feat: add docker stack

Add the detection of a single Dockerfile, for the lint stage uses Hadolint to check the Dockerfile syntax and for the build stage tries to build the container

core/plugins/stack/docker/mod.ts

@@ -0,0 +1,20 @@
+import { Introspector } from "../deps.ts";
+
+/**
+ * Introspected information about a project with Docker
+ */
+export default interface DockerProject {
+  hasDockerImage: true;
+}
+
+export const introspector: Introspector<DockerProject> = {
+  detect: async (context) => {
+    return await context.files.includes("./Dockerfile");
+  },
+  introspect: async (context) => {
+    const logger = await context.getLogger("docker");
+    logger.info("Found docker image on root");
+
+    return { hasDockerImage: true };
+  },
+};

core/templates/github/docker/build.yml

@@ -0,0 +1,15 @@
+name: Docker Image CI
+
+on:
+  pull_request:
+    paths:
+      - "Dockerfile"
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+      - name: Build the Docker image
+        run: docker build . --file Dockerfile --tag image:$(date +%s)

core/templates/github/docker/lint.yml

@@ -0,0 +1,16 @@
+name: Docker Image CI
+
+on:
+  pull_request:
+    paths:
+      - "Dockerfile"
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: hadolint/hadolint-action@v1.5.0
+        with:
+          dockerfile: Dockerfile