Flod Logo

Flod — schema validation for Dart & Flutter #

Flod is a strict, fast, type-safe data validation and transformation engine for Dart and Flutter. If you know Zod (TypeScript) or Zod-inspired APIs, Flod will feel immediately familiar — with the extras that matter in production: PII-safe errors, JSON hardening, Dio middleware, Flutter form bridging, and a compiled performance layer.

Examples #

Add Flod and import the core API:

dependencies:
  flod: ^1.1.3

import 'package:flod/flod.dart';

Validate an API payload #

final checkoutSchema = Flod.object({
  'id': Flod.int().positive(),
  'email': Flod.string().trim().toLowerCase().email(),
  'role': Flod.literal('user'),
  'profile': Flod.object({
    'displayName': Flod.string().min(2).max(64).trim(),
    'age': Flod.int().min(13).max(120).optional(),
    'tags': Flod.list(schema: Flod.string().trim()).min(0).max(10).uniqueItems(),
  }),
  'items': Flod.list(
    schema: Flod.object({
      'sku': Flod.string().min(3).max(32),
      'qty': Flod.int().positive().max(999),
      'price': Flod.double().nonNegative(),
    }),
  ).min(1),
});

final result = checkoutSchema.safeParse(jsonMap);

if (result is FlodSuccess<Map<String, dynamic>>) {
  final data = result.data; // validated + transformed
} else if (result is FlodFailure<Map<String, dynamic>>) {
  print(result.toReadable());   // human-readable lines
  print(result.getFieldsMap()); // {"profile.age": "..."}
}

`safeParse` vs `parse` #

final userSchema = Flod.object({
  'name': Flod.string().min(2),
  'age': Flod.int().min(0),
});

// Recommended — no exceptions
final result = userSchema.safeParse({'name': 'A', 'age': -1});
if (result is FlodFailure) {
  print(result.toReadable());
}

// Fail-fast — throws ValidationException
try {
  userSchema.parse({'name': 'A', 'age': -1});
} on ValidationException catch (e) {
  for (final err in e.errors) {
    print('${err.path.toReadable()}: ${err.code}');
  }
}

Stop at the first error when you only need a yes/no answer:

schema.safeParse(data, abortEarly: true);
schema.parse(data, abortEarly: true);
await schema.safeParseAsync(data, abortEarly: true);

final strictFast = schema.stopOnFirstError();
strictFast.safeParse(data);

Strings, numbers, and formats #

Flod.string().email();
Flod.string().url();
Flod.string().uuid();
Flod.string().phoneNumber();
Flod.string().creditCard(); // Luhn
Flod.string().cvv();
Flod.string().min(8).regex(RegExp(r'[A-Z]'), code: 'needs_uppercase');
Flod.string().length(2);    // fixed length

Flod.int().min(0).max(120);
Flod.int().positive();
Flod.int().multipleOf(7);
Flod.double().nonNegative();
Flod.boolean();
Flod.literal('admin');

Coerce form strings and stringly JSON #

The same schema can accept typed JSON and TextFormField strings.

final formSchema = Flod.object({
  'age': Flod.coerce.int().min(18, message: 'Must be 18+'),
  'price': Flod.coerce.double().nonNegative(),
  'active': Flod.coerce.boolean(),
  'note': Flod.coerce.string().max(200),
});

formSchema.safeParse({
  'age': '22',     // → 22
  'price': '9.99', // → 9.99
  'active': 'yes', // → true
  'note': 42,      // → "42"
});

Flod.int() stays strict and still rejects "42". Use Flod.coerce.int() when the input may be a string.

Transform before validation #

final usernameFromEmail = Flod.string().trim().toLowerCase().transform(
  (v) => v.split('@').first,
);

final result = usernameFromEmail.safeParse('  John.Doe@Example.com  ');
// result.data → "john.doe"

Built-ins: .trim(), .toLowerCase(), .toUpperCase(), .transform(fn).

