From 6b61bcf1230470094bc25b5b4354f1e805d45daa Mon Sep 17 00:00:00 2001
From: Naz <nazargargol@gmail.com>
Date: Thu, 4 Feb 2021 13:17:50 +1300
Subject: [PATCH] Added unique constraint notation to schema definition

refs https://github.com/TryGhost/Ghost/issues/12567

- Introduced here @@UNIQUE_CONSTRAINTS@@ notation allows to create unique contraints over multiple database fields. This will be needed to change posts' table unique constraint from `slug` to `slug+type`.
- The notation is equivalent to SQL's: UNIQUE(column_name1,column_name2)
- Example use in schema:
posts: {
    slug: {type: 'string', maxlength: 191, nullable: false},
    type: {type: 'string', maxlength: 50, nullable: false, defaultTo: 'post', validations: {isIn: [['post', 'page']]}},
    '@@UNIQUES@@': [
        ['slug', 'type']
    ]
}
---
 core/server/data/schema/commands.js | 10 ++++++++++
 core/server/models/base/index.js    |  3 ++-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/core/server/data/schema/commands.js b/core/server/data/schema/commands.js
index d5a1eb79a7..34bfacca1c 100644
--- a/core/server/data/schema/commands.js
+++ b/core/server/data/schema/commands.js
@@ -104,6 +104,7 @@ function createTable(table, transaction, tableSpec = schema[table]) {
 
             return (transaction || db.knex).schema.createTable(table, function (t) {
                 let tableIndexes = [];
+                let tableUniqueConstraints = [];
 
                 const columnKeys = _.keys(tableSpec);
                 _.each(columnKeys, function (column) {
@@ -112,12 +113,21 @@ function createTable(table, transaction, tableSpec = schema[table]) {
                         return;
                     }
 
+                    if (column === '@@UNIQUE_CONSTRAINTS@@') {
+                        tableUniqueConstraints = tableSpec['@@UNIQUE_CONSTRAINTS@@'];
+                        return;
+                    }
+
                     return addTableColumn(table, t, column, tableSpec[column]);
                 });
 
                 _.each(tableIndexes, function (index) {
                     t.index(index);
                 });
+
+                _.each(tableUniqueConstraints, function (unique) {
+                    t.unique(unique);
+                });
             });
         });
 }
diff --git a/core/server/models/base/index.js b/core/server/models/base/index.js
index 7949696c52..bfdff17ab6 100644
--- a/core/server/models/base/index.js
+++ b/core/server/models/base/index.js
@@ -1254,7 +1254,8 @@ ghostBookshelf.Model = ghostBookshelf.Model.extend({
 
             // exclude fields if enabled
             if (exclude) {
-                const toSelect = _.keys(schema.tables[tableNames[modelName]]);
+                let toSelect = _.keys(schema.tables[tableNames[modelName]]);
+                toSelect = toSelect.filter(key => !(key.startsWith('@@')));
 
                 _.each(exclude, (key) => {
                     if (toSelect.indexOf(key) !== -1) {