Advanced pgTAP Testing

While basic pgTAP provides excellent testing capabilities, you can enhance the testing workflow using database development tools and helper packages. This guide covers advanced testing techniques using database.dev and community-maintained test helpers.

Using database.dev

Database.dev is a package manager for Postgres that allows installation and use of community-maintained packages, including testing utilities.

Setting up dbdev

To use database development tools and packages, install some prerequisites:

sql

create extension if not exists http with schema extensions;
create extension if not exists pg_tle;
drop extension if exists "supabase-dbdev";
select pgtle.uninstall_extension_if_exists('supabase-dbdev');
select
    pgtle.install_extension(
        'supabase-dbdev',
        resp.contents ->> 'version',
        'PostgreSQL package manager',
        resp.contents ->> 'sql'
    )
from extensions.http(
    (
        'GET',
        'https://api.database.dev/rest/v1/'
        || 'package_versions?select=sql,version'
        || '&package_name=eq.supabase-dbdev'
        || '&order=version.desc'
        || '&limit=1',
        array[
            ('apiKey', 'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJzdXBhYmFzZSIsInJlZiI6InhtdXB0cHBsZnZpaWZyYndtbXR2Iiwicm9sZSI6ImFub24iLCJpYXQiOjE2ODAxMDczNzIsImV4cCI6MTk5NTY4MzM3Mn0.z2CN0mvO2No8wSi46Gw59DFGCTJrzM0AQKsu_5k134s')::extensions.http_header
        ],
        null,
        null
    )
) x,
lateral (
    select
        ((row_to_json(x) -> 'content') #>> '{}')::json -> 0
) resp(contents);
create extension "supabase-dbdev";
select dbdev.install('supabase-dbdev');

-- Drop and recreate the extension to ensure a clean installation
drop extension if exists "supabase-dbdev";
create extension "supabase-dbdev";

Installing test helpers

The Test Helpers package provides utilities that simplify testing Supabase-specific features:

sql

select dbdev.install('basejump-supabase_test_helpers');
create extension if not exists "basejump-supabase_test_helpers" version '0.0.6';

Test helper benefits

The test helpers package provides several advantages over writing raw pgTAP tests:

Simplified User Management
- Create test users with tests.create_supabase_user()
- Switch contexts with tests.authenticate_as()
- Retrieve user IDs using tests.get_supabase_uid()
Row Level Security (RLS) Testing Utilities
- Verify RLS status with tests.rls_enabled()
- Test policy enforcement
- Simulate different user contexts
Reduced Boilerplate
- No need to manually insert auth.users
- Simplified JWT claim management
- Clean test setup and cleanup

Schema-wide Row Level Security testing

When working with Row Level Security, it's crucial to ensure that RLS is enabled on all tables that need it. Create a simple test to verify RLS is enabled across an entire schema:

sql

begin;
select plan(1);

-- Verify RLS is enabled on all tables in the public schema
select tests.rls_enabled('public');

select * from finish();
rollback;

Test file organization

When working with multiple test files that share common setup requirements, it's beneficial to create a single "pre-test" file that handles the global environment setup. This approach reduces duplication and ensures consistent test environments.

Creating a pre-test hook

Since pgTAP test files are executed in alphabetical order, create a setup file that runs first by using a naming convention like 000-setup-tests-hooks.sql:

bash

supabase test new 000-setup-tests-hooks

This setup file should contain:

All shared extensions and dependencies
Common test utilities
A simple always green test to verify the setup

