Go modules

github.com/go-ozzo/ozzo-validation/v4

• Last release 18 days ago

  27 Oct 2026

• Ships unpredictably

  gaps range from 8 days to 5.8 years

• Most releases are documented

  notes for 8 of 9 stable releases

• Nothing withdrawn

  no release was ever pulled

• 7 years old

  23 releases · first in 2020

1. v4.5.027 Oct 2026Security3 sources agree

   …on the latest release by design so that the vulnerability data is current. One required check, "Test", gates all jobs.

   This release restores the v4.3.0 behavior that v4.4.0 changed for empty values. It adds explicit opt-ins for the
   cases v4.4.0 was meant to fix, and fixes the problems found in the unreleased changes before they ship.

   Fixed

   • Restore the v4.3.0 empty-value semantics (#234, reported
     by @ldez). Two "Breaking Changes" of v4.4.0 are reverted:

     • a zero struct is no longer empty: only the zero time.Time is. This applies to every rule that checks for
       empty values. Required and NilOrNotEmpty pass again for a zero struct, and Required on a zero
       Validatable struct reports the struct's own field errors instead of "cannot be blank". Empty reports a zero
       struct as not empty again, and the rules that skip empty values (In, NotIn, Length, RuneLength, Date
       and the string rules, including is.*) validate a zero struct again. Each(Required) passes again for
       zero-struct elements;
     • Min()/Max() skip empty values again (0, 0.0, the zero time.Time), as their documentation says.

     To keep the v4.4 checks, use the new opt-ins below.

   • Errors.Error() no longer starts with "; " when the first sorted key holds a nil error. An Errors with only
     nil entries returns "", as an empty Errors does.

   • is.Latitude/is.Longitude are validation.StringRule again, as in v4.4.1, so code that holds them as a
     StringRule compiles. String input is validated exactly as in v4.4.1: "NaN", "1e1", "0x1p-2", "45." and
     ".5" are rejected. Numbers are accepted as introduced by
     #223; NaN and infinities are rejected.

   • A missing map key never runs its rules with a nil value: rules written for the key's type, such as a By with a
     type assertion, no longer panic. The error stays "required key is missing" (validation_key_missing). Only a
     Required or NotNil rule with a custom message (Error/ErrorObject) reports its own error
     (#222 by
     @nguyenvantuan2391996, narrowed) — fixes
     #134.

   • EnsureString(nil) returns an error instead of panicking
     (#232 by @yuefdev) — fixes
     #233.

   • MultipleOf(0) returns an error instead of panicking with a division by zero
     (#231 by @SashaMIT);
     MultipleOf(nil) returns an error instead of panicking.

   • NotIn() compares with reflect.DeepEqual, as In() does: it no longer panics on uncomparable values such as
     []byte, and structs with pointer fields compare by the pointed-to values
     (#229 by @youdie006).

   Added

   • ozzo_validation_no_template build tag: error messages are rendered without text/template, which removes it
     from the binary and makes it noticeably smaller. Built-in messages read the same; custom messages support only
     field placeholders such as {{.min}} and {{ .min }}. See the README
     (#235 by @ldez) — fixes
     #230.

   • ThresholdRule.ValidateEmpty(): Min/Max also check empty values, e.g. Min(0).Exclusive().ValidateEmpty()
     rejects 0 (#165,
     #180).

   • EmptyChecker interface: a struct type defines when its value is empty
     (#143).

   • StringRule.AllowNumber(): a string rule can also accept finite numbers.

   • is.Latitude/is.Longitude accept numbers (int, uint and float types)
     (#223 by
     @nguyenvantuan2391996) — fixes
     #185.

   • DateRule.Location(): parse dates that carry no time zone in a given location; the default stays UTC
     (#220 by
     @nguyenvantuan2391996) — fixes
     #166.

   • Errors.Is: errors.Is finds a matching error anywhere in validation.Errors, including nested maps, slices and
     structs (#225 by
     @ChrisJr404) — fixes #116.

     #225 also proposed Errors.As. It is not part of this release. With it, errors.As(err, &validation.Error)
     returned the first field's error for a map of field errors, and code that uses that call to tell a single error from
     a field map lost the field names. errors.As keeps reporting false for validation.Errors; use errors.Is or
     Flatten() to reach the individual errors.

   • ErrorObject.Is: a validation error matches a built-in error with the same code, so
     errors.Is(err, validation.ErrRequired) works, also for rules with a custom message such as
     Required.Error("..."). Give the sentinel errors of your own rules a code: an error with an empty code never
     matches.

   • Flatten(err), Errors.Flatten() and FieldError: a flat, sorted list of all field errors with the key path,
     code, rendered message and params, and the error itself in Err. Field() gives items.0.name, Pointer() gives
     the RFC 6901 pointer /items/0/name. Slice indexes sort numerically (items.2 before items.10). A single error
     that is not an Errors is one entry with no path. Check Err for an InternalError before sending Message to a
     client.

   • errors.Is and errors.As reach the error wrapped by NewInternalError.

   • README: "Empty Values", "Checking for an Error", "Listing Field Errors" and "Smaller Binaries" sections.

   Changed

   • Go 1.21 or later is required (go 1.21 in go.mod), the minimum announced in
     #207.
   • is.CurrencyCode uses an ISO 4217 list maintained in this module instead of govalidator's, which adds current
     codes such as VES and VED (#224 by
     @nguyenvantuan2391996) — fixes
     #206.
   • testify v1.4.0 → v1.12.1 (test-only).
   • CI tests Go 1.21, oldstable and stable on Linux, and stable on Windows and macOS, with the race detector, with and
     without the ozzo_validation_no_template tag. It also builds and tests on 386, checks formatting and
     go mod tidy, and pins every tool version except govulncheck, which stays on the latest release by design so that
     the vulnerability data is current. One required check, "Test", gates all jobs.
   • Docs: the v4.4.0 behavior changes documented
     (#228 by @dw-kihara);
     updated in this release for the restored semantics.
   • Tests: coverage gaps closed (#218 by
     @nguyenvantuan2391996).
   • The committed coverage.out is removed; test outputs are ignored.

   Install

   go get github.com/go-ozzo/ozzo-validation/v4@v4.5.0

   Full changelog: v4.4.1...v4.5.0

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