Initial skeleton of support for HTTP

4 files changed, 139 insertions, 0 deletions

diff --git a/src/main/model/http/Header.java b/src/main/model/http/Header.java
new file mode 100644
index 0000000..74d318c
--- /dev/null
+++ b/src/main/model/http/Header.java
@@ -0,0 +1,3 @@
+package model.http;
+
+public record Header(String key, String value) {}
diff --git a/src/main/model/http/Http.java b/src/main/model/http/Http.java
new file mode 100644
index 0000000..9558c79
--- /dev/null
+++ b/src/main/model/http/Http.java
@@ -0,0 +1,45 @@
+package model.http;
+
+import model.util.Uri;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.PrintWriter;
+import java.net.Socket;
+
+// no static classes?? o_o
+// add support for http 0.9 and also http 1.1 as 0.9
+public class Http {
+    private static final String CRLF = "\r\n";
+
+    public static HttpResponse fetch(HttpRequest request, int port) throws IOException, HttpResponse.InvalidResponseException {
+        try (Socket socket = new Socket(request.host(), port);
+             PrintWriter out = new PrintWriter(socket.getOutputStream(), true);
+             BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));) {
+            out.println(request.raw());
+            String bufferOne = "";
+            String bufferTwo = "";
+            String response = "";
+            while (!bufferOne.equals(CRLF) && !bufferTwo.equals(CRLF)) {
+                bufferTwo = bufferOne;
+                bufferOne = in.readLine() + CRLF;
+                response += bufferOne;
+            }
+            return HttpResponse.parse(response);
+        } catch (HttpRequest.MalformedRequestException e) {
+            System.out.println("Failed to make request: " + e.getMessage());
+            return new HttpResponse(600, "Malformed Request");
+        }
+    }
+
+    public static HttpResponse get(Uri location) {
+        // todo
+        return null;
+    }
+
+    public static HttpResponse post(Uri location) {
+        // todo
+        return null;
+    }
+}
diff --git a/src/main/model/http/HttpRequest.java b/src/main/model/http/HttpRequest.java
new file mode 100644
index 0000000..7c27d24
--- /dev/null
+++ b/src/main/model/http/HttpRequest.java
@@ -0,0 +1,57 @@
+package model.http;
+
+import model.util.Uri;
+import java.util.*;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+public record HttpRequest(String method, String target, String version, ArrayList<Header> headers, String body) {
+
+    private static final String CRLF = "\r\n";
+    private static final String DefaultVersion = "HTTP 0.9";
+    private static final Header[] DefaultHeaders = {new Header("User-Agent", "apus")};
+
+    public HttpRequest(String method, String target, String version, ArrayList<Header> headers) {
+        this(method, target, version, headers, "");
+    }
+
+    // note: we disregard the port, that is taken care of by the connecting socket
+    public HttpRequest(String method, Uri uri, String version, String body) {
+        // ah, java
+        this(method, uri.path(), DefaultVersion, new ArrayList<>(Stream.concat(Stream.of(new Header("", "")), Stream.of(DefaultHeaders)).collect(Collectors.toList())));
+    }
+
+    public HttpRequest(String method, Uri uri, String version) {
+        this(method, uri, version, "");
+    }
+
+    public HttpRequest(String method, Uri uri) {
+        this(method, uri, DefaultVersion);
+    }
+
+    // yeah, i probably should just use a hashmap
+    public String host() throws MalformedRequestException {
+        for (Header header : this.headers()) {
+            if (header.key().equals("Host")) {
+                return header.value();
+            }
+        }
+        throw new MalformedRequestException();
+    }
+
+    public static class MalformedRequestException extends Exception {}
+
+    public String raw() {
+        String buffer = "";
+        buffer += this.method() + " " + this.target() + " " + this.version() + CRLF;
+        // hmm maybe i shouldn't use a hashmap
+        for (Header header : this.headers()) {
+            buffer += header.key() + " " + header.value() + CRLF;
+        }
+        if (!this.body().equals("")) {
+            buffer += this.body() + CRLF;
+        }
+        buffer += CRLF;
+        return buffer;
+    }
+}
diff --git a/src/main/model/http/HttpResponse.java b/src/main/model/http/HttpResponse.java
new file mode 100644
index 0000000..65f5bc0
--- /dev/null
+++ b/src/main/model/http/HttpResponse.java
@@ -0,0 +1,34 @@
+package model.http;
+
+import java.util.ArrayList;
+
+public record HttpResponse(String version, int status, String reason, String body, ArrayList<Header> headers) {
+    // for constructing local error responses
+    public HttpResponse(int status, String reason) {
+        this("HTTP 1.1", status, reason, "", new ArrayList<Header>());
+    }
+
+    // probably inefficient but eh
+    public static HttpResponse parse(String response) throws InvalidResponseException {
+        try {
+            var split = response.split("\\r\\n\\r\\n");
+            var lines = split[0].split("\\r\\n");
+            var body = split[1];
+            var start = lines[0].split(" ", 3);
+            var version = start[0];
+            var status = Integer.parseInt(start[1]);
+            var reason = start[2];
+
+            var headers = new ArrayList<Header>();
+            for (int i = 1; i < lines.length; i++) {
+                split = lines[i].split(": ", 2);
+                headers.add(new Header(split[0], split[1]));
+            }
+            return new HttpResponse(version, status, reason, body, headers);
+        } catch (IndexOutOfBoundsException | NumberFormatException e) {
+            throw new InvalidResponseException();
+        }
+    }
+
+    public static class InvalidResponseException extends Exception {}
+}