https://docs.rs/databricks-zerobus-ingest-sdk

Zerobus Rust SDK

A high-performance Rust client for streaming data ingestion into Databricks Delta tables using the Zerobus service.

Disclaimer

Public Preview: This SDK is supported for production use cases and is available to all customers. Databricks is actively working on stabilizing the Zerobus Ingest SDK for Rust. Minor version updates may include backwards-incompatible changes.

We are keen to hear feedback from you on this SDK. Please file issues, and we will address them.

Table of Contents

• Overview
• Features
• Installation
• Quick Start
• Repository Structure
• How It Works
• Usage Guide
  • 1. Generate Protocol Buffer Schema
  • 2. Initialize the SDK
  • 3. Configure Authentication
  • 4. Create a Stream
  • 5. Ingest Data
  • 6. Handle Acknowledgments
  • 7. Close the Stream
• Configuration Options
• Error Handling
• Examples
• Best Practices
• API Reference
• Building from Source
• Community and Contributing
• License

Overview

The Zerobus Rust SDK provides a robust, async-first interface for ingesting large volumes of data into Databricks Delta tables. It abstracts the complexity of the Zerobus service and handles authentication, retries, stream recovery, and acknowledgment tracking automatically.

What is Zerobus? Zerobus is a high-throughput streaming service for direct data ingestion into Databricks Delta tables, optimized for real-time data pipelines and high-volume workloads.

Features

• Async/Await Support - Built on Tokio for efficient concurrent I/O operations
• Automatic OAuth 2.0 Authentication - Seamless token management with Unity Catalog
• Built-in Recovery - Automatic retry and reconnection for transient failures
• High Throughput - Configurable inflight record limits for optimal performance
• Batch Ingestion - Ingest multiple records at once with all-or-nothing semantics for maximum throughput
• Flexible Serialization - Support for both JSON (simple) and Protocol Buffers (type-safe) data formats
• Type Safety - Protocol Buffers ensure schema validation at compile time
• Schema Generation - CLI tool to generate protobuf schemas from Unity Catalog tables
• Flexible Configuration - Fine-tune timeouts, retries, and recovery behavior
• Graceful Stream Management - Proper flushing and acknowledgment tracking

Installation

Add the SDK to your Cargo.toml:

cargo add databricks-zerobus-ingest-sdk
cargo add prost prost-types
cargo add tokio --features macros,rt-multi-thread

Why these dependencies?

• databricks-zerobus-ingest-sdk - The SDK itself
• prost and prost-types - Required for encoding your data to Protocol Buffers and loading schema descriptors
• tokio - Async runtime required for running async functions (the SDK is fully async)

What's in the crates.io package? The published crate contains only the core Zerobus ingestion SDK. Tools for schema generation (tools/generate_files) and working examples (examples/) are only available in the GitHub repository. You'll need to clone the repo to generate protobuf schemas from your Unity Catalog tables.

For Local Development

Clone the repository and use a path dependency:

git clone https://github.com/databricks/zerobus-sdk-rs.git
cd your_project

Then in your Cargo.toml:

[dependencies]
databricks-zerobus-ingest-sdk = { path = "../zerobus-sdk-rs/sdk" }
prost = "0.13.3"
prost-types = "0.13.3"
tokio = { version = "1.42.0", features = ["macros", "rt-multi-thread"] }

Quick Start

The SDK supports two serialization formats and two ingestion methods:

Serialization:

• JSON (Recommended for getting started): Simpler approach using JSON strings, no schema generation required
• Protocol Buffers (Recommended for production): Type-safe approach with schema validation at compile time

Ingestion Methods:

• Single-record (ingest_record): Ingest records one at a time with per-record acknowledgment
• Batch (ingest_records): Ingest multiple records at once with all-or-nothing semantics for higher throughput

See examples/README.md for detailed setup instructions and examples for all combinations.