Here's an example setup file:

sql

-- install tests utilities
-- install pgtap extension for testing
create extension if not exists pgtap with schema extensions;
/*
---------------------
---- install dbdev ----
----------------------
Requires:
  - pg_tle: https://github.com/aws/pg_tle
  - pgsql-http: https://github.com/pramsey/pgsql-http
*/
create extension if not exists http with schema extensions;
create extension if not exists pg_tle;
drop extension if exists "supabase-dbdev";
select pgtle.uninstall_extension_if_exists('supabase-dbdev');
select
    pgtle.install_extension(
        'supabase-dbdev',
        resp.contents ->> 'version',
        'PostgreSQL package manager',
        resp.contents ->> 'sql'
    )
from extensions.http(
    (
        'GET',
        'https://api.database.dev/rest/v1/'
        || 'package_versions?select=sql,version'
        || '&package_name=eq.supabase-dbdev'
        || '&order=version.desc'
        || '&limit=1',
        array[
            ('apiKey', 'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJzdXBhYmFzZSIsInJlZiI6InhtdXB0cHBsZnZpaWZyYndtbXR2Iiwicm9sZSI6ImFub24iLCJpYXQiOjE2ODAxMDczNzIsImV4cCI6MTk5NTY4MzM3Mn0.z2CN0mvO2No8wSi46Gw59DFGCTJrzM0AQKsu_5k134s')::extensions.http_header
        ],
        null,
        null
    )
) x,
lateral (
    select
        ((row_to_json(x) -> 'content') #>> '{}')::json -> 0
) resp(contents);
create extension "supabase-dbdev";
select dbdev.install('supabase-dbdev');
drop extension if exists "supabase-dbdev";
create extension "supabase-dbdev";
-- Install test helpers
select dbdev.install('basejump-supabase_test_helpers');
create extension if not exists "basejump-supabase_test_helpers" version '0.0.6';

-- Verify setup with a no-op test
begin;
select plan(1);
select ok(true, 'Pre-test hook completed successfully');
select * from finish();
rollback;

Benefits

This approach provides several advantages:

Reduces code duplication across test files
Ensures consistent test environment setup
Makes it easier to maintain and update shared dependencies
Provides immediate feedback if the setup process fails

Your subsequent test files (001-auth-tests.sql, 002-rls-tests.sql) can focus solely on their specific test cases, knowing that the environment is properly configured.

Example: Advanced RLS testing

Here's a complete example using test helpers to verify RLS policies putting it all together:

sql

begin;
-- Assuming 000-setup-tests-hooks.sql file is present to use tests helpers
select plan(4);

-- Set up test data

-- Create test supabase users
select tests.create_supabase_user('[email protected]');
select tests.create_supabase_user('[email protected]');

-- Create test data
insert into public.todos (task, user_id) values
  ('User 1 Task 1', tests.get_supabase_uid('[email protected]')),
  ('User 1 Task 2', tests.get_supabase_uid('[email protected]')),
  ('User 2 Task 1', tests.get_supabase_uid('[email protected]'));

-- Test as User 1
select tests.authenticate_as('[email protected]');

-- Test 1: User 1 should only see their own todos
select results_eq(
  'select count(*) from todos',
  ARRAY[2::bigint],
  'User 1 should only see their 2 todos'
);

-- Test 2: User 1 can create their own todo
select lives_ok(
  $$insert into todos (task, user_id) values ('New Task', tests.get_supabase_uid('[email protected]'))$$,
  'User 1 can create their own todo'
);

-- Test as User 2
select tests.authenticate_as('[email protected]');

-- Test 3: User 2 should only see their own todos
select results_eq(
  'select count(*) from todos',
  ARRAY[1::bigint],
  'User 2 should only see their 1 todo'
);

-- Test 4: User 2 cannot modify User 1's todo
SELECT results_ne(
    $$ update todos set task = 'Hacked!' where user_id = tests.get_supabase_uid('[email protected]') returning 1 $$,
    $$ values(1) $$,
    'User 2 cannot modify User 1 todos'
);

select * from finish();
rollback;

Not another todo app: Testing complex organizations

Todo apps are great for learning, but this section explores testing a more realistic scenario: a multi-tenant content publishing platform. This example demonstrates testing complex permissions, plan restrictions, and content management.

System overview

This demo app implements:

Organizations with tiered plans (free/pro/enterprise)
Role-based access (owner/admin/editor/viewer)
Content management (posts/comments)
Premium content restrictions
Plan-based limitations

What makes this complex?

