Struct ValueCodec 

pub struct ValueCodec;

Protocol-agnostic value coercion utilities. Centralizes scaling, rounding, clamping, and common string/boolean parsing.

Implementations

impl ValueCodec

pub fn logical_to_wire_value( value: &NGValue, logical_dt: DataType, wire_dt: DataType, t: &Transform, ) -> DriverResult<NGValue>

pub fn wire_to_logical_value( value: &NGValue, wire_dt: DataType, logical_dt: DataType, t: &Transform, ) -> DriverResult<NGValue>

Coerce a wire-layer NGValue into a logical-layer NGValue (uplink).

Design goal

Keep driver code aligned with existing coerce_*_to_value APIs while enforcing a single, consistent uplink policy:

• Decode protocol payload into a wire NGValue that matches wire_dt
• Then call this function once to apply Transform and box into logical_dt

Safety policy (important)

When a non-identity numeric transform is configured, this conversion requires an f64 intermediate. For 64-bit integers beyond (2^{53}), f64 cannot represent all integers exactly. To avoid silent corruption, we reject such cases.

pub fn apply_transform_f64(x: f64, t: &Transform) -> f64

pub fn coerce_bool_to_value( value: bool, expected: DataType, t: &Transform, ) -> Option<NGValue>

Apply optional numeric transform and return an NGValue in the expected DataType.

Notes

• This is the recommended hot-path conversion API for drivers.
• Timestamp/Binary require protocol-specific parsing and are not supported here.

pub fn coerce_f64_to_value( value: f64, expected: DataType, t: &Transform, ) -> Option<NGValue>

Coerce a numeric value (f64) into an expected DataType with optional transform.

Performance

This avoids serde_json::Value allocations and should be used in hot paths.

pub fn coerce_u64_to_value( value: u64, expected: DataType, t: &Transform, ) -> Option<NGValue>

Coerce an unsigned integer source into an expected DataType with optional transform.

Performance & correctness

• When scale is None and the target is an integer type, this avoids any f64 roundtrip and therefore preserves full integer precision.
• When scale is Some(_), we apply scaling in f64 and then delegate to coerce_f64_to_value for consistent rounding behavior.

pub fn coerce_i64_to_value( value: i64, expected: DataType, t: &Transform, ) -> Option<NGValue>

Coerce a signed integer source into an expected DataType with optional transform.

See coerce_u64_to_value for performance semantics.

pub fn time_of_day_to_ms(t: NaiveTime) -> u64

Time helpers: centralize rendering to string or epoch-ms conversions for drivers.

pub fn duration_to_ms(d: Duration) -> i64

pub fn date_to_epoch_ms(d: NaiveDate) -> Option<i64>

pub fn datetime_to_epoch_ms(ndt: NaiveDateTime) -> i64

pub fn bytes_to_hex_string(bytes: &[u8]) -> String

Convert a byte slice into a lower-case hex string with “0x” prefix.

pub fn hex_string_to_bytes(s: &str) -> Option<Vec<u8>>

Decode a hex string into bytes. Accepts optional “0x”/“0X” prefix and odd length (pads low nibble with 0).

pub fn json_to_timestamp_ms(v: &Value) -> Option<i64>

Parse a JSON value as epoch milliseconds (UTC).

• String: RFC3339 parsed in any offset, converted to UTC ms
• Number: treated as epoch milliseconds