name	basil-development
description	Develop and test Basil web applications with HTTP handlers, routing, sessions, authentication, databases, and interactive components (Parts).

Basil Development

When to use this skill

Use when:

building Basil web apps,
configuring basil.yaml,
testing handlers with curl,
working with @basil/http
working with @basil/auth context,
debugging routing and Parts.

Use this skill when you need to:

What is Basil?

Basil is a web framework for Parsley (the language):

Parsley = the language (like JavaScript)
Basil = the web framework (like Express/Rails)

Basil provides HTTP server, routing, sessions, auth, database, interactive components (Parts), and asset bundling.

Quick Start

# Initialize project
./basil --init myapp && cd myapp

# Run dev server (auto-reload, detailed errors, dev tools at /__dev/log)
./basil --dev

# Test
curl http://localhost:8080/

Core Concepts

1. Handlers

Parsley files that handle HTTP requests.

// site/index.pars
<html>
<body>
  <h1>"Welcome!"</h1>
  <p>`Search: {@params.q ?? 'none'}`</p>
</body>
</html>

2. Configuration (basil.yaml)

server:
  port: 8080
site:
  path: ./site         # Filesystem routing: site/about.pars → /about
database:
  path: ./data.db      # Database
session:
  secret: "your-32-char-secret"  # Required for sessions

3. Parts (Interactive Components)

.part files with functions that return HTML. Update without page reload.

// parts/counter.part
export default = fn(props) {
  let count = props.count ?? 0
  <div>
    <p>`Count: {count}`</p>
    <button part-click="increment" part-count={count + 1}>"++"</button>
  </div>
}

export increment = fn(props) {
  default(props)  // Re-render with new count
}

Usage:

<Part src={@~/parts/counter.part} count={0}/>

Important: Parts need routes in basil.yaml:

routes:
  - path: /parts/counter.part
    handler: ./parts/counter.part

Essential Imports

HTTP Context (@basil/http)

let {request, response, method} = import @basil/http
let {redirect} = import @std/api

@params         // URL/form params: {id: "123"}
method          // "GET", "POST", etc.
request.body    // Request body (JSON auto-parsed)
request.path    // "/api/users/123"
response.status = 404
redirect("/dashboard")    // Returns redirect response

Auth Context (@basil/auth)

let {session, user} = import @basil/auth

// Sessions
session.set("cart", ["item1", "item2"])
let cart = session.get("cart", [])
session.flash("success", "Saved!")  // Show-once message

// Current user (null if not logged in)
if (user) {
  user.email
  user.role  // "admin", "user", etc.
}

Magic Variables

@params         // URL/form parameters
@DB             // Server database (configured in basil.yaml)
@now            // Current datetime
@env.HOME       // Environment variables

Database Operations

// Use @DB magic variable for database access
let id = 123
let user = @DB <=?=> `SELECT * FROM users WHERE id = {id}`  // One row
let users = @DB <=??=> "SELECT * FROM users"                    // All rows
let name = "Alice"
let result = @DB <=!=> `INSERT INTO users (name) VALUES ('{name}')`  // Mutation

// See docs/basil/reference.md for complete database API

Common Handler Patterns

Database Query Handler

let users = @DB <=??=> "SELECT * FROM users ORDER BY name"

<html>
<body>
  <ul>
    for (user in users) {
      <li>user.name</li>
    }
  </ul>
</body>
</html>

JSON API Handler

let {method} = import @basil/http

if (method == "GET") {
  let users = @DB <=??=> "SELECT id, name FROM users"
  {users: users}
} else if (method == "POST") {
  let result = @DB <=!=> `INSERT INTO users (name) VALUES ('{@params.name}')`
  let id = @DB.lastInsertId()
  {id: id}
}

Form Handler

let {method, request} = import @basil/http
let {session} = import @basil/auth
let {redirect} = import @std/api

if (method == "POST") {
  let form = request.form
  // Process form...
  session.flash("success", "Saved!")
  redirect("/")
} else {
  <form method="POST">
    <input name="email" required/>
    <button>"Submit"</button>
  </form>
}

Testing with curl

# GET
curl http://localhost:8080/

# With query params
curl "http://localhost:8080/search?q=test"

# POST form
curl -X POST http://localhost:8080/contact -d "name=Alice&email=alice@example.com"

# JSON API
curl http://localhost:8080/api/users -H "Content-Type: application/json" -d '{"name":"Alice"}'

# With cookies
curl -c cookies.txt http://localhost:8080/login -d "user=admin&pass=secret"
curl -b cookies.txt http://localhost:8080/dashboard

