Struct FromJsonConfig 

pub struct FromJsonConfig {
    pub default_type_name: String,
    pub version: (u32, u32),
    pub max_depth: Option<usize>,
    pub max_array_size: Option<usize>,
    pub max_string_length: Option<usize>,
    pub max_object_size: Option<usize>,
    pub surrogate_policy: SurrogatePolicy,
    pub lenient: bool,
}

Configuration for JSON import

Controls how JSON is converted to HEDL, including security limits to prevent denial-of-service attacks from malicious inputs.

High Default Limits

The default limits are set intentionally high to handle large-scale data processing scenarios common in ML/AI applications:

• 10,000 depth: Deep nesting in complex hierarchical data
• 10,000,000 array size: Large datasets and batches
• 100 MB string length: Base64-encoded binary data, embeddings
• 100,000 object size: Rich metadata and configuration objects

These defaults prioritize functionality over restrictiveness. For untrusted input, consider using the builder pattern with custom limits.

Examples

use hedl_json::FromJsonConfig;

// Default configuration with high limits for ML/data workloads
let config = FromJsonConfig::default();

// Custom configuration using builder pattern
let custom_config = FromJsonConfig::builder()
    .max_depth(1_000)
    .max_array_size(100_000)
    .max_string_length(10 * 1024 * 1024) // 10 MB
    .build();

// Strict configuration for untrusted input
let strict_config = FromJsonConfig::builder()
    .max_depth(50)
    .max_array_size(10_000)
    .max_string_length(1_000_000)
    .max_object_size(1_000)
    .build();

// Unlimited configuration (use with caution)
let unlimited_config = FromJsonConfig::builder()
    .unlimited()
    .build();

Fields

default_type_name: String

Default type name for arrays without metadata

version: (u32, u32)

HEDL version to use

max_depth: Option<usize>

Maximum recursion depth (default: 10,000)

Prevents stack overflow from deeply nested JSON structures. Set to None to disable (not recommended for untrusted input).

max_array_size: Option<usize>

Maximum array size (default: 10,000,000)

Prevents memory exhaustion from extremely large arrays. JSON arrays can contain large datasets, batches, or embeddings. Set to None to disable (not recommended for untrusted input).

max_string_length: Option<usize>

Maximum string length (default: 100 MB)

Prevents memory exhaustion from extremely large strings. JSON strings often contain base64-encoded binary data, large text fields, or embedded documents requiring high limits. Set to None to disable (not recommended for untrusted input).

max_object_size: Option<usize>

Maximum object size (default: 100,000)

Prevents memory exhaustion from objects with many keys. Configuration files and metadata-rich objects can have many properties. Set to None to disable (not recommended for untrusted input).

surrogate_policy: SurrogatePolicy

Policy for handling unpaired UTF-16 surrogates

Some systems emit JSON with unpaired surrogates (e.g., truncated JavaScript strings). This setting controls how to handle them.

Default: SurrogatePolicy::Reject (strict validation)

lenient: bool

Enable lenient JSON parsing (JSON5-style trailing commas and comments)

When enabled, the parser accepts:

• Trailing commas in arrays and objects
• Single-line (//) and multi-line (/* */) comments

Requires the lenient feature flag.

Default: false (strict RFC 8259 JSON)

Implementations

impl FromJsonConfig

pub fn builder() -> FromJsonConfigBuilder

Create a new builder for configuring JSON import

Examples

use hedl_json::FromJsonConfig;

let config = FromJsonConfig::builder()
    .max_depth(1_000)
    .max_array_size(100_000)
    .build();

Trait Implementations

impl Clone for FromJsonConfig

fn clone(&self) -> FromJsonConfig

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for FromJsonConfig

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for FromJsonConfig

fn default() -> Self

Returns the “default value” for a type.

impl ImportConfig for FromJsonConfig

fn default_type_name(&self) -> &str

Get the default type name for collections without explicit metadata.

fn version(&self) -> (u32, u32)

Get the HEDL version to use for the imported document.