Use ShortestPathStable and always add graphstate vertices

These resolve engine behaving non-deterministically

Author: gordon-klotho

.vscode/settings.json

@@ -17,5 +17,6 @@
     "pkg/engine": true,
     "pkg/knowledge_base": true,
     "**/node_modules": true
-  }
+  },
+  "go.testTimeout": "5m"
 }

compare.sh

@@ -0,0 +1,23 @@
+#!/bin/sh
+
+# This script takes in an input yaml, and runs the engine on it twice.
+# It saves the log output in out.log and out2.log.
+# It then filters the logs for important messages and outputs to out.queue.log and out2.queue.log.
+# These files can then be diffed to see if the engine is behaving the same way on the same input.
+
+file=$1
+if [ ! -f "$file" ]; then
+    file="./pkg/engine2/testdata/$1"
+fi
+
+rm out.log out2.log
+export NO_COLOR=1
+export COLUMNS=80
+go run ./cmd/engine Run -i "$file" -o "./out/$(basename $file .yaml)" -v 2> out.log
+sleep 2
+go run ./cmd/engine Run -i "$file" -o "./out/$(basename $file .yaml)2" -v 2> out2.log
+
+rm out.queue.log out2.queue.log
+grep -E -e 'op: dequeue|eval|poll-deps' -e 'Satisfied' out.log > out.queue.log
+grep -E -e 'op: dequeue|eval|poll-deps' -e 'Satisfied' out2.log > out2.queue.log
+

go.mod

@@ -23,6 +23,7 @@ require (
 	github.com/pborman/ansi v1.0.0
 	github.com/pelletier/go-toml/v2 v2.0.8-0.20230509155657-d34104d49374
 	github.com/pkg/errors v0.9.1
+	github.com/r3labs/diff v1.1.0
 	github.com/schollz/progressbar/v3 v3.13.0
 	github.com/smacker/go-tree-sitter v0.0.0-20220209044044-0d3022e933c3
 	github.com/spf13/cobra v1.6.1
@@ -47,15 +48,14 @@ require (
 	github.com/kr/pretty v0.3.0 // indirect
 	github.com/mattn/go-sqlite3 v2.0.3+incompatible // indirect
 	github.com/mitchellh/colorstring v0.0.0-20190213212951-d06e56a500db // indirect
-	github.com/r3labs/diff v1.1.0 // indirect
 	github.com/rivo/uniseg v0.4.4 // indirect
 	golang.org/x/mod v0.9.0 // indirect
 	golang.org/x/oauth2 v0.4.0 // indirect
 	k8s.io/client-go v0.26.0 // indirect
 )
 
 replace (
-	github.com/dominikbraun/graph => github.com/klothoplatform/graph v0.24.6
+	github.com/dominikbraun/graph => github.com/klothoplatform/graph v0.24.7
 
 	// github.com/dominikbraun/graph => github.com/klothoplatform/graph v0.24.3
 	github.com/smacker/go-tree-sitter => github.com/klothoplatform/go-tree-sitter v0.1.1

go.sum

@@ -383,8 +383,8 @@ github.com/klauspost/compress v1.15.14 h1:i7WCKDToww0wA+9qrUZ1xOjp218vfFo3nTU6UH
 github.com/klauspost/compress v1.15.14/go.mod h1:QPwzmACJjUTFsnSHH934V6woptycfrDDJnH7hvFVbGM=
 github.com/klothoplatform/go-tree-sitter v0.1.1 h1:UO9bDCP6jJfKHUPv0P+8wLM6FJ4tCRNu3Hj2EQE51wk=
 github.com/klothoplatform/go-tree-sitter v0.1.1/go.mod h1:q99oHDsbP0xRwmn7Vmob8gbSMNyvJ83OauXPSuHQuKE=
-github.com/klothoplatform/graph v0.24.6 h1:eLI4Pr9aqk6trjqbxlX3K9aOCdAnTxO+8Nc/wEpZSlw=
-github.com/klothoplatform/graph v0.24.6/go.mod h1:yOjYyogZLY1LSG9E33JWZJiq5k83Qy2C6POAuiViluc=
+github.com/klothoplatform/graph v0.24.7 h1:eE3or9a8a5xgk0WaQPYVEUzbvaXafbc38+PpYpl3t1E=
+github.com/klothoplatform/graph v0.24.7/go.mod h1:yOjYyogZLY1LSG9E33JWZJiq5k83Qy2C6POAuiViluc=
 github.com/klothoplatform/yaml/v3 v3.0.1 h1:9POX/TEuMqoXsMJ6ypU2FdaRtnt47bxx+klOQ0PSuys=
 github.com/klothoplatform/yaml/v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=