Layered Permissions
- Role hierarchies affect access rights
- Plan types influence user capabilities
- Content state (draft/published) affects permissions
Business Rules
- Free plan post limits
- Premium content visibility
- Cross-organization security

Testing focus areas

When writing tests, verify:

Organization member access control
Content visibility across roles
Plan limitation enforcement
Cross-organization data isolation

1. App schema definitions

The app schema tables are defined like this:

sql

create table public.profiles (
  id uuid references auth.users(id) primary key,
  username text unique not null,
  full_name text,
  bio text,
  created_at timestamptz default now(),
  updated_at timestamptz default now()
);

create table public.organizations (
  id bigint primary key generated always as identity,
  name text not null,
  slug text unique not null,
  plan_type text not null check (plan_type in ('free', 'pro', 'enterprise')),
  max_posts int not null default 5,
  created_at timestamptz default now()
);

create table public.org_members (
  org_id bigint references public.organizations(id) on delete cascade,
  user_id uuid references auth.users(id) on delete cascade,
  role text not null check (role in ('owner', 'admin', 'editor', 'viewer')),
  created_at timestamptz default now(),
  primary key (org_id, user_id)
);

create table public.posts (
  id bigint primary key generated always as identity,
  title text not null,
  content text not null,
  author_id uuid references public.profiles(id) not null,
  org_id bigint references public.organizations(id),
  status text not null check (status in ('draft', 'published', 'archived')),
  is_premium boolean default false,
  scheduled_for timestamptz,
  category text,
  view_count int default 0,
  published_at timestamptz,
  created_at timestamptz default now(),
  updated_at timestamptz default now()
);

create table public.comments (
  id bigint primary key generated always as identity,
  post_id bigint references public.posts(id) on delete cascade,
  author_id uuid references public.profiles(id),
  content text not null,
  is_deleted boolean default false,
  created_at timestamptz default now(),
  updated_at timestamptz default now()
);

2. RLS policies declaration

Now to setup the RLS policies for each tables:

sql

-- Create a private schema to store all security definer functions utils
-- As such functions should never be in an API exposed schema
create schema if not exists private;
-- Helper function for role checks
create or replace function private.get_user_org_role(org_id bigint, user_id uuid)
returns text
set search_path = ''
as $$
  select role from public.org_members
  where org_id = $1 and user_id = $2;
-- Note the use of security definer to avoid RLS checking recursion issue
-- see: https://supabase.com/docs/guides/database/postgres/row-level-security#use-security-definer-functions
$$ language sql security definer;
-- Helper utils to check if an org is below the max post limit
create or replace function private.can_add_post(org_id bigint)
returns boolean
set search_path = ''
as $$
  select (select count(*)
          from public.posts p
          where p.org_id = $1) < o.max_posts
  from public.organizations o
  where o.id = $1
$$ language sql security definer;


-- Enable RLS for all tables
alter table public.profiles enable row level security;
alter table public.organizations enable row level security;
alter table public.org_members enable row level security;
alter table public.posts enable row level security;
alter table public.comments enable row level security;

-- Profiles policies
create policy "Public profiles are viewable by everyone"
  on public.profiles for select using (true);

create policy "Users can insert their own profile"
  on public.profiles for insert with check ((select auth.uid()) = id);

create policy "Users can update their own profile"
  on public.profiles for update using ((select auth.uid()) = id)
  with check ((select auth.uid()) = id);

-- Organizations policies
create policy "Public org info visible to all"
  on public.organizations for select using (true);

create policy "Org management restricted to owners"
  on public.organizations for all using (
    private.get_user_org_role(id, (select auth.uid())) = 'owner'
  );

-- Org Members policies
create policy "Members visible to org members"
  on public.org_members for select using (
    private.get_user_org_role(org_id, (select auth.uid())) is not null
  );

create policy "Member management restricted to admins and owners"
  on public.org_members for all using (
    private.get_user_org_role(org_id, (select auth.uid())) in ('owner', 'admin')
  );