Nested objects, lists, and unions #

Flod.object({'a': Flod.string()}).strict();      // unknown keys → error
Flod.object({'a': Flod.string()}).passthrough(); // extra keys kept

Flod.list(schema: Flod.int()).min(1).max(100).uniqueItems();

final eventSchema = Flod.union([
  Flod.object({'kind': Flod.literal('click'), 'x': Flod.int()}),
  Flod.object({'kind': Flod.literal('view'), 'duration': Flod.int()}),
]).discriminatedBy('kind');

Nested failures keep a full path: company.department.team.lead.analytics.age.

Recursive trees with `Flod.lazy` #

late final Validator<Map<String, dynamic>> category;

category = Flod.object({
  'name': Flod.string().min(1),
  'children': Flod.list(schema: Flod.lazy(() => category)),
});

category.safeParse({
  'name': 'root',
  'children': [
    {'name': 'child', 'children': []},
  ],
});

Defaults, optional, and nullable #

Flod.int().nonNegative().withDefault(0);           // missing / null → 0
Flod.string().nullable();                          // key present, value may be null
Flod.int().optional();                             // key may be absent

Flod.list(schema: Flod.string()).withDefaultFactory(() => <String>[]);

Flod.object({'tags': Flod.list(schema: Flod.string())})
    .withDefaultFactory(() => {'tags': <String>[]});

Lists and maps passed to withDefault are shallow-cloned on every use, so mutating one result does not leak into the next parse.

Cross-field rules #

final signupSchema = Flod.object({
  'password': Flod.string().min(8),
  'confirmPassword': Flod.string(),
}).refine(
  (data) => data['password'] == data['confirmPassword'],
  code: 'passwords_match',
  path: ['confirmPassword'],
  message: 'Passwords do not match',
);

Flod.string().email().refine(
  (email) => !email.endsWith('@tempmail.com'),
  message: 'Disposable emails are not allowed',
);

schema.superRefine((value, ctx) {
  if (value['age'] < 18 && value['country'] == 'US') {
    ctx.addIssue(code: 'too_young', path: ['age'], message: 'Too young for US');
  }
});

Async variants: .refineAsync() / .superRefineAsync() with safeParseAsync().

Inline error copy #

Flod.string().min(8, message: 'Password too short');
Flod.int().min(18, message: 'Must be 18+');
Flod.list(schema: Flod.int()).min(1, message: 'Add at least one item');
Flod.string().email(message: 'Enter a valid email');

message: overrides i18n for that error only. The machine code is still stored for analytics.

Compose object schemas #

base.extend({'extra': Flod.string()});
base.merge(otherObjectSchema);
base.partial(deep: true);
base.pick(['id', 'email']);
base.omit(['internalDebug']);

Mask secrets in errors #

final loginSchema = Flod.object({
  'email': Flod.string().email(),
  'password': Flod.string().min(8).secret(),
  'pan': Flod.string().creditCard().secret(),
});

final failure = loginSchema.safeParse({
  'email': 'bad',
  'password': '123',
  'pan': '4111111111111111',
}) as FlodFailure;

// password / pan values are [HIDDEN] on FlodError.value
failure.errors.any((e) => e.isSecret && e.value == '[HIDDEN]');

Use .secret() on passwords, tokens, PAN, CVV, SSN, recovery codes. You can also wrap a whole object: loginSchema.secret().

Read field errors #

final failure = schema.safeParse(badData) as FlodFailure;

failure.toReadable();
// Invalid email address format.
// Must be at least 8 characters long.

failure.getFieldsMap();
// {'email': '...', 'password': '...'}

failure.getGroupedFieldsMap(); // all messages per field
failure.getMessages();         // List<String>

Deep path example:

Flod.object({'user': Flod.object({'age': Flod.int().min(18)})})
    .safeParse({'user': {'age': 10}});
// Path: 'user.age'

Harden JSON before the schema #

import 'package:flod/guard.dart';
import 'package:flod/flod.dart';

const guard = JsonGuard(
  options: JsonGuardOptions(
    maxDepth: 32,
    maxKeys: 1000,
    maxStringLength: 100000,
    maxArrayLength: 10000,
    blockPrototypeKeys: true,
  ),
);

final result = guard.parseJson(rawHttpBody, userSchema);
if (result is FlodFailure) {
  print(result.toReadable());
}

try {
  final data = guard.parseJsonOrThrow(rawHttpBody, userSchema);
} on ValidationException catch (e) {
  print(e.errors);
}

