Give access to field names and types independently of rows (brianc#209)

Adds a 'rowDescription' event in query object. Add test for accessing field info via both event and result object
CartoDB · May 30, 2013 · 77f480c · 77f480c
1 parent 30d97e3
commit 77f480c
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Showing 3 changed files with 150 additions and 1 deletion.
diff --git a/lib/query.js b/lib/query.js
@@ -58,12 +58,19 @@ Query.prototype.handleRowDescription = function(msg) {
   this._fieldNames = [];
   this._fieldConverters = [];
   var len = msg.fields.length;
+  var fields = [];
   for(var i = 0; i < len; i++) {
     var field = msg.fields[i];
     var format = field.format;
     this._fieldNames[i] = field.name;
     this._fieldConverters[i] = Types.getTypeParser(field.dataTypeID, format);
+    fields[i] = {
+      name: field.name,
+      type: Types.getTypeName(field.dataTypeID)
+    };
   }
+  this._result.fields = fields;
+  this.emit('rowDescription', fields);
 };
 
 Query.prototype.handleDataRow = function(msg) {

diff --git a/lib/types/index.js b/lib/types/index.js
@@ -11,6 +11,114 @@ var noParse = function(val) {
   return String(val);
 };
 
+// returns a type name for a type oid
+var getTypeName = function(oid) {
+ // extracted with:
+ // select '''' || oid || ''': ' || '''' || typname || ''',' from pg_type where oid < 2048 order by oid;
+  var typeNames = {
+ '16': 'bool',
+ '17': 'bytea',
+ '18': 'char',
+ '19': 'name',
+ '20': 'int8',
+ '21': 'int2',
+ '22': 'int2vector',
+ '23': 'int4',
+ '24': 'regproc',
+ '25': 'text',
+ '26': 'oid',
+ '27': 'tid',
+ '28': 'xid',
+ '29': 'cid',
+ '30': 'oidvector',
+ '71': 'pg_type',
+ '75': 'pg_attribute',
+ '81': 'pg_proc',
+ '83': 'pg_class',
+ '142': 'xml',
+ '143': '_xml',
+ '194': 'pg_node_tree',
+ '210': 'smgr',
+ '600': 'point',
+ '601': 'lseg',
+ '602': 'path',
+ '603': 'box',
+ '604': 'polygon',
+ '628': 'line',
+ '629': '_line',
+ '650': 'cidr',
+ '651': '_cidr',
+ '700': 'float4',
+ '701': 'float8',
+ '702': 'abstime',
+ '703': 'reltime',
+ '704': 'tinterval',
+ '705': 'unknown',
+ '718': 'circle',
+ '719': '_circle',
+ '790': 'money',
+ '791': '_money',
+ '829': 'macaddr',
+ '869': 'inet',
+ '1000': '_bool',
+ '1001': '_bytea',
+ '1002': '_char',
+ '1003': '_name',
+ '1005': '_int2',
+ '1006': '_int2vector',
+ '1007': '_int4',
+ '1008': '_regproc',
+ '1009': '_text',
+ '1010': '_tid',
+ '1011': '_xid',
+ '1012': '_cid',
+ '1013': '_oidvector',
+ '1014': '_bpchar',
+ '1015': '_varchar',
+ '1016': '_int8',
+ '1017': '_point',
+ '1018': '_lseg',
+ '1019': '_path',
+ '1020': '_box',
+ '1021': '_float4',
+ '1022': '_float8',
+ '1023': '_abstime',
+ '1024': '_reltime',
+ '1025': '_tinterval',
+ '1027': '_polygon',
+ '1028': '_oid',
+ '1033': 'aclitem',
+ '1034': '_aclitem',
+ '1040': '_macaddr',
+ '1041': '_inet',
+ '1042': 'bpchar',
+ '1043': 'varchar',
+ '1082': 'date',
+ '1083': 'time',
+ '1114': 'timestamp',
+ '1115': '_timestamp',
+ '1182': '_date',
+ '1183': '_time',
+ '1184': 'timestamptz',
+ '1185': '_timestamptz',
+ '1186': 'interval',
+ '1187': '_interval',
+ '1231': '_numeric',
+ '1248': 'pg_database',
+ '1263': '_cstring',
+ '1266': 'timetz',
+ '1270': '_timetz',
+ '1560': 'bit',
+ '1561': '_bit',
+ '1562': 'varbit',
+ '1563': '_varbit',
+ '1700': 'numeric',
+ '1790': 'refcursor'
+  };
+  if ( typeNames[oid] ) return typeNames[oid];
+  return oid;
+};
+
 //returns a function used to convert a specific type (specified by
 //oid) into a result javascript type
 var getTypeParser = function(oid, format) {
@@ -41,5 +149,6 @@ binaryParsers.init(function(oid, converter) {
 
 module.exports = {
   getTypeParser: getTypeParser,
-  setTypeParser: setTypeParser
+  setTypeParser: setTypeParser,
+  getTypeName: getTypeName
 };
diff --git a/test/integration/client/api-tests.js b/test/integration/client/api-tests.js
@@ -165,3 +165,36 @@ test('null and undefined are both inserted as NULL', function() {
     }))
   }))
 })
+
+test('provides field names and types to the callback', function() {
+  pg.connect(helper.config, assert.calls(function(err, client, done) {
+    assert.isNull(err);
+    var config = {
+      text: 'select $1::text as val limit 0'
+    };
+    client.query(config, ['hi'], assert.calls(function(err, result) {
+      assert.isNull(err);
+      assert.equal(result.fields.length, 1);
+      assert.equal(result.fields[0].name, 'val');
+      assert.equal(result.fields[0].type, 'text');
+      done();
+    }))
+  }))
+})
+
+test('provides field names and types to the rowDescription event', function() {
+  pg.connect(helper.config, assert.calls(function(err, client, done) {
+    assert.isNull(err);
+    var config = {
+      text: 'select $1::text as val limit 1'
+    };
+    var query = client.query(config, ['hi']);
+    assert.emits(query, 'rowDescription', function(fields) {
+      assert.equal(fields.length, 1);
+      assert.equal(fields[0].name, 'val');
+      assert.equal(fields[0].type, 'text');
+      done();
+    })
+  }))
+})
+