examples/jamstack: implemented backend deployment running on ecs

Signed-off-by: Sam Alba <sam.alba@gmail.com>

examples/jamstack/ecr_image.cue

@@ -0,0 +1,55 @@
+package main
+
+import (
+	"dagger.io/dagger"
+	"dagger.io/dagger/op"
+	"dagger.io/aws"
+	"dagger.io/aws/ecr"
+)
+
+// Build an image and push it to ECR
+#ECRImage: {
+	source: dagger.#Artifact
+	// Path of the Dockerfile
+	dockerfilePath?: string
+	repository:      string
+	tag:             string
+	awsConfig:       aws.#Config
+	buildArgs: [string]: string
+
+	pushTarget: "\(repository):\(tag)"
+
+	// Build the image
+	buildImage: op.#DockerBuild & {
+		context: source
+		if dockerfilePath != _|_ {
+			"dockerfilePath": dockerfilePath
+		}
+		buildArg: buildArgs
+	}
+
+	// Use these credentials to push
+	ecrCreds: ecr.#Credentials & {
+		config: awsConfig
+		target: pushTarget
+	}
+
+	push: #up: [
+		op.#DockerBuild & {
+			context: source
+			if dockerfilePath != _|_ {
+				"dockerfilePath": dockerfilePath
+			}
+			buildArg: buildArgs
+		},
+		op.Export & {
+			format: "string"
+			source: op.#PushContainer & {
+				ref: pushTarget
+			}
+		},
+	]
+
+	// FIXME: ref does not include the sha256: https://github.com/dagger/dagger/issues/303
+	ref: pushTarget
+}