pkg/construct2/dot.go

@@ -0,0 +1,116 @@
+package construct2
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"sort"
+
+	"github.com/klothoplatform/klotho/pkg/dot"
+)
+
+func dotAttributes(r *Resource) map[string]string {
+	a := make(map[string]string)
+	a["label"] = r.ID.String()
+	a["shape"] = "box"
+	return a
+}
+
+func dotEdgeAttributes(e ResourceEdge) map[string]string {
+	a := make(map[string]string)
+	_ = e.Source.WalkProperties(func(path PropertyPath, nerr error) error {
+		v := path.Get()
+		if v == e.Target.ID {
+			a["label"] = path.String()
+			return StopWalk
+		}
+		return nil
+	})
+	return a
+}
+
+func GraphToDOT(g Graph, out io.Writer) error {
+	ids, err := ToplogicalSort(g)
+	if err != nil {
+		return err
+	}
+	nodes, err := ResolveIds(g, ids)
+	if err != nil {
+		return err
+	}
+	var errs error
+	printf := func(s string, args ...any) {
+		_, err := fmt.Fprintf(out, s, args...)
+		errs = errors.Join(errs, err)
+	}
+	printf(`digraph {
+  rankdir = TB
+`)
+	for _, n := range nodes {
+		printf("  %q%s\n", n.ID, dot.AttributesToString(dotAttributes(n)))
+	}
+
+	topoIndex := func(id ResourceId) int {
+		for i, id2 := range ids {
+			if id2 == id {
+				return i
+			}
+		}
+		return -1
+	}
+	edges, err := g.Edges()
+	if err != nil {
+		return err
+	}
+	sort.Slice(edges, func(i, j int) bool {
+		ti, tj := topoIndex(edges[i].Source), topoIndex(edges[j].Source)
+		if ti != tj {
+			return ti < tj
+		}
+		ti, tj = topoIndex(edges[i].Target), topoIndex(edges[j].Target)
+		return ti < tj
+	})
+	for _, e := range edges {
+		edge, err := g.Edge(e.Source, e.Target)
+		if err != nil {
+			errs = errors.Join(errs, err)
+			continue
+		}
+		printf("  %q -> %q%s\n", e.Source, e.Target, dot.AttributesToString(dotEdgeAttributes(edge)))
+	}
+	printf("}\n")
+	return errs
+}
+
+func GraphToSVG(g Graph, prefix string) error {
+	if debugDir := os.Getenv("KLOTHO_DEBUG_DIR"); debugDir != "" {
+		prefix = filepath.Join(debugDir, prefix)
+	}
+	f, err := os.Create(prefix + ".gv")
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	dotContent := new(bytes.Buffer)
+	err = GraphToDOT(g, io.MultiWriter(f, dotContent))
+	if err != nil {
+		return fmt.Errorf("could not render graph to file %s: %v", prefix+".gv", err)
+	}
+
+	svgContent, err := dot.ExecPan(bytes.NewReader(dotContent.Bytes()))
+	if err != nil {
+		return fmt.Errorf("could not run 'dot' for %s: %v", prefix+".gv", err)
+	}
+
+	svgFile, err := os.Create(prefix + ".gv.svg")
+	if err != nil {
+		return fmt.Errorf("could not create file %s: %v", prefix+".gv.svg", err)
+	}
+	defer svgFile.Close()
+	_, err = fmt.Fprint(svgFile, svgContent)
+	return err
+}

pkg/construct2/paths.go

@@ -4,7 +4,6 @@ import (
 	"errors"
 	"fmt"
 	"math"
-	"sort"
 	"strings"
 
 	"github.com/dominikbraun/graph"
@@ -120,37 +119,38 @@ func bellmanFord(g Graph, source ResourceId, skipEdge func(Edge) bool) (*bellman
 	}
 	dist[source] = 0
 
-	// Sort the keys to ensure deterministic results. It adds +O(N) to the runtime, but
-	// when it's already O(N * E), it doesn't matter.
-	sortedKeys := make([]ResourceId, 0, len(adjacencyMap))
-	for key := range adjacencyMap {
-		sortedKeys = append(sortedKeys, key)
-	}
-	sort.Sort(SortedIds(sortedKeys))
-
 	for i := 0; i < len(adjacencyMap)-1; i++ {
-		for _, key := range sortedKeys {
-			edges := adjacencyMap[key]
+		for key, edges := range adjacencyMap {
 			for _, edge := range edges {
 				if skipEdge(edge) {
 					continue
 				}
-				newDist := dist[key] + edge.Properties.Weight
+				edgeWeight := edge.Properties.Weight
+				if !g.Traits().IsWeighted {
+					edgeWeight = 1
+				}
+
+				newDist := dist[key] + edgeWeight
 				if newDist < dist[edge.Target] {
 					dist[edge.Target] = newDist
 					prev[edge.Target] = key
+				} else if newDist == dist[edge.Target] && ResourceIdLess(key, prev[edge.Target]) {
+					prev[edge.Target] = key
 				}
 			}
 		}
 	}
 