Validate Dio responses #

import 'package:flod/dio.dart' as flod_dio;
import 'package:flod/flod.dart';
import 'package:flod/guard.dart';

final dio = flod_dio.Dio();

dio.interceptors.add(
  flod_dio.FlodValidateInterceptor(
    schema: postSchema,
    guard: guard,
    extractData: (r) => (r.data as Map)['data'],
  ),
);

try {
  final response = await dio.get('/posts/1');
  // response.data is already validated (+ transformed)
} on flod_dio.DioException catch (e) {
  if (e.error is ValidationException) {
    print((e.error as ValidationException).errors);
  }
}

package:flod/dio.dart re-exports Dio — you do not need a separate dio import.

Offline helper (no HTTP):

final result = flod_dio.FlodValidateInterceptor.validatePayload(
  raw: jsonMap,
  schema: schema,
  guard: guard,
);

Drive Flutter form errors from one schema #

import 'package:flod/form.dart';

final adapter = FlodFormAdapter(signupSchema);
final fieldErrors = adapter.validate(formValues);
// {'confirmPassword': 'Passwords do not match'}

TextFormField(
  validator: adapter.fieldValidator('email', () => currentFormSnapshot),
);

FlodFormAdapter is pure Dart. Pair it with Flod.coerce.* when fields arrive as strings.

Compile a hot-path schema #

final compiled = checkoutSchema.compile();
compiled.safeParse(payload);

Use the compiled validator in request handlers after the schema is stable.

Localize errors #

FlodConfig.setup(
  localeCompiler: (code, params) {
    if (code == FlodErrorCodes.stringEmail) return 'Invalid email';
    return FlodDefaultLocale.compile(code, params);
  },
);

Table of contents #

Examples
Why Flod?
Installation
Parse API — safeParse vs parse
Schema building blocks
Coercion — Flod.coerce.*
Transform pipeline
Objects, lists & unions
Recursive schemas — Flod.lazy
Defaults, nullable & optional
Cross-field validation — refine & superRefine
Inline error messages — message:
Schema composition — Zod-style object helpers
Security & privacy — .secret()
Developer experience — readable errors
Integrations — Dio, forms & JsonGuard
Performance & benchmarks
Internationalization (i18n)
Debug mode
Project status
What's coming
Running examples & tests
License

Why Flod? #

Most Dart projects still validate API payloads with manual casts, scattered if checks, or code-gen models that assume the data is already correct. That works until it doesn't — and when it breaks, you get type 'String' is not a subtype of type 'int' in production, with no field path, no i18n hook, and sometimes leaked passwords in logs.

Flod fills the gap that Zod solved on the frontend — but natively for Dart/Flutter backends and clients, and with an integration layer built for real production concerns: network boundaries, forms, and secrets.

Capability	Manual `as` / `Map` checks	Code-gen only (JSON → class)	Flod
Zod-like chained API	❌	❌	✅
`safeParse()` / `parse()` dual API (sync + async)	❌	❌	✅
Deep path errors (`user.profile.age`)	❌	partial	✅
Transforms before validation (trim, lowerCase)	manual	❌	✅
Cross-field rules (password confirm)	manual	❌	✅
`.secret()` — mask PII in errors & traces	❌	❌	✅
JSON attack-surface guard (depth, `__proto__`)	❌	❌	✅
Dio response-validation middleware	❌	❌	✅
Flutter form field error maps	❌	❌	✅
`Flod.coerce.*` (string → int/double/bool)	manual	❌	✅
`Flod.lazy()` recursive schemas	❌	❌	✅
Inline `message:` on rules (no i18n setup)	❌	❌	✅
Compiled hot path (`schema.compile()`)	❌	❌	✅
`build_runner` typed codegen	—	✅	🔜 see roadmap

When Flod shines

API boundaries — validate jsonDecode results before they touch business logic.
Flutter forms — one schema drives server payloads and inline field errors.
Fintech / auth — .secret() on passwords, tokens, PAN, CVV.
High-throughput services — compile once, validate thousands of times per second.

