Europa: integrate core packages, separate universe

Signed-off-by: Solomon Hykes <solomon@dagger.io>

europa-universe/alpine/alpine.cue

@@ -0,0 +1,36 @@
+// Base package for Alpine Linux
+package alpine
+
+import (
+	"universe.dagger.io/docker"
+)
+
+// Default Alpine version
+let defaultVersion = "3.13.5@sha256:69e70a79f2d41ab5d637de98c1e0b055206ba40a8145e7bddb55ccc04e13cf8f"
+
+// Build an Alpine Linux container image
+#Build: {
+	// Alpine version to install
+	version: string | *defaultVersion
+
+	// List of packages to install
+	packages: [pkgName=string]: version: string | *""
+
+	docker.#Build & {
+		steps: [
+			docker.#Pull & {
+				source: "index.docker.io/alpine:\(version)"
+			},
+			for pkgName, pkg in packages {
+				run: cmd: {
+					name: "apk"
+					args: ["add", "\(pkgName)\(version)"]
+					flags: {
+						"-U":         true
+						"--no-cache": true
+					}
+				}
+			},
+		]
+	}
+}

europa-universe/alpine/tests/simple/simple.cue

@@ -0,0 +1,38 @@
+package alpine
+
+import (
+	"universe.dagger.io/docker"
+)
+
+TestImageVersion: {
+	build: #Build & {
+		// install an old version on purpose
+		version: "3.10.9"
+	}
+
+	check: docker.#Run & {
+		image: build.output
+		output: files: "/etc/alpine-release": contents: "3.10.9"
+	}
+}
+
+TestPackageInstall: {
+	build: #Build & {
+		packages: {
+			jq: {}
+			curl: {}
+		}
+	}
+
+	check: docker.#Run & {
+		script: """
+			jq --version > /jq-version.txt
+			curl --version > /curl-version.txt
+			"""
+
+		output: files: {
+			"/jq-version.txt": contents:   "FIXME"
+			"/curl-version.txt": contents: "FIXME"
+		}
+	}
+}