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.

Note: A peer project is https://github.com/Maxxen/duckdb-postal, which currently does this a lot better than this repo. I probably develop off of that version if I start working on this again. But there are some problems with global state in libpostal that don't play well with DuckDB that probably need to get resolved first, and that looks like a lot of work, so I don't have any short-term plans to work more on this.

This project is a DuckDB extension that wraps the libpostal C library, allowing you to parse and normalize addresses from within DuckDB.

This extension provides a single scalar function: parse_address(string) -> array<struct<token:string, label:str>>

D select parse_address('123 Wallaby Way, Sydney, Austra') as result;
┌───────────────┐
│    result     │
│    varchar    │
├───────────────┤
│ Quack Jane 🐥 │
└───────────────┘

libpostal is not included in vcpkg, so I included it via git submodules. First step is to build and install libpostal with make libpostal-build. Then, continue with the rest of the following steps.

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/postal/postal.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.
• postal.duckdb_extension is the loadable binary as it would be distributed.

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 postal
LOAD postal