Installation #

Add to pubspec.yaml:

dependencies:
  flod: ^1.1.3

Entry points

Import	Purpose
`package:flod/flod.dart`	Core validators, `Flod.` / `Flod.coerce` / `Flod.lazy`, `safeParse` / `parse`, `ValidationException`, `FlodDefaultLocale`*, `FlodConfig`, i18n
`package:flod/dio.dart`	`FlodValidateInterceptor` and a full re-export of `package:dio/dio.dart` (`Dio`, `DioException`, …) — prefer this over importing `dio` directly (no extra `dio:` line needed in your app pubspec)
`package:flod/guard.dart`	`JsonGuard` / `JsonGuardOptions` — JSON security layer
`package:flod/form.dart`	`FlodFormAdapter` — pure Dart, Flutter-ready

v1.1.0: Flod.coerce.*, Flod.lazy(), inline message:, safe withDefault / withDefaultFactory. Prefer public exports over any package:flod/src/... import.

Parse API — safeParse vs parse #

Method	On success	On failure	Use when
`safeParse(data, {abortEarly})`	`FlodSuccess<T>`	`FlodFailure<T>`	HTTP handlers, UI, anywhere you want control
`parse(data, {abortEarly})`	`T`	throws `ValidationException`	Internal trusted paths, "fail fast"
`safeParseAsync(data, {abortEarly})`	`Future<FlodSuccess<T>>`	`Future<FlodFailure<T>>`	Schemas with `.refineAsync()` / `.superRefineAsync()`
`parseAsync(data, {abortEarly})`	`Future<T>`	throws `ValidationException`	Async fail-fast

ValidationException is exported from package:flod/flod.dart (no private src/ import). Each instance exposes e.errors — a List<FlodError> with path, code, params, and value.

When abortEarly is true (or the schema used stopOnFirstError()), a multi-field object typically returns one error instead of collecting all field failures.

Schema building blocks #

Primitives #

Flod.string()          // trim, email, url, uuid, regex, creditCard (Luhn), cvv, phoneNumber, …
Flod.int()              // min, max, positive, negative, multipleOf, …
Flod.double()           // same numeric constraints
Flod.boolean()          // Zod-compatible: z.boolean() → Flod.boolean()
Flod.literal('admin')   // enum-like fixed values

String formats (domain rules) #

Flod.string().email()
Flod.string().url()
Flod.string().uuid()
Flod.string().phoneNumber()
Flod.string().creditCard()   // Luhn check
Flod.string().cvv()
Flod.string().min(8).regex(RegExp(r'[A-Z]'), code: 'needs_uppercase')
Flod.string().length(2)      // fixed length (Zod .length())

Numbers #

Flod.int().min(0).max(120)
Flod.int().positive()
Flod.int().multipleOf(7)
Flod.double().nonNegative()

Length units: string().min / .max / .length use Dart String.length (UTF-16 code units), not grapheme clusters. A single emoji like 👨‍👩‍👧‍👦 may be longer than 10.

Coercion — `Flod.coerce.*` #

Zod z.coerce.* for Dart. Coercion runs before type checks and rule chains, so the same schema can validate typed JSON and Flutter form strings.

API	Accepts (in addition to the native type)
`Flod.coerce.int()`	numeric `String` (`"42"`), other `num`, `bool` (`true`→1 / `false`→0)
`Flod.coerce.double()`	numeric `String`, `int`/`num`, `bool`
`Flod.coerce.boolean()`	`"true"`/`"false"`/`"1"`/`"0"`/`"yes"`/`"no"`/`"on"`/`"off"` (case-insensitive), `0`/`1`
`Flod.coerce.string()`	any non-null value via `Object.toString()`

Important

Use Flod.coerce.int() when input may be a String. Plain Flod.int() still rejects "42" (strict typed API / JSON that already decoded numbers).
Failed coercion → invalid_type (same as a normal type mismatch).
Chain rules as usual: Flod.coerce.int().min(0).max(120).positive().

Transform pipeline #

Transforms run before validation (Zod .transform() semantics).

Built-ins: .trim(), .toLowerCase(), .toUpperCase(), .transform(fn).

