engine: graph: Allow send/recv to work with autogrouped resources

We've previously not received a value from within an autogrouped
resource. It turns out this would be quite useful, and so this patch
implements the additional plumbing and testing so that this works!

Testing that an autogrouped resource can still send values has not been
done at this time.

engine/graph/actions.go

@@ -112,24 +112,38 @@ func (obj *Engine) Process(ctx context.Context, vertex pgraph.Vertex) error {
 
 	// sendrecv!
 	// connect any senders to receivers and detect if values changed
+	// this actually checks and sends into resource trees recursively...
 	if res, ok := vertex.(engine.RecvableRes); ok {
 		if updated, err := obj.SendRecv(res); err != nil {
 			return errwrap.Wrapf(err, "could not SendRecv")
 		} else if len(updated) > 0 {
-			for _, changed := range updated {
-				if changed { // at least one was updated
+			for r, m := range updated { // map[engine.RecvableRes]map[string]bool
+				v, ok := r.(pgraph.Vertex)
+				if !ok {
+					continue
+				}
+				_, stateExists := obj.state[v] // autogrouped children probably don't have a state
+				if !stateExists {
+					continue
+				}
+				for _, changed := range m {
+					if !changed {
+						continue
+					}
+					// if changed == true, at least one was updated
 					// invalidate cache, mark as dirty
-					obj.state[vertex].tuid.StopTimer()
-					obj.state[vertex].isStateOK = false
-					break
-				}
+					obj.state[v].tuid.StopTimer()
+					obj.state[v].isStateOK = false
+					//break // we might have more vertices now
 				}
+
 				// re-validate after we change any values
-			if err := engine.Validate(res); err != nil {
+				if err := engine.Validate(r); err != nil {
 					return errwrap.Wrapf(err, "failed Validate after SendRecv")
 				}
 			}
 		}
+	}
 
 	var ok = true
 	var applied = false              // did we run an apply?

engine/graph/sendrecv.go

@@ -20,6 +20,8 @@ package graph
 import (
 	"fmt"
 	"reflect"
+	"sort"
+	"strings"
 
 	"github.com/purpleidea/mgmt/engine"
 	engineUtil "github.com/purpleidea/mgmt/engine/util"
@@ -29,17 +31,66 @@ import (
 
 // SendRecv pulls in the sent values into the receive slots. It is called by the
 // receiver and must be given as input the full resource struct to receive on.
-// It applies the loaded values to the resource.
-func (obj *Engine) SendRecv(res engine.RecvableRes) (map[string]bool, error) {
-	recv := res.Recv()
+// It applies the loaded values to the resource. It is called recursively, as it
+// recurses into any grouped resources found within the first receiver. It
+// returns a map of resource pointer, to resource field key, to changed boolean.
+func (obj *Engine) SendRecv(res engine.RecvableRes) (map[engine.RecvableRes]map[string]bool, error) {
+	updated := make(map[engine.RecvableRes]map[string]bool) // list of updated keys
 	if obj.Debug {
-		// NOTE: this could expose private resource data like passwords
-		obj.Logf("%s: SendRecv: %+v", res, recv)
+		obj.Logf("SendRecv: %s", res) // receiving here
+	}
+	if groupableRes, ok := res.(engine.GroupableRes); ok {
+		for _, x := range groupableRes.GetGroup() { // grouped elements
+			recvableRes, ok := x.(engine.RecvableRes)
+			if !ok {
+				continue
+			}
+			if obj.Debug {
+				obj.Logf("SendRecv: %s: grouped: %s", res, x) // receiving here
+			}
+			// We need to recurse here so that autogrouped resources
+			// inside autogrouped resources would work... In case we
+			// work correctly. We just need to make sure that things
+			// are grouped in the correct order, but that is not our
+			// problem! Recurse and merge in the changed results...
+			innerUpdated, err := obj.SendRecv(recvableRes)
+			if err != nil {
+				return nil, errwrap.Wrapf(err, "recursive SendRecv error")
+			}
+			for r, m := range innerUpdated { // res ptr, map
+				if _, exists := updated[r]; !exists {
+					updated[r] = make(map[string]bool)
+				}
+				for s, b := range m {
+					// don't overwrite in case one exists...
+					if old, exists := updated[r][s]; exists {
+						b = b || old // unlikely i think
+					}
+					updated[r][s] = b
+				}
+			}
+		}
+	}
+
+	recv := res.Recv()
+	keys := []string{}
+	for k := range recv { // map[string]*Send
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+	if obj.Debug && len(keys) > 0 {
+		// NOTE: this could expose private resource data like passwords
+		obj.Logf("SendRecv: %s recv: %+v", res, strings.Join(keys, ", "))
 	}
-	var updated = make(map[string]bool) // list of updated keys
 	var err error
-	for k, v := range recv {
-		updated[k] = false // default
+	for k, v := range recv { // map[string]*Send
+		// v.Res // SendableRes // a handle to the resource which is sending a value
+		// v.Key // string      // the key in the resource that we're sending
+		if _, exists := updated[res]; !exists {
+			updated[res] = make(map[string]bool)
+		}
+
+		updated[res][k] = false // default
 		v.Changed = false       // reset to the default
 
