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python import kudu

Of course. Here's a comprehensive guide on how to import and use the Kudu Python client, from installation to basic usage.

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Understanding Kudu and its Python Client

First, it's important to clarify what "Kudu" refers to in this context. There are two prominent projects named Kudu:

  1. Apache Kudu: A columnar storage manager developed for the Hadoop platform. It is designed for fast analytics on fast data, combining the best traits of relational databases and data warehouses. This is the most common meaning when discussing "Kudu" in a data engineering context.
  2. Google Kudu (deprecated): A tool for deploying and managing applications on Google Cloud Platform (GCP). It was officially deprecated in 2025 and replaced by Google Cloud Build.

When you see import kudu in Python, it almost always refers to the Python client for Apache Kudu.


Prerequisites: The C++ Client Library

The Python Kudu client is a wrapper around a C++ core library. Therefore, you cannot just pip install it. You must first install the underlying C++ Kudu client libraries on your system.

Why is this necessary? The Python package (pykudu) contains the Python-specific code, but it links to the compiled C++ libraries (libkudu) to do the heavy lifting of talking to Kudu clusters.

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Installation Steps for the C++ Library

The method depends on your operating system.

For Debian/Ubuntu: Use apt-get. This is the recommended method if you're using a standard Ubuntu environment.

# Add the Kudu repository (if not already added)
# This example uses the Cloudera repository, which is common.
# You might need to adjust this based on your source.
echo "deb http://archive.cloudera.com/kudu/ubuntu/precise/amd64/kudu-1.7.0 trusty contrib" | sudo tee /etc/apt/sources.list.d/kudu.list
# Add the repository key
wget -qO - http://archive.cloudera.com/kudu/ubuntu/precise/amd64/kudu-1.7.0/Release.key | sudo apt-key add -
# Update package lists and install
sudo apt-get update
sudo apt-get install libkudu-client-dev

For RHEL/CentOS/Fedora: Use yum or dnf.

# For RHEL/CentOS 7
sudo yum install -y kudu-client-devel
# For Fedora
sudo dnf install -y kudu-client-devel

For macOS (using Homebrew): Homebrew has a formula for Kudu.

brew install kudu

For Building from Source: If a pre-built package isn't available for your system, you'll need to build Kudu from source. This is a more complex process and is documented in the official Apache Kudu documentation.


Installing the Python Client (pykudu)

Once the C++ library is installed, you can install the Python wrapper using pip.

pip install pykudu

If you are in a virtual environment, make sure it's activated before running this command.


How to Import and Use kudu in Python

Now that the installation is complete, you can start using the library in your Python scripts.

Basic Workflow:

  1. Import the necessary modules.
  2. Create a Kudu Client to connect to your Kudu cluster.
  3. Open a Table to perform operations on it.
  4. Create a Kudu Session to group operations (write operations are asynchronous by default).
  5. Perform Operations: Insert, Update, Delete, or Scan data.
  6. Flush the session to send the buffered operations to the Kudu master.
  7. Close the table and client when done.

Example Code

Here is a complete, commented example demonstrating the core functionality.

