tiny node server receives the files.

package.json

{
  "name": "file_receiver",
  "version": "0.0.0",
  "description": "receive files uploaded by flashair",
  "main": "server.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "flo",
  "license": "ISC",
  "dependencies": {
    "formidable": "^1.1.1",
    "winston": "^2.3.1"
  }
}

server.js

/* File Receiver
 * Handles uploads from flashair.
 * Install dependencies with npm using the package.json file: https://docs.npmjs.com/cli/install
 * Start with node: https://nodejs.org/en/
 */

var util = require('util')
var spawn = require('child_process').spawn;
var http = require('http');
var formidable = require('formidable');
var fs = require('fs');
var winston = require('winston');

var uploadPath = '/media/main/Bilder/FlashAir/';

// Create log file
winston.add(winston.transports.File, { filename: '/home/pi/upload/winston.json' });

// Redirect all errors into log file
function errorHandler(err) {
  if(err) {
    winston.error(err);
    throw err;
  }
}

winston.info('Starting file receiver');

http.createServer(function (req, res) {
  // Handle upload requests
  if (req.url == '/upload') {
    winston.info('Upload request');

    var form = new formidable.IncomingForm();
    form.parse(req, function (err, fields, files) {
      // console.log(util.inspect(files, false, null));
      if(!files.file) {
        winston.error('No file in request');
        res.writeHead(400);
        res.end('No file in request');
        return;
      }
      
      var readStream = fs.createReadStream(files.file.path);
      var writeStream = fs.createWriteStream(uploadPath + files.file.name);

      winston.info('File uploaded to: ' + files.file.path)
      readStream.on('error', errorHandler);
      writeStream.on('error', errorHandler);
      readStream.on('close', function () {
        winston.info('File moved to destination with name: ' + files.file.name)
        res.end('Done');

        fs.unlink(files.file.path, function(err) {
          errorHandler(err);
          if(err) return;
          winston.info('Removed temporary file');
        });

        /* I run a backup and sort script at this point.
         * Feel free to uncomment this and insert your own.
        winston.info('Running backup and sorting');
        spawn('bash', [ '/home/pi/backup/backup.sh' ]);
        */
      });

      readStream.pipe(writeStream);
    });
  } else {
    // For other requests show a basic html upload form
    res.writeHead(200, {'Content-Type': 'text/html'});
    res.write('<form action="upload" method="post" enctype="multipart/form-data">');
    res.write('<input type="file" name="file"><br>');
    res.write('<input type="submit">');
    res.write('</form>');
    return res.end();
  }

}).listen(3333);

upload.lua

-- FlashAir Lua script
-- Copy to 'Lua' folder on your SD card
-- Set as RUN_SCRIPT/SD_EVENT in your SD_WLAN/CONFIG file:
-- LUA_RUN_SCRIPT=/Lua/upload.lua
-- LUA_SD_EVENT=/Lua/upload.lua

local httpendpoint = 'http://192.168.1.13:3333/upload'
local folder = '/DCIM'

-- Recursively iterate through directories
function walk_directory(folder, extension)
  for file in lfs.dir(folder) do
    -- Not sure if this is necessary, but it keeps 'LUA : not enough memory' out of the log
    collectgarbage()

    -- Find file path and type
    local path = folder .. "/" .. file
    local attr = lfs.attributes(path)
    if attr.mode == "file" then
      handle_file(file, path, extension)
    elseif attr.mode == "directory" then
      walk_directory(path, extension)
    end
  end
end

-- Check file for upload, upload and rename it
function handle_file(file, path, extension)
  -- Find files not yet marked as "_SAVED"
  if string.sub(path, -4, -1) ~= extension then return end
  if string.sub(path, -10, -5) == "_SAVED" then return end

  -- Upload file to HTTP server
  local boundary = '--61141483716826'
  local contenttype = 'multipart/form-data; boundary=' .. boundary
  -- <!--WLANSDFILE--> will be replaced with file content
  local body = '--'.. boundary .. '\r\n'
   ..'Content-Disposition: form-data; name=\"file\"; filename=\"'..file ..'\"\r\n'
   ..'Content-Type: text/plain\r\n'
   ..'\r\n'
   ..'<!--WLANSDFILE-->\r\n'
   ..'--' .. boundary .. '--\r\n'

  -- Exclude size of placeholder
  local size = lfs.attributes(path, 'size') + string.len(body) - 17
  -- Execute request (returns response body, response code, response header)
  local b, c, h = fa.request {
    url = httpendpoint,
    method = 'POST',
    headers = {['Content-Length'] = tostring(size),
    ['Content-Type'] = contenttype},
    file = path,
    body = body
  }
  b, h = nil
  collectgarbage()
  if (c ~= 200) then return end

  -- Mark file as "_SAVED"
  fa.rename(path, string.sub(path, 0, -5) .. '_SAVED' .. string.sub(path, -4, -1))
end

-- Keep checking WLAN status until it is up or 30 seconds passed
for i = 1, 300 do
  -- Allow card to connect with WLAN
  sleep(100)

  -- Check if WLAN is up
  if fa.WlanLink() == 1 then
    -- Upload pictures first
    walk_directory(folder, '.JPG')
    -- Upload movies later, they are much larger and might fail
    walk_directory(folder, '.MOV')
    break
  end
end