Add CGI handling to my basic server

Fix some missing bits from the comments CGI program, specifically
- respect content_length from the web server
- write the http status response as a header in the result

1 files changed, 22 insertions, 9 deletions

diff --git a/comments/src/main.zig b/comments/src/main.zig
index ac8193e..4044ae7 100644
--- a/comments/src/main.zig
+++ b/comments/src/main.zig
@@ -35,6 +35,8 @@ const Err = error{
     SystemResources,
     Unexpected,
     WouldBlock,
+    Overflow,
+    EndOfStream,
 };
 const Ctx = struct {
     db: pq.Db,
@@ -80,13 +82,19 @@ const Response = struct {
         return std.io.getStdIn().reader();
     }
     fn do(self: @This()) !void {
+        const wtr = std.io.getStdOut().writer();
+        if (self.status.phrase()) |phrase| {
+            try std.fmt.format(wtr, "status: {} {s}\r\n", .{@intFromEnum(self.status), phrase});
+        } else {
+            try std.fmt.format(wtr, "status: {}\r\n", .{@intFromEnum(self.status)});
+        }
         for (self.headers._internal.items) |tup| {
-            try std.io.getStdOut().writeAll(tup.key);
-            try std.io.getStdOut().writeAll(": ");
-            try std.io.getStdOut().writeAll(tup.val);
-            try std.io.getStdOut().writeAll("\r\n");
+            try wtr.writeAll(tup.key);
+            try wtr.writeAll(": ");
+            try wtr.writeAll(tup.val);
+            try wtr.writeAll("\r\n");
         }
-        try std.io.getStdOut().writeAll("\r\n");
+        try wtr.writeAll("\r\n");
     }
     fn writer(_: @This()) std.fs.File.Writer {
         return std.io.getStdOut().writer();
@@ -136,7 +144,7 @@ pub fn main() !void {
     var res = Response{
         .allocator = allocator,
         .request = req,
-        .status = .bad_request,
+        .status = .ok,
         .transfer_encoding = .none,
         .headers = Headers.init(allocator),
     };
@@ -203,9 +211,12 @@ fn get_comment(res: *Response, ctx: Ctx, _: Params) Err!void {
 }
 
 fn post_comment(res: *Response, ctx: Ctx, _: Params) Err!void {
-    var body_aa = std.ArrayList(u8).init(res.allocator);
-    try res.reader().readAllArrayList(&body_aa, 1_000_000);
-    const body = try body_aa.toOwnedSlice();
+    const cl = if (std.os.getenv("CONTENT_LENGTH")) |clh| try std.fmt.parseInt(usize, clh, 10) else {
+        return error.InvalidLength;
+    };
+    const body = try res.allocator.alloc(u8, cl);
+    defer res.allocator.free(body);
+    try res.reader().readNoEof(body);
     var form = try zws.Form.parse(res.allocator, body);
     const Form = struct {
         url: []const u8,
@@ -215,6 +226,7 @@ fn post_comment(res: *Response, ctx: Ctx, _: Params) Err!void {
         capcha_answer: []const u8,
     };
     const form_val = form.form_to_struct(Form) catch {
+        std.log.err("couldn't parse Form", .{});
         try badrequest(res, ctx);
         return;
     };
@@ -231,6 +243,7 @@ fn post_comment(res: *Response, ctx: Ctx, _: Params) Err!void {
         }
         const ans = try stmt.read_column(0, []const u8);
         if (!std.mem.eql(u8, ans, form_val.capcha_answer)) {
+            std.log.err("bad capcha answer {s} expected {s}", .{form_val.capcha_answer, ans});
             try constresponse(res, @embedFile("templates/capchainvalid.html"), std.http.Status.unauthorized);
             return;
         }