Add support for slices in serialization module

This commit is contained in:
jaina heartles 2022-12-07 01:57:44 -08:00
parent d4cd0e6618
commit cece277eec
3 changed files with 196 additions and 60 deletions

View file

@ -185,16 +185,10 @@ fn Deserializer(comptime Result: type) type {
pub fn parseFormData(comptime T: type, allow_unknown_fields: bool, boundary: []const u8, reader: anytype, alloc: std.mem.Allocator) !T { pub fn parseFormData(comptime T: type, allow_unknown_fields: bool, boundary: []const u8, reader: anytype, alloc: std.mem.Allocator) !T {
var form = openForm(try openMultipart(boundary, reader)); var form = openForm(try openMultipart(boundary, reader));
var ds = Deserializer(T){}; var ds = Deserializer(T).init(alloc);
defer { defer ds.deinit();
var iter = ds.iterator();
while (iter.next()) |pair| {
util.deepFree(alloc, pair.value);
}
}
while (true) { while (true) {
var part = (try form.next(alloc)) orelse break; var part = (try form.next(ds.arena.allocator())) orelse break;
errdefer util.deepFree(alloc, part);
ds.setSerializedField(part.name, part) catch |err| switch (err) { ds.setSerializedField(part.name, part) catch |err| switch (err) {
error.UnknownField => if (allow_unknown_fields) { error.UnknownField => if (allow_unknown_fields) {

View file

@ -101,7 +101,8 @@ pub const Iter = struct {
pub fn parse(alloc: std.mem.Allocator, allow_unknown_fields: bool, comptime T: type, query: []const u8) !T { pub fn parse(alloc: std.mem.Allocator, allow_unknown_fields: bool, comptime T: type, query: []const u8) !T {
var iter = Iter.from(query); var iter = Iter.from(query);
var deserializer = Deserializer(T){}; var deserializer = Deserializer(T).init(alloc);
defer deserializer.deinit();
while (iter.next()) |pair| { while (iter.next()) |pair| {
try deserializer.setSerializedField(pair.key, pair.value); try deserializer.setSerializedField(pair.key, pair.value);

