Allow using GET with sql-api for queries shorter than configured len

Introduces new sqlapi.max_get_sql_length directive, defaults to 2048.
Closes #155
Includes testcases.

NEWS.md

@@ -5,6 +5,8 @@ Enhancements:
 
  * Allow using ":host" as part of statsd.prefix (#153)
  * Expand "addCacheChannel" stats
+ * Allow using GET with sql-api for queries shorter than configured len (#155)
+   [ new sqlapi.max_get_sql_length directive, defaults to 2048 ]
 
 Bug fixes:
 

config/environments/development.js.example

@@ -102,7 +102,11 @@ var config = {
         // the cartodb username and passed to
         // SQL-API requests in the Host HTTP header
         domain: 'localhost.lan',
-        version: 'v1'
+        version: 'v1',
+        // Maximum lenght of SQL query for GET
+        // requests. Longer queries will be sent
+        // using POST. Defaults to 2048
+        max_get_sql_length: 2048
     }
     ,varnish: {
         host: 'localhost',

config/environments/production.js.example

@@ -96,7 +96,11 @@ var config = {
         // the cartodb username and passed to
         // SQL-API requests in the Host HTTP header
         domain: 'cartodb.com',
-        version: 'v2'
+        version: 'v2',
+        // Maximum lenght of SQL query for GET
+        // requests. Longer queries will be sent
+        // using POST. Defaults to 2048
+        max_get_sql_length: 2048
     }
     ,varnish: {
         host: 'localhost',

config/environments/staging.js.example

@@ -96,7 +96,11 @@ var config = {
         // the cartodb username and passed to
         // SQL-API requests in the Host HTTP header
         domain: 'cartodb.com',
-        version: 'v2'
+        version: 'v2',
+        // Maximum lenght of SQL query for GET
+        // requests. Longer queries will be sent
+        // using POST. Defaults to 2048
+        max_get_sql_length: 2048
     }
     ,varnish: {
         host: 'localhost',

config/environments/test.js.example

@@ -98,7 +98,11 @@ var config = {
         domain: 'donot_look_this_up',
         // This port will be used by "make check" for testing purposes
         // It must be available
-        version: 'v1'
+        version: 'v1',
+        // Maximum lenght of SQL query for GET
+        // requests. Longer queries will be sent
+        // using POST. Defaults to 2048
+        max_get_sql_length: 2048
     }
     ,varnish: {
         host: '',

lib/cartodb/server_options.js

@@ -115,14 +115,23 @@ module.exports = function(){
       // See http://nodejs.org/api/http.html#http_agent_maxsockets
       //
       var maxSockets = global.environment.maxConnections || 128;
-      request.post({
-          url:sqlapi, body:qs, json:true,
-          headers:{host: sqlapihostname}
-          // http://nodejs.org/api/http.html#http_agent_maxsockets
-          ,pool:{maxSockets:maxSockets}
-          //,timeout:100
-        }, function(err, res, body)
-      {
+      var maxGetLen = api.max_get_sql_length || 2048;
+      var reqSpec = {
+            url:sqlapi,
+            json:true,
+            headers:{host: sqlapihostname}
+            // http://nodejs.org/api/http.html#http_agent_maxsockets
+            ,pool:{maxSockets:maxSockets}
+            //,timeout:100
+      }
+      if ( sql.length > maxGetLen ) {
+        reqSpec.method = 'POST';
+        reqSpec.body = qs;
+      } else {
+        reqSpec.method = 'GET';
+        reqSpec.qs = qs;
+      }
+      request(reqSpec, function(err, res, body) {
           if (err){
             console.log('ERROR connecting to SQL API on ' + sqlapi + ': ' + err);
             callback(err);

test/acceptance/multilayer.js

@@ -1059,10 +1059,12 @@ suite('multilayer', function() {
           var parsedBody = JSON.parse(res.body);
           var token_components = parsedBody.layergroupid.split(':');
           expected_token = token_components[0];
+          var last_request = sqlapi_server.getLastRequest();
+          assert.equal(last_request.method, 'POST');
           return null;
         },
         function cleanup(err) {
-          if ( err ) errors.push(err.message);
+          if ( err ) errors.push('' + err);
           if ( ! expected_token ) return null;
           var next = this;
           redis_client.keys("map_cfg|" + expected_token, function(err, matches) {

test/acceptance/server.js

@@ -1148,6 +1148,7 @@ suite('server', function() {
             assert.ok(last_request);
             var host = last_request.headers['host'];
             assert.ok(host);
+            assert.equal(last_request.method, 'GET');
             assert.equal(host, 'localhost.donot_look_this_up');
             return null;
           },