Basic Wasm Module Evaluation Example

The main.go example demonstrates the loading and executing of OPA produced wasm policy binary.

Setup

The example directory includes some Rego source files. The first step is to compile them into Wasm modules. Run:

opa build -t wasm -e example/allow ./example-1.rego

This will generate a bundle.tar.gz in your current directory which has the Wasm module included. Extract the module with:

tar -zxvf bundle.tar.gz /policy.wasm
mv policy.wasm example-1.wasm

Repeat the process for the second example Wasm binary:

opa build -t wasm -e example/allow ./example-2.rego
tar -zxvf bundle.tar.gz /policy.wasm
mv policy.wasm example-2.wasm

The final result should be two Wasm modules:

example-1.wasm
example-2.wasm

Running the Example

After the Wasm binaries are available run the example with

go run main.go .

This should be run from the same directory as main.go, alternatively provide a path to the directory which contains the Wasm binaries.