CartoDB-SQL-API/app/controllers/query_controller.js
2015-12-07 09:40:51 +01:00

332 lines
13 KiB
JavaScript

'use strict';
var _ = require('underscore');
var step = require('step');
var assert = require('assert');
var PSQL = require('cartodb-psql');
var UserDatabaseService = require('../services/user_database_service');
var CdbRequest = require('../models/cartodb_request');
var formats = require('../models/formats');
var sanitize_filename = require('../utils/filename_sanitizer');
var generateMD5 = require('../utils/md5');
var queryMayWrite = require('../utils/query_may_write');
var getContentDisposition = require('../utils/content_disposition');
var setCrossDomain = require('../utils/cross_domain');
var generateCacheKey = require('../utils/cache_key_generator');
var handleException = require('../utils/error_handler');
var cdbReq = new CdbRequest();
var userDatabaseService = new UserDatabaseService();
function QueryController(metadataBackend, tableCache, statsd_client) {
this.metadataBackend = metadataBackend;
this.tableCache = tableCache;
this.statsd_client = statsd_client;
}
QueryController.prototype.route = function (app) {
app.all(global.settings.base_url + '/sql', this.handleQuery.bind(this));
app.all(global.settings.base_url + '/sql.:f', this.handleQuery.bind(this));
};
// jshint maxcomplexity:21
QueryController.prototype.handleQuery = function (req, res) {
var self = this;
// extract input
var body = (req.body) ? req.body : {};
var params = _.extend({}, req.query, body); // clone so don't modify req.params or req.body so oauth is not broken
var sql = params.q;
var limit = parseInt(params.rows_per_page);
var offset = parseInt(params.page);
var orderBy = params.order_by;
var sortOrder = params.sort_order;
var requestedFormat = params.format;
var format = _.isArray(requestedFormat) ? _.last(requestedFormat) : requestedFormat;
var requestedFilename = params.filename;
var filename = requestedFilename;
var requestedSkipfields = params.skipfields;
var cdbUsername = cdbReq.userByReq(req);
var skipfields;
var dp = params.dp; // decimal point digits (defaults to 6)
var gn = "the_geom"; // TODO: read from configuration file
var tableCacheItem;
if ( req.profiler ) {
req.profiler.start('sqlapi.query');
}
req.aborted = false;
req.on("close", function() {
if (req.formatter && _.isFunction(req.formatter.cancel)) {
req.formatter.cancel();
}
req.aborted = true; // TODO: there must be a builtin way to check this
});
function checkAborted(step) {
if ( req.aborted ) {
var err = new Error("Request aborted during " + step);
// We'll use status 499, same as ngnix in these cases
// see http://en.wikipedia.org/wiki/List_of_HTTP_status_codes#4xx_Client_Error
err.http_status = 499;
throw err;
}
}
try {
// sanitize and apply defaults to input
dp = (dp === "" || _.isUndefined(dp)) ? '6' : dp;
format = (format === "" || _.isUndefined(format)) ? 'json' : format.toLowerCase();
filename = (filename === "" || _.isUndefined(filename)) ? 'cartodb-query' : sanitize_filename(filename);
sql = (sql === "" || _.isUndefined(sql)) ? null : sql;
limit = (!_.isNaN(limit)) ? limit : null;
offset = (!_.isNaN(offset)) ? offset * limit : null;
// Accept both comma-separated string or array of comma-separated strings
if ( requestedSkipfields ) {
if ( _.isString(requestedSkipfields) ) {
skipfields = requestedSkipfields.split(',');
} else if ( _.isArray(requestedSkipfields) ) {
skipfields = [];
_.each(requestedSkipfields, function(ele) {
skipfields = skipfields.concat(ele.split(','));
});
}
} else {
skipfields = [];
}
//if ( -1 === supportedFormats.indexOf(format) )
if ( ! formats.hasOwnProperty(format) ) {
throw new Error("Invalid format: " + format);
}
if (!_.isString(sql)) {
throw new Error("You must indicate a sql query");
}
// initialise MD5 key of sql for cache lookups
var sql_md5 = generateMD5(sql);
// placeholder for connection
var pg;
// Database options
var dbopts = {};
var formatter;
if ( req.profiler ) {
req.profiler.done('init');
}
// 1. Get user database and related parameters
// 3. Get the list of tables affected by the query
// 4. Setup headers
// 5. Send formatted results back
step(
function getUserDBInfo() {
var options = {
req: req,
params: params,
checkAborted: checkAborted,
metadataBackend: self.metadataBackend,
cdbUsername: cdbUsername
};
userDatabaseService.getUserDatabase(options, this);
},
function queryExplain(err, userDatabase){
assert.ifError(err);
var next = this;
dbopts = userDatabase;
if ( req.profiler ) {
