Ci.nsIZIGOROu

Storage 用の ResultSet 展開ライブラリ作ってみた

Mozilla, Storage, JavaScript | 19:34 |

ソースコード

var StorageResultSetExtractor = function(stmt) {
  this.stmt = stmt;
};

StorageResultSetExtractor.prototype = {
  rowInfoCache: null,
  rowData: null,
  getRowInfo: function() {
	if (this.rowInfoCache) {
	  return this.rowInfoCache;
	}

	var rowInfo = [];
	for (var idx = 0, colCnt = this.stmt.columnCount; idx < colCnt; idx++) {
	  rowInfo.push({ name: this.stmt.getColumnName(idx), type: this.stmt.getTypeOfIndex(idx) });
	}

	this.rowInfoCache = rowInfo;
	return this.rowInfoCache;
  },
  next: function() {
	if (!this.stmt.executeStep())
	  return false;

	var rowInfo = this.getRowInfo();
	var rowData = {};

	for (var cidx = 0, clen = rowInfo.length; cidx < clen; cidx++) {
	  switch (rowInfo[cidx].type) {
		case this.stmt.VALUE_TYPE_NULL:
		  rowData[rowInfo[cidx].name] = null;
		  break;
		case this.stmt.VALUE_TYPE_INTEGER:
		  rowData[rowInfo[cidx].name] = this.stmt.getInt32(cidx);
		  break;
		case this.stmt.VALUE_TYPE_FLOAT:
		  rowData[rowInfo[cidx].name] = this.stmt.getDouble(cidx);
		  break;
		case this.stmt.VALUE_TYPE_TEXT:
		  rowData[rowInfo[cidx].name] = this.stmt.getUTF8String(cidx);
		  break;
		case this.stmt.VALUE_TYPE_BLOB:
		  var dataSize = { aDataSize: null };
		  var data = { aData: null };
		  this.stmt.getBlob(cidx, dataSize, data);
		  rowData[rowInfo[cidx].name] = data.aData;
		  break;
		default:
		  ;
	  }
	}

	this.rowData = rowData;
	return true;
  },
  item: function() {
	return this.rowData;
  }
};

使い方

var storage = Cc["@mozilla.org/storage/service;1"].getService(Ci.mozIStorageService);
var conn = storage.openDatabase(aDBFile);
var stmt = conn.createStatement("SELECT * FROM foo;");

var extractor = new StorageResultSetExtractor(stmt);
var result = [];

while (extractor.next()) {
  result.push(extractor.item());
}

result[0].colname; // これで値取れる

んー、まぁ今はここまで。本当はinflate/deflateとか出来るべきなんだろうなぁ。

ファイル関連の関数追加した

MozRepl | 16:36 |

function file(path) {
  var file = Cc["@mozilla.org/file/local;1"].createInstance(Ci.nsILocalFile);
  file.initWithPath(path);
  return file;
}

function url(aURL) {
  var ios = Cc["@mozilla.org/network/io-service;1"].getService(Ci.nsIIOService);
  var url = ios.newURI(aURL, null, null);
  return url;
}

function slurp(path) {
  var file = this.file(path);
  var fstream = Cc["@mozilla.org/network/file-input-stream;1"].createInstance(Ci.nsIFileInputStream);
  var sstream = Cc["@mozilla.org/scriptableinputstream;1"].createInstance(Ci.nsIScriptableInputStream);

  fstream.init(file, -1, 0, 0);
  sstream.init(fstream);

  var data = "";
  var str = sstream.read(4096);

  while (str.length > 0) {
	data += str;
	str = sstream.read(4096);
  }

  sstream.close();
  fstream.close();

  return data;
}

あとresourceに簡単に追加出来る関数はこんなん、

function createResource(alias, filepath) {
  var ioService = Cc["@mozilla.org/network/io-service;1"].getService(Ci.nsIIOService);
  var resProtocol = ioService.getProtocolHandler("resource").QueryInterface(Ci.nsIResProtocolHandler);
  var aliasFile = Cc["@mozilla.org/file/local;1"].createInstance(Ci.nsILocalFile);
  aliasFile.initWithPath(filepath);

  resProtocol.setSubstitution(alias, ioService.newFileURI(aliasFile));
}