Handle SIGINT signals

Without this commit, you have to provide the --init argument to Docker.
See moby/moby#2838 (comment)

This also adds a test that verifies that this works.

Cargo.toml

@@ -21,6 +21,7 @@ serde = { version = "1.0", features = ["derive"] } # For (de-)serialization supp
 serde_json = "1.0" # For (de-)serializing JSON
 slippy_map_tilenames = "0.2" # For calculating the coordinates of map tiles
 tree_magic = { version = "0.2", features = ["staticmime"] } # For determining MIME types based on content
+signal-hook = "0.1" # For correct signal handling if we have pid = 1
 
 [profile.release]
 lto = true

README.md

@@ -99,7 +99,16 @@ like `https://your.domain/my-images/8efbfe48-9a8a-41a8-8b2d-307b8cfffff4.jpg` to
 
 You can find the API documentation [here](API.md).
 
-## Testing the API
+## Tests
+
+Our integration tests are based on [bats](https://github.com/bats-core/bats-core).
+To run them use:
+
+```
+bats tests
+```
+
+## Interactively testing the API
 
 Compile the backend with the `testpages` feature to have easy access to rudimentary testpages at `/testpages/`.
 

src/main.rs

@@ -31,6 +31,13 @@ fn testpage_routes() -> Option<Vec<Route>> {
 fn main() {
     check_required_configuration();
 
+    unsafe {
+        signal_hook::register(signal_hook::SIGINT, || {
+            println!("Received SIGINT signal.");
+            std::process::exit(0);
+        }).expect("signal handler could not be set");
+    }
+
     let mut rocket = rocket::ignite()
         .attach(DatabaseConnection::fairing())
         .mount("/facilities", facilites_routes())

tests/framework.bash

@@ -0,0 +1,45 @@
+# Common functions used for our tests
+
+# use this instead of echo inside tests
+log() {
+  local BLUE='\033[0;34m'
+  local RESET='\033[0m'
+  echo -e "$BLUE"[test] "$*""$RESET"
+}
+
+container-running() {
+  [ "$(docker inspect -f '{{.State.Running}}' "$1")" = "true" ]
+}
+
+container-stop() {
+  # ignore if there is an error (which means that the container is already stopped)
+  docker stop "$1" 2>&1>/dev/null || true
+}
+
+containers-stop() {
+  [ -n "${TONARI:-}" ] && container-stop "$TONARI"
+  [ -n "${MONGO:-}" ] && container-stop "$MONGO"
+}
+
+containers-run() {
+  export TONARI_SOURCE_ID=${TONARI_SOURCE_ID:-00000000000000000000000000000000}
+  export TONARI_IMAGE_URL_PREFIX=${TONARI_IMAGE_URL_PREFIX:-https://tonari.app/api/images/}
+  export TONARI_IMAGE_PATH=${TONARI_IMAGE_PATH:-/images}
+  export TONARI_DATABASE_NAME=${TONARI_DATABASE_NAME:-tonari}
+  export ROCKET_DATABASES=${ROCKET_DATABASES:-'{sanitary_facilities={url="mongodb://localhost:27017/sanitary_facilities"}}'}
+  export ROCKET_PORT=${ROCKET_PORT:-8000}
+  ROCKET_SECRET_KEY_DEFAULT=$(openssl rand -base64 32)
+  export ROCKET_SECRET_KEY=${ROCKET_SECRET_KEY:-$ROCKET_SECRET_KEY_DEFAULT}
+  export MONGO=$(docker run -d -p 27017:27017 mongo --wiredTigerCacheSizeGB 1.5)
+  export TONARI=$(docker run -d -eTONARI_{SOURCE_ID,IMAGE_URL_PREFIX,IMAGE_PATH} -eROCKET_{DATABASES,PORT} --network=host tonari/backend)
+}
+
+# bats setup
+setup() {
+  containers-run
+}
+
+# bats teardown
+teardown() {
+  containers-stop
+}

tests/sigint-stops-docker-container.bats

@@ -0,0 +1,23 @@
+#!/usr/bin/env bats
+
+load framework
+
+# Test if a SIGINT signal stops the Docker container
+@test "SIGINT stops Docker container" {
+  # wait so that the container is stopped if there are any startup problems
+  sleep 1
+
+  if ! container-running $TONARI; then
+    log Tonari failed to start:
+    docker logs $TONARI
+    echo Tonari is running > /dev/null
+    return 1
+  fi
+
+  docker kill --signal=SIGINT $TONARI > /dev/null
+  sleep 4
+  if container-running $TONARI; then
+    log Tonari failed to be killed
+    false
+  fi
+}