feat: add a devcontainer for easier development

This change adds a devcontainer that properly sets up a test environment
such that a user has a working `cscli` and `crowdsec` command for their
hub checkout.  This makes it much easier to developer parsers in this
repository, greatly reducing the barrier to entry.

This change also adds a workflow to make sure the devcontainer can
build.  This could be further extended to also run tests in the
devcontainer.

I verified this works by running the example test command in the
`README.md`:
```sh
cscli hubtest run dovecot-logs
INFO[26-02-2025 19:00:00] Running test 'dovecot-logs'                  
INFO[26-02-2025 19:00:03] Test 'dovecot-logs' passed successfully (387 assertions) 
───────────────────────
 Test           Result 
───────────────────────
 dovecot-logs   ✅     
───────────────────────
```

Additionally, I ran all tests with `cscli hubtest run --all`, which
outputted this: https://gist.github.com/sdwilsh/6ed59b6904dac9cabbea63c55567c070

.devcontainer/Dockerfile

@@ -0,0 +1,27 @@
+# The `builder` fetches the latest crowdsec release and untars it so it can be
+# used by the actual devcontainer.
+FROM alpine:latest AS builder
+WORKDIR /app
+RUN wget -q https://github.com/crowdsecurity/crowdsec/releases/latest/download/crowdsec-release.tgz \
+    && tar xvzf crowdsec-release.tgz \
+    && mv $(find -name 'crowdsec-v*') /crowdsec
+
+#
+# The actual devcontainer.
+#
+FROM mcr.microsoft.com/devcontainers/base:debian
+
+# Install Required Dependencies
+RUN apt-get update \
+  && apt-get install -y --no-install-recommends \
+    yq \
+  && apt-get clean \
+  && rm -rf /var/lib/apt/lists/*
+
+# Install crowdsec
+COPY --from=builder /crowdsec /workspaces/crowdsec
+RUN chown 1000:1000 -R /workspaces/crowdsec
+
+# Install wrapper scripts.
+COPY bin/crowdsec /usr/local/bin/crowdsec
+COPY bin/cscli /usr/local/bin/cscli

.devcontainer/bin/crowdsec

@@ -0,0 +1,8 @@
+#!/usr/bin/env sh
+
+set -e
+
+# This is a lightweight wrapper around the test environment's crowdsec command.
+# It uses a configuration that is setup to "just work" from the devcontainer.
+
+/workspaces/crowdsec/tests/crowdsec -c /workspaces/crowdsec/tests/dev.yaml $@

.devcontainer/bin/cscli

@@ -0,0 +1,8 @@
+#!/usr/bin/env sh
+
+set -e
+
+# This is a lightweight wrapper around the test environment's cscli command.
+# It uses a configuration that is setup to "just work" from the devcontainer.
+
+/workspaces/crowdsec/tests/cscli -c /workspaces/crowdsec/tests/dev.yaml $@

.devcontainer/devcontainer.json

@@ -0,0 +1,9 @@
+{
+	"name": "CrowdSec Hub",
+	"build": {
+		"dockerfile": "Dockerfile"
+	},
+	"postCreateCommand": "sh -f .devcontainer/postCreate.sh",
+	"workspaceFolder": "/workspaces/hub",
+	"workspaceMount": "source=${localWorkspaceFolder},target=/workspaces/hub,type=bind"
+}

.devcontainer/postCreate.sh

@@ -0,0 +1,27 @@
+#!/usr/bin/env sh
+
+set -e
+
+# Setup the test environment.
+cd /workspaces/crowdsec/
+./test_env.sh
+cd tests/
+
+# Update config to point to correct paths for this devcontainer.
+yq -iy '.config_paths.hub_dir = "/workspaces/hub/"' dev.yaml
+yq -iy '.config_paths.index_path = "/workspaces/hub/.index"' dev.yaml
+
+# As documented in https://github.com/crowdsecurity/crowdsec/issues/3183,
+# running ./test_env.sh sets a bunch of relative paths with simply do not work
+# as we need them to in a devcontainer.  The following lines set absolute paths
+# that do work.
+yq -iy '.api.client.credentials_path = "/workspaces/crowdsec/tests/config/local_api_credentials.yaml"' dev.yaml
+yq -iy '.api.server.console_path = "/workspaces/crowdsec/tests/config/console.yaml"' dev.yaml
+yq -iy '.api.server.online_client.credentials_path = "/workspaces/crowdsec/tests/config/online_api_credentials.yaml"' dev.yaml
+yq -iy '.api.server.profiles_path = "/workspaces/crowdsec/tests/config/profiles.yaml"' dev.yaml
+yq -iy '.config_paths.config_dir = "/workspaces/crowdsec/tests/config/"' dev.yaml
+yq -iy '.config_paths.data_dir = "/workspaces/crowdsec/tests/data/"' dev.yaml
+yq -iy '.config_paths.notification_dir = "/workspaces/crowdsec/tests/notifications/"' dev.yaml
+yq -iy '.config_paths.plugin_dir = "/workspaces/crowdsec/tests/plugins/"' dev.yaml
+yq -iy '.crowdsec_service.acquisition_path = "/workspaces/crowdsec/tests/config/acquis.yaml"' dev.yaml
+yq -iy '.db_config.db_path = "/workspaces/crowdsec/tests/data/crowdsec.db"' dev.yaml

.github/workflows/devcontainer.yml

@@ -0,0 +1,22 @@
+name: Build Developer Container
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - .devcontainer/**
+  pull_request:
+    branches:
+      - master
+    paths:
+      - .devcontainer/**
+
+jobs: 
+  devcontainer-build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: checkout repo
+        uses: actions/checkout@v4
+
+      - name: Build devcontainer image
+        uses: devcontainers/[email protected]