dbcrawler/generate_schema.js

crawls mysql database and creates insert queries or returns data from multiple table depending on the relationship information of the tables provided

var generateSqlDefinition = require('sql-generate')
var dbconfig = require('./config/dbconfig');
var Path = require('path');
var Async = require('async');
var Fs = require('fs');
var RequireFromString = require('require-from-string')
    /////////////////////////////////////////////////////////
    //functions used in generate schema water fall starts here

function actuallyGenerateSchema(options, callback) {
    var usingConfig = options.dbconfig || dbconfig;
    var opts = {
        dsn: 'mysql://' + usingConfig.user + ':' + usingConfig.password + '@' + usingConfig.host + '/' + usingConfig.database,
        dialect: 'mysql',
        append: "sql.setDialect('mysql');",
        omitComments: true
    };
    generateSqlDefinition(opts, function (err, stats) {
        if (err) {
            return callback(err);
        }
        if (!stats || !stats.buffer) {
            return callback(new Error('not able to generate schema'));
        }
        var schema;
	var o= { 
	    //passing prependPaths forces the module compilation in require from string function to find
	    //sql module in node_modules directory of dbcrawler
	    //this solves the problem of dbcrawler trying to find sql module when running globally
	    prependPaths:[Path.join(__dirname,'./node_modules')]
	};
        try {
            schema = RequireFromString(stats.buffer.toString(),o);
        } catch (ex) {
            return callback(new Error('not able to parse schema file'));
        }
        var returnOpts = {
            data: schema
        };
        return callback(null, returnOpts);
    });
}

//functions used in generate schema water fall endss here
//////////////////////////////////////////////////////////

function generateSchema(options, cb) {
    var directory = '';
    Async.waterfall([
        Async.constant(options),
        actuallyGenerateSchema
    ], cb);
}

module.exports = {
    generate: generateSchema
};

(function () {
    if (require.main == module) {
        generateSchema({}, function (err, stats) {
            console.log(stats)
        });
    }
})();