Repository Structure

zerobus_rust_sdk/
├── sdk/                                # Core SDK library
│   ├── src/
│   │   ├── lib.rs                      # Main SDK and stream implementation
│   │   ├── default_token_factory.rs    # OAuth 2.0 token handling
│   │   ├── errors.rs                   # Error types and retryable logic
│   │   ├── headers_provider.rs         # Trait for custom authentication headers
│   │   ├── stream_configuration.rs     # Stream options
│   │   ├── landing_zone.rs             # Inflight record buffer
│   │   └── offset_generator.rs         # Logical offset tracking
│   ├── zerobus_service.proto           # gRPC protocol definition
│   ├── build.rs                        # Build script for protobuf compilation
│   └── Cargo.toml
│
├── tools/
│   └── generate_files/                 # Schema generation CLI tool
│       ├── src/
│       │   ├── main.rs                 # CLI entry point
│       │   └── generate.rs             # Unity Catalog -> Proto conversion
│       ├── README.md                   # Tool documentation
│       └── Cargo.toml
│
├── examples/
│   ├── README.md                       # Examples documentation
│   ├── basic_example_json/             # JSON single-record example
│   │   ├── src/main.rs                 # Example usage code
│   │   └── Cargo.toml
│   ├── basic_example_json_batch/       # JSON batch ingestion example
│   │   ├── src/main.rs                 # Example usage code
│   │   └── Cargo.toml
│   ├── basic_example_proto/            # Protocol Buffers single-record example
│   │   ├── src/main.rs                 # Example usage code
│   │   ├── output/                     # Generated schema files
│   │   │   ├── orders.proto
│   │   │   ├── orders.rs
│   │   │   └── orders.descriptor
│   │   └── Cargo.toml
│   └── basic_example_proto_batch/      # Protocol Buffers batch ingestion example
│       ├── src/main.rs                 # Example usage code
│       ├── output/                     # Generated schema files
│       │   ├── orders.proto
│       │   ├── orders.rs
│       │   └── orders.descriptor
│       └── Cargo.toml
│
├── tests/                              # Integration tests crate
│   ├── src/
│   │   ├── mock_grpc.rs                # Mock Zerobus gRPC server
│   │   └── rust_tests.rs               # Test suite
│   ├── build.rs
│   └── Cargo.toml
│
├── Cargo.toml                          # Workspace configuration
└── README.md                           # This file

Key Components

• sdk/ - The main library crate containing all SDK functionality
• tools/ - CLI tool for generating Protocol Buffer schemas from Unity Catalog tables
• examples/ - Complete working examples demonstrating SDK usage
• Workspace - Root Cargo.toml defines a Cargo workspace for unified builds

How It Works

Architecture Overview

+-----------------+
|    Your App     |
+-----------------+
        | 1. create_stream()
        v
+-----------------+
|   ZerobusSdk    |
| - Manages TLS   |
| - Creates       |
|   channels      |
+-----------------+
        | 2. Opens bidirectional gRPC stream
        v
+--------------------------------------+
|            ZerobusStream             |
| +----------------------------------+ |
| |           Supervisor             | | Manages lifecycle, recovery
| +----------------------------------+ |
|                  |                   |
|      +-----------+-----------+       |
|      v                       v       |
| +----------+          +----------+   | 
| |  Sender  |          | Receiver |   | Parallel tasks
| |  Task    |          |  Task    |   |
| +----------+          +----------+   |
|      ^                       |       |
|      |                       v       |
| +----------------------------------+ |
| |          Landing Zone            | | Inflight buffer
| +----------------------------------+ |
+--------------------------------------+
            | 3. gRPC stream
            v
+-----------------------+
|      Databricks       |
|    Zerobus Service    |
+-----------------------+

Data Flow

1. Ingestion - Your app calls stream.ingest_record(data) or stream.ingest_records(batch)
2. Buffering - Records are placed in the landing zone with logical offsets
3. Sending - Sender task sends records over gRPC with physical offsets
4. Acknowledgment - Receiver task gets server ack and resolves the future
5. Recovery - If connection fails, supervisor reconnects and resends unacked records

Authentication Flow

The SDK uses OAuth 2.0 client credentials flow:

1. SDK constructs authorization request with Unity Catalog privileges
2. Sends request to {uc_endpoint}/oidc/v1/token with client credentials
3. Token includes scoped permissions for the specific table
4. Token is attached to gRPC metadata as Bearer token
5. Fresh tokens are fetched automatically on each connection

Custom Authentication

For advanced use cases, you can implement the HeadersProvider trait to supply your own authentication headers. This is useful for integrating with a different OAuth provider, using a centralized token caching service, or implementing alternative authentication mechanisms.

