feat: query to fetch unique columns

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

Author: aaqilniz

lib/discovery.js

@@ -348,25 +348,17 @@ function mixinDiscovery(PostgreSQL) {
    * @returns {string}
    */
   PostgreSQL.prototype.buildQueryUniqueKeys = function(schema, table) {
-    const sql = `
-        SELECT
-            a.attname AS "columnName",
-            n.nspname AS "owner",
-            c.relname AS "tableName"
-        FROM pg_index i
-        JOIN pg_class c ON c.oid = i.indrelid
-        JOIN pg_namespace n ON n.oid = c.relnamespace
-        JOIN pg_attribute a ON a.attrelid = c.oid AND a.attnum = ANY(i.indkey)
-        WHERE i.indisunique = true
-        AND i.indisprimary = false
-        AND n.nspname = $1
-        AND c.relname = $2
-        ORDER BY a.attnum;
-    `;
-    return {
-        text: sql,
-        values: [schema, table]
-    };
+    const sql = 'SELECT a.attname AS "columnName", n.nspname AS "owner", c.relname AS "tableName"'
+      + 'FROM pg_index i'
+      + 'JOIN pg_class c ON c.oid = i.indrelid'
+      + 'JOIN pg_namespace n ON n.oid = c.relnamespace'
+      + 'JOIN pg_attribute a ON a.attrelid = c.oid AND a.attnum = ANY(i.indkey)'
+      + 'WHERE i.indisunique = true'
+      + 'AND i.indisprimary = false'
+      + 'AND n.nspname = $1'
+      + 'AND c.relname = $2'
+      + 'ORDER BY a.attnum';
+    return {text: sql, values: [schema, table]};
   };
 
   /**

test/postgresql.discover.test.js

@@ -394,6 +394,17 @@ describe('Discover LDL schema from a table', function() {
   });
 });
 
+describe('Discover unique properties', function() {
+  it('should validate unique key for user', function(done) {
+    db.discoverSchema('user', {owner: 'strongloop'}, function(err, schema) {
+      console.log('This is our err: ', err);
+      console.log('This is our schema: ', schema);
+      assert(schema.properties.email.index.unique, true);
+      done(null, schema);
+    });
+  });
+});
+
 describe('Discover and map correctly database types', function() {
   it('should handle character varying, date, timestamp with time zone, timestamp without time zone', function(done) {
     db.discoverSchema('customer', {owner: 'strongloop'}, function(err, schema) {

test/schema.sql

@@ -276,6 +276,7 @@ CREATE TABLE "user" (
     email character varying(100)
 );
 
+ALTER TABLE "user" ADD CONSTRAINT user_email_unique UNIQUE (email);
 --
 -- Name: GeoPoint_id_seq; Type: SEQUENCE; Schema: strongloop; Owner: strongloop
 --