Request & Response

DahoRequest

The incoming HTTP request handed to route handlers and middleware.

Properties

Property	Type	Description
method	String	HTTP method (GET, POST, etc.)
path	String	Request path (e.g., /users/42)
query	Map<String, String>	Query parameters
params	Map<String, String>	Path parameters (:id → '42')
ip	String	Client IP address
headers	Map<String, String>	Request headers (lowercase keys)
body	dynamic	Parsed request body (lazy)
files	Map<String, UploadedFile>	Uploaded files (lazy)
cookies	Map<String, String>	Parsed cookies (lazy)

Methods

Method	Returns	Description
header(name)	String?	Case-insensitive header lookup

Body Parsing

The body is parsed lazily — only decoded when req.body or req.files is first accessed:

• JSON (application/json) → Map or List
• Form-encoded (application/x-www-form-urlencoded) → Map<String, String>
• Multipart (multipart/form-data) → Map<String, String> for fields, req.files for files
• Plain text → String

app.post('/users', (req, res) {
  final data = req.body; // Parsed based on Content-Type
  return res.ok(data);
});

Reading Headers

// Case-insensitive lookup
final userAgent = req.header('user-agent');
final contentType = req.header('content-type');

// All headers
final allHeaders = req.headers;

DahoResponse

The response builder handed to route handlers. Every mutating method returns this for fluent chaining.

Sending Data

Method	Description
send(text)	Send plain text
json(data)	Serialize as JSON
bytes(raw)	Send raw bytes

res.send('Hello');                           // text/plain
res.json({'name': 'Ada'});                   // application/json
res.bytes([0x89, 0x50, 0x4E, 0x47]);        // application/octet-stream

Status Helpers

Method	Status	Description
ok(data)	200	Success
badRequest(data)	400	Client error
unauthorized(data)	401	Authentication required
forbidden(data)	403	Access denied
notFound(data)	404	Resource not found
internalServerError(data)	500	Server error

Each auto-detects the body type: String → text, Map/List → JSON, List<int> → bytes, null → empty.

res.ok({'users': [...]});              // 200 + JSON
res.badRequest({'error': 'Invalid'});  // 400 + JSON
res.notFound('Page not found');        // 404 + text

Redirects

Method	Status	Description
movedPermanently(location)	301	Permanent redirect
found(location)	302	Temporary redirect
seeOther(location)	303	Redirect after POST
notModified()	304	Not modified

res.movedPermanently('/new-page');
res.found('/login');

Setting Headers

res.header('X-Custom', 'value');
res.status(201);

Fluent Chaining

All methods return this, so you can chain them:

res
    .status(201)
    .header('X-Request-Id', 'abc123')
    .json({'created': true});

Cookies

Setting Cookies

res.cookie(
  'session',
  'abc123',
  maxAge: Duration(hours: 1),
  httpOnly: true,
  secure: true,
  sameSite: 'Lax',
  path: '/',
  domain: '.example.com',
);

Reading Cookies

final sessionId = req.cookies['session'];

Clearing Cookies

res.clearCookie('session');
res.clearCookie('theme', path: '/settings');

UploadedFile

Files from multipart/form-data uploads:

Property	Type	Description
filename	String	Original filename
contentType	String	MIME type (e.g., image/png)
bytes	List<int>	Raw file contents

Method	Description
save(path)	Write to disk (synchronous)
saveAsync(path)	Write to disk (asynchronous)

app.post('/upload', (req, res) {
  final avatar = req.files['avatar'];
  if (avatar == null) return res.badRequest({'error': 'No file'});

  avatar.save('./uploads/${avatar.filename}');

  return res.ok({
    'filename': avatar.filename,
    'type': avatar.contentType,
    'size': avatar.bytes.length,
  });
});