grille/lib/worksheet.js

Simple CMS using Google Spreadsheets

'use strict';

var GoogleSpreadsheet = require("google-spreadsheet");
var ValidationError = require('./errors/validation.js');

/**
 * Represents a single Worksheet within a Google Spreadsheet.
 * Contains functionality for extracting and casting data in the worksheet.
 *
 * @param String id The hash Google uses for representing the containing spreadsheet
 * @param String name The tab name for this Worksheet
 */
var Worksheet = function(id, name) {
  this.spreadsheet = new GoogleSpreadsheet(id);
  this.name = name;

  this.last_updated = null;
};

Worksheet.parseWorksheetData = function(row) {
  var parsed = {};
  var descriptors = Worksheet.removeExcessKeys(row.shift());

  row.forEach(function(row) {
    row = Worksheet.removeExcessKeys(row);
    row = Worksheet.convertKeys(descriptors, row);

    parsed[row.id] = row;
  });

  return parsed;
};

Worksheet.removeExcessKeys = function(row) {
  delete row._xml;
  delete row._links;
  delete row.content;
  delete row.save;
  delete row.del;
  delete row.title;

  return row;
};

Worksheet.convertKeys = function(descriptors, row) {
  Object.keys(descriptors).forEach(function(column) {
    var type = descriptors[column];

    switch(type) {
      case 'ignore':
        delete row[column];

        break;

      case 'integer':
        row[column] = Math.floor(row[column]);

        break;

      case 'float':
        row[column] = parseFloat(row[column]);

        break;

      case 'string':
        row[column] = row[column];

        break;

      case 'boolean':
        row[column] = row[column].toUpperCase();

        if (row[column] !== 'TRUE' && row[column] !== 'FALSE') {
          throw new ValidationError("Not a boolean");
        }

        row[column] = row[column] === 'TRUE';

        break;

      case 'array':
        if (row[column]) {
          try {
            row[column] = JSON.parse(row[column]);
          } catch(e) {
            throw new ValidationError("Unable to parse JSON: " + row[column]);
          }

          if (!Array.isArray(row[column])) {
            throw new ValidationError("Data is not of type array: " + column);
          }
        } else {
          row[column] = [];
        }

        break;

      case 'array.integer':
        if (row[column]) {
          try {
            row[column] = JSON.parse(row[column]);
          } catch(e) {
            throw new ValidationError("Unable to parse JSON: " + row[column]);
          }

          if (!Array.isArray(row[column])) {
            throw new ValidationError("Data is not of type array: " + column);
          }

          row[column].forEach(function(value) {
            if (typeof value !== 'number' || value % 1 !== 0) {
              throw new ValidationError("Not an array of integers");
            }
          });
        } else {
          row[column] = [];
        }

        break;

      case 'array.string':
        if (row[column]) {
          try {
            row[column] = JSON.parse(row[column]);
          } catch(e) {
            throw new ValidationError("Unable to parse JSON: " + row[column]);
          }

          if (!Array.isArray(row[column])) {
            throw new ValidationError("Data is not of type array: " + column);
          }

          row[column].forEach(function(value) {
            if (typeof value !== 'string') {
              throw new ValidationError("Not an array of strings");
            }
          });
        } else {
          row[column] = [];
        }

        break;

      case 'array.boolean':
        if (row[column]) {
          try {
            row[column] = JSON.parse(row[column]);
          } catch(e) {
            throw new ValidationError("Unable to parse JSON: " + row[column]);
          }

          if (!Array.isArray(row[column])) {
            throw new ValidationError("Data is not of type array: " + column);
          }

          row[column].forEach(function(value) {
            if (typeof value !== 'boolean') {
              throw new ValidationError("Not an array of booleans");
            }
          });
        } else {
          row[column] = [];
        }

        break;

      case 'array.float':
        if (row[column]) {
          try {
            row[column] = JSON.parse(row[column]);
          } catch(e) {
            throw new ValidationError("Unable to parse JSON: " + row[column]);
          }

          if (!Array.isArray(row[column])) {
            throw new ValidationError("Data is not of type array: " + column);
          }

          row[column].forEach(function(value) {
            if (typeof value !== 'number') {
              throw new ValidationError("Not an array of floats");
            }
          });
        } else {
          row[column] = [];
        }

        break;

      case 'json':
        if (row[column]) {
          try {
            row[column] = JSON.parse(row[column]);
          } catch(e) {
            throw new ValidationError("Unable to parse JSON: " + row[column]);
          }
        } else {
          row[column] = null;
        }

        break;

      default:
        console.log("NOTICE: Unable to parse data type, assuming string", JSON.stringify(type));

        row[column] = row[column];

        break;
    }
  });

  return row;
};

Worksheet.getIndex = function(name, data) {
  for (var i = 0; i < data.worksheets.length; i++) {
    if (data.worksheets[i].title === name) {
      return i + 1; // Google Spreadsheet uses 1-based indexes
    }
  }

  return null;
};

Worksheet.prototype.load = function(callback) {
  var self = this;

  this.getWorksheetIndex(function(err, sheet) {
    if (err) {
      return callback(err);
    }

    self.spreadsheet.getRows(sheet, function(err, data) {
      if (err) {
        return callback(err);
      }

      callback(null, Worksheet.parseWorksheetData(data));
    });
  });
};

// TODO: This should be called once per document load
Worksheet.prototype.getWorksheetIndex = function(callback) {
  var self = this;

  self.spreadsheet.getInfo(function(err, data) {
    if (err) {
      return callback(err);
    }

    self.last_updated = new Date(data.updated);

    var worksheet_index = Worksheet.getIndex(self.name, data);

    if (!worksheet_index) {
      return callback("Couldn't find a worksheet tab named '" + self.name + "'!");
    }

    callback(null, worksheet_index);
  });
};

module.exports = Worksheet;