View file

@ -38,14 +38,15 @@ pub fn deserializeString(allocator: std.mem.Allocator, comptime T: type, value:
@compileError("Invalid type " ++ @typeName(T)); @compileError("Invalid type " ++ @typeName(T));
} }
pub fn getRecursiveFieldList(comptime T: type, comptime prefix: FieldRef, comptime options: SerializationOptions) []const FieldRef { fn getStaticFieldList(comptime T: type, comptime prefix: FieldRef, comptime options: SerializationOptions) []const FieldRef {
comptime { comptime {
if (std.meta.trait.is(.Union)(T) and prefix.len == 0 and options.embed_unions) { if (std.meta.trait.is(.Union)(T) and prefix.len == 0 and options.embed_unions) {
@compileError("Cannot embed a union into nothing"); @compileError("Cannot embed a union into nothing");
} }
if (options.isScalar(T)) return &.{prefix}; if (options.isScalar(T)) return &.{prefix};
if (std.meta.trait.is(.Optional)(T)) return getRecursiveFieldList(std.meta.Child(T), prefix, options); if (std.meta.trait.is(.Optional)(T)) return getStaticFieldList(std.meta.Child(T), prefix, options);
if (std.meta.trait.isSlice(T) and !std.meta.trait.isZigString(T)) return &.{};
const eff_prefix: FieldRef = if (std.meta.trait.is(.Union)(T) and options.embed_unions) const eff_prefix: FieldRef = if (std.meta.trait.is(.Union)(T) and options.embed_unions)
prefix[0 .. prefix.len - 1] prefix[0 .. prefix.len - 1]
@ -57,13 +58,47 @@ pub fn getRecursiveFieldList(comptime T: type, comptime prefix: FieldRef, compti
for (std.meta.fields(T)) |f| { for (std.meta.fields(T)) |f| {
const new_prefix = eff_prefix ++ &[_][]const u8{f.name}; const new_prefix = eff_prefix ++ &[_][]const u8{f.name};
const F = f.field_type; const F = f.field_type;
fields = fields ++ getRecursiveFieldList(F, new_prefix, options); fields = fields ++ getStaticFieldList(F, new_prefix, options);
} }
return fields; return fields;
} }
} }
fn getDynamicFieldList(comptime T: type, comptime prefix: FieldRef, comptime options: SerializationOptions) []const DynamicField {
comptime {
if (std.meta.trait.is(.Union)(T) and prefix.len == 0 and options.embed_unions) {
@compileError("Cannot embed a union into nothing");
}
if (options.isScalar(T)) return &.{};
if (std.meta.trait.is(.Optional)(T)) return getDynamicFieldList(std.meta.Child(T), prefix, options);
if (std.meta.trait.isSlice(T) and !std.meta.trait.isZigString(T)) return &.{
.{ .ref = prefix, .child_type = std.meta.Child(T) },
};
const eff_prefix: FieldRef = if (std.meta.trait.is(.Union)(T) and options.embed_unions)
prefix[0 .. prefix.len - 1]
else
prefix;
var fields: []const DynamicField = &.{};
for (std.meta.fields(T)) |f| {
const new_prefix = eff_prefix ++ &[_][]const u8{f.name};
const F = f.field_type;
fields = fields ++ getDynamicFieldList(F, new_prefix, options);
}
return fields;
}
}
const DynamicField = struct {
ref: FieldRef,
child_type: type,
};
pub const SerializationOptions = struct { pub const SerializationOptions = struct {
embed_unions: bool, embed_unions: bool,
isScalar: fn (type) bool, isScalar: fn (type) bool,
@ -74,10 +109,10 @@ pub const default_options = SerializationOptions{
.isScalar = defaultIsScalar, .isScalar = defaultIsScalar,
}; };
fn Intermediary(comptime Result: type, comptime From: type, comptime options: SerializationOptions) type { fn StaticIntermediary(comptime Result: type, comptime From: type, comptime options: SerializationOptions) type {
const field_refs = getRecursiveFieldList(Result, &.{}, options); const field_refs = getStaticFieldList(Result, &.{}, options);
var fields: [field_refs.len]std.builtin.Type.StructField = undefined; var fields: [field_refs.len + 1]std.builtin.Type.StructField = undefined;
for (field_refs) |ref, i| { for (field_refs) |ref, i| {
fields[i] = .{ fields[i] = .{
.name = util.comptimeJoin(".", ref), .name = util.comptimeJoin(".", ref),
@ -88,6 +123,13 @@ fn Intermediary(comptime Result: type, comptime From: type, comptime options: Se
}; };
} }
fields[fields.len - 1] = .{
.name = "__dummy",
.default_value = &1,
.field_type = usize,
.is_comptime = false,
.alignment = @alignOf(usize),
};
return @Type(.{ .Struct = .{ return @Type(.{ .Struct = .{
.layout = .Auto, .layout = .Auto,
.fields = &fields, .fields = &fields,
@ -96,6 +138,109 @@ fn Intermediary(comptime Result: type, comptime From: type, comptime options: Se
} }); } });
} }
fn DynamicIntermediary(comptime Result: type, comptime From: type, comptime options: SerializationOptions) type {
const field_refs = getDynamicFieldList(Result, &.{}, options);
