zig- replace Remote.byId with generic byKey

src/db/Remote.zig

@@ -22,11 +22,7 @@ pub const Remote = struct {
         pub const BaseType = string;
     };
 
-    pub fn byID(alloc: *std.mem.Allocator, id: u64) !?Remote {
-        return try db.first(alloc, Remote, "select * from remotes where id = ?", .{
-            .id = id,
-        });
-    }
+    pub const byKey = _internal.ByKeyGen(Remote, "remotes").byKey;
 
     pub fn findUserByName(self: Remote, alloc: *std.mem.Allocator, name: string) !?User {
         return try db.first(alloc, User, "select * from users where provider = ? and name = ?", .{

src/db/_internal.zig

@@ -1,5 +1,43 @@
 const std = @import("std");
+const string = []const u8;
 const zorm = @import("zorm");
 
 pub const Engine = zorm.engine(.sqlite3);
 pub var db: Engine = undefined;
+
+pub fn ByKeyGen(comptime T: type, comptime table_name: string) type {
+    return struct {
+        pub fn byKey(alloc: *std.mem.Allocator, comptime key: std.meta.FieldEnum(T), value: FieldType(T, @tagName(key))) !?T {
+            return try db.first(
+                alloc,
+                T,
+                "select * from " ++ table_name ++ " where " ++ @tagName(key) ++ " = ?",
+                foo(@tagName(key), value),
+            );
+        }
+    };
+}
+
+fn FieldType(comptime T: type, comptime name: string) type {
+    inline for (std.meta.fields(T)) |item| {
+        if (std.mem.eql(u8, item.name, name)) {
+            return item.field_type;
+        }
+    }
+    @compileError(@typeName(T) ++ " does not have a field named " ++ name);
+}
+
+pub fn foo(comptime name: string, value: anytype) Struct(name, @TypeOf(value)) {
+    const T = @TypeOf(value);
+    var x: Struct(name, T) = undefined;
+    @field(x, name) = value;
+    return x;
+}
+
+pub fn Struct(comptime name: string, comptime T: type) type {
+    return @Type(.{ .Struct = .{ .layout = .Auto, .fields = &.{structField(name, T)}, .decls = &.{}, .is_tuple = false } });
+}
+
+pub fn structField(comptime name: string, comptime T: type) std.builtin.TypeInfo.StructField {
+    return .{ .name = name, .field_type = T, .default_value = null, .is_comptime = false, .alignment = @alignOf(T) };
+}

src/handler/package.zig

@@ -8,7 +8,7 @@ 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 r = try db.Remote.byID(alloc, args.remote);
+    const r = try db.Remote.byKey(alloc, .id, args.remote);
     const o = try r.?.findUserByName(alloc, args.user);
     const p = try o.?.findPackageByName(alloc, args.package);
     const v = try p.?.versions(alloc);

src/handler/user.zig

@@ -8,7 +8,7 @@ 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 r = try db.Remote.byID(alloc, args.remote);
+    const r = try db.Remote.byKey(alloc, .id, args.remote);
     const o = try r.?.findUserByName(alloc, args.user);
     const p = try o.?.packages(alloc);