Restore object structure after select with join

lib/pg.cursor.js

@@ -5,6 +5,7 @@ const { extractDecorator } = require('metaschema');
 const transformations = require('./transformations');
 const { SelectBuilder } = require('./sqlgen');
 const { Cursor } = require('./cursor');
+const { expand } = require('./pg.utils');
 
 const jsqlToSQLConverters = {
   select: (op, query) => {
@@ -57,11 +58,13 @@ class PostgresCursor extends Cursor {
       .categories.get(this.category)
       .definition;
 
+    let needsExpanding = false;
     for (const key in schema) {
       const field = schema[key];
       if (extractDecorator(field) === 'Include') {
         const cat = field.category;
         pgquery.innerJoin(cat, `${this.category}.Id`, `${cat}.Id`);
+        needsExpanding = true;
       }
     }
 
@@ -71,8 +74,11 @@ class PostgresCursor extends Cursor {
         return;
       }
       this.jsql = this.jsql.slice(i);
-      if (this.jsql.length === 0) callback(null, res.rows, this);
-      else this.continue(res.rows, callback);
+      const rows = needsExpanding ?
+        res.rows.map(row => expand(row, schema)) : res.rows;
+
+      if (this.jsql.length === 0) callback(null, rows, this);
+      else this.continue(rows, callback);
     });
   }
 }

lib/pg.utils.js

@@ -1,6 +1,7 @@
 'use strict';
 
 const transformations = require('./transformations');
+const { extractDecorator } = require('metaschema');
 
 const escapeString = value => {
   let backslash = false;
@@ -136,6 +137,23 @@ const buildWhere = query => {
   }).join(' AND '), params];
 };
 
+const expand = (object, schema) => {
+  const result = {};
+  if (object.Id) {
+    result.Id = object.Id;
+  }
+  for (const prop in schema) {
+    const field = schema[prop];
+    const value = object[prop];
+    if (value !== undefined) {
+      result[prop] = value;
+    } else if (extractDecorator(field) === 'Include') {
+      result[prop] = expand(object, field.definition);
+    }
+  }
+  return result;
+};
+
 module.exports = {
   escapeString,
   escapeValue,
@@ -147,4 +165,5 @@ module.exports = {
   generateQueryParams,
   buildWhere,
   classMapping,
+  expand,
 };

test/pg.js

@@ -218,6 +218,6 @@ prepareDB(err => {
           }
         );
       });
-    }, { todo: true });
+    });
   });
 });