tests(compute-static): add basic unit tests

.github/workflows/main.yml

@@ -23,6 +23,13 @@ jobs:
       - name: Run clippy
         run: cargo clippy --all -- -Dwarnings
 
+      - name: Run compute-static tests
+        working-directory: terragrunt/modules/crates-io/compute-static
+        run: |
+          curl -LsSf https://get.nexte.st/latest/linux | tar zxf - -C ${CARGO_HOME:-~/.cargo}/bin
+          cargo install --locked viceroy --version 0.15.0
+          ./scripts/run_tests.sh
+
   terraform:
     name: Terraform configuration
     runs-on: ubuntu-24.04

terragrunt/modules/crates-io/compute-static/.cargo/config.toml

@@ -1,2 +1,5 @@
 [build]
-target = "wasm32-wasi"
+target = "wasm32-wasip1"
+
+[target.wasm32-wasip1]
+runner = "viceroy run -C fastly.toml -- "

terragrunt/modules/crates-io/compute-static/README.md

@@ -8,13 +8,43 @@ responses.
 
 ## Development
 
-Build the function:
+Install the Fastly CLI from [here](https://www.fastly.com/documentation/reference/tools/cli/#installing).
+
+Then, build the function:
 
 ```shell
 cd compute-static
 fastly compute build
 ```
 
+## Testing
+
+Testing requires [cargo-nextest](https://nexte.st/docs/installation/pre-built-binaries/), as specified in
+the [Fastly documentation](https://www.fastly.com/documentation/guides/compute/developer-guides/rust/). You can install
+it from source with binstall:
+
+```shell
+cargo install cargo-binstall
+cargo binstall cargo-nextest --secure
+```
+
+Then, install [Viceroy](https://github.com/fastly/Viceroy) to run the edge function locally:
+
+```shell
+cargo install --locked viceroy
+```
+
+Due to the fact Viceroy does not allow easily mocking HTTP requests being sent (
+see [issue](https://github.com/fastly/Viceroy/issues/442)), some tests use a small Python HTTP
+server to work.
+For this reason, a wrapper bash script is provided that runs `cargo nextest run` with the test server active in
+background. You can therefore run the tests with:
+:
+
+```shell
+./run_tests.sh
+```
+
 ## Deployment
 
 Terraform uses an [external data source] to build the function as part of its

terragrunt/modules/crates-io/compute-static/rust-toolchain.toml

@@ -1,3 +1,3 @@
 [toolchain]
-channel = "stable"
+channel = "1.90"
 targets = ["wasm32-wasip1"]

terragrunt/modules/crates-io/compute-static/scripts/run_tests.sh

@@ -0,0 +1,16 @@
+#!/bin/bash
+
+# Start the Python HTTP server in the background, which will act as primary host for requests sent from Rust tests
+python3 scripts/test_http_server.py &
+SERVER_PID=$!
+
+echo "HTTP server started with PID: $SERVER_PID"
+
+# Run the tests while the HTTP server is active in background
+cargo nextest run
+CARGO_EXIT_CODE=$?
+
+kill $SERVER_PID
+echo "HTTP server stopped"
+
+exit $CARGO_EXIT_CODE

terragrunt/modules/crates-io/compute-static/scripts/test_http_server.py

@@ -0,0 +1,16 @@
+from http.server import BaseHTTPRequestHandler, HTTPServer
+
+
+class MockHandler(BaseHTTPRequestHandler):
+    def do_GET(self):
+        if self.path == "/crates/libgit2-sys/libgit2-sys-0.12.25%2B1.3.0.crate":
+            self.send_response(200)
+            self.end_headers()
+            # The written data is used in Rust tests to verify whether the primary host (this) has actually been queried
+            self.wfile.write(b'test_data')
+        else:
+            self.send_response(404)
+            self.end_headers()
+
+
+HTTPServer(("127.0.0.1", 8080), MockHandler).serve_forever()