datahub/src/backend.gdocs.js

123 lines
3.8 KiB
JavaScript

this.recline = this.recline || {};
this.recline.Backend = this.recline.Backend || {};
this.recline.Backend.GDocs = this.recline.Backend.GDocs || {};
(function($, my) {
my.__type__ = 'gdocs';
// ## Google spreadsheet backend
//
// Fetch data from a Google Docs spreadsheet.
//
// Dataset must have a url attribute pointing to the Gdocs or its JSON feed e.g.
// <pre>
// var dataset = new recline.Model.Dataset({
// url: 'https://docs.google.com/spreadsheet/ccc?key=0Aon3JiuouxLUdGlQVDJnbjZRSU1tUUJWOUZXRG53VkE#gid=0'
// },
// 'gdocs'
// );
//
// var dataset = new recline.Model.Dataset({
// url: 'https://spreadsheets.google.com/feeds/list/0Aon3JiuouxLUdDQwZE1JdV94cUd6NWtuZ0IyWTBjLWc/od6/public/values?alt=json'
// },
// 'gdocs'
// );
// </pre>
//
// @return object with two attributes
//
// * fields: array of Field objects
// * records: array of objects for each row
my.fetch = function(dataset) {
var dfd = $.Deferred();
var url = my.getSpreadsheetAPIUrl(dataset.url);
$.getJSON(url, function(d) {
result = my.parseData(d);
var fields = _.map(result.fields, function(fieldId) {
return {id: fieldId};
});
dfd.resolve({
records: result.records,
fields: fields,
useMemoryStore: true
});
});
return dfd.promise();
};
// ## parseData
//
// Parse data from Google Docs API into a reasonable form
//
// :options: (optional) optional argument dictionary:
// columnsToUse: list of columns to use (specified by field names)
// colTypes: dictionary (with column names as keys) specifying types (e.g. range, percent for use in conversion).
// :return: tabular data object (hash with keys: field and data).
//
// Issues: seems google docs return columns in rows in random order and not even sure whether consistent across rows.
my.parseData = function(gdocsSpreadsheet) {
var options = {};
if (arguments.length > 1) {
options = arguments[1];
}
var results = {
fields: [],
records: []
};
// default is no special info on type of columns
var colTypes = {};
if (options.colTypes) {
colTypes = options.colTypes;
}
if (gdocsSpreadsheet.feed.entry.length > 0) {
for (var k in gdocsSpreadsheet.feed.entry[0]) {
if (k.substr(0, 3) == 'gsx') {
var col = k.substr(4);
results.fields.push(col);
}
}
}
// converts non numberical values that should be numerical (22.3%[string] -> 0.223[float])
var rep = /^([\d\.\-]+)\%$/;
results.records = _.map(gdocsSpreadsheet.feed.entry, function(entry) {
var row = {};
_.each(results.fields, function(col) {
var _keyname = 'gsx$' + col;
var value = entry[_keyname]['$t'];
// if labelled as % and value contains %, convert
if (colTypes[col] == 'percent') {
if (rep.test(value)) {
var value2 = rep.exec(value);
var value3 = parseFloat(value2);
value = value3 / 100;
}
}
row[col] = value;
});
return row;
});
return results;
};
// Convenience function to get GDocs JSON API Url from standard URL
my.getSpreadsheetAPIUrl = function(url) {
if (url.indexOf('feeds/list') != -1) {
return url;
} else {
// https://docs.google.com/spreadsheet/ccc?key=XXXX#gid=0
var regex = /.*spreadsheet\/ccc?.*key=([^#?&+]+).*/;
var matches = url.match(regex);
if (matches) {
var key = matches[1];
var worksheet = 1;
var out = 'https://spreadsheets.google.com/feeds/list/' + key + '/' + worksheet + '/public/values?alt=json';
return out;
} else {
alert('Failed to extract gdocs key from ' + url);
}
}
};
}(jQuery, this.recline.Backend.GDocs));