Europa: remove implemented engine definitions from spec mock

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

stdlib/europa/dagger/engine/fs.cue

@@ -1,20 +1,33 @@
 package engine
 
+// Read a file from a filesystem tree
 #ReadFile: {
 	_type: "ReadFile"
 
-	input:    #FS
-	path:     string
+	// Filesystem tree holding the file
+	input: #FS
+	// Path of the file to read
+	path: string
+	// Contents of the file
 	contents: string
-	output:   #FS
+	// Output filesystem tree
+	// FIXME: this is a no-op. No output needed.
+	output: #FS
 }
 
+// Write a file to a filesystem tree, creating it if needed
 #WriteFile: {
 	_type: "WriteFile"
 
-	input:    #FS
-	path:     string
+	// Input filesystem tree
+	input: #FS
+	// Path of the file to write
+	path: string
+	// Contents to write
 	contents: string
-	mode:     int
-	output:   #FS
+	// Permissions of the file
+	// FIXME: rename to 'permissions' for consistency
+	mode: int
+	// Output filesystem tree
+	output: #FS
 }

stdlib/europa/dagger/engine/spec/engine/fs.cue

@@ -1,10 +1,5 @@
 package engine
 
-// A filesystem state
-#FS: {
-	$dagger: fs: _id: string
-}
-
 // Produce an empty directory
 // FIXME: replace with a null value for #FS?
 #Scratch: {
@@ -13,23 +8,9 @@ package engine
 	output: #FS
 }
 
-#ReadFile: {
-	$dagger: task: _name: "ReadFile"
+#ReadFile: $dagger: task: _name: "ReadFile"
 
-	input:    #FS
-	path:     string
-	contents: string
-	output:   #FS
-}
-
-#WriteFile: {
-	$dagger: task: _name: "WriteFile"
-
-	input:    #FS
-	path:     string
-	contents: string
-	output:   #FS
-}
+#WriteFile: $dagger: task: _name: "WriteFile"
 
 // Create a directory
 #Mkdir: {
@@ -39,8 +20,7 @@ package engine
 
 	// Path of the directory
 	path: string
-	// FIXME: this is not very dev friendly, as Cue does not support octal notation.
-	// What is a better option?
+	// FIXME: permissions?
 	mode: int
 	// Create parent directories as needed?
 	parents: *true | false

stdlib/europa/dagger/engine/spec/engine/image.cue

@@ -1,14 +1,5 @@
 package engine
 
-// Container image config
-// See [OCI](https://www.opencontainers.org)
-#ImageConfig: {
-	env?: [...string]
-	user?: string
-	command?: [...string]
-	// FIXME
-}
-
 // Upload a container image to a remote repository
 #Push: {
 	$dagger: task: _name: "Push"
@@ -34,36 +25,7 @@ package engine
 }
 
 // Download a container image from a remote repository
-#Pull: {
-	$dagger: task: _name: "Pull"
-
-	// Repository source ref
-	source: #Ref
-	// Authentication
-	auth: [...{
-		target:   string
-		username: string
-		secret:   string | #Secret
-	}]
-
-	// Root filesystem of downloaded image
-	output: #FS
-
-	// Complete ref of downloaded image (including digest)
-	result: #Ref
-
-	// Downloaded container image config
-	config: #ImageConfig
-}
-
-// A ref is an address for a remote container image
-//
-// Examples:
-//   - "index.docker.io/dagger"
-//   - "dagger"
-//   - "index.docker.io/dagger:latest"
-//   - "index.docker.io/dagger:latest@sha256:a89cb097693dd354de598d279c304a1c73ee550fbfff6d9ee515568e0c749cfe"
-#Ref: string
+#Pull: $dagger: task: _name: "Pull"
 
 // Build a container image using buildkit
 // FIXME: rename to #Dockerfile to clarify scope

stdlib/europa/dagger/engine/spec/engine/secret.cue

@@ -1,6 +0,0 @@
-package engine
-
-// An external secret
-#Secret: {
-	$dagger: secret: _id: string
-}

stdlib/europa/dagger/engine/spec/engine/service.cue

@@ -1,7 +0,0 @@
-package engine
-
-// An external network service
-// FIXME: rename to endpoint?
-#Service: {
-	$dagger: service: _id: string
-}

stdlib/europa/dagger/engine/spec/engine/stream.cue

@@ -1,6 +0,0 @@
-package engine
-
-// A stream of bytes
-#Stream: {
-	$dagger: stream: _id: string
-}