 		var st interface{} = v.Res // old style direct send/recv
@@ -167,7 +218,7 @@ func (obj *Engine) SendRecv(res engine.RecvableRes) (map[string]bool, error) {
 			continue
 		}
 		//dest.Set(orig)  // do it for all types that match
-		updated[k] = true // we updated this key!
+		updated[res][k] = true // we updated this key!
 		v.Changed = true       // tag this key as updated!
 		obj.Logf("SendRecv: %s.%s -> %s.%s", v.Res, v.Key, res, k)
 	}

examples/lang/sendrecv-autogroup.mcl

@@ -0,0 +1,32 @@
+# send/recv of value1.any into print1.msg works!
+value "value1" {
+	any => "i am value1",
+}
+print "print1" {
+	msg => "i am print1",
+
+	Meta:autogroup => false,
+}
+Value["value1"].any -> Print["print1"].msg
+
+# One of these will be autogrouped into the other! The inner one can receive!
+# send/recv from value2.any into print2.msg works
+# send/recv from value3.any into (the usually autogrouped) print3 works too!
+value "value2" {
+	any => "i am value2",
+}
+value "value3" {
+	any => "i am value3",
+}
+print "print2" {
+	msg => "i am print2",
+
+	Meta:autogroup => true,
+}
+print "print3" {
+	msg => "i am print3",
+
+	Meta:autogroup => true,
+}
+Value["value2"].any -> Print["print2"].msg
+Value["value3"].any -> Print["print3"].msg

lang/interpret_test.go

@@ -36,6 +36,7 @@ import (
 	"github.com/purpleidea/mgmt/engine"
 	"github.com/purpleidea/mgmt/engine/graph"
 	"github.com/purpleidea/mgmt/engine/graph/autoedge"
+	"github.com/purpleidea/mgmt/engine/graph/autogroup"
 	"github.com/purpleidea/mgmt/engine/local"
 	engineUtil "github.com/purpleidea/mgmt/engine/util"
 	"github.com/purpleidea/mgmt/etcd"
@@ -50,6 +51,7 @@ import (
 	"github.com/purpleidea/mgmt/lang/unification"
 	"github.com/purpleidea/mgmt/pgraph"
 	"github.com/purpleidea/mgmt/util"
+	"github.com/purpleidea/mgmt/util/errwrap"
 
 	"github.com/kylelemons/godebug/pretty"
 	"github.com/spf13/afero"
@@ -2061,6 +2063,15 @@ func TestAstFunc3(t *testing.T) {
 
 			// TODO: apply the global metaparams to the graph
 
+			// XXX: can we change this into a ge.Apply operation?
+			// run autogroup; modifies the graph
+			if err := ge.AutoGroup(&autogroup.NonReachabilityGrouper{}); err != nil {
+				//ge.Abort() // delete graph
+				t.Errorf("test #%d: FAIL", index)
+				t.Errorf("test #%d: error running autogrouping: %+v", index, err)
+				return
+			}
+
 			fastPause := false
 			ge.Pause(fastPause) // sync
 			if err := ge.Commit(); err != nil {
@@ -2091,34 +2102,24 @@ func TestAstFunc3(t *testing.T) {
 			t.Logf("test #%d: graph: %+v", index, ngraph)
 			str := strings.Trim(ngraph.Sprint(), "\n") // text format of output graph
 