-- Posts policies
create policy "Complex post visibility"
  on public.posts for select using (
    -- Published non-premium posts are visible to all
    (status = 'published' and not is_premium)
    or
    -- Premium posts visible to org members only
    (status = 'published' and is_premium and
    private.get_user_org_role(org_id, (select auth.uid())) is not null)
    or
    -- All posts visible to editors and above
    private.get_user_org_role(org_id, (select auth.uid())) in ('owner', 'admin', 'editor')
  );

create policy "Post creation rules"
  on public.posts for insert with check (
    -- Must be org member with appropriate role
    private.get_user_org_role(org_id, (select auth.uid())) in ('owner', 'admin', 'editor')
    and
    -- Check org post limits for free plans
    (
      (select o.plan_type != 'free'
      from organizations o
      where o.id = org_id)
      or
      (select private.can_add_post(org_id))
    )
  );

create policy "Post update rules"
  on public.posts for update using (
    exists (
      select 1
      where
        -- Editors can update non-published posts
        (private.get_user_org_role(org_id, (select auth.uid())) = 'editor' and status != 'published')
        or
        -- Admins and owners can update any post
        private.get_user_org_role(org_id, (select auth.uid())) in ('owner', 'admin')
    )
  );

-- Comments policies
create policy "Comments on published posts are viewable by everyone"
  on public.comments for select using (
    exists (
      select 1 from public.posts
      where id = post_id
      and status = 'published'
    )
    and not is_deleted
  );

create policy "Authenticated users can create comments"
  on public.comments for insert with check ((select auth.uid()) = author_id);

create policy "Users can update their own comments"
  on public.comments for update using (author_id = (select auth.uid()));

3. Test cases:

Now everything is setup, let's write RLS test cases, note that each section could be in its own test:

sql

-- Assuming we already have: 000-setup-tests-hooks.sql file we can use tests helpers
begin;
-- Declare total number of tests
select plan(10);

-- Create test users
select tests.create_supabase_user('org_owner', '[email protected]');
select tests.create_supabase_user('org_admin', '[email protected]');
select tests.create_supabase_user('org_editor', '[email protected]');
select tests.create_supabase_user('premium_user', '[email protected]');
select tests.create_supabase_user('free_user', '[email protected]');
select tests.create_supabase_user('scheduler', '[email protected]');
select tests.create_supabase_user('free_author', '[email protected]');

-- Create profiles for test users
insert into profiles (id, username, full_name)
values
  (tests.get_supabase_uid('org_owner'), 'org_owner', 'Organization Owner'),
  (tests.get_supabase_uid('org_admin'), 'org_admin', 'Organization Admin'),
  (tests.get_supabase_uid('org_editor'), 'org_editor', 'Organization Editor'),
  (tests.get_supabase_uid('premium_user'), 'premium_user', 'Premium User'),
  (tests.get_supabase_uid('free_user'), 'free_user', 'Free User'),
  (tests.get_supabase_uid('scheduler'), 'scheduler', 'Scheduler User'),
  (tests.get_supabase_uid('free_author'), 'free_author', 'Free Author');

-- First authenticate as service role to bypass RLS for initial setup
select tests.authenticate_as_service_role();