Note: The headers you provide must still conform to the authentication protocol expected by the Zerobus service. The default implementation, OAuthHeadersProvider, serves as the reference for the required headers (authorization and x-databricks-zerobus-table-name). This feature provides flexibility in how you source your credentials, not in changing the authentication protocol itself.

Example:

use databricks_zerobus_ingest_sdk::*;
use std::collections::HashMap;
use std::sync::Arc;
use async_trait::async_trait;

struct MyCustomAuthProvider;

#[async_trait]
impl HeadersProvider for MyCustomAuthProvider {
    async fn get_headers(&self) -> ZerobusResult<HashMap<&'static str, String>> {
        let mut headers = HashMap::new();
        // Custom logic to fetch and cache a token would go here.
        headers.insert("authorization", "Bearer <your-token>".to_string());
        headers.insert("x-databricks-zerobus-table-name", "<your-table-name>".to_string());
        Ok(headers)
    }
}

async fn example(sdk: ZerobusSdk, table_properties: TableProperties) -> ZerobusResult<()> {
    let custom_provider = Arc::new(MyCustomAuthProvider {});
    let stream = sdk.create_stream_with_headers_provider(
        table_properties,
        custom_provider,
        None,
    ).await?;
    Ok(())
}

Usage Guide

The SDK supports two approaches for data serialization:

1. JSON - Simpler approach that uses JSON strings. No schema generation required, making it ideal for quick prototyping. See examples/README.md for a complete example.
2. Protocol Buffers - Type-safe approach with schema validation at compile time. Recommended for production use cases. This guide focuses on the Protocol Buffers approach.

For JSON-based ingestion, you can skip the schema generation step and directly pass JSON strings to ingest_record().

1. Generate Protocol Buffer Schema (Protocol Buffers approach only)

Important Note: The schema generation tool and examples are only available in the GitHub repository. The crate published on crates.io contains only the core Zerobus ingestion SDK logic. To generate protobuf schemas or see working examples, clone the repository:

git clone https://github.com/databricks/zerobus-sdk-rs.git
cd zerobus-sdk-rs

Use the included tool to generate schema files from your Unity Catalog table:

cd tools/generate_files

# For AWS
cargo run -- \
  --uc-endpoint "https://<your-workspace>.cloud.databricks.com" \
  --client-id "your-client-id" \
  --client-secret "your-client-secret" \
  --table "catalog.schema.table" \
  --output-dir "../../output"

# For Azure
cargo run -- \
  --uc-endpoint "https://<your-workspace>.azuredatabricks.net" \
  --client-id "your-client-id" \
  --client-secret "your-client-secret" \
  --table "catalog.schema.table" \
  --output-dir "../../output"

This generates three files:

• {table}.proto - Protocol Buffer schema definition
• {table}.rs - Rust structs with serialization code
• {table}.descriptor - Binary descriptor for runtime validation

See tools/generate_files/README.md for supported data types and limitations.

See examples/README.md for more information on how to get OAuth credentials.

2. Initialize the SDK

Create an SDK instance with your Databricks workspace endpoints:

// For AWS
let sdk = ZerobusSdk::new(
    "https://<your-shard-id>.zerobus.<region>.cloud.databricks.com".to_string(),  // Zerobus endpoint
    "https://<your-workspace>.cloud.databricks.com".to_string(),     // Unity Catalog endpoint
)?;

// For Azure
let sdk = ZerobusSdk::new(
    "https://<your-shard-id>.zerobus.<region>.azuredatabricks.net".to_string(),  // Zerobus endpoint
    "https://<your-workspace>.azuredatabricks.net".to_string(),     // Unity Catalog endpoint
)?;

Note: The workspace ID is automatically extracted from the Zerobus endpoint when ZerobusSdk::new() is called.

