Merge branch 'release/0.2.0'

README.md

@@ -13,7 +13,7 @@ support for [PKCE](https://datatracker.ietf.org/doc/html/rfc8252#section-8.1) an
 ## Usage
 
 ```java
-// this library will just to the Authorization Flow:
+// this library will just perform the Authorization Flow:
 String tokenResponse = AuthFlow.asClient("oauth-client-id")
         .authorize(URI.create("https://login.example.com/oauth2/authorize"), uri -> System.out.println("Please login on " + uri))
         .getAccessToken(URI.create("https://login.example.com/oauth2/token"));
@@ -33,6 +33,6 @@ The `authorize(...)` method optionally allows you to specify:
 ## Why this library?
 
 * Often you just need to authorize your client and nothing more. Most OAuth2 libraries try to do a lot more
-* Nano-tiny-minuscule attack surface, since this doesn't contain any JOSE/JWT signature code, nor a fully-fleged web server
+* Nano-tiny-minuscule attack surface, since this doesn't contain any JOSE/JWT signature code, nor a fully-fledged web server
 * Focus is strictly on the authorization flow. Use any library for dealing with the tokens, you like.
 * Modular jar, exposing only one single public API. No need to read docs, you can't do anything wrong.

pom.xml

@@ -5,7 +5,7 @@
 	<modelVersion>4.0.0</modelVersion>
 	<groupId>io.github.coffeelibs</groupId>
 	<artifactId>tiny-oauth2-client</artifactId>
-	<version>0.1.1</version>
+	<version>0.2.0</version>
 	<name>Tiny OAuth2 Client</name>
 	<description>Zero Dependency RFC 8252 Authorization Flow</description>
 	<inceptionYear>2022</inceptionYear>

src/main/java/io/github/coffeelibs/tinyoauth2client/AuthFlow.java

@@ -1,8 +1,10 @@
 package io.github.coffeelibs.tinyoauth2client;
 
 import io.github.coffeelibs.tinyoauth2client.http.RedirectTarget;
+import io.github.coffeelibs.tinyoauth2client.http.Response;
 import io.github.coffeelibs.tinyoauth2client.util.RandomUtil;
 import org.jetbrains.annotations.Blocking;
+import org.jetbrains.annotations.Contract;
 import org.jetbrains.annotations.VisibleForTesting;
 
 import java.io.IOException;
@@ -32,6 +34,9 @@ public class AuthFlow {
 	@VisibleForTesting
 	final PKCE pkce;
 
+	private Response successResponse;
+	private Response errorResponse;
+
 	private AuthFlow(String clientId) {
 		this.clientId = clientId;
 		this.pkce = new PKCE();
@@ -47,6 +52,54 @@ public static AuthFlow asClient(String clientId) {
 		return new AuthFlow(clientId);
 	}
 
+	/**
+	 * HTML to display in the Resource Owner's user agent after successful authorization.
+	 *
+	 * @param html content served with {@code Content-Type: text/html; charset=UTF-8}
+	 * @return this
+	 */
+	@Contract("_ -> this")
+	public AuthFlow withSuccessHtml(String html) {
+		this.successResponse = Response.html(Response.Status.OK, html);
+		return this;
+	}
+
+	/**
+	 * Where to redirect the Resource Owner's user agent after successful authorization.
+	 *
+	 * @param target URI of page to show
+	 * @return this
+	 */
+	@Contract("_ -> this")
+	public AuthFlow withSuccessRedirect(URI target) {
+		this.successResponse = Response.redirect(target);
+		return this;
+	}
+
+	/**
+	 * HTML to display in the Resource Owner's user agent after failed authorization.
+	 *
+	 * @param html content served with {@code Content-Type: text/html; charset=UTF-8}
+	 * @return this
+	 */
+	@Contract("_ -> this")
+	public AuthFlow withErrorHtml(String html) {
+		this.errorResponse = Response.html(Response.Status.OK, html);
+		return this;
+	}
+
+	/**
+	 * Where to redirect the Resource Owner's user agent after failed authorization.
+	 *
+	 * @param target URI of page to show
+	 * @return this
+	 */
+	@Contract("_ -> this")
+	public AuthFlow withErrorRedirect(URI target) {
+		this.errorResponse = Response.redirect(target);
+		return this;
+	}
+
 	/**
 	 * Asks the given {@code browser} to browse the authorization URI. This method will block until the browser is
 	 * <a href="https://datatracker.ietf.org/doc/html/rfc8252#section-4.1">redirected back to this application</a>.
@@ -58,6 +111,7 @@ public static AuthFlow asClient(String clientId) {
 	 * @throws IOException In case of I/O errors during communication between browser and this application
 	 * @see #authorize(URI, Consumer, Set, String, int...)
