fix dependencies between tasks

due to using an old snapshot of cue.Value, components relying on
dependent tasks were failing because of non-concretness.

Signed-off-by: Andrea Luzzardi <aluzzardi@gmail.com>

dagger/env.go

@@ -280,24 +280,30 @@ func (env *Env) Walk(ctx context.Context, fn EnvWalkFunc) (*Value, error) {
 	}
 	// Cueflow match func
 	flowMatchFn := func(v cue.Value) (cueflow.Runner, error) {
-		lg := lg.
-			With().
-			Str("path", v.Path().String()).
-			Logger()
-		ctx := lg.WithContext(ctx)
-
-		lg.Debug().Msg("Env.Walk: processing")
-		// FIXME: get directly from state Value ? Locking issue?
-		val := env.cc.Wrap(v, flowInst)
-		c, err := NewComponent(val)
-		if os.IsNotExist(err) {
-			// Not a component: skip
-			return nil, nil
-		}
-		if err != nil {
+		if _, err := NewComponent(env.cc.Wrap(v, flowInst)); err != nil {
+			if os.IsNotExist(err) {
+				// Not a component: skip
+				return nil, nil
+			}
 			return nil, err
 		}
 		return cueflow.RunnerFunc(func(t *cueflow.Task) error {
+			lg := lg.
+				With().
+				Str("path", t.Path().String()).
+				Logger()
+			ctx := lg.WithContext(ctx)
+
+			c, err := NewComponent(env.cc.Wrap(t.Value(), flowInst))
+			if err != nil {
+				return err
+			}
+			for _, dep := range t.Dependencies() {
+				lg.
+					Debug().
+					Str("dependency", dep.Path().String()).
+					Msg("dependency detected")
+			}
 			return fn(ctx, c, NewFillable(t))
 		}), nil
 	}

dagger/op.go

@@ -165,7 +165,10 @@ func (op *Op) Exec(ctx context.Context, fs FS, out *Fillable) (FS, error) {
 		Dir    string
 		Always bool
 	}
-	op.v.Decode(&cmd)
+
+	if err := op.v.Decode(&cmd); err != nil {
+		return fs, err
+	}
 	// marker for status events
 	// FIXME
 	opts = append(opts, llb.WithCustomName(op.v.Path().String()))

dagger/script.go

@@ -64,6 +64,7 @@ func (s *Script) Execute(ctx context.Context, fs FS, out *Fillable) (FS, error)
 			log.
 				Ctx(ctx).
 				Warn().
+				Err(err).
 				Int("op", idx).
 				// FIXME: tell user which inputs are missing (by inspecting references)
 				Msg("script is missing inputs and has not been fully executed")

examples/tests/dependencies/interpolation/main.cue

@@ -0,0 +1,51 @@
+package testing
+
+A: {
+	result: string
+
+	#dagger: compute: [
+		{
+			do:  "fetch-container"
+			ref: "alpine"
+		},
+		{
+			do: "exec"
+			args: ["sh", "-c", """
+				echo '{"result": "from A"}' > /tmp/out
+				""",
+			]
+			dir: "/"
+		},
+		{
+			do: "export"
+			// Source path in the container
+			source: "/tmp/out"
+			format: "json"
+		},
+	]
+}
+
+B: {
+	result: string
+
+	#dagger: compute: [
+		{
+			do:  "fetch-container"
+			ref: "alpine"
+		},
+		{
+			do: "exec"
+			args: ["sh", "-c", """
+				echo "{\\"result\\": \\"dependency \(A.result)\\"}" > /tmp/out
+				""",
+			]
+			dir: "/"
+		},
+		{
+			do: "export"
+			// Source path in the container
+			source: "/tmp/out"
+			format: "json"
+		},
+	]
+}

examples/tests/dependencies/simple/main.cue

@@ -0,0 +1,52 @@
+package testing
+
+A: {
+	result: string
+
+	#dagger: compute: [
+		{
+			do:  "fetch-container"
+			ref: "alpine"
+		},
+		{
+			do: "exec"
+			args: ["sh", "-c", """
+				echo '{"result": "from A"}' > /tmp/out
+				""",
+			]
+			dir: "/"
+		},
+		{
+			do: "export"
+			// Source path in the container
+			source: "/tmp/out"
+			format: "json"
+		},
+	]
+}
+
+B: {
+	result: string
+
+	#dagger: compute: [
+		{
+			do:  "fetch-container"
+			ref: "alpine"
+		},
+		{
+			do: "exec"
+			env: DATA: A.result
+			args: ["sh", "-c", """
+				echo "{\\"result\\": \\"dependency $DATA\\"}" > /tmp/out
+				""",
+			]
+			dir: "/"
+		},
+		{
+			do: "export"
+			// Source path in the container
+			source: "/tmp/out"
+			format: "json"
+		},
+	]
+}

examples/tests/dependencies/unmarshal/main.cue

@@ -0,0 +1,55 @@
+package testing
+
+import "encoding/json"
+
+A: {
+	string
+
+	#dagger: compute: [
+		{
+			do:  "fetch-container"
+			ref: "alpine"
+		},
+		{
+			do: "exec"
+			args: ["sh", "-c", """
+				echo '{"hello": "world"}' > /tmp/out
+				""",
+			]
+			dir: "/"
+		},
+		{
+			do: "export"
+			// Source path in the container
+			source: "/tmp/out"
+			format: "string"
+		},
+	]
+}
+
+unmarshalled: json.Unmarshal(A)
+
+B: {
+	result: string
+
+	#dagger: compute: [
+		{
+			do:  "fetch-container"
+			ref: "alpine"
+		},
+		{
+			do: "exec"
+			args: ["sh", "-c", """
+				echo "{\\"result\\": \\"unmarshalled.hello=\(unmarshalled.hello)\\"}" > /tmp/out
+				""",
+			]
+			dir: "/"
+		},
+		{
+			do: "export"
+			// Source path in the container
+			source: "/tmp/out"
+			format: "json"
+		},
+	]
+}

examples/tests/test.sh

@@ -41,6 +41,17 @@ test::compute(){
       "$dagger" "${DAGGER_BINARY_ARGS[@]}" compute "$d"/compute/success/overload/wrapped
 }
 
+test::dependencies(){
+  local dagger="$1"
+
+  test::one "Dependencies: simple direct dependency" --exit=0 --stdout='{"A":{"result":"from A"},"B":{"result":"dependency from A"}}'  \
+      "$dagger" "${DAGGER_BINARY_ARGS[@]}" compute "$d"/dependencies/simple
+  test::one "Dependencies: interpolation" --exit=0 --stdout='{"A":{"result":"from A"},"B":{"result":"dependency from A"}}'  \
+      "$dagger" "${DAGGER_BINARY_ARGS[@]}" compute "$d"/dependencies/interpolation
+  test::one "Dependencies: json.Unmarshal" --exit=0 --stdout='{"A":"{\"hello\": \"world\"}\n","B":{"result":"unmarshalled.hello=world"},"unmarshalled":{"hello":"world"}}'  \
+      "$dagger" "${DAGGER_BINARY_ARGS[@]}" compute "$d"/dependencies/unmarshal
+}
+
 test::fetchcontainer(){
   local dagger="$1"