Objects, lists & unions #

Object modes #

Flod.object({'a': Flod.string()}).strict();      // unknown keys → error (anti pollution)
Flod.object({'a': Flod.string()}).passthrough(); // default — extra keys kept in output

Nested objects preserve full paths: company.department.team.lead.analytics.age.

Lists #

Flod.list(schema: Flod.int()).min(1).max(100).uniqueItems();

Union / discriminated union #

final eventSchema = Flod.union([
  Flod.object({'kind': Flod.literal('click'), 'x': Flod.int()}),
  Flod.object({'kind': Flod.literal('view'), 'duration': Flod.int()}),
]).discriminatedBy('kind'); // O(1) branch selection

Recursive schemas — `Flod.lazy` #

Deferred schema construction (Zod .lazy()). Required for trees / mutually recursive types.

Contract (exact)

Behavior	Detail
When factory runs	On first `validate` / `safeParse` (result is cached)
`compile()`	Leaves `LazyValidator` in place (does not expand) so recursive graphs do not stack-overflow
Async	`LazyValidator` implements `AsyncValidator` and forwards to an async inner when present
Secret	`Flod.lazy(() => schema).secret()` / parent `.secret()` still mask as usual

Use late final + a closure that captures the same variable.

Defaults, nullable & optional #

Modifier	Meaning
`.nullable()`	Key present, value may be `null`
`.optional()`	Key may be absent from the object
`.withDefault(value)`	When input is missing/`null` → default (Zod `.default()`)
`.withDefaultFactory(() => value)`	Same, but factory runs every time (safe for nested mutables)

Mutable defaults (lists / maps) — do this #

withDefault([]) / withDefault({}) used to share one instance across parses (silent corruption if you mutate the result). Fixed in v1.1.0:

List / Map<String, dynamic> passed to withDefault are shallow-cloned on every use.
For nested mutables, prefer an explicit factory.

Legacy aliases defaultValue(), minItems/maxItems, fixedLength() are deprecated — use withDefault(), min()/max(), length().

Cross-field validation — refine & superRefine #

.refine() / .superRefine() work on any Validator — objects and leaf primitives (Flod.string(), Flod.int(), …).

Async — use .refineAsync() / .superRefineAsync() with safeParseAsync().

Chained .refine().refine() note: nested refine wrappers short-circuit — if an inner refine fails, outer refine predicates do not run. To collect several cross-field issues in one pass, use one .superRefine() with multiple ctx.addIssue(...).

Inline error messages — `message:` #

Production apps should keep using code + FlodConfig / locale compiler. For prototypes and one-off UI copy, pass message: on rules — it overrides the i18n resolver for that error only.

Resolution order (exact):

If FlodError.message != null → that string is returned by getMessages() / toReadable() / getFieldsMap().
Else → FlodI18nResolver / localeCompiler(code, params).

code is still stored on the error (analytics, logging, later i18n). Inline message does not remove the code.

Schema composition — Zod-style object helpers #

base.extend({'extra': Flod.string()});  // add/override keys
base.merge(otherObjectSchema);          // merge two object schemas
base.partial(deep: true);               // all fields optional, recursively
base.pick(['id', 'email']);             // keep subset
base.omit(['internalDebug']);           // remove keys

Reuse primitives via SchemaPool — Flod.string() returns shared singleton instances (see Performance & benchmarks).

Security & privacy — `.secret()` #

One of Flod's strongest differentiators vs other Dart validators and vs naive Zod usage in logging pipelines.

Mark any validator (or a whole object) as secret — failed values are masked as [HIDDEN] on the structured error object (and in debug traces), instead of leaking raw PII.

Where `[HIDDEN]` appears #

Surface	Behavior
`FlodError.value` / `FlodError.toString()` / `toMap()`	`[HIDDEN]` when `isSecret: true`
`FlodDebug.trace()`	value shown as `[HIDDEN]` when the validator is secret
`toReadable()` / `getFieldsMap()` / `getMessages()`	human messages only — never embed the raw failed value (secret or not)

So masking is checked on the error object, not by grepping toReadable() for the string HIDDEN.