 	 */
+	@Blocking
 	public AuthFlowWithCode authorize(URI authEndpoint, Consumer<URI> browser, String... scopes) throws IOException {
 		return authorize(authEndpoint, browser, Set.of(scopes), "/" + RandomUtil.randomToken(16));
 	}
@@ -77,6 +131,12 @@ public AuthFlowWithCode authorize(URI authEndpoint, Consumer<URI> browser, Strin
 	@Blocking
 	public AuthFlowWithCode authorize(URI authEndpoint, Consumer<URI> browser, Set<String> scopes, String path, int... ports) throws IOException {
 		try (var redirectTarget = RedirectTarget.start(path, ports)) {
+			if (successResponse != null) {
+				redirectTarget.setSuccessResponse(successResponse);
+			}
+			if (errorResponse != null) {
+				redirectTarget.setErrorResponse(errorResponse);
+			}
 			var encodedRedirectUri = URLEncoder.encode(redirectTarget.getRedirectUri().toASCIIString(), StandardCharsets.US_ASCII);
 
 			// https://datatracker.ietf.org/doc/html/rfc6749#section-4.1.1
@@ -107,8 +167,8 @@ public AuthFlowWithCode authorize(URI authEndpoint, Consumer<URI> browser, Set<S
 	 * The successfully authenticated authentication flow, ready to retrieve an access token.
 	 */
 	public class AuthFlowWithCode {
-		private String encodedRedirectUri;
-		private String authorizationCode;
+		private final String encodedRedirectUri;
+		private final String authorizationCode;
 
 		@VisibleForTesting
 		AuthFlowWithCode(String encodedRedirectUri, String authorizationCode) {

src/main/java/io/github/coffeelibs/tinyoauth2client/http/HttpEmptyResponse.java → src/main/java/io/github/coffeelibs/tinyoauth2client/http/EmptyResponse.java

@@ -3,11 +3,11 @@
 import java.io.IOException;
 import java.io.Writer;
 
-class HttpEmptyResponse implements HttpResponse {
+class EmptyResponse implements Response {
 
 	private final Status status;
 
-	public HttpEmptyResponse(HttpResponse.Status status) {
+	public EmptyResponse(Response.Status status) {
 		this.status = status;
 	}
 

src/main/java/io/github/coffeelibs/tinyoauth2client/http/HttpHtmlResponse.java → src/main/java/io/github/coffeelibs/tinyoauth2client/http/HtmlResponse.java

@@ -4,12 +4,12 @@
 import java.io.Writer;
 import java.nio.charset.StandardCharsets;
 
-class HttpHtmlResponse implements HttpResponse {
+class HtmlResponse implements Response {
 
 	private final Status status;
 	private final String body;
 
-	public HttpHtmlResponse(Status status, String body) {
+	public HtmlResponse(Status status, String body) {
 		this.status = status;
 		this.body = body;
 	}

src/main/java/io/github/coffeelibs/tinyoauth2client/http/InvalidRequestException.java

@@ -1,9 +1,9 @@
 package io.github.coffeelibs.tinyoauth2client.http;
 
 public class InvalidRequestException extends Exception {
-	public final HttpResponse suggestedResponse;
+	public final Response suggestedResponse;
 
-	public InvalidRequestException(HttpResponse suggestedResponse) {
+	public InvalidRequestException(Response suggestedResponse) {
 		this.suggestedResponse = suggestedResponse;
 	}
 

src/main/java/io/github/coffeelibs/tinyoauth2client/http/HttpRedirectResponse.java → src/main/java/io/github/coffeelibs/tinyoauth2client/http/RedirectResponse.java

@@ -4,12 +4,12 @@
 import java.io.Writer;
 import java.net.URI;
 
-class HttpRedirectResponse implements HttpResponse {
+class RedirectResponse implements Response {
 
 	private final Status status;
 	private URI target;
 
-	public HttpRedirectResponse(Status status, URI target) {
+	public RedirectResponse(Status status, URI target) {
 		this.status = status;
 		this.target = target;
 	}

src/main/java/io/github/coffeelibs/tinyoauth2client/http/RedirectTarget.java

@@ -16,6 +16,7 @@
 import java.nio.channels.ServerSocketChannel;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Path;
+import java.util.Objects;
 
 /**
  * A TCP connector to deal with the redirect response. We only listen for the expected response,
@@ -36,7 +37,8 @@ public class RedirectTarget implements Closeable {
 	private final String path;
 	private final String csrfToken;
 
-	private HttpResponse successResponse = HttpResponse.html(HttpResponse.Status.OK, "<html><body>Success</body></html>"); // TODO: allow customization with custom html or redirect