-	for _, key := range sortedKeys {
-		edges := adjacencyMap[key]
+	for _, edges := range adjacencyMap {
 		for _, edge := range edges {
 			if skipEdge(edge) {
 				continue
 			}
-			if newDist := dist[edge.Source] + edge.Properties.Weight; newDist < dist[edge.Target] {
+			edgeWeight := edge.Properties.Weight
+			if !g.Traits().IsWeighted {
+				edgeWeight = 1
+			}
+			if newDist := dist[edge.Source] + edgeWeight; newDist < dist[edge.Target] {
 				return nil, errors.New("graph contains a negative-weight cycle")
 			}
 		}

pkg/engine2/cli.go

@@ -8,12 +8,14 @@ import (
 	"reflect"
 	"runtime/pprof"
 	"strings"
+	"sync"
 
 	"github.com/iancoleman/strcase"
 	"github.com/klothoplatform/klotho/pkg/analytics"
 	"github.com/klothoplatform/klotho/pkg/closenicely"
 	construct "github.com/klothoplatform/klotho/pkg/construct2"
 	"github.com/klothoplatform/klotho/pkg/engine2/constraints"
+	"github.com/klothoplatform/klotho/pkg/engine2/solution_context"
 	"github.com/klothoplatform/klotho/pkg/io"
 	knowledgebase "github.com/klothoplatform/klotho/pkg/knowledge_base2"
 	"github.com/klothoplatform/klotho/pkg/knowledge_base2/reader"
@@ -264,8 +266,11 @@ func (em *EngineMain) RunEngine(cmd *cobra.Command, args []string) error {
 	if err != nil {
 		return err
 	}
-	var input construct.YamlGraph
+
+	context := &EngineContext{}
+
 	if architectureEngineCfg.inputGraph != "" {
+		var input FileFormat
 		zap.S().Info("Loading input graph")
 		inputF, err := os.Open(architectureEngineCfg.inputGraph)
 		if err != nil {
@@ -276,25 +281,29 @@ func (em *EngineMain) RunEngine(cmd *cobra.Command, args []string) error {
 		if err != nil {
 			return err
 		}
+		context.InitialState = input.Graph
+		if architectureEngineCfg.constraints == "" {
+			context.Constraints = input.Constraints
+		}
 	} else {
-		input.Graph = construct.NewGraph()
+		context.InitialState = construct.NewGraph()
 	}
 	zap.S().Info("Loading constraints")
 
-	runConstraints, err := constraints.LoadConstraintsFromFile(architectureEngineCfg.constraints)
-	if err != nil {
-		return errors.Errorf("failed to load constraints: %s", err.Error())
-	}
-	context := &EngineContext{
-		InitialState: input.Graph,
-		Constraints:  runConstraints,
+	if architectureEngineCfg.constraints != "" {
+		runConstraints, err := constraints.LoadConstraintsFromFile(architectureEngineCfg.constraints)
+		if err != nil {
+			return errors.Errorf("failed to load constraints: %s", err.Error())
+		}
+		context.Constraints = runConstraints
 	}
 
 	zap.S().Info("Running engine")
 	err = em.Engine.Run(context)
 	if err != nil {
 		return errors.Errorf("failed to run engine: %s", err.Error())
 	}
+	writeDebugGraphs(context.Solutions[0])
 	zap.S().Info("Engine finished running... Generating views")
 	var files []io.File
 	files, err = em.Engine.VisualizeViews(context.Solutions[0])
@@ -407,3 +416,23 @@ func (em *EngineMain) GetValidEdgeTargets(cmd *cobra.Command, args []string) err
 	}
 	return nil
 }
+
+func writeDebugGraphs(sol solution_context.SolutionContext) {
+	wg := sync.WaitGroup{}
+	wg.Add(2)
+	go func() {
+		defer wg.Done()
+		err := construct.GraphToSVG(sol.DataflowGraph(), "dataflow")
+		if err != nil {
+			zap.S().Errorf("failed to write dataflow graph: %s", err.Error())
+		}
+	}()
+	go func() {
+		defer wg.Done()
+		err := construct.GraphToSVG(sol.DeploymentGraph(), "iac")
+		if err != nil {
+			zap.S().Errorf("failed to write iac graph: %s", err.Error())
+		}
+	}()
+	wg.Wait()
+}