Common Pitfalls

Parts need routes - Add to basil.yaml routes:
Parts export functions only - No variables in .part files
Session secret required - Set in basil.yaml for persistent sessions
Database path relative to config - Not to handler file
File writes need whitelist - Use security.allow_write in config

Quick Reference

Commands

./basil --init myapp        # Create project
./basil --dev               # Run dev server
./basil --dev --port 3000   # Custom port

Config Essentials

server:
  port: 8080
site:
  path: ./site            # Filesystem routing
database:
  path: ./data.db         # Database
session:
  secret: "32-char-secret"
auth:
  enabled: true
  protected_paths: ["/admin"]

Import Essentials

let {method, request, response} = import @basil/http
let {session, user} = import @basil/auth
let {redirect, notFound} = import @std/api

Detailed Documentation

For comprehensive guides, see:

references/CONFIGURATION.md - Complete basil.yaml reference
references/PARTS.md - Interactive components guide
references/DATABASE.md - Database operations
references/TESTING.md - Testing strategies
Basil API: docs/basil/reference.md - Full language reference with all operators and builtins
Parsley: docs/parsley/CHEATSHEET.md and docs/parsley/reference.md

Best Practices

Use ./basil --dev for auto-reload and detailed errors
Test with curl before browser testing
Check http://localhost:8080/__dev/log for debugging
Validate Parsley with ./pars before using in handlers
Use {data, error} pattern for error handling
Set session secret for persistent sessions
Whitelist directories for file operations

name	basil-development
description	Develop and test Basil web applications with HTTP handlers, routing, sessions, authentication, databases, and interactive components (Parts).

Basil Development

When to use this skill

Use when:

building Basil web apps,
configuring basil.yaml,
testing handlers with curl,
working with @basil/http
working with @basil/auth context,
debugging routing and Parts.

Use this skill when you need to:

What is Basil?

Basil is a web framework for Parsley (the language):

Parsley = the language (like JavaScript)
Basil = the web framework (like Express/Rails)

Basil provides HTTP server, routing, sessions, auth, database, interactive components (Parts), and asset bundling.

Quick Start

# Initialize project
./basil --init myapp && cd myapp

# Run dev server (auto-reload, detailed errors, dev tools at /__dev/log)
./basil --dev

# Test
curl http://localhost:8080/

Core Concepts

1. Handlers

Parsley files that handle HTTP requests.

// site/index.pars
<html>
<body>
  <h1>"Welcome!"</h1>
  <p>`Search: {@params.q ?? 'none'}`</p>
</body>
</html>

2. Configuration (basil.yaml)

server:
  port: 8080
site:
  path: ./site         # Filesystem routing: site/about.pars → /about
database:
  path: ./data.db      # Database
session:
  secret: "your-32-char-secret"  # Required for sessions

3. Parts (Interactive Components)

.part files with functions that return HTML. Update without page reload.

// parts/counter.part
export default = fn(props) {
  let count = props.count ?? 0
  <div>
    <p>`Count: {count}`</p>
    <button part-click="increment" part-count={count + 1}>"++"</button>
  </div>
}

export increment = fn(props) {
  default(props)  // Re-render with new count
}

Usage:

<Part src={@~/parts/counter.part} count={0}/>

Important: Parts need routes in basil.yaml:

routes:
  - path: /parts/counter.part
    handler: ./parts/counter.part

Essential Imports

HTTP Context (@basil/http)

let {request, response, method} = import @basil/http
let {redirect} = import @std/api

@params         // URL/form params: {id: "123"}
method          // "GET", "POST", etc.
request.body    // Request body (JSON auto-parsed)
request.path    // "/api/users/123"
response.status = 404
redirect("/dashboard")    // Returns redirect response

Auth Context (@basil/auth)

let {session, user} = import @basil/auth

// Sessions
session.set("cart", ["item1", "item2"])
let cart = session.get("cart", [])
session.flash("success", "Saved!")  // Show-once message

// Current user (null if not logged in)
if (user) {
  user.email
  user.role  // "admin", "user", etc.
}

Magic Variables

@params         // URL/form parameters
@DB             // Server database (configured in basil.yaml)
@now            // Current datetime
@env.HOME       // Environment variables

