internal/config: walk the graph and merge configuration

internal/config/config.go

@@ -91,14 +91,7 @@ func Parse(path string) (Config, error) {
 	if err != nil {
 		return Config{}, fmt.Errorf("build dag: %w", err)
 	}
-	if err = graph.Resolve(); err != nil {
-		return Config{}, fmt.Errorf("resolve dag: %w", err)
-	}
-
-	cfg, err := graph.Config(path)
-	if err != nil {
-		return Config{}, fmt.Errorf("unknown configuration: %w", err)
-	}
+	cfg := graph.Resolve()
 
 	if err = cfg.validate(); err != nil {
 		return Config{}, fmt.Errorf("validate config: %w", err)

internal/config/configgraph.go

@@ -76,16 +76,33 @@ func discoverConfig(url, parent string, d *dag.DAG, configs map[string]Config) e
 	return nil
 }
 
-// Resolve walks the dag and merge the configuration.
-func (d *ConfigGraph) Resolve() error {
-	// TODO: Walk the dag and merge configurations.
-	return nil
-}
-
 // Config returns a configuration for the given URL.
-func (d *ConfigGraph) Config(url string) (Config, error) {
-	if cfg, ok := d.configs[url]; ok {
+func (cg *ConfigGraph) Config(url string) (Config, error) {
+	if cfg, ok := cg.configs[url]; ok {
 		return cfg, nil
 	}
 	return Config{}, fmt.Errorf("could not find config for %s", url)
 }
+
+// Resolve walks the dag and merge the configuration.
+func (cg *ConfigGraph) Resolve() Config {
+	var cfg *Config
+	cg.dag.DFSWalk(func(vertexID string, vertex interface{}) {
+		vexCfg, err := cg.Config(vertex.(string))
+		if err != nil {
+			panic(err)
+		}
+
+		if cfg == nil {
+			cfg = &vexCfg
+			return
+		}
+
+		vexCfg, err = merge(vexCfg, *cfg)
+		if err != nil {
+			panic(err)
+		}
+		cfg = &vexCfg
+	})
+	return *cfg
+}

