Web Environment

In a web server context, DWScript provides the WebRequest and WebResponse objects to handle HTTP interaction, and HttpQuery for making outbound requests.

WebRequest

Information about the incoming client request.

Member	Description
`Method`	HTTP verb (GET, POST, etc).
`URL` / `FullURL`	The requested URL.
`RemoteIP`	Client's IP address.
`UserAgent`	Client's browser agent string.
`QueryField[name]`	Accesses GET parameters.
`ContentField[name]`	Accesses POST parameters (Form data).
`Cookie[name]`	Accesses cookies sent by client.
`Header[name]`	Accesses arbitrary HTTP headers.
`ContentType`	MIME type of the request content.
`ContentData`	Raw POST data.

WebResponse

Control the response sent back to the client.

Member	Description
`StatusCode`	HTTP status code (e.g. 200, 404, 301).
`ContentType`	MIME type of response (e.g. 'application/json').
`ContentEncoding`	Encoding of the content (e.g. 'gzip').
`ContentData`	Sets the raw response body.
`ContentText[type]`	Sets content type and text body.
`Header[name]`	Sets a response header.
`Compression`	Enables or disables automatic compression.
`SetCookie(name, val [, expires])`	Sends a cookie to the client.
`SetCookie(name, val, expires, path, ...)`	Sends a cookie with advanced options (domain, flags, sameSite).
`SetStatusRedirect(code, url)`	Issues an HTTP redirect.
`SetStatusPlainText(code, text)`	Sets status code and text content.
`SetStatusJSON(code, json)`	Sets status code and JSON content.
`SetContentJSON(j)`	Sends a JSON object as the response.
`SetContentFile(fileName [, type])`	Sends a file as the response.
`SetETag(etag)`	Sets the ETag header for caching.
`SetCacheControl(control)`	Sets the Cache-Control header.
`SetLastModified(date)`	Sets the Last-Modified header.
`RequestAuthentication(authType)`	Triggers an authentication challenge (e.g. `WebAuthentication.Basic`).

Cookie Security Flags

The advanced SetCookie overload uses a numeric bitmask for flags and an enum for SameSite.

Value	Flag	When to Use
`1`	`Secure`	Always when site uses HTTPS
`2`	`HttpOnly`	Always for session cookies (prevents XSS)

SameSite	Value	Description
`Strict`	`1`	Maximum security, no cross-site requests
`Lax`	`2`	Balanced, allows top-level navigations

Example:

// HttpOnly (2) + Secure (1) = 3
WebResponse.SetCookie('auth', token, expires, '/', '', 3, WebCookieSameSite.Strict);

ServerSentEvents

Support for Server-Sent Events (SSE) to push updates to the client.

Method	Description
`WebServerSentEvents.PostRaw(source, data)`	Posts a raw message to the event stream `source`.
`WebServerSentEvents.Close(source)`	Closes the event stream `source`.
`WebServerSentEvents.Connections(source)`	Returns an array of active connection IDs for `source`.
`WebServerSentEvents.SourceNames`	Returns an array of active event source names.

WebServerSentEvent

Helper class to construct formatted SSE messages.

Member	Description
`ID`, `Name`	Event ID and Event Name.
`Data`	Array of data strings (lines).
`Retry`	Retry interval in milliseconds.
`Post(source)`	Sends the constructed event to `source`.

HttpQuery (Outbound)

Used to make HTTP requests from the server to other web services.

Method	Description
`GetText(url, var data)`	Performs a GET request. Returns status code.
`PostData(url, data, type, var reply)`	Performs a POST request.
`Request(method, url, data, type)`	Performs an arbitrary request and returns an `HttpRequest`.

WebServer Control

The WebServer object allows controlling global server settings, such as URL rewriting.

Member	Description
`SetURLRewriteRulesJSON(json)`	Configures URL rewriting rules using a JSON string.
`GetURLRewriteRules()`	Returns the current rewrite rules as a JSON string.

URL Rewriting

You can define rules to transparently rewrite incoming URLs. This is typically done in the server startup script (.startup.pas).

Rule Format (JSON):

The configuration is an array of rule objects:

pattern: The URL pattern to match. Supports * as a wildcard (matches until the next separator in the pattern).
rewrite: The target URL. Supports $1, $2, ... placeholders corresponding to the * wildcards.

Example:

WebServer.SetURLRewriteRulesJSON(#'[
   { "pattern": "/doc/*", "rewrite": "/doc.dws?id=$1" },
   { "pattern": "/example/*", "rewrite": "/examples/view.dws?example=$1" },
   { "pattern": "/ref/*", "rewrite": "/ref/index.dws?id=$1" }
]');

Example: Fetching External JSON

var data : String;
var status := HttpQuery.GetText('https://api.example.com/status', data);

if status = 200 then
  PrintLn('Response: ' + data);

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