Example: public vs secret on `FlodError.value` #

Input: {'email': 'bad', 'password': '123'}

Public field (password without .secret()):

FlodError(path: 'password', code: string_min, ..., value: 123)

Secret field (same rule + .secret()):

FlodError(path: 'password', code: string_min, ..., value: [HIDDEN])

No accidental password/token/card leaks in:

FlodError.value (returns [HIDDEN] when secret)
FlodError.toString() / toMap()
FlodDebug.trace() when isSecret: true

Use .secret() on: passwords, refresh tokens, API keys, PAN, CVV, SSN, recovery codes.

Developer experience — readable errors #

Every error carries:

path — FlodPath with .toReadable() → object keys dotted, list indices in brackets: profile.tags[0], items[1].qty
code — stable machine id (FlodErrorCodes.*) for i18n
params — interpolation payload for translators

Tree-style logging (from stress example) #

   ❌ PUBLIC FAIL → 3 error(s)
         ↳ Path: 'profile.displayName' | Code: string_min      | Value: A
         ↳ Path: 'items[1].qty'        | Code: number_positive | Value: -1
         ↳ Path: 'email'               | Code: string_email    | Value: not-an-email

Integrations — Dio, forms & JsonGuard #

JsonGuard — secure JSON ingestion #

Structural security before schema validation. Blocks: prototype pollution keys, excessive depth/key budget, oversized strings/arrays, invalid JSON.

Method	On failure
`parseJson` / `guard`	returns `FlodFailure` (does not throw)
`parseJsonOrThrow`	throws `ValidationException`

Already-decoded JSON: guard.guard(decoded, schema).

FlodValidateInterceptor — Dio middleware #

Do not add a separate import 'package:dio/dio.dart' just to use Flod's interceptor. package:flod/dio.dart already re-exports Dio (Dio, DioException, …). That also avoids the depend_on_referenced_packages analyzer warning that appears when an app imports dio directly without declaring it in its own pubspec.yaml.

You only need flod in your pubspec.yaml — dio is pulled in transitively by Flod. Declare dio yourself only if your app uses Dio outside of Flod and you want a direct dependency.

On success: replaces response.data with validated, typed output. On failure (interceptor path): rejects with DioException whose error is a ValidationException.

FlodFormAdapter — form bridge #

Pure Dart — no Flutter dependency required at the adapter level. Built directly on top of getFieldsMap(), so form errors and API errors always stay in sync with the same schema.

Performance & benchmarks #

Flod v1.0 ships a performance layer designed for hot paths:

Layer	What it does
SchemaPool	Shared singleton validators for `string`, `int`, `double`, `bool`
Chain optimization	Identity-aware `copyWith`, `isPure` fast path, secret hoisting
ValidatorCompiler	`schema.compile()` → `CompiledObjectValidator` / `CompiledListValidator`, identity cache

Methodology (internal QA, July 2026) #

Benchmarks were run outside the published package (not shipped to pub.dev) using:

Warm compiled schema (buildSchema().compile() once, then parse in a loop)
Checkout-like schema: nested objects, email(), trim(), uniqueItems(), defaults
Payloads ~1 KB / ~100 KB / ~1 MB (scaled via items[])
Percentile harness: 2 000 warmup + 20 000 timed iterations
Comparison vs a manual cast baseline (same field access, no validation)

Environment: Dart JIT release-mode script (not IDE debugger). For absolute numbers, run your own profile with dart run --define=dart.vm.product=true on target hardware.

Results summary (representative run, post Map-copy optimization) #

Scenario	Flod WARM median	Notes
1 KB payload	~6 µs	Full validation + transforms + paths
Manual baseline 1 KB	~1 µs	Casts only — shows "feature tax"
Overhead ratio	~6×	Regex, trim, uniqueItems, path tracking
100 KB payload	~465 µs	Dominated by list item validation
1 MB payload	~7.5 ms	Linear with item count

CPU profile insight (DevTools, 20k × 1 KB):

Dominant cost was LinkedHashMap operations from defensive Map.from() per object level — fixed in v1.0 by read-only source access on the compiled path.
FlodPath.append was ~1% self-time — not the bottleneck.
GC pauses were not correlated with 1 KB outlier spikes (likely scheduler / JIT tiering).