# 1. Import the necessary modules
from kudu.client import KuduClient
from kudu.schema import ColumnSchema, Schema
from kudu.types import Int32, StringType, Float64, Boolean
import time
# --- Configuration ---
# Replace with the addresses of your Kudu master servers.
# For a single-node setup, it might be just 'ip-address:7051'.
# For a multi-master setup, provide a comma-separated list.
KUDU_MASTERS = 'kudu-master-node1:7051,kudu-master-node2:7051,kudu-master-node3:7051'
TABLE_NAME = 'python_example_users'
def main():
    # 2. Create a Kudu Client
    # This client object manages the connection to the Kudu cluster.
    client = KuduClient(KUDU_MASTERS)
    # --- Table Creation ---
    # Define the schema for our table
    columns = [
        ColumnSchema('id', type_=Int32, nullable=False, primary_key=True),
        ColumnSchema('username', type_=StringType, nullable=False),
        ColumnSchema('email', type_=StringType, nullable=True),
        ColumnSchema('age', type_=Int32, nullable=True),
        ColumnSchema('is_active', type_=Boolean, nullable=True, default_value=True),
        ColumnSchema('balance', type_=Float64, nullable=True, default_value=0.0)
    ]
    schema = Schema(columns)
    # Create the table if it doesn't exist
    # We specify a partitioning scheme for scalability.
    # range_partitioning is a common choice.
    try:
        print(f"Creating table '{TABLE_NAME}'...")
        client.create_table(TABLE_NAME, schema,
                            partitioning_columns=['id'],
                            partitions=[
                                {'range': {'lower_bound': 0, 'upper_bound': 1000, 'num_buckets': 4}},
                                {'range': {'lower_bound': 1000, 'upper_bound': 2000, 'num_buckets': 4}}
                            ])
        print("Table created successfully.")
    except Exception as e:
        # It's okay if the table already exists
        if "already exists" in str(e):
            print(f"Table '{TABLE_NAME}' already exists.")
        else:
            raise e
    # 3. Open the table for operations
    table = client.table(TABLE_NAME)
    # 4. Create a Kudu Session
    # A session groups operations. By default, operations are flushed
    # automatically when the buffer is full or after a timeout.
    session = client.new_session()
    # For synchronous operations (simpler but less performant):
    # session = client.new_session(flush_mode='MANUAL')
    # session.flush() # You would call this manually after each operation.
    # --- Data Insertion ---
    print("\n--- Inserting rows ---")
    users_to_insert = [
        {'id': 1, 'username': 'alice', 'email': 'alice@example.com', 'age': 30},
        {'id': 2, 'username': 'bob', 'email': 'bob@example.com', 'age': 25},
        {'id': 3, 'username': 'charlie', 'email': None, 'age': 35, 'is_active': False},
    ]
    for user_data in users_to_insert:
        # Create an Insert operation object
        insert = table.new_insert()
        # Set the values for each column
        for col_name, value in user_data.items():
            insert.set(col_name, value)
        # Apply the operation to the session
        session.apply(insert)
        print(f"Applied insert for user: {user_data['username']}")
    # 5. Flush the session to send the operations to Kudu
    # This is crucial for write operations.
    session.flush()
    print("Session flushed. Inserts should be complete.")
    # --- Data Scanning (Reading) ---
    print("\n--- Scanning all rows ---")
    # Create a scanner to read data from the table
    scanner = table.scanner()
    # You can add filters, column projections, etc.
    # scanner.select(['id', 'username', 'age']).where('age > 28')
    for row in scanner:
        # Each row is a KuduRow object. You can access values by column name.
        print(f"ID: {row['id']}, Username: {row['username']}, Age: {row['age']}, Email: {row['email']}")
    # --- Data Updating ---
    print("\n--- Updating a row (Bob's age) ---")
    # Kudu updates are UPSERTs (Update or Insert). If the row exists, it updates.
    update = table.new_upsert()
    update.set('id', 2)  # The primary key is required for the lookup
    update.set('age', 26) # The new value
    session.apply(update)
    session.flush()
    print("Updated Bob's age to 26.")
    # Verify the update
    print("\n--- Verifying the update ---")
    scanner = table.scanner().select(['id', 'username', 'age']).where('id = 2')
    for row in scanner:
        print(f"ID: {row['id']}, Username: {row['username']}, New Age: {row['age']}")
    # --- Data Deleting ---
    print("\n--- Deleting a row (Charlie) ---")
    delete = table.new_delete()
    delete.set('id', 3) # The primary key is required for the lookup
    session.apply(delete)
    session.flush()
    print("Deleted user with ID 3.")
    # Verify the deletion
    print("\n--- Verifying the deletion ---")
    scanner = table.scanner().select(['id', 'username'])
    print("Remaining users in the table:")
    for row in scanner:
        print(f"ID: {row['id']}, Username: {row['username']}")
    # --- Cleanup ---
    # 7. Close the table and client
    # This releases resources on the client side.
    table.close()
    client.close()
    print("\nKudu client closed.")
if __name__ == '__main__':
    main()

Troubleshooting Common Issues

  • ImportError: libkudu.so.1: cannot open shared object file

    • Cause: The most common error. It means the Python interpreter cannot find the C++ Kudu shared library (libkudu).
    • Solution: You did not successfully install the libkudu-client-dev (or equivalent) package in Step 2. Revisit the installation instructions for your OS. You may also need to set the LD_LIBRARY_PATH environment variable to point to the directory where libkudu.so is located (e.g., /usr/local/lib).
  • No module named 'kudu'

    • Cause: The Python pykudu package itself is not installed.
    • Solution: Run pip install pykudu again, ensuring you are in the correct Python environment.
  • RPC failed: ... or connection errors

    • Cause: The KUDU_MASTERS address in your code is incorrect, the Kudu cluster is not running, or a firewall is blocking the connection (default port is 7051).
    • Solution: Double-check the IP addresses and port numbers. Use tools like telnet <master-ip> 7051 or nc -zv <master-ip> 7051 to test network connectivity.
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