3. Configure Authentication

The SDK handles authentication automatically. You just need to provide:

• Client ID - Your OAuth client ID
• Client Secret - Your OAuth client secret
• Unity Catalog Endpoint - Passed to SDK constructor
• Table Name - Included in table properties

let client_id = "your-client-id".to_string();
let client_secret = "your-client-secret".to_string();

See examples/README.md for more information on how to get these credentials.

4. Create a Stream

Configure table properties and stream options:

use std::fs;
use prost::Message;
use prost_types::{FileDescriptorSet, DescriptorProto};

// Load descriptor from generated files
fn load_descriptor(path: &str, file: &str, msg: &str) -> DescriptorProto {
    let bytes = fs::read(path).expect("Failed to read descriptor");
    let file_set = FileDescriptorSet::decode(bytes.as_ref()).unwrap();

    let file_desc = file_set.file.into_iter()
        .find(|f| f.name.as_deref() == Some(file))
        .unwrap();

    file_desc.message_type.into_iter()
        .find(|m| m.name.as_deref() == Some(msg))
        .unwrap()
}

let descriptor_proto = load_descriptor(
    "output/orders.descriptor",
    "orders.proto",
    "table_Orders",
);

let table_properties = TableProperties {
    table_name: "catalog.schema.orders".to_string(),
    descriptor_proto,
};

let options = StreamConfigurationOptions {
    max_inflight_requests: 10000,
    recovery: true,
    recovery_timeout_ms: 15000,
    recovery_backoff_ms: 2000,
    recovery_retries: 4,
    ..Default::default()
};

let mut stream = sdk.create_stream(
    table_properties,
    client_id,
    client_secret,
    Some(options),
).await?;

5. Ingest Data

The SDK provides two ingestion methods:

Single Record Ingestion

Ingest records one at a time by encoding them with Protocol Buffers:

use prost::Message;

let record = YourMessage {
    field1: Some("value".to_string()),
    field2: Some(42),
};

let ack_future = stream.ingest_record(record.encode_to_vec()).await?;

Batch Ingestion

For higher throughput and all-or-nothing semantics, use ingest_records() to ingest multiple records at once:

use prost::Message;

let records: Vec<Vec<u8>> = vec![
    YourMessage { id: Some(1), /* ... */ }.encode_to_vec(),
    YourMessage { id: Some(2), /* ... */ }.encode_to_vec(),
    YourMessage { id: Some(3), /* ... */ }.encode_to_vec(),
];

let ack_future = stream.ingest_records(records).await?;
// Returns Some(offset) for non-empty batches, None for empty batches
let offset = ack_future.await?;

Batch API Semantics:

• All-or-nothing: The entire batch succeeds or fails as a unit. If any record in the batch fails, the entire batch is rejected.
• Atomic acknowledgment: You receive a single acknowledgment for the entire batch, not individual records.
• Better throughput: Reduces network overhead by sending multiple records in a single request.
• Empty batches: Ingesting an empty batch is a no-op. The future resolves to None.
• Preserved on failure: Batches are preserved as units when retrieving via get_unacked_batches() or when reingested via recreate_stream(). Note that get_unacked_records() flattens batches into individual records.

High throughput patterns:

Both ingest_record() and ingest_records() return two futures:

1. The outer future (awaited immediately) confirms the record/batch is queued for sending
2. The inner future (the acknowledgment) resolves when the server confirms receipt

You don't need to wait for each acknowledgment before ingesting more records or batches. Instead, collect the ack futures and flush periodically:

let mut ack_futures_cnt = 0;

// Example with single-record ingestion
for i in 0..100_000 {
    let record = YourMessage {
        id: Some(i),
        timestamp: Some(chrono::Utc::now().timestamp()),
        data: Some(format!("record-{}", i)),
    };

    // This await only waits for the record to be queued, not for server ack
    let _ack = stream.ingest_record(record.encode_to_vec()).await?;
    ack_futures_cnt += 1;

    // Periodically flush and wait for acks to avoid unbounded memory growth
    if ack_futures_cnt >= 10_000 {
        stream.flush().await?;
        ack_futures_cnt = 0;
    }
}

// Flush and wait for remaining acknowledgments
stream.flush().await?;