internal/config/configgraph_test.go

@@ -27,7 +27,7 @@ func TestNewConfigGraph(t *testing.T) {
 					"testdata/include/no_includes.yaml": {
 						LavaVersion: ptr("v1.0.0"),
 						ChecktypeURLs: []string{
-							"checktypes.json",
+							"checktypes_no_includes.json",
 						},
 						Targets: []Target{
 							{
@@ -61,7 +61,7 @@ func TestNewConfigGraph(t *testing.T) {
 					"testdata/include/no_includes.yaml": {
 						LavaVersion: ptr("v1.0.0"),
 						ChecktypeURLs: []string{
-							"checktypes.json",
+							"checktypes_no_includes.json",
 						},
 						Targets: []Target{
 							{
@@ -103,7 +103,7 @@ func TestNewConfigGraph(t *testing.T) {
 					"testdata/include/no_includes.yaml": {
 						LavaVersion: ptr("v1.0.0"),
 						ChecktypeURLs: []string{
-							"checktypes.json",
+							"checktypes_no_includes.json",
 						},
 						Targets: []Target{
 							{
@@ -136,6 +136,9 @@ func TestNewConfigGraph(t *testing.T) {
 								AssetType:  types.DomainName,
 							},
 						},
+						ReportConfig: ReportConfig{
+							Severity: ptr(SeverityCritical),
+						},
 					},
 					"testdata/include/common_a.yaml": {
 						Includes:    []string{"testdata/include/no_includes.yaml"},
@@ -149,6 +152,9 @@ func TestNewConfigGraph(t *testing.T) {
 								AssetType:  types.DomainName,
 							},
 						},
+						ReportConfig: ReportConfig{
+							Severity: ptr(SeverityMedium),
+						},
 					},
 					"testdata/include/common_b.yaml": {
 						Includes:    []string{"testdata/include/no_includes.yaml"},
@@ -166,7 +172,7 @@ func TestNewConfigGraph(t *testing.T) {
 					"testdata/include/no_includes.yaml": {
 						LavaVersion: ptr("v1.0.0"),
 						ChecktypeURLs: []string{
-							"checktypes.json",
+							"checktypes_no_includes.json",
 						},
 						Targets: []Target{
 							{
@@ -196,3 +202,135 @@ func TestNewConfigGraph(t *testing.T) {
 		})
 	}
 }
+
+func TestConfigGraph_Resolve(t *testing.T) {
+	tests := []struct {
+		name    string
+		URL     string
+		want    Config
+		wantErr bool
+	}{
+		{
+			name: "no includes",
+			URL:  "testdata/include/no_includes.yaml",
+			want: Config{
+				LavaVersion: ptr("v1.0.0"),
+				ChecktypeURLs: []string{
+					"checktypes_no_includes.json",
+				},
+				Targets: []Target{
+					{
+						Identifier: "example.com",
+						AssetType:  types.DomainName,
+					},
+				},
+			},
+			wantErr: false,
+		},
+		{
+			name: "local file",
+			URL:  "testdata/include/local.yaml",
+			want: Config{
+				Includes:    []string{"testdata/include/no_includes.yaml"},
+				LavaVersion: ptr("v1.0.0"),
+				ChecktypeURLs: []string{
+					"checktypes_no_includes.json",
+					"checktypes.json",
+				},
+				Targets: []Target{
+					{
+						Identifier: "example.com",
+						AssetType:  types.DomainName,
+					},
+					{
+						Identifier: "example.com",
+						AssetType:  types.DomainName,
+					},
+				},
+			},
+			wantErr: false,
+		},
+		{
+			name: "duplicated",
+			URL:  "testdata/include/duplicated.yaml",
+			want: Config{
+				Includes: []string{
+					"testdata/include/no_includes.yaml",
+					"testdata/include/no_includes.yaml",
+				},
+				LavaVersion: ptr("v1.0.0"),
+				ChecktypeURLs: []string{
+					"checktypes_no_includes.json",
+					"checktypes.json",
+				},
+				Targets: []Target{
+					{
+						Identifier: "example.com",
+						AssetType:  types.DomainName,
+					},
+					{
+						Identifier: "example.com",
+						AssetType:  types.DomainName,
+					},
+				},
+			},
+			wantErr: false,
+		},
+		{
+			name: "common includes",
+			URL:  "testdata/include/common.yaml",
+			want: Config{
+				Includes: []string{
+					"testdata/include/no_includes.yaml",
+					"testdata/include/no_includes.yaml",
+					"testdata/include/common_a.yaml",
+					"testdata/include/common_b.yaml",
+				},
+				LavaVersion: ptr("v1.0.0"),
+				ChecktypeURLs: []string{
+					"checktypes.json",
+					"checktypes_no_includes.json",
+					"checktypes.json",
+					"checktypes.json",
+				},
+				Targets: []Target{
+					{
+						Identifier: "example.com",
+						AssetType:  types.DomainName,
+					},
+					{
+						Identifier: "example.com",
+						AssetType:  types.DomainName,
+					},
+					{
+						Identifier: "example.com",
+						AssetType:  types.DomainName,
+					},
+					{
+						Identifier: "example.com",
+						AssetType:  types.DomainName,
+					},
+				},
+				ReportConfig: ReportConfig{
+					Severity: ptr(SeverityCritical),
+				},
+			},
+			wantErr: false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			graph, err := NewConfigGraph(tt.URL)
+			if err != nil {
+				t.Errorf("build dag: %v", err)
+			}
+			got := graph.Resolve()
+			if (err != nil) != tt.wantErr {
+				t.Errorf("unexpected error: %v", err)
+			}
+			if diff := cmp.Diff(tt.want, got); diff != "" {
+				t.Errorf("configs mismatch (-want +got):\n%v", diff)
+			}
+		})
+	}
+}

internal/config/dag/dag.go

@@ -94,3 +94,17 @@ func (d *DAG) getVertexID(s string) string {
 	}
 	return ""
 }
+
+// WalkFunc represents a function that implements the [hdag.Visitor]
+// interface.
+type WalkFunc func(vertexID string, vertex interface{})
+
+// Visit is required by the [hdag.Visitor] interface.
+func (fn WalkFunc) Visit(v hdag.Vertexer) {
+	fn(v.Vertex())
+}
+
+// DFSWalk walks the [DAG] using a depth first strategy.
+func (d *DAG) DFSWalk(fn WalkFunc) {
+	d.dag.DFSWalk(fn)
+}

internal/config/testdata/include/common.yaml

@@ -7,3 +7,5 @@ checktypes:
 targets:
   - identifier: example.com
     type: DomainName
+report:
+  severity: critical

internal/config/testdata/include/common_a.yaml

@@ -6,3 +6,5 @@ checktypes:
 targets:
   - identifier: example.com
     type: DomainName
+report:
+  severity: medium

internal/config/testdata/include/no_includes.yaml

@@ -1,6 +1,6 @@
 lava: v1.0.0
 checktypes:
-  - checktypes.json
+  - checktypes_no_includes.json
 targets:
   - identifier: example.com
     type: DomainName