Struct ZString 

pub struct ZString { /* private fields */ }

Schema for string validation. Created via vld::string().

Example

use vld::prelude::*;

let schema = vld::string().min(3).max(20).email();

Implementations

impl ZString

pub fn new() -> ZString

pub fn type_error(self, msg: impl Into<String>) -> ZString

Set a custom error message for type mismatch (when the input is not a string).

Example

use vld::prelude::*;
let schema = vld::string().type_error("Must be text!");
let err = schema.parse("42").unwrap_err();
assert!(err.issues[0].message.contains("Must be text!"));

pub fn with_messages<F>(self, f: F) -> ZString

where F: Fn(&str) -> Option<String>,

Override error messages in bulk by check key.

The closure receives the check key (e.g. "too_small", "invalid_email") and should return Some(new_message) to replace, or None to keep the original.

Available keys: "too_small", "too_big", "invalid_length", "invalid_email", "invalid_url", "invalid_uuid", "invalid_regex", "invalid_starts_with", "invalid_ends_with", "invalid_contains", "non_empty", "invalid_ipv4", "invalid_ipv6", "invalid_base64", "invalid_iso_date", "invalid_iso_datetime", "invalid_iso_time", "invalid_hostname", "invalid_cuid2", "invalid_ulid", "invalid_nanoid", "invalid_emoji".

Example

use vld::prelude::*;
let schema = vld::string().min(3).email()
    .with_messages(|key| match key {
        "too_small" => Some("Too short!".into()),
        "invalid_email" => Some("Bad email!".into()),
        _ => None,
    });

pub fn min(self, len: usize) -> ZString

Minimum string length (inclusive).

pub fn min_msg(self, len: usize, msg: impl Into<String>) -> ZString

Minimum string length with custom message.

pub fn max(self, len: usize) -> ZString

Maximum string length (inclusive).

pub fn max_msg(self, len: usize, msg: impl Into<String>) -> ZString

Maximum string length with custom message.

pub fn len(self, len: usize) -> ZString

Exact string length.

pub fn len_msg(self, len: usize, msg: impl Into<String>) -> ZString

Exact string length with custom message.

pub fn email(self) -> ZString

Must be a valid email address.

pub fn email_msg(self, msg: impl Into<String>) -> ZString

Must be a valid email address, with custom message.

pub fn url(self) -> ZString

Must be a valid URL (http/https).

pub fn url_msg(self, msg: impl Into<String>) -> ZString

Must be a valid URL, with custom message.

pub fn uuid(self) -> ZString

Must be a valid UUID.

pub fn uuid_msg(self, msg: impl Into<String>) -> ZString

Must be a valid UUID, with custom message.

pub fn starts_with(self, prefix: impl Into<String>) -> ZString

Must start with the given prefix.

pub fn starts_with_msg( self, prefix: impl Into<String>, msg: impl Into<String>, ) -> ZString

Must start with the given prefix, with custom message.

pub fn ends_with(self, suffix: impl Into<String>) -> ZString

Must end with the given suffix.

pub fn ends_with_msg( self, suffix: impl Into<String>, msg: impl Into<String>, ) -> ZString

Must end with the given suffix, with custom message.

pub fn contains(self, sub: impl Into<String>) -> ZString

Must contain the given substring.

pub fn contains_msg( self, sub: impl Into<String>, msg: impl Into<String>, ) -> ZString

Must contain the given substring, with custom message.

pub fn non_empty(self) -> ZString

Must not be empty.

pub fn non_empty_msg(self, msg: impl Into<String>) -> ZString

Must not be empty, with custom message.

pub fn trim(self) -> ZString

Trim whitespace before validation.

pub fn to_lowercase(self) -> ZString

Convert to lowercase before validation.

pub fn to_uppercase(self) -> ZString

Convert to uppercase before validation.

pub fn coerce(self) -> ZString

Coerce non-string values (numbers, booleans) to string.

pub fn ipv4(self) -> ZString

Must be a valid IPv4 address.

pub fn ipv4_msg(self, msg: impl Into<String>) -> ZString

Must be a valid IPv4 address, with custom message.

pub fn ipv6(self) -> ZString

Must be a valid IPv6 address.

pub fn ipv6_msg(self, msg: impl Into<String>) -> ZString

Must be a valid IPv6 address, with custom message.

pub fn base64(self) -> ZString

Must be a valid Base64 string.

pub fn base64_msg(self, msg: impl Into<String>) -> ZString

Must be a valid Base64 string, with custom message.