// Same pattern works for batch ingestion
let batches = vec![/* batch1 */, /* batch2 */, /* batch3 */];
for batch in batches {
    let _ack = stream.ingest_records(batch).await?;
    ack_futures_cnt += 1;
    // ...
}

Parallelizing with multiple streams:

Since each stream uses a single gRPC connection, opening multiple threads on the same stream doesn't improve throughput. For true parallelization, open multiple streams (e.g., partition your data):

use tokio::task::JoinSet;

let mut tasks = JoinSet::new();

// Partition data across multiple streams for parallel ingestion
for partition in 0..4 {
    let sdk_clone = sdk.clone();
    let table_properties = table_properties.clone();
    let client_id = client_id.clone();
    let client_secret = client_secret.clone();

    tasks.spawn(async move {
        let mut stream = sdk_clone.create_stream(
            table_properties,
            client_id,
            client_secret,
            None,
        ).await?;

        // Ingest partition data (using single-record or batch ingestion)
        for i in (partition * 25_000)..((partition + 1) * 25_000) {
            let record = YourMessage { id: Some(i), /* ... */ };
            let _ack = stream.ingest_record(record.encode_to_vec()).await?;
        }

        //Close implicitly waits for all acknowledgments from the server.
        stream.close().await?; 
        Ok::<_, ZerobusError>(())
    });
}

// Wait for all streams to complete
while let Some(result) = tasks.join_next().await {
    result??;
}

6. Handle Acknowledgments

Both ingest_record() and ingest_records() return a future for acknowledgment:

• ingest_record() resolves to OffsetId (the committed offset)
• ingest_records() resolves to Option<OffsetId> (None if the batch is empty)

// Fire-and-forget (not recommended for production)
let ack = stream.ingest_record(data).await?;
tokio::spawn(ack);

// Wait for acknowledgment immediately
let ack = stream.ingest_record(data).await?;
let offset = ack.await?;
println!("Record committed at offset: {}", offset);

// For batches, ack returns Option<OffsetId>
// (None if the batch is empty)
let batch = vec![data1, data2, data3];
let ack = stream.ingest_records(batch).await?;
if let Some(offset) = ack.await? {
    println!("Last acknowledged offset: {}", offset);
} else {
    println!("Empty batch, no records ingested");
}

// High-throughput: collect acks and check them later
let mut acks = Vec::new();
for i in 0..1000 {
    let ack = stream.ingest_record(record).await?;
    acks.push(ack);
}
for ack in acks {
    ack.await?;
}

// Or use flush() to wait for all pending acknowledgments at once
stream.flush().await?;

7. Close the Stream

Always close streams to ensure data is flushed:

// Close gracefully (flushes automatically)
stream.close().await?;

If the stream fails, retrieve unacknowledged records:

match stream.close().await {
    Err(_) => {
        // Option 1: Get individual records (flattened)
        let unacked = stream.get_unacked_records().await?;
        let total_records = unacked.count();
        println!("Failed to ack {} records", total_records);
        
        // Option 2: Get records grouped by batch (preserves batch structure)
        let unacked_batches = stream.get_unacked_batches().await?;
        let total_records: usize = unacked_batches.iter().map(|batch| batch.get_record_count()).sum();
        println!("Failed to ack {} records in {} batches", total_records, unacked_batches.len());
        
        // Retry with a new stream
    }
    Ok(_) => println!("Stream closed successfully"),
}

Configuration Options

StreamConfigurationOptions

Field	Type	Default	Description
max_inflight_requests	usize	1,000,000	Maximum unacknowledged requests in flight
recovery	bool	true	Enable automatic stream recovery on failure
recovery_timeout_ms	u64	15,000	Timeout for recovery operations (ms)
recovery_backoff_ms	u64	2,000	Delay between recovery retry attempts (ms)
recovery_retries	u32	4	Maximum number of recovery attempts
flush_timeout_ms	u64	300,000	Timeout for flush operations (ms)
server_lack_of_ack_timeout_ms	u64	60,000	Timeout waiting for server acks (ms)
record_type	RecordType	RecordType::Proto	Record serialization format (Proto or Json)