var fields: [field_refs.len + 1]std.builtin.Type.StructField = undefined;
for (field_refs) |f, i| {
const T = std.ArrayListUnmanaged(Intermediary(f.child_type, From, options));
fields[i] = .{
.name = util.comptimeJoin(".", f.ref),
.default_value = &T{},
.field_type = T,
.is_comptime = false,
.alignment = @alignOf(T),
};
}
fields[fields.len - 1] = .{
.name = "__dummy",
.default_value = &1,
.field_type = usize,
.is_comptime = false,
.alignment = @alignOf(usize),
};
return @Type(.{ .Struct = .{
.layout = .Auto,
.fields = &fields,
.decls = &.{},
.is_tuple = false,
} });
}
const SerializationInfo = struct {
max_slice_len: usize = 16,
};
fn getSerializationInfo(
comptime info: anytype,
comptime field_name: []const u8,
comptime info_key: std.meta.FieldEnum(SerializationInfo),
) std.meta.fieldInfo(SerializationInfo, info_key).field_type {
if (@hasDecl(info, "serialization_info") and
@hasDecl(info.serialization_info, field_name) and
@hasDecl(@field(info.serialization_info, field_name), @tagName(info_key)))
{
return @field(@field(info.serialization_info, field_name), @tagName(info_key));
} else return switch (info_key) {
.max_slice_len => 16,
};
}
fn Intermediary(comptime Result: type, comptime From: type, comptime options: SerializationOptions) type {
return struct {
const StaticData = StaticIntermediary(Result, From, options);
const DynamicData = DynamicIntermediary(Result, From, options);
static: StaticData = .{},
dynamic: DynamicData = .{},
fn setSerializedField(self: *@This(), allocator: std.mem.Allocator, key: []const u8, value: From) !void {
var split = std.mem.split(u8, key, "[");
const first = split.first();
const rest = split.rest();
if (rest.len == 0) {
const field = std.meta.stringToEnum(std.meta.FieldEnum(StaticData), key) orelse return error.UnknownField;
inline for (comptime std.meta.fieldNames(StaticData)) |field_name| {
@setEvalBranchQuota(10000);
const f = comptime std.meta.stringToEnum(std.meta.FieldEnum(StaticData), field_name).?;
if (f != .__dummy and field == f) {
@field(self.static, field_name) = value;
return;
}
}
unreachable;
} else {
split = std.mem.split(u8, rest, "]");
const idx_str = split.first();
const idx = try std.fmt.parseInt(usize, idx_str, 10);
var next = split.rest();
if (next.len == 0 or next[0] != '.') return error.UnknownField;
next = next[1..];
std.log.debug("{s} {s} {s}", .{ first, idx_str, next });
const field = std.meta.stringToEnum(std.meta.FieldEnum(DynamicData), first) orelse return error.UnknownField;
inline for (comptime std.meta.fieldNames(DynamicData)) |field_name| {
@setEvalBranchQuota(10000);
const f = comptime std.meta.stringToEnum(std.meta.FieldEnum(DynamicData), field_name).?;
if (f != .__dummy and field == f) {
const limits = getSerializationInfo(Result, field_name, .max_slice_len);
if (idx >= limits) return error.SliceTooLong;
const list = &@field(self.dynamic, field_name);
while (idx >= list.items.len) {
try list.append(allocator, .{});
}
try list.items[idx].setSerializedField(allocator, next, value);
return;
}
}
}
}
};
}
pub fn Deserializer(comptime Result: type) type { pub fn Deserializer(comptime Result: type) type {
return DeserializerContext(Result, []const u8, struct { return DeserializerContext(Result, []const u8, struct {
const options = default_options; const options = default_options;
@ -109,50 +254,21 @@ pub fn DeserializerContext(comptime Result: type, comptime From: type, comptime
return struct { return struct {
const Data = Intermediary(Result, From, Context.options); const Data = Intermediary(Result, From, Context.options);
arena: std.heap.ArenaAllocator,
data: Data = .{}, data: Data = .{},
context: Context = .{}, context: Context = .{},
pub fn init(alloc: std.mem.Allocator) @This() {
return .{ .arena = std.heap.ArenaAllocator.init(alloc) };
}
pub fn deinit(self: *@This()) void {
self.arena.deinit();
}
pub fn setSerializedField(self: *@This(), key: []const u8, value: From) !void { pub fn setSerializedField(self: *@This(), key: []const u8, value: From) !void {
const field = std.meta.stringToEnum(std.meta.FieldEnum(Data), key) orelse return error.UnknownField; try self.data.setSerializedField(self.arena.allocator(), key, value);
inline for (comptime std.meta.fieldNames(Data)) |field_name| {
@setEvalBranchQuota(10000);
const f = comptime std.meta.stringToEnum(std.meta.FieldEnum(Data), field_name);
if (field == f) {
@field(self.data, field_name) = value;
return;
}
}
unreachable;
}
pub const Iter = struct {
data: *const Data,
field_index: usize,
