postgres

Postgres example

In this example, we showcase how to make async (non blocking) connections to Postgres databases from WasmEdge Rust apps. It utilizes the tokio-postgres_wasi crate, which is derived from tokio-postgres.

Linux CLI usage

Prerequisites:

• Install the Rust compiler and Cargo tools
• Install the WasmEdge Runtime
• Install and start the PostgreSQL server
  • Create a username wasmedge with password 'rocks`
  • Create a database testdb for user wasmedge

The following commands build and run the example.

cargo build --target wasm32-wasi --release
wasmedge --env "DATABASE_URL=postgres://wasmedge:rocks@localhost/testdb" target/wasm32-wasi/release/crud.wasm

Docker usage

The following command builds and starts two containers. All you need is Docker Desktop. There is no need to install Rust or Redis or even WasmEdge.

• One is a Wasm container for the PostgreSQL client app. The entire container image is only 0.9MB -- far smaller than any Linux container.
• The second is a Linux container for the PostgreSQL server.

docker compose up