-			for i, v := range ngraph.Vertices() {
+			for _, v := range ngraph.Vertices() {
 				res, ok := v.(engine.Res)
 				if !ok {
 					t.Errorf("test #%d: FAIL\n\n", index)
 					t.Logf("test #%d: unexpected non-resource: %+v", index, v)
 					return
 				}
-				m, err := engineUtil.ResToParamValues(res)
+
+				s, err := stringResFields(res)
 				if err != nil {
 					t.Errorf("test #%d: FAIL\n\n", index)
 					t.Logf("test #%d: can't read resource: %+v", index, err)
 					return
 				}
-				if i == 0 {
-					str += "\n"
-				}
-				keys := []string{}
-				for k := range m {
-					keys = append(keys, k)
-				}
-				sort.Strings(keys) // sort for determinism
-				for _, field := range keys {
-					v := m[field]
-					str += fmt.Sprintf("Field: %s[%s].%s = %s\n", res.Kind(), res.Name(), field, v)
-				}
-				if i < len(ngraph.Vertices()) {
+				if str != "" {
 					str += "\n"
 				}
+				str += s
 			}
 
 			if expstr == magicEmpty {
@@ -2162,3 +2163,40 @@ func TestAstFunc3(t *testing.T) {
 		t.Skip("skipping all tests...")
 	}
 }
+
+// stringResFields is a helper function to store a resource graph as a text
+// format for test comparisons.
+func stringResFields(res engine.Res) (string, error) {
+	m, err := engineUtil.ResToParamValues(res)
+	if err != nil {
+		return "", errwrap.Wrapf(err, "can't read resource %s", res)
+	}
+	str := ""
+	keys := []string{}
+	for k := range m {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys) // sort for determinism
+	for _, field := range keys {
+		v := m[field]
+		str += fmt.Sprintf("Field: %s[%s].%s = %s\n", res.Kind(), res.Name(), field, v)
+	}
+
+	groupableRes, ok := res.(engine.GroupableRes)
+	if !ok {
+		return str, nil
+	}
+	for _, x := range groupableRes.GetGroup() { // grouped elements
+		s, err := stringResFields(x) // recurse
+		if err != nil {
+			return "", err
+		}
+		// add a prefix to each line?
+		s = strings.Trim(s, "\n") // trim trailing newlines
+		for _, f := range strings.Split(s, "\n") {
+			str += fmt.Sprintf("Group: %s: ", res) + f + "\n"
+		}
+		//str += s
+	}
+	return str, nil
+}

lang/interpret_test/TestAstFunc3/sendrecv-autogroup.txtar

@@ -0,0 +1,48 @@
+-- main.mcl --
+# send/recv of value1.any into print1.msg works!
+value "value1" {
+	any => "i am value1",
+}
+print "print1" {
+	msg => "i am print1",
+
+	Meta:autogroup => false,
+}
+Value["value1"].any -> Print["print1"].msg
+
+# One of these will be autogrouped into the other! The inner one can receive!
+# send/recv from value2.any into print2.msg works
+# send/recv from value3.any into (the usually autogrouped) print3 works too!
+value "value2" {
+	any => "i am value2",
+}
+value "value3" {
+	any => "i am value3",
+}
+print "print2" {
+	msg => "i am print2",
+
+	Meta:autogroup => true,
+}
+print "print3" {
+	msg => "i am print3",
+
+	Meta:autogroup => true,
+}
+Value["value2"].any -> Print["print2"].msg
+Value["value3"].any -> Print["print3"].msg
+-- OUTPUT --
+Edge: value[value1] -> print[print1] # value[value1] -> print[print1]
+Edge: value[value2] -> print[print2] # value[value2] -> print[print2]
+Edge: value[value3] -> print[print2] # value[value3] -> print[print3]
+Field: print[print1].Msg = "i am value1"
+Field: print[print2].Msg = "i am value2"
+Field: value[value1].Any = "i am value1"
+Field: value[value2].Any = "i am value2"
+Field: value[value3].Any = "i am value3"
+Group: print[print2]: Field: print[print3].Msg = "i am value3"
+Vertex: print[print1]
+Vertex: print[print2]
+Vertex: value[value1]
+Vertex: value[value2]
+Vertex: value[value3]