const Item = struct {
key: []const u8,
value: From,
};
pub fn next(self: *Iter) ?Item {
while (self.field_index < std.meta.fields(Data).len) {
const idx = self.field_index;
self.field_index += 1;
inline for (comptime std.meta.fieldNames(Data)) |field, i| {
if (i == idx) {
const maybe_value = @field(self.data.*, field);
if (maybe_value) |value| return Item{ .key = field, .value = value };
}
}
}
return null;
}
};
pub fn iterator(self: *const @This()) Iter {
return .{ .data = &self.data, .field_index = 0 };
} }
pub fn finishFree(_: *@This(), allocator: std.mem.Allocator, val: anytype) void { pub fn finishFree(_: *@This(), allocator: std.mem.Allocator, val: anytype) void {
@ -160,7 +276,7 @@ pub fn DeserializerContext(comptime Result: type, comptime From: type, comptime
} }
pub fn finish(self: *@This(), allocator: std.mem.Allocator) !Result { pub fn finish(self: *@This(), allocator: std.mem.Allocator) !Result {
return (try self.deserialize(allocator, Result, &.{})) orelse error.MissingField; return (try self.deserialize(allocator, Result, self.data, &.{})) orelse error.MissingField;
} }
fn getSerializedField(self: *@This(), comptime field_ref: FieldRef) ?From { fn getSerializedField(self: *@This(), comptime field_ref: FieldRef) ?From {
@ -172,9 +288,16 @@ pub fn DeserializerContext(comptime Result: type, comptime From: type, comptime
util.deepFree(allocator, val); util.deepFree(allocator, val);
} }
fn deserialize(self: *@This(), allocator: std.mem.Allocator, comptime T: type, comptime field_ref: FieldRef) !?T { fn deserialize(
self: *@This(),
allocator: std.mem.Allocator,
comptime T: type,
intermediary: anytype,
comptime field_ref: FieldRef,
) !?T {
if (comptime Context.options.isScalar(T)) { if (comptime Context.options.isScalar(T)) {
return try self.context.deserializeScalar(allocator, T, self.getSerializedField(field_ref) orelse return null); const val = @field(intermediary.static, util.comptimeJoin(".", field_ref));
return try self.context.deserializeScalar(allocator, T, val orelse return null);
} }
switch (@typeInfo(T)) { switch (@typeInfo(T)) {
@ -188,7 +311,7 @@ pub fn DeserializerContext(comptime Result: type, comptime From: type, comptime
inline for (info.fields) |field| { inline for (info.fields) |field| {
const F = field.field_type; const F = field.field_type;
const new_field_ref = union_ref ++ &[_][]const u8{field.name}; const new_field_ref = union_ref ++ &[_][]const u8{field.name};
const maybe_value = try self.deserialize(allocator, F, new_field_ref); const maybe_value = try self.deserialize(allocator, F, intermediary, new_field_ref);
if (maybe_value) |value| { if (maybe_value) |value| {
// TODO: errdefer cleanup // TODO: errdefer cleanup
errdefer self.deserializeFree(allocator, value); errdefer self.deserializeFree(allocator, value);
@ -211,7 +334,7 @@ pub fn DeserializerContext(comptime Result: type, comptime From: type, comptime
inline for (info.fields) |field, i| { inline for (info.fields) |field, i| {
const F = field.field_type; const F = field.field_type;
const new_field_ref = field_ref ++ &[_][]const u8{field.name}; const new_field_ref = field_ref ++ &[_][]const u8{field.name};
const maybe_value = try self.deserialize(allocator, F, new_field_ref); const maybe_value = try self.deserialize(allocator, F, intermediary, new_field_ref);
if (maybe_value) |v| { if (maybe_value) |v| {
@field(result, field.name) = v; @field(result, field.name) = v;
fields_alloced[i] = true; fields_alloced[i] = true;
@ -233,8 +356,26 @@ pub fn DeserializerContext(comptime Result: type, comptime From: type, comptime
return result; return result;
}, },
.Pointer => |info| switch (info.size) {
.Slice => {
const name = comptime util.comptimeJoin(".", field_ref);
const data = @field(self.data.dynamic, name);
const result = try allocator.alloc(info.child, data.items.len);
errdefer allocator.free(result);
var count: usize = 0;
errdefer for (result[0..count]) |res| util.deepFree(allocator, res);
for (data.items) |sub, i| {
result[i] = (try self.deserialize(allocator, info.child, sub, &.{})) orelse return error.SparseSlice;
}
return result;
},
else => @compileError("Unsupported type"),
},
// Specifically non-scalar optionals // Specifically non-scalar optionals
.Optional => |info| return try self.deserialize(allocator, info.child, field_ref), .Optional => |info| return try self.deserialize(allocator, info.child, intermediary, field_ref),
else => @compileError("Unsupported type"), else => @compileError("Unsupported type"),
} }