Allow explicit numeric datatype

lib/migration.js

@@ -387,6 +387,33 @@ function mixinMigration(PostgreSQL) {
     return colDefault ? (' DEFAULT ' + colDefault) : '';
   };
 
+  // override this function from base connector to allow postgres connector to
+  // accept dataPrecision and dataScale as column specific properties
+  PostgreSQL.prototype.columnDataType = function(model, property) {
+    var columnMetadata = this.columnMetadata(model, property);
+    var colType = columnMetadata && columnMetadata.dataType;
+    if (colType) {
+      colType = colType.toUpperCase();
+    }
+    var prop = this.getModelDefinition(model).properties[property];
+    if (!prop) {
+      return null;
+    }
+    var colLength = columnMetadata && columnMetadata.dataLength || prop.length || prop.limit;
+    var colPrecision = columnMetadata && columnMetadata.dataPrecision;
+    var colScale = columnMetadata && columnMetadata.dataScale;
+    // info on setting column specific properties
+    // i.e dataLength, dataPrecision, dataScale
+    // https://loopback.io/doc/en/lb3/Model-definition-JSON-file.html
+    if (colType) {
+      if (colLength) return colType + '(' + colLength + ')';
+      if (colPrecision && colScale) return colType + '(' + colPrecision + ',' + colScale + ')';
+      if (colPrecision) return colType + '(' + colPrecision + ')';
+      return colType;
+    }
+    return this.buildColumnType(prop);
+  };
+
   PostgreSQL.prototype.buildColumnType = function buildColumnType(propertyDefinition) {
     var p = propertyDefinition;
     switch (p.type.name) {

test/postgresql.test.js

@@ -13,7 +13,7 @@ require('./init');
 var async = require('async');
 var should = require('should');
 
-var Post, db, created;
+var Post, Expense, db, created;
 
 describe('lazyConnect', function() {
   it('should skip connect phase (lazyConnect = true)', function(done) {
@@ -69,6 +69,68 @@ describe('postgresql connector', function() {
     created = new Date();
   });
 
+  describe('Explicit datatype', function() {
+    before(function(done) {
+      db = getDataSource();
+
+      Expense = db.define('Expense', {
+        id: {
+          type: Number,
+          id: true,
+          required: true,
+          postgresql: {
+            dataType: 'NUMERIC',
+            dataPrecision: 3,
+          },
+        },
+        description: {
+          type: String,
+        },
+        amount: {
+          type: Number,
+          required: true,
+          postgresql: {
+            dataType: 'DECIMAL',
+            dataPrecision: 10,
+            dataScale: 2,
+          },
+        },
+      });
+      db.automigrate(done);
+    });
+
+    it('create instance with explicit datatype', function(done) {
+      Expense.create(data, function(err, result) {
+        should.not.exist(err);
+        should.exist(result);
+        should.equal(result.length, data.length);
+        done();
+      });
+    });
+
+    it('find instance with a decimal datatype', function(done) {
+      Expense.find({where: {amount: 159.99}}, function(err, result) {
+        should.not.exist(err);
+        should.exist(result);
+        should.equal(result.length, 1);
+        // need to parseFloat the amount value since it is returned as a string
+        // because loopback does not have a known "decimal" datatype
+        should.deepEqual(parseFloat(result[0].__data.amount), data[0].amount);
+        done();
+      });
+    });
+
+    it('find instance with a numeric datatype', function(done) {
+      Expense.find({where: {id: 258}}, function(err, result) {
+        should.not.exist(err);
+        should.exist(result);
+        should.equal(result.length, 1);
+        should.deepEqual(parseInt(result[0].__data.id), data[2].id);
+        done();
+      });
+    });
+  });
+
   it('should run migration', function(done) {
     db.automigrate('PostWithBoolean', function() {
       done();
@@ -562,6 +624,24 @@ describe('Serial properties', function() {
   });
 });
 
+var data = [
+  {
+    id: 1,
+    description: 'Expense 1',
+    amount: 159.99,
+  },
+  {
+    id: 200,
+    description: 'Expense 2',
+    amount: 10,
+  },
+  {
+    id: 258,
+    description: 'Expense 3',
+    amount: 12.49,
+  },
+];
+
 // FIXME: The following test cases are to be reactivated for PostgreSQL
 /*