This repo demonstrates using Knex.js with Neon's serverless driver on Vercel Edge Functions.
We implement a simple app that generates a JSON listing of the user's nearest 10 UNESCO World Heritage sites via IP geolocation (data copyright © 1992 – 2022 UNESCO/World Heritage Centre).
The Vercel Edge Function API endpoint source is found in ./api-src.
Knex.js tries to import some Node.js modules that aren't available on Edge Functions. We provide shims for these modules in ./shims, and these are listed as file: packages in package.json. The assert, events and util.promisify packages are also installed to support Knex.js.
To make the shims work with Edge Functions requires a build step. We use esbuild to bundle the source files in ./api-src with all dependencies, depositing the output files in ./api. The build command is found in package.json > "scripts" > "build".
Note that the line export const config = { runtime: 'edge' }, which is required to create an Edge function, is not present in the source files. Because it must take this specific form, it is instead appended at the end of the build process. It can be edited (e.g. to add a regions key) in the --footer:js= argument of the esbuild build command.
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Ensure the
psqlclient is installed. -
Create a Neon database and make a note of the connection string from the Neon console.
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Clone this repo, then:
# get dependencies
npm install
npm install -g vercel@latest
# set up Vercel
npx vercel login
npx vercel link
# create DATABASE_URL environment variable, remote and local
npx vercel env add DATABASE_URL # paste in the connection string: postgres://...
npx vercel env pull .env.local # now bring it down into ./.env.local for local use
# create the schema and copy data to DB
(source .env.local \
&& curl -s https://gist.githubusercontent.com/jawj/a8d53ff339707c65128af83b4783f4fe/raw/45dbcc819b00ecb72f80b0cf91e01b3d055662b5/whc-sites-2021.psql \
| psql $DATABASE_URL)
# test ...
npx vercel dev
# ... and deploy
npx vercel deployPlease visit Neon Community or Support.