CartoDB-SQL-API/app/models/formats/arraybuffer.js
2014-08-02 20:27:05 +02:00

83 lines
2.2 KiB
JavaScript

var pg = require('./pg'),
ArrayBufferSer = require("../bin_encoder"),
_ = require('underscore');
function BinaryFormat() {}
BinaryFormat.prototype = new pg('arraybuffer');
BinaryFormat.prototype._contentType = "application/octet-stream";
BinaryFormat.prototype._extractTypeFromName = function(name) {
var g = name.match(new RegExp(/.*__(uintclamp|uint|int|float)(8|16|32)/i))
if(g && g.length == 3) {
var typeName = g[1] + g[2];
return ArrayBufferSer.typeNames[typeName];
}
};
BinaryFormat.prototype.transform = function(result, options, callback) {
var total_rows = result.rowCount;
var rows = result.rows;
// get headers
if(!total_rows) {
callback(null, new Buffer(0));
return;
}
var headersNames = Object.keys(rows[0]);
var headerTypes = [];
if(_.contains(headersNames, 'the_geom')) {
callback(new Error("geometry types are not supported"), null);
return;
}
try {
// get header types (and guess from name)
for(var i = 0; i < headersNames.length; ++i) {
var r = rows[0];
var n = headersNames[i];
if(typeof(r[n]) == 'string') {
headerTypes.push(ArrayBufferSer.STRING);
} else if(typeof(r[n]) == 'object') {
var t = this._extractTypeFromName(n);
t = t == undefined ? ArrayBufferSer.FLOAT32: t;
headerTypes.push(ArrayBufferSer.BUFFER + t);
} else {
var t = this._extractTypeFromName(n);
headerTypes.push(t == undefined ? ArrayBufferSer.FLOAT32: t);
}
}
// pack the data
var header = new ArrayBufferSer(ArrayBufferSer.STRING, headersNames);
var data = [header];
for(var i = 0; i < headersNames.length; ++i) {
var d = [];
var n = headersNames[i];
for(var r = 0; r < total_rows; ++r) {
var row = rows[r][n];
if(headerTypes[i] > ArrayBufferSer.BUFFER) {
row = new ArrayBufferSer(headerTypes[i] - ArrayBufferSer.BUFFER, row);
}
d.push(row);
}
var b = new ArrayBufferSer(headerTypes[i], d);
data.push(b);
}
// create the final buffer
var all = new ArrayBufferSer(ArrayBufferSer.BUFFER, data);
callback(null, all.buffer);
} catch(e) {
callback(e, null);
}
};
module.exports = BinaryFormat;