Using the Google Apps Script Cache Service for image blobs and objects above 100Kb

ChunkyCache.gs

function ImageCache(cache) {
  cache = ChunkyCache(cache || CacheService.getScriptCache());
  return {
    putBlob: function (key, value, timeout) {
      cache.put(key, Utilities.base64Encode(value.getBytes()), timeout);
    },
    getBlob: function (key) {
      var rawBytes = cache.get(key);
      if (rawBytes) {
        var blob = Utilities.newBlob("");
        blob.setBytes(Utilities.base64Decode(rawBytes));
        return blob;
      }
      return null;
    },
    removeBlob: function (key) {
      cache.remove(key)
    }
  }
}

function ChunkyCache(cache, chunkSize, defaultTimeout) {
  var _chunkSize = chunkSize || 100 * 1024;
  var _timeout = defaultTimeout || 21600000 - 420;
  return {
    put: function (key, value, timeout) {
      timeout = (timeout || _timeout)
      var asString = ('string' == typeof value);
      var data = asString ? value : JSON.stringify(value);
      var cSize = Math.floor(_chunkSize / 2);
      var itemTimeout = timeout + 5;
      var chunks = [];
      var index = 0;

      while (index < data.length) {
        cKey = key + "_" + index;
        chunks.push(cKey);
        cache.put(cKey, data.substr(index, cSize), itemTimeout + 5);
        index += cSize;
      }

      var manifest = JSON.stringify({
        chunkSize: chunkSize,
        chunks: chunks,
        asString: asString,
        length: data.length
      });

      cache.put(key, manifest, timeout);
    },

    get: function (key) {
      var superBlkCache = cache.get(key);
      if (superBlkCache != null) {
        var superBlk = JSON.parse(superBlkCache);
        chunks = superBlk.chunks.map(function (cKey) {
          return cache.get(cKey);
        });
        if (chunks.every(function (c) {
          return c != null;
        })) {
          if (superBlk.asString) {
            return chunks.join('');
          }
          return JSON.parse(chunks.join(''));
        }
      }
      return null;
    },

    remove: function (key) {
      cache.remove(key)
    }
  };
};

function testGetCacheFrom(){
  var sheet = SpreadsheetApp.getActiveSpreadsheet().getSheetByName('Data');
  var data = sheet.getDataRange().getValues();
  var chunky = ChunkyCache(CacheService.getDocumentCache(), 1024*90);
  chunky.put('Data', data, 120);
  var check = chunky.get('Data');
  var sheetPut = SpreadsheetApp.getActiveSpreadsheet().getSheetByName('Out');
  for (c in check) {
     sheetPut.appendRow(check[c]);
  }
}