Windshaft-cartodb/lib/cartodb/api/query_tables_api.js
Raul Ochoa 76cbc2f863 Improve PgQueryRunner public run method
Last param is callback function, receiving err + result, no need to
keep passing two functions, the query handler and the final callback.

It should be easier to understand now as query handler was in a position
where it had to know about receiving a callback, that was exposing an
implementation detail of PgQueryRunner.
2015-12-30 17:44:49 +01:00

97 lines
3.3 KiB
JavaScript

function QueryTablesApi(pgQueryRunner) {
this.pgQueryRunner = pgQueryRunner;
}
var affectedTableRegexCache = {
bbox: /!bbox!/g,
scale_denominator: /!scale_denominator!/g,
pixel_width: /!pixel_width!/g,
pixel_height: /!pixel_height!/g
};
module.exports = QueryTablesApi;
QueryTablesApi.prototype.getAffectedTablesInQuery = function (username, sql, callback) {
var query = 'SELECT CDB_QueryTablesText($windshaft$' + prepareSql(sql) + '$windshaft$)';
this.pgQueryRunner.run(username, query, function handleAffectedTablesInQueryRows (err, rows) {
if (err){
var msg = err.message ? err.message : err;
callback(new Error('could not fetch source tables: ' + msg));
return;
}
// This is an Array, so no need to split into parts
var tableNames = rows[0].cdb_querytablestext;
return callback(null, tableNames);
});
};
QueryTablesApi.prototype.getAffectedTablesAndLastUpdatedTime = function (username, sql, callback) {
var query = [
'WITH querytables AS (',
'SELECT * FROM CDB_QueryTablesText($windshaft$' + prepareSql(sql) + '$windshaft$) as tablenames',
')',
'SELECT (SELECT tablenames FROM querytables), EXTRACT(EPOCH FROM max(updated_at)) as max',
'FROM CDB_TableMetadata m',
'WHERE m.tabname = any ((SELECT tablenames from querytables)::regclass[])'
].join(' ');
this.pgQueryRunner.run(username, query, function handleAffectedTablesAndLastUpdatedTimeRows (err, rows) {
if (err || rows.length === 0) {
var msg = err.message ? err.message : err;
callback(new Error('could not fetch affected tables or last updated time: ' + msg));
return;
}
var result = rows[0];
// This is an Array, so no need to split into parts
var tableNames = result.tablenames;
var lastUpdatedTime = result.max || 0;
callback(null, {
affectedTables: tableNames,
lastUpdatedTime: lastUpdatedTime * 1000
});
});
};
QueryTablesApi.prototype.getLastUpdatedTime = function (username, tableNames, callback) {
if (!Array.isArray(tableNames) || tableNames.length === 0) {
return callback(null, 0);
}
var query = [
'SELECT EXTRACT(EPOCH FROM max(updated_at)) as max',
'FROM CDB_TableMetadata m WHERE m.tabname = any (ARRAY[',
tableNames.map(function(t) { return "'" + t + "'::regclass"; }).join(','),
'])'
].join(' ');
this.pgQueryRunner.run(username, query, function handleLastUpdatedTimeRows (err, rows) {
if (err) {
var msg = err.message ? err.message : err;
return callback(new Error('could not fetch affected tables or last updated time: ' + msg));
}
// when the table has not updated_at means it hasn't been changed so a default last_updated is set
var lastUpdated = 0;
if (rows.length !== 0) {
lastUpdated = rows[0].max || 0;
}
return callback(null, lastUpdated*1000);
});
};
function prepareSql(sql) {
return sql
.replace(affectedTableRegexCache.bbox, 'ST_MakeEnvelope(0,0,0,0)')
.replace(affectedTableRegexCache.scale_denominator, '0')
.replace(affectedTableRegexCache.pixel_width, '1')
.replace(affectedTableRegexCache.pixel_height, '1')
;
}