zig/handler- add helpers to gracefully handle invalid paths

src/handler/_internal.zig

@@ -138,12 +138,29 @@ pub fn fileList(alloc: std.mem.Allocator, path: string) ![]const string {
 
 pub fn assert(cond: bool, response: *http.Response, comptime fmt: string, args: anytype) !void {
     if (!cond) {
-        try response.writer().print(fmt, args);
-        return error.HttpNoOp;
+        return fail(response, fmt, args);
     }
 }
 
 pub fn fail(response: *http.Response, comptime fmt: string, args: anytype) (http.Response.Writer.Error || error{HttpNoOp}) {
     try response.writer().print(fmt, args);
     return error.HttpNoOp;
 }
+
+pub fn reqRemote(request: http.Request, response: *http.Response, id: u64) !db.Remote {
+    const alloc = request.arena;
+    const r = try db.Remote.byKey(alloc, .id, id);
+    return r orelse fail(response, "error: remote by id '{d}' not found\n", .{id});
+}
+
+pub fn reqUser(request: http.Request, response: *http.Response, r: db.Remote, name: string) !db.User {
+    const alloc = request.arena;
+    const u = try r.findUserBy(alloc, .name, name);
+    return u orelse fail(response, "error: user by name '{s}' not found\n", .{name});
+}
+
+pub fn reqPackage(request: http.Request, response: *http.Response, u: db.User, name: string) !db.Package {
+    const alloc = request.arena;
+    const p = try u.findPackageBy(alloc, .name, name);
+    return p orelse fail(response, "error: package by name '{s}' not found\n", .{name});
+}

src/handler/package.zig

@@ -9,17 +9,17 @@ const _internal = @import("./_internal.zig");
 pub fn get(_: void, response: *http.Response, request: http.Request, args: struct { remote: u64, user: string, package: string }) !void {
     const alloc = request.arena;
     const u = try _internal.getUserOp(response, request);
-    const r = try db.Remote.byKey(alloc, .id, args.remote);
-    const o = try r.?.findUserBy(alloc, .name, args.user);
-    const p = try o.?.findPackageBy(alloc, .name, args.package);
-    const v = try p.?.versions(alloc);
+    const r = try _internal.reqRemote(request, response, args.remote);
+    const o = try _internal.reqUser(request, response, r, args.user);
+    const p = try _internal.reqPackage(request, response, o, args.package);
+    const v = try p.versions(alloc);
 
     try _internal.writePageResponse(alloc, response, request, "/package.pek", .{
         .aquila_version = @import("root").version,
         .user = u,
-        .repo = r.?,
-        .owner = o.?,
-        .pkg = p.?,
+        .repo = r,
+        .owner = o,
+        .pkg = p,
         .versions = v,
     });
 }

src/handler/user.zig

@@ -9,15 +9,15 @@ const _internal = @import("./_internal.zig");
 pub fn get(_: void, response: *http.Response, request: http.Request, args: struct { remote: u64, user: string }) !void {
     const alloc = request.arena;
     const u = try _internal.getUserOp(response, request);
-    const r = try db.Remote.byKey(alloc, .id, args.remote);
-    const o = try r.?.findUserBy(alloc, .name, args.user);
-    const p = try o.?.packages(alloc);
+    const r = try _internal.reqRemote(request, response, args.remote);
+    const o = try _internal.reqUser(request, response, r, args.user);
+    const p = try o.packages(alloc);
 
     try _internal.writePageResponse(alloc, response, request, "/user.pek", .{
         .aquila_version = @import("root").version,
         .user = u,
-        .repo = r.?,
-        .owner = o.?,
+        .repo = r,
+        .owner = o,
         .pkgs = p,
     });
 }