Example:

let options = StreamConfigurationOptions {
    max_inflight_requests: 50000,
    recovery: true,
    recovery_timeout_ms: 20000,
    recovery_retries: 5,
    flush_timeout_ms: 600000,
    ..Default::default()
};

Error Handling

The SDK categorizes errors as retryable or non-retryable:

Retryable Errors

Auto-recovered if recovery is enabled:

• Network failures
• Connection timeouts
• Temporary server errors
• Stream closed by server

Non-Retryable Errors

Require manual intervention:

• InvalidUCTokenError - Invalid OAuth credentials
• InvalidTableName - Table doesn't exist or invalid format
• InvalidArgument - Invalid parameters or schema mismatch
• Code::Unauthenticated - Authentication failure
• Code::PermissionDenied - Insufficient table permissions
• ChannelCreationError - Failed to establish TLS connection

Check if an error is retryable:

match stream.ingest_record(payload).await {
    Ok(ack) => {
        let offset = ack.await?;
    }
    Err(e) if e.is_retryable() => {
        eprintln!("Retryable error, SDK will auto-recover: {}", e);
    }
    Err(e) => {
        eprintln!("Fatal error, manual intervention needed: {}", e);
        return Err(e.into());
    }
}

Examples

Complete Working Examples

The examples/ directory contains four working examples covering different serialization formats and ingestion patterns:

Example	Serialization	Ingestion	Description
basic_example_json/	JSON	Single-record	Simple JSON strings, no schema required
basic_example_json_batch/	JSON	Batch	Multiple JSON records with all-or-nothing semantics, no schema required
basic_example_proto/	Protocol Buffers	Single-record	Type-safe with compile-time validation
basic_example_proto_batch/	Protocol Buffers	Batch	High-throughput batch ingestion with Proto

Check examples/README.md for setup instructions and detailed comparisons.

Stream Recovery

let sdk = ZerobusSdk::new(endpoint, uc_endpoint);

let mut stream = sdk.create_stream(
    table_properties.clone(),
    client_id.clone(),
    client_secret.clone(),
    Some(options),
).await?;

// Ingest data...
match stream.close().await {
    Err(_) => {
        // Stream failed, recreate with unacked records
        stream = sdk.recreate_stream(stream).await?;
    }
    Ok(_) => println!("Closed successfully"),
}

Tests

Integration tests live in the tests/ crate and run against a lightweight mock Zerobus gRPC server.

• Mock server: tests/src/mock_grpc.rs
• Test suite: tests/src/rust_tests.rs

Run tests with logs:

cargo test -p tests -- --nocapture

Best Practices

1. Reuse SDK Instances - Create one ZerobusSdk per application and reuse for multiple streams
2. Always Close Streams - Use stream.close().await? to ensure all data is flushed
3. Choose the Right Ingestion Method:
   • Use ingest_records() for high throughput when you have multiple records ready
   • Use ingest_record() when processing records individually or need per-record acknowledgment
4. Tune Inflight Limits - Adjust max_inflight_requests based on memory and throughput needs
5. Enable Recovery - Always set recovery: true in production environments
6. Handle Ack Futures - Use tokio::spawn for fire-and-forget or batch-wait for verification
7. Monitor Errors - Log and alert on non-retryable errors
8. Validate Schemas - Use the schema generation tool to ensure type safety (for Protocol Buffers)
9. Secure Credentials - Never hardcode secrets; use environment variables or secret managers
10. Test Recovery - Simulate failures to verify your error handling logic

API Reference

ZerobusSdk

Main entry point for the SDK.

Constructor:

pub fn new(zerobus_endpoint: String, unity_catalog_url: String) -> ZerobusResult<Self>

Methods:

pub async fn create_stream(
    &self,
    table_properties: TableProperties,
    client_id: String,
    client_secret: String,
    options: Option<StreamConfigurationOptions>,
) -> ZerobusResult<ZerobusStream>

pub async fn recreate_stream(
    &self,
    stream: ZerobusStream
) -> ZerobusResult<ZerobusStream>

Recreates a failed stream, preserving and re-ingesting unacknowledged records.

pub async fn create_stream_with_headers_provider(
    &self,
    table_properties: TableProperties,
    headers_provider: Arc<dyn HeadersProvider>,
    options: Option<StreamConfigurationOptions>,
) -> ZerobusResult<ZerobusStream>

Creates a stream with a custom headers provider for advanced authentication.