req.profiler.done('setDBAuth');
}
checkAborted('queryExplain');
pg = new PSQL(dbopts, {}, { destroyOnError: true });
// get all the tables from Cache or SQL
tableCacheItem = self.tableCache.get(sql_md5);
if (tableCacheItem) {
tableCacheItem.hits++;
return false;
} else {
var affectedTablesAndLastUpdatedTimeQuery = [
'WITH querytables AS (',
'SELECT * FROM CDB_QueryTablesText($quotesql$' + sql + '$quotesql$) 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(' ');
pg.query(affectedTablesAndLastUpdatedTimeQuery, function (err, resultSet) {
var tableNames = [];
var lastUpdatedTime = Date.now();
if (!err && resultSet.rowCount === 1) {
var result = resultSet.rows[0];
// This is an Array, so no need to split into parts
tableNames = result.tablenames;
if (Number.isFinite(result.max)) {
lastUpdatedTime = result.max * 1000;
}
} else {
var errorMessage = (err && err.message) || 'unknown error';
console.error("Error on query explain '%s': %s", sql, errorMessage);
}
return next(null, {
affectedTables: tableNames,
lastUpdatedTime: lastUpdatedTime
});
});
}
},
function setHeaders(err, result) {
assert.ifError(err);
if ( req.profiler ) {
req.profiler.done('queryExplain');
}
checkAborted('setHeaders');
// store explain result in local Cache
if ( ! tableCacheItem && result && result.affectedTables ) {
tableCacheItem = {
affected_tables: result.affectedTables,
last_modified: result.lastUpdatedTime,
// check if query may possibly write
may_write: queryMayWrite(sql),
// initialise hit counter
hits: 1
};
self.tableCache.set(sql_md5, tableCacheItem);
}
if ( !dbopts.authenticated && tableCacheItem ) {
var affected_tables = tableCacheItem.affected_tables;
for ( var i = 0; i < affected_tables.length; ++i ) {
var t = affected_tables[i];
if ( t.match(/\bpg_/) ) {
var e = new SyntaxError("system tables are forbidden");
e.http_status = 403;
throw(e);
}
}
}
var FormatClass = formats[format];
formatter = new FormatClass();
req.formatter = formatter;
// configure headers for given format
var use_inline = !requestedFormat && !requestedFilename;
res.header("Content-Disposition", getContentDisposition(formatter, filename, use_inline));
res.header("Content-Type", formatter.getContentType());
// allow cross site post
setCrossDomain(res);
// set cache headers
var ttl = 31536000; // 1 year time to live by default
var cache_policy = req.query.cache_policy;
if ( cache_policy === 'persist' ) {
res.header('Cache-Control', 'public,max-age=' + ttl);
} else {
if ( ! tableCacheItem || tableCacheItem.may_write ) {
// Tell clients this response is already expired
// TODO: prevent cache_policy from overriding this ?
ttl = 0;
}
res.header('Cache-Control', 'no-cache,max-age='+ttl+',must-revalidate,public');
}
// Only set an X-Cache-Channel for responses we want Varnish to cache.
if ( tableCacheItem && tableCacheItem.affected_tables.length > 0 && !tableCacheItem.may_write ) {
res.header('X-Cache-Channel', generateCacheKey(dbopts.dbname, tableCacheItem, dbopts.authenticated));
}
var lastModified = (tableCacheItem && tableCacheItem.last_modified) ?
tableCacheItem.last_modified :
Date.now();
res.header('Last-Modified', new Date(lastModified).toUTCString());
return null;
},
function generateFormat(err){
assert.ifError(err);
checkAborted('generateFormat');
// TODO: drop this, fix UI!
sql = new PSQL.QueryWrapper(sql).orderBy(orderBy, sortOrder).window(limit, offset).query();
var opts = {
username: cdbUsername,
dbopts: dbopts,
sink: res,
gn: gn,
dp: dp,
skipfields: skipfields,
sql: sql,
filename: filename,
bufferedRows: global.settings.bufferedRows,
callback: params.callback,
abortChecker: checkAborted
};
if ( req.profiler ) {
opts.profiler = req.profiler;
opts.beforeSink = function() {
req.profiler.done('beforeSink');
res.header('X-SQLAPI-Profiler', req.profiler.toJSONString());
};
}
if (global.settings.api_hostname) {
res.header('X-Served-By-Host', global.settings.api_hostname);
}
if (dbopts.host) {
res.header('X-Served-By-DB-Host', dbopts.host);
}
formatter.sendResponse(opts, this);
},
function errorHandle(err){
formatter = null;
if ( err ) {
handleException(err, res);
}
if ( req.profiler ) {
req.profiler.sendStats(); // TODO: do on nextTick ?
}
if (self.statsd_client) {
if ( err ) {
self.statsd_client.increment('sqlapi.query.error');
} else {
self.statsd_client.increment('sqlapi.query.success');
}
}
}
);
} catch (err) {
handleException(err, res);
if (self.statsd_client) {
self.statsd_client.increment('sqlapi.query.error');
}
}
};
module.exports = QueryController;