Struct CdcEnvelope 

pub struct CdcEnvelope<T> {
    pub op: String,
    pub ts_ms: i64,
    pub source: CdcSource,
    pub before: Option<T>,
    pub after: Option<T>,
}

CDC envelope for sink serialization.

Compatible with Debezium envelope format for interoperability with downstream systems (Kafka Connect, data lakes, etc.).

Debezium Operation Codes

• "c": Create (insert)
• "u": Update
• "d": Delete
• "r": Read (snapshot)

Example

use laminar_core::operator::changelog::{CdcEnvelope, CdcSource};
use serde_json::json;

let source = CdcSource::new("laminardb", "default", "orders");

// Insert
let insert = CdcEnvelope::insert(json!({"id": 1, "amount": 100}), source.clone(), 1000);
assert_eq!(insert.op, "c");

// Delete
let delete = CdcEnvelope::delete(json!({"id": 1}), source.clone(), 2000);
assert_eq!(delete.op, "d");

// Update
let update = CdcEnvelope::update(
    json!({"id": 1, "amount": 100}),
    json!({"id": 1, "amount": 150}),
    source,
    3000,
);
assert_eq!(update.op, "u");

Fields

op: String

Operation type: “c” (create), “u” (update), “d” (delete), “r” (read/snapshot)

ts_ms: i64

Timestamp in milliseconds since epoch

source: CdcSource

Source metadata

before: Option<T>

Value before change (for updates/deletes)

after: Option<T>

Value after change (for inserts/updates)

Implementations

impl<T> CdcEnvelope<T>

pub fn insert(after: T, source: CdcSource, ts_ms: i64) -> Self

Creates an insert (create) envelope.

pub fn delete(before: T, source: CdcSource, ts_ms: i64) -> Self

Creates a delete envelope.

pub fn update(before: T, after: T, source: CdcSource, ts_ms: i64) -> Self

Creates an update envelope.

pub fn read(after: T, source: CdcSource, ts_ms: i64) -> Self

Creates a read (snapshot) envelope.

pub fn is_insert(&self) -> bool

Returns true if this is an insert operation.

pub fn is_delete(&self) -> bool

Returns true if this is a delete operation.

pub fn is_update(&self) -> bool

Returns true if this is an update operation.

pub fn weight(&self) -> i32

Returns the Z-set weight for this operation.

• Insert/Read: +1
• Delete: -1
• Update: 0 (net effect of -1 for before + +1 for after)

impl<T: Serialize> CdcEnvelope<T>

pub fn to_json(&self) -> Result<String, Error>

Serializes the envelope to JSON.

Errors

Returns an error if serialization fails.

pub fn to_json_pretty(&self) -> Result<String, Error>

Serializes the envelope to pretty-printed JSON.

Errors

Returns an error if serialization fails.

pub fn to_json_bytes(&self) -> Result<Vec<u8>, Error>

Serializes the envelope to JSON bytes.

Errors

Returns an error if serialization fails.

Trait Implementations

impl<T: Clone> Clone for CdcEnvelope<T>

fn clone(&self) -> CdcEnvelope<T>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for CdcEnvelope<T>

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

Formats the value using the given formatter.

impl<'de, T> Deserialize<'de> for CdcEnvelope<T>

where T: Deserialize<'de>,

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<T> Serialize for CdcEnvelope<T>

where T: Serialize,

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.