ZerobusStream

Represents an active ingestion stream.

Methods:

pub async fn ingest_record(
    &self,
    payload: Vec<u8>
) -> ZerobusResult<impl Future<Output = ZerobusResult<OffsetId>>>>

Ingests a single encoded record (Protocol Buffers or JSON). Returns a future that resolves to the offset ID.

pub async fn ingest_records(
    &self,
    payloads: Vec<Vec<u8>>
) -> ZerobusResult<impl Future<Output = ZerobusResult<Option<OffsetId>>>>

Ingests multiple encoded records as a batch with all-or-nothing semantics. The entire batch either succeeds or fails as a unit. Returns a future that resolves to Some(offset_id) for non-empty batches, or None if the batch is empty.

pub async fn flush(&self) -> ZerobusResult<()>

Flushes all pending records and waits for acknowledgment.

pub async fn close(&mut self) -> ZerobusResult<()>

Flushes and closes the stream gracefully.

pub async fn get_unacked_records(&self) -> ZerobusResult<impl Iterator<Item = EncodedRecord>>

Returns an iterator over all unacknowledged records as individual EncodedRecord items. This flattens batches into individual records. Only call after stream failure.

pub async fn get_unacked_batches(&self) -> ZerobusResult<Vec<EncodedBatch>>

Returns unacknowledged records grouped by batch, preserving the original batch structure. Records ingested together remain grouped:

• Each ingest_record() call creates a batch containing one record
• Each ingest_records() call creates a batch containing multiple records

Only call after stream failure.

TableProperties

Configuration for the target table.

Fields:

pub struct TableProperties {
    pub table_name: String,
    pub descriptor_proto: Option<prost_types::DescriptorProto>,
}

• table_name - Full table name (e.g., "catalog.schema.table")
• descriptor_proto - Optional Protocol buffer descriptor loaded from generated files (required for Proto record type, None for JSON)

StreamConfigurationOptions

Stream behavior configuration.

Fields:

pub struct StreamConfigurationOptions {
    pub max_inflight_requests: usize,
    pub recovery: bool,
    pub recovery_timeout_ms: u64,
    pub recovery_backoff_ms: u64,
    pub recovery_retries: u32,
    pub flush_timeout_ms: u64,
    pub server_lack_of_ack_timeout_ms: u64,
    pub record_type: RecordType,
}

See Configuration Options for details.

ZerobusError

Error type for all SDK operations.

Methods:

pub fn is_retryable(&self) -> bool

Returns true if the error can be automatically recovered by the SDK.

Building from Source

For contributors or those who want to build and test the SDK:

git clone https://github.com/YOUR_USERNAME/zerobus_rust_sdk.git
cd zerobus_rust_sdk
cargo build --workspace

Build specific components:

# Build only SDK
cargo build -p databricks-zerobus-ingest-sdk

# Build only schema tool
cargo build -p generate_files

# Build and run JSON example
cargo run -p basic_example_json

# Build and run Protocol Buffers example
cargo run -p basic_example_proto

Community and Contributing

This is an open source project. We welcome contributions, feedback, and bug reports.

• Contributing Guide: Learn how to contribute, including our development process and coding style.
• Changelog: See the history of changes in the SDK.
• Security Policy: Read about our security process and how to report vulnerabilities.
• Developer Certificate of Origin (DCO): Understand the agreement for contributions.
• Open Source Attributions: See a list of the open source libraries we use.

License

This SDK is licensed under the Databricks License. See the LICENSE file for the full license text. The license is also available online at https://www.databricks.com/legal/db-license.

Requirements

• Rust 1.70 or higher (2021 edition)

• Databricks workspace with Zerobus access enabled

• OAuth 2.0 client credentials (client ID and secret)

• Unity Catalog endpoint access

• TLS - Uses native OS certificate store

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For issues, questions, or contributions, please visit the GitHub repository.