This repository is based on https://github.com/duckdb/extension-template, check it out if you want to build and ship your own DuckDB extension.
This extension, Snowflake, allow you to ... <extension_goal>.
DuckDB extensions uses VCPKG for dependency management. Enabling VCPKG is very simple: follow the installation instructions or just run the following:
git clone https://github.com/Microsoft/vcpkg.git
./vcpkg/bootstrap-vcpkg.sh
export VCPKG_TOOLCHAIN_PATH=`pwd`/vcpkg/scripts/buildsystems/vcpkg.cmake
Note: VCPKG is only required for extensions that want to rely on it for dependency management. If you want to develop an extension without dependencies, or want to do your own dependency management, just skip this step. Note that the example extension uses VCPKG to build with a dependency for instructive purposes, so when skipping this step the build may not work without removing the dependency.
Now to build the extension, run:
make
The main binaries that will be built are:
./build/release/duckdb
./build/release/test/unittest
./build/release/extension/snowflake/snowflake.duckdb_extension
duckdb
is the binary for the duckdb shell with the extension code automatically loaded.unittest
is the test runner of duckdb. Again, the extension is already linked into the binary.snowflake.duckdb_extension
is the loadable binary as it would be distributed.
To run the extension code, simply start the shell with ./build/release/duckdb
.
Now we can use the features from the extension directly in DuckDB. The template contains a single scalar function snowflake()
that takes a string arguments and returns a string:
D select snowflake('Jane') as result;
┌───────────────┐
│ result │
│ varchar │
├───────────────┤
│ Snowflake Jane 🐥 │
└───────────────┘
Different tests can be created for DuckDB extensions. The primary way of testing DuckDB extensions should be the SQL tests in ./test/sql
. These SQL tests can be run using:
make test
To install your extension binaries from S3, you will need to do two things. Firstly, DuckDB should be launched with the
allow_unsigned_extensions
option set to true. How to set this will depend on the client you're using. Some examples:
CLI:
duckdb -unsigned
Python:
con = duckdb.connect(':memory:', config={'allow_unsigned_extensions' : 'true'})
NodeJS:
db = new duckdb.Database(':memory:', {"allow_unsigned_extensions": "true"});
Secondly, you will need to set the repository endpoint in DuckDB to the HTTP url of your bucket + version of the extension you want to install. To do this run the following SQL query in DuckDB:
SET custom_extension_repository='bucket.s3.eu-west-1.amazonaws.com/<your_extension_name>/latest';
Note that the /latest
path will allow you to install the latest extension version available for your current version of
DuckDB. To specify a specific version, you can pass the version instead.
After running these steps, you can install and load your extension using the regular INSTALL/LOAD commands in DuckDB:
INSTALL snowflake
LOAD snowflake