-- Create test organizations and setup data
with new_org as (
  insert into organizations (name, slug, plan_type, max_posts)
  values
    ('Test Org', 'test-org', 'pro', 100),
    ('Premium Org', 'premium-org', 'enterprise', 1000),
    ('Schedule Org', 'schedule-org', 'pro', 100),
    ('Free Org', 'free-org', 'free', 2)
  returning id, slug
),
-- Setup members and posts
member_setup as (
  insert into org_members (org_id, user_id, role)
  select
    org.id,
    user_id,
    role
  from new_org org cross join (
    values
      (tests.get_supabase_uid('org_owner'), 'owner'),
      (tests.get_supabase_uid('org_admin'), 'admin'),
      (tests.get_supabase_uid('org_editor'), 'editor'),
      (tests.get_supabase_uid('premium_user'), 'viewer'),
      (tests.get_supabase_uid('scheduler'), 'editor'),
      (tests.get_supabase_uid('free_author'), 'editor')
  ) as members(user_id, role)
  where org.slug = 'test-org'
     or (org.slug = 'premium-org' and role = 'viewer')
     or (org.slug = 'schedule-org' and role = 'editor')
     or (org.slug = 'free-org' and role = 'editor')
)
-- Setup initial posts
insert into posts (title, content, org_id, author_id, status, is_premium, scheduled_for)
select
  title,
  content,
  org.id,
  author_id,
  status,
  is_premium,
  scheduled_for
from new_org org cross join (
  values
    ('Premium Post', 'Premium content', tests.get_supabase_uid('premium_user'), 'published', true, null),
    ('Free Post', 'Free content', tests.get_supabase_uid('premium_user'), 'published', false, null),
    ('Future Post', 'Future content', tests.get_supabase_uid('scheduler'), 'published', false, '2024-01-02 12:00:00+00'::timestamptz)
) as posts(title, content, author_id, status, is_premium, scheduled_for)
where org.slug in ('premium-org', 'schedule-org');

-- Test owner privileges
select tests.authenticate_as('org_owner');
select lives_ok(
  $$
    update organizations
    set name = 'Updated Org'
    where id = (select id from organizations limit 1)
  $$,
  'Owner can update organization'
);

-- Test admin privileges
select tests.authenticate_as('org_admin');
select results_eq(
    $$select count(*) from org_members$$,
    ARRAY[6::bigint],
    'Admin can view all members'
);

-- Test editor restrictions
select tests.authenticate_as('org_editor');
select throws_ok(
  $$
    insert into org_members (org_id, user_id, role)
    values (
      (select id from organizations limit 1),
      (select tests.get_supabase_uid('org_editor')),
      'viewer'
    )
  $$,
  '42501',
  'new row violates row-level security policy for table "org_members"',
  'Editor cannot manage members'
);

-- Premium Content Access Tests
select tests.authenticate_as('premium_user');
select results_eq(
    $$select count(*) from posts where org_id = (select id from organizations where slug = 'premium-org')$$,
    ARRAY[3::bigint],
    'Premium user can see all posts'
);

select tests.clear_authentication();
select results_eq(
    $$select count(*) from posts where org_id = (select id from organizations where slug = 'premium-org')$$,
    ARRAY[2::bigint],
    'Anonymous users can only see free posts'
);

-- Time-Based Publishing Tests
select tests.authenticate_as('scheduler');
select tests.freeze_time('2024-01-01 12:00:00+00'::timestamptz);

select results_eq(
    $$select count(*) from posts where scheduled_for > now() and org_id = (select id from organizations where slug = 'schedule-org')$$,
    ARRAY[1::bigint],
    'Can see scheduled posts'
);

select tests.freeze_time('2024-01-02 13:00:00+00'::timestamptz);

select results_eq(
    $$select count(*) from posts where scheduled_for < now() and org_id = (select id from organizations where slug = 'schedule-org')$$,
    ARRAY[1::bigint],
    'Can see posts after schedule time'
);

select tests.unfreeze_time();

-- Plan Limit Tests
select tests.authenticate_as('free_author');

select lives_ok(
  $$
    insert into posts (title, content, org_id, author_id, status)
    select 'Post 1', 'Content 1', id, auth.uid(), 'draft'
    from organizations where slug = 'free-org' limit 1
  $$,
  'First post creates successfully'
);

select lives_ok(
  $$
    insert into posts (title, content, org_id, author_id, status)
    select 'Post 2', 'Content 2', id, auth.uid(), 'draft'
    from organizations where slug = 'free-org' limit 1
  $$,
  'Second post creates successfully'
);

select throws_ok(
  $$
    insert into posts (title, content, org_id, author_id, status)
    select 'Post 3', 'Content 3', id, auth.uid(), 'draft'
    from organizations where slug = 'free-org' limit 1
  $$,
  '42501',
  'new row violates row-level security policy for table "posts"',
  'Cannot exceed free plan post limit'
);

select * from finish();
rollback;