Added basic post creation.

migrations/20230513004141_init.js

@@ -1,4 +1,16 @@
-exports.up = async function(knex) {
+import fs from 'fs';
+
+export async function up(knex) {
+	const nanoidFn = await fs.promises.readFile('./migrations/nanoid.sql', 'utf8'); // from https://github.com/viascom/nanoid-postgres
+
+	await knex.raw(nanoidFn);
+
+	await knex.raw(`
+		CREATE FUNCTION shack_id(length smallint DEFAULT 8) RETURNS TEXT AS $$
+			SELECT nanoid(length, '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz');
+		$$ LANGUAGE SQL STABLE;
+	`);
+
 	await knex.schema.createTable('users', (table) => {
 		table.increments('id');
 
@@ -63,7 +75,9 @@ exports.up = async function(knex) {
 	});
 
 	await knex.schema.createTable('posts', (table) => {
-		table.increments('id');
+		table.text('id', 8)
+			.primary()
+			.defaultTo(knex.raw('shack_id()'));
 
 		table.text('title')
 			.notNullable();
@@ -86,12 +100,39 @@ exports.up = async function(knex) {
 			.defaultTo(knex.fn.now());
 	});
 
-	await knex.raw(`ALTER TABLE posts ADD CONSTRAINT post_content CHECK (body IS NOT NULL OR url IS NOT NULL)`);
-};
+	await knex.raw('ALTER TABLE posts ADD CONSTRAINT post_content CHECK (body IS NOT NULL OR url IS NOT NULL)');
 
-exports.down = async function(knex) {
+	await knex.schema.createTable('comments', (table) => {
+		table.text('id', 8)
+			.primary()
+			.defaultTo(knex.raw('shack_id()'));
+
+		table.text('post_id', 8)
+			.notNullable()
+			.references('id')
+			.inTable('posts');
+
+		table.integer('user_id')
+			.notNullable()
+			.references('id')
+			.inTable('users');
+
+		table.text('body');
+
+		table.datetime('created_at')
+			.notNullable()
+			.defaultTo(knex.fn.now());
+	});
+}
+
+export async function down(knex) {
+	await knex.schema.dropTable('comments');
 	await knex.schema.dropTable('posts');
 	await knex.schema.dropTable('shelves_settings');
 	await knex.schema.dropTable('shelves');
 	await knex.schema.dropTable('users');
-};
+
+	await knex.raw(`
+		DROP FUNCTION IF EXISTS shack_id;
+	`);
+}

migrations/nanoid.sql

@@ -0,0 +1,66 @@
+/*
+ * Copyright 2023 Viascom Ltd liab. Co
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+CREATE EXTENSION IF NOT EXISTS pgcrypto;
+
+CREATE OR REPLACE FUNCTION nanoid(
+    size int DEFAULT 21,
+    alphabet text DEFAULT '_-0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'
+)
+    RETURNS text
+    LANGUAGE plpgsql
+    volatile
+AS
+$$
+DECLARE
+    idBuilder      text := '';
+    counter        int  := 0;
+    bytes          bytea;
+    alphabetIndex  int;
+    alphabetArray  text[];
+    alphabetLength int;
+    mask           int;
+    step           int;
+BEGIN
+    alphabetArray := regexp_split_to_array(alphabet, '');
+    alphabetLength := array_length(alphabetArray, 1);
+    mask := (2 << cast(floor(log(alphabetLength - 1) / log(2)) as int)) - 1;
+    step := cast(ceil(1.6 * mask * size / alphabetLength) AS int);
+
+    while true
+        loop
+            bytes := gen_random_bytes(step);
+            while counter < step
+                loop
+                    alphabetIndex := (get_byte(bytes, counter) & mask) + 1;
+                    if alphabetIndex <= alphabetLength then
+                        idBuilder := idBuilder || alphabetArray[alphabetIndex];
+                        if length(idBuilder) = size then
+                            return idBuilder;
+                        end if;
+                    end if;
+                    counter := counter + 1;
+                end loop;
+
+            counter := 0;
+        end loop;
+END
+$$;