Database Operations

// Use @DB magic variable for database access
let id = 123
let user = @DB <=?=> `SELECT * FROM users WHERE id = {id}`  // One row
let users = @DB <=??=> "SELECT * FROM users"                    // All rows
let name = "Alice"
let result = @DB <=!=> `INSERT INTO users (name) VALUES ('{name}')`  // Mutation

// See docs/basil/reference.md for complete database API

Common Handler Patterns

Database Query Handler

let users = @DB <=??=> "SELECT * FROM users ORDER BY name"

<html>
<body>
  <ul>
    for (user in users) {
      <li>user.name</li>
    }
  </ul>
</body>
</html>

JSON API Handler

let {method} = import @basil/http

if (method == "GET") {
  let users = @DB <=??=> "SELECT id, name FROM users"
  {users: users}
} else if (method == "POST") {
  let result = @DB <=!=> `INSERT INTO users (name) VALUES ('{@params.name}')`
  let id = @DB.lastInsertId()
  {id: id}
}

Form Handler

let {method, request} = import @basil/http
let {session} = import @basil/auth
let {redirect} = import @std/api

if (method == "POST") {
  let form = request.form
  // Process form...
  session.flash("success", "Saved!")
  redirect("/")
} else {
  <form method="POST">
    <input name="email" required/>
    <button>"Submit"</button>
  </form>
}

Testing with curl

# GET
curl http://localhost:8080/

# With query params
curl "http://localhost:8080/search?q=test"

# POST form
curl -X POST http://localhost:8080/contact -d "name=Alice&email=alice@example.com"

# JSON API
curl http://localhost:8080/api/users -H "Content-Type: application/json" -d '{"name":"Alice"}'

# With cookies
curl -c cookies.txt http://localhost:8080/login -d "user=admin&pass=secret"
curl -b cookies.txt http://localhost:8080/dashboard

Common Pitfalls

Parts need routes - Add to basil.yaml routes:
Parts export functions only - No variables in .part files
Session secret required - Set in basil.yaml for persistent sessions
Database path relative to config - Not to handler file
File writes need whitelist - Use security.allow_write in config

Quick Reference

Commands

./basil --init myapp        # Create project
./basil --dev               # Run dev server
./basil --dev --port 3000   # Custom port

Config Essentials

server:
  port: 8080
site:
  path: ./site            # Filesystem routing
database:
  path: ./data.db         # Database
session:
  secret: "32-char-secret"
auth:
  enabled: true
  protected_paths: ["/admin"]

Import Essentials

let {method, request, response} = import @basil/http
let {session, user} = import @basil/auth
let {redirect, notFound} = import @std/api

Detailed Documentation

For comprehensive guides, see:

references/CONFIGURATION.md - Complete basil.yaml reference
references/PARTS.md - Interactive components guide
references/DATABASE.md - Database operations
references/TESTING.md - Testing strategies
Basil API: docs/basil/reference.md - Full language reference with all operators and builtins
Parsley: docs/parsley/CHEATSHEET.md and docs/parsley/reference.md

Best Practices

Use ./basil --dev for auto-reload and detailed errors
Test with curl before browser testing
Check http://localhost:8080/__dev/log for debugging
Validate Parsley with ./pars before using in handlers
Use {data, error} pattern for error handling
Set session secret for persistent sessions
Whitelist directories for file operations

basil-development

Basil Development

When to use this skill

What is Basil?

Quick Start

Core Concepts

1. Handlers

2. Configuration (basil.yaml)

3. Parts (Interactive Components)

Essential Imports

HTTP Context (@basil/http)

Auth Context (@basil/auth)

Magic Variables

Database Operations

Common Handler Patterns

Database Query Handler

JSON API Handler

Form Handler

Testing with curl

Common Pitfalls

Quick Reference

Commands

Config Essentials

Import Essentials

Detailed Documentation

Best Practices

このリポジトリの他の Skills

このリポジトリの他の Skills

Basil Development

When to use this skill

What is Basil?

Quick Start

Core Concepts

1. Handlers

2. Configuration (basil.yaml)

3. Parts (Interactive Components)

Essential Imports

HTTP Context (@basil/http)

Auth Context (@basil/auth)

Magic Variables

Database Operations

Common Handler Patterns

Database Query Handler

JSON API Handler

Form Handler

Testing with curl

Common Pitfalls

Quick Reference

Commands

Config Essentials

Import Essentials

Detailed Documentation

Best Practices