+	private Response successResponse = Response.html(Response.Status.OK, "<html><body>Success</body></html>");
+	private Response errorResponse = Response.html(Response.Status.OK, "<html><body>Error</body></html>");
 
 	private RedirectTarget(ServerSocketChannel serverChannel, String path) {
 		this.serverChannel = serverChannel;
@@ -91,6 +93,14 @@ static void tryBind(ServerSocketChannel ch, int... ports) throws IOException {
 		}
 	}
 
+	public void setSuccessResponse(Response successResponse) {
+		this.successResponse = Objects.requireNonNull(successResponse);
+	}
+
+	public void setErrorResponse(Response errorResponse) {
+		this.errorResponse = Objects.requireNonNull(errorResponse);
+	}
+
 	public URI getRedirectUri() {
 		try {
 			// use 127.0.0.1, not "localhost", see https://datatracker.ietf.org/doc/html/rfc8252#section-8.3
@@ -126,23 +136,24 @@ public String receive() throws IOException {
 				throw new IOException("Unparseable Request", e);
 			}
 			if (!Path.of(path).equals(Path.of(requestUri.getPath()))) {
-				HttpResponse.empty(HttpResponse.Status.NOT_FOUND).write(writer);
+				Response.empty(Response.Status.NOT_FOUND).write(writer);
 				throw new IOException("Requested invalid path " + requestUri);
 			}
 
 			var params = URIUtil.parseQueryString(requestUri.getRawQuery());
 			if (!csrfToken.equals(params.get("state"))) {
-				HttpResponse.empty(HttpResponse.Status.BAD_REQUEST).write(writer);
+				Response.empty(Response.Status.BAD_REQUEST).write(writer);
 				throw new IOException("Missing or invalid state token");
 			} else if (params.containsKey("error")) {
-				var html = "<html><body>" + params.get("error") + "</body></html>";
-				HttpResponse.html(HttpResponse.Status.OK, html).write(writer);
+//				var html = "<html><body>" + params.get("error") + "</body></html>";
+//				Response.html(Response.Status.OK, html).write(writer);
+				errorResponse.write(writer); // TODO insert error code?
 				throw new IOException("Authorization failed"); // TODO more specific exception containing the error code
 			} else if (params.containsKey("code")) {
 				successResponse.write(writer);
 				return params.get("code");
 			} else {
-				HttpResponse.empty(HttpResponse.Status.BAD_REQUEST).write(writer);
+				Response.empty(Response.Status.BAD_REQUEST).write(writer);
 				throw new IOException("Missing authorization code");
 			}
 		}
@@ -159,16 +170,16 @@ public String receive() throws IOException {
 	static URI parseRequestLine(String requestLine) throws InvalidRequestException {
 		var words = requestLine.split(" ");
 		if (words.length < 3) {
-			throw new InvalidRequestException(HttpResponse.empty(HttpResponse.Status.BAD_REQUEST));
+			throw new InvalidRequestException(Response.empty(Response.Status.BAD_REQUEST));
 		}
 		var method = words[0];
 		if (!"GET".equals(method)) {
-			throw new InvalidRequestException(HttpResponse.empty(HttpResponse.Status.METHOD_NOT_ALLOWED));
+			throw new InvalidRequestException(Response.empty(Response.Status.METHOD_NOT_ALLOWED));
 		}
 		try {
 			return new URI(words[1]);
 		} catch (URISyntaxException e) {
-			throw new InvalidRequestException(HttpResponse.empty(HttpResponse.Status.BAD_REQUEST));
+			throw new InvalidRequestException(Response.empty(Response.Status.BAD_REQUEST));
 		}
 	}
 

src/main/java/io/github/coffeelibs/tinyoauth2client/http/HttpResponse.java → src/main/java/io/github/coffeelibs/tinyoauth2client/http/Response.java

@@ -4,20 +4,20 @@
 import java.io.Writer;
 import java.net.URI;
 
-interface HttpResponse {
+public interface Response {
 
 	void write(Writer writer) throws IOException;
 
-	static HttpResponse empty(Status status) {
-		return new HttpEmptyResponse(status);
+	static Response empty(Status status) {
+		return new EmptyResponse(status);
 	}
 
-	static HttpResponse html(Status status, String body) {
-		return new HttpHtmlResponse(status, body);
+	static Response html(Status status, String body) {
+		return new HtmlResponse(status, body);
 	}
 
-	static HttpResponse redirect(URI target) {
-		return new HttpRedirectResponse(Status.SEE_OTHER, target);
+	static Response redirect(URI target) {
+		return new RedirectResponse(Status.SEE_OTHER, target);
 	}
 
 	enum Status {