pub fn iso_date(self) -> ZString

Must be a valid ISO 8601 date (YYYY-MM-DD).

pub fn iso_date_msg(self, msg: impl Into<String>) -> ZString

Must be a valid ISO 8601 date, with custom message.

pub fn iso_datetime(self) -> ZString

Must be a valid ISO 8601 datetime.

pub fn iso_datetime_msg(self, msg: impl Into<String>) -> ZString

Must be a valid ISO 8601 datetime, with custom message.

pub fn iso_time(self) -> ZString

Must be a valid ISO 8601 time (HH:MM or HH:MM:SS).

pub fn iso_time_msg(self, msg: impl Into<String>) -> ZString

Must be a valid ISO 8601 time, with custom message.

pub fn hostname(self) -> ZString

Must be a valid hostname.

pub fn hostname_msg(self, msg: impl Into<String>) -> ZString

Must be a valid hostname, with custom message.

pub fn cuid2(self) -> ZString

Must be a valid CUID2 string (lowercase alphanumeric, starts with a letter).

pub fn cuid2_msg(self, msg: impl Into<String>) -> ZString

Must be a valid CUID2 string, with custom message.

pub fn ulid(self) -> ZString

Must be a valid ULID (26-char Crockford Base32).

pub fn ulid_msg(self, msg: impl Into<String>) -> ZString

Must be a valid ULID, with custom message.

pub fn nanoid(self) -> ZString

Must be a valid Nano ID (alphanumeric + _ + -).

pub fn nanoid_msg(self, msg: impl Into<String>) -> ZString

Must be a valid Nano ID, with custom message.

pub fn emoji(self) -> ZString

Must contain at least one emoji character.

pub fn emoji_msg(self, msg: impl Into<String>) -> ZString

Must contain an emoji, with custom message.

Trait Implementations

impl Clone for ZString

fn clone(&self) -> ZString

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Default for ZString

fn default() -> ZString

Returns the “default value” for a type.

impl VldSchema for ZString

type Output = String

The Rust type produced by this schema after successful parsing.

fn parse_value(&self, value: &Value) -> Result<String, VldError>

Parse and validate a serde_json::Value.

fn parse<I>(&self, input: &I) -> Result<Self::Output, VldError>

where I: VldInput + ?Sized,

Parse from any supported input (JSON string, file path, serde_json::Value, etc.)

fn validate<T>(&self, value: &T) -> Result<Self::Output, VldError>

where T: Serialize,

Validate an existing Rust value against this schema.

fn is_valid<T>(&self, value: &T) -> bool

where T: Serialize,

Check if an existing Rust value passes this schema’s validation.

fn optional(self) -> ZOptional<Self>

Make this field optional. Missing or null values become None.

fn nullable(self) -> ZNullable<Self>

Allow null values. Null becomes None.

fn with_default(self, value: Self::Output) -> ZDefault<Self>

where Self::Output: Clone,

Provide a default value when the field is missing or null.

fn refine<F>(self, check: F, message: &str) -> ZRefine<Self, F>

where F: Fn(&Self::Output) -> bool,

Add a custom refinement check without changing the output type.

fn transform<F, U>(self, f: F) -> ZTransform<Self, F, U>

where F: Fn(Self::Output) -> U,

Transform the output value after successful parsing.

fn nullish(self) -> ZNullish<Self>

Make this field nullish (both optional and nullable).

fn catch(self, fallback: Self::Output) -> ZCatch<Self>

where Self::Output: Clone,

Return a fallback value on ANY validation error.

fn pipe<S>(self, next: S) -> ZPipe<Self, S>

where S: VldSchema, Self::Output: Serialize,

Chain this schema’s output into another schema.

fn describe(self, description: &str) -> ZDescribe<Self>

Attach a human-readable description/label to this schema.

fn super_refine<F>(self, check: F) -> ZSuperRefine<Self, F>

where F: Fn(&Self::Output, &mut VldError),

Add a custom refinement that can produce multiple errors.

fn or<B>(self, other: B) -> ZUnion2<Self, B>

where B: VldSchema,

Create a union: this schema or another. Returns Either<Self::Output, B::Output>.

fn and<B>(self, other: B) -> ZIntersection<Self, B>

where B: VldSchema,

Create an intersection: input must satisfy both schemas.

fn message(self, msg: impl Into<String>) -> ZMessage<Self>

Override the error message for this schema.