Cold compile: first schema.compile() ≈ 25 µs (one-time startup cost).

Compiled vs raw parity: 100+ iteration stress tests confirm identical semantics between compiled and non-compiled validators.

final hot = productionSchema.compile();
hot.safeParse(apiPayload); // use this in request handlers

Internationalization (i18n) #

Errors are code + params — text lives in a resolver, not hard-coded in validators.

FlodDefaultLocale (built-in English compiler) and FlodErrorCodes are exported from package:flod/flod.dart (v1.0.3+ — no private src/ import).

Built-in English: FlodDefaultLocale.compile. Custom factory: Flod.i18n(yourCompiler).

Debug mode #

FlodConfig.setup(
  debug: true,
  onTrace: (msg) => log.info(msg), // optional custom sink
);

Trace format:

[Flod] [ok] StringValidator @ profile.displayName → Pro User
[Flod] [fail] IntValidator @ user.age → [HIDDEN] (1 error(s))  // when .secret()

Project status #

Flod v1.1 adds the form/API “first week” gaps (coerce, lazy, inline messages, safe defaults) on top of the v1.0 engine:

✅ Core parsing (safeParse / parse, sync & async, optional abortEarly)
✅ Public ValidationException + FlodDefaultLocale on the main export
✅ Full primitive + string-format validator suite (email, url, uuid, phone, credit card/Luhn, CVV, regex)
✅ Flod.coerce.int/double/boolean/string — stringly form/JSON → typed values
✅ Flod.lazy(() => schema) — recursive / mutually recursive schemas
✅ Inline message: on rules + refine (bypasses i18n when set)
✅ withDefault / withDefaultFactory — mutable defaults no longer shared across parses
✅ Transform pipeline, nullable/optional
✅ Objects (strict/passthrough), nested paths (items[1].qty), lists, unions & discriminated unions
✅ Cross-field and leaf validation (refine, superRefine, async variants)
✅ Schema composition (extend, merge, partial, pick, omit)
✅ .secret() PII masking across errors and debug traces
✅ i18n resolver + debug tracing
✅ Performance layer — SchemaPool, ChainOptimization, ValidatorCompiler
✅ Integrations — JsonGuard, FlodValidateInterceptor (Dio re-export), FlodFormAdapter

The only major item intentionally deferred is typed static codegen (build_runner) — see below.

What's coming #

New APIs stay additive (Flod.coerce.*, Flod.lazy, message:) — existing call sites keep compiling.

Confirmed roadmap #

Static codegen — opt-in build_runner packages (flod_generator, flod_build): annotate a class with @FlodSchema(), get a typed Validator<T>, parse helpers, and refactor-safe field paths. Runtime-only Flod remains fully supported and will not be deprecated.
Network — .isIp(version: IpVersion) (IPv4 / IPv6), .isHostname() (RFC domain names), .isPort() (0–65535).
Media & encoding — .isBase64() (optional strict padding), .isMimeType() (type/subtype, e.g. application/json).
Advanced formats — .isIso8601() (date, time, duration), .isJsonString() (valid JSON object/array in a string), .isHexColor() (#RRGGBB / #RRGGBBAA).
Content & business rules — .isSlug() (URL-safe slugs), .isCurrencyCode() (ISO 4217), .isLanguageCode() (ISO 639-1).

Proposed additions (under evaluation) #

.toJsonSchema() / .toOpenApiSchema() — export any Flod schema as JSON Schema / OpenAPI.
Flod.record / Flod.enum_ / .catch() / .describe() — open maps, Dart enum sugar, soft fallbacks, schema metadata.
schema.generateSample() — fixture data from a schema.
Isolate-aware compile(parallel: true) — niche 1 MB+ Flutter UI-thread offload.
CompiledListValidator completion — internal compiler consistency for lists.

Track progress in CHANGELOG.

Running examples & tests #

cd flod
dart pub get
dart test                            # 95+ tests — core, integrations, performance, v1.1 features
dart run example/flod_example.dart   # quick start & privacy demos

License #

See LICENSE.

flod 1.1.3 flod: ^1.1.3 copied to clipboard

Metadata