fix: add generated property to model properties

Signed-off-by: Muhammad Aaqil <[email protected]>

lib/discovery.js

@@ -135,6 +135,13 @@ function mixinDiscovery(PostgreSQL) {
         cb(err, results);
       } else {
         results.map(function(r) {
+          // PostgreSQL returns ALWAYS in case the property is generated,
+          // otherwise it returns NEVER
+          if (r.generated === 'ALWAYS') {
+            r.generated = true;
+          } else {
+            r.generated = false;
+          }
           // PostgreSQL accepts float(1) to float(24) as selecting the `real` type,
           // while float(25) to float(53) select `double precision`
           // https://www.postgresql.org/docs/9.4/static/datatype-numeric.html
@@ -166,6 +173,7 @@ function mixinDiscovery(PostgreSQL) {
     if (owner) {
       sql = this.paginateSQL('SELECT table_schema AS "owner", table_name AS "tableName", column_name AS "columnName",'
           + 'data_type AS "dataType", character_maximum_length AS "dataLength", numeric_precision AS "dataPrecision",'
+          + ' is_generated AS "generated",'
           + ' numeric_scale AS "dataScale", is_nullable AS "nullable"'
           + ' FROM information_schema.columns'
           + ' WHERE table_schema=\'' + owner + '\''
@@ -175,6 +183,7 @@ function mixinDiscovery(PostgreSQL) {
       sql = this.paginateSQL('SELECT current_schema() AS "owner", table_name AS "tableName",'
           + ' column_name AS "columnName",'
           + ' data_type AS "dataType", character_maximum_length AS "dataLength", numeric_precision AS "dataPrecision",'
+          + ' is_generated AS "generated",'
           + ' numeric_scale AS "dataScale", is_nullable AS "nullable"'
           + ' FROM information_schema.columns'
           + (table ? ' WHERE table_name=\'' + table + '\'' : ''),

test/postgresql.discover.test.js

@@ -408,6 +408,25 @@ describe('Discover and map correctly database types', function() {
   });
 });
 
+describe('Discover model with generated property', function() {
+  it('should handle generated column', function(done) {
+    db.discoverSchema('inventory', {owner: 'strongloop'}, function(err, schema) {
+      if (err) {
+        console.error(err);
+        done(err);
+      } else {
+        assert(schema.options.postgresql.schema === 'strongloop');
+        assert(schema.options.postgresql.table === 'inventory');
+        assert(schema.properties.token);
+        assert(schema.properties.token.generated === true);
+        assert(schema.properties.productId);
+        assert(schema.properties.productId.generated === false);
+        done();
+      }
+    });
+  });
+});
+
 describe('Discover and build models', function() {
   it('should build a model from discovery', function(done) {
     db.discoverAndBuildModels('GeoPoint', {schema: 'strongloop'}, function(err, schema) {

test/schema.sql

@@ -319,7 +319,8 @@ CREATE TABLE inventory (
     product_id character varying(20),
     location_id character varying(20),
     available integer,
-    total integer
+    total integer,
+    token integer GENERATED ALWAYS AS (total * 1000) STORED,
 );