refactor(context): Implement more explicit merging of variables

The hierarchy for loading variables was previously not expressed
explicitly.

This commit refactors the logic for merging variables to explicitly
set the different layers of variables as values on the context object
and merge them for each resource set in `mergeContextValues`.

1 files changed, 37 insertions, 23 deletions

diff --git a/context/context_test.go b/context/context_test.go
index 6dc27466a579..6a4cec6c9383 100644
--- a/context/context_test.go
+++ b/context/context_test.go
@@ -14,8 +14,10 @@ import (
 	"testing"
 )
 
+var noExplicitVars []string = make([]string, 0)
+
 func TestLoadFlatContextFromFile(t *testing.T) {
-	ctx, err := LoadContextFromFile("testdata/flat-test.yaml")
+	ctx, err := LoadContext("testdata/flat-test.yaml", &noExplicitVars)
 
 	if err != nil {
 		t.Error(err)
@@ -35,12 +37,15 @@ func TestLoadFlatContextFromFile(t *testing.T) {
 					"apiPort":          float64(4567), // yep!
 					"importantFeature": true,
 					"version":          "1.0-0e6884d",
+					"globalVar":        "lizards",
 				},
 				Include: nil,
 				Parent:  "",
 			},
 		},
 		BaseDir: "testdata",
+		ImportedVars: make(map[string]interface{}, 0),
+		ExplicitVars: make(map[string]interface{}, 0),
 	}
 
 	if !reflect.DeepEqual(*ctx, expected) {
@@ -50,7 +55,7 @@ func TestLoadFlatContextFromFile(t *testing.T) {
 }
 
 func TestLoadContextWithResourceSetCollections(t *testing.T) {
-	ctx, err := LoadContextFromFile("testdata/collections-test.yaml")
+	ctx, err := LoadContext("testdata/collections-test.yaml", &noExplicitVars)
 
 	if err != nil {
 		t.Error(err)
@@ -70,6 +75,7 @@ func TestLoadContextWithResourceSetCollections(t *testing.T) {
 					"apiPort":          float64(4567), // yep!
 					"importantFeature": true,
 					"version":          "1.0-0e6884d",
+					"globalVar":        "lizards",
 				},
 				Include: nil,
 				Parent:  "",
@@ -79,12 +85,15 @@ func TestLoadContextWithResourceSetCollections(t *testing.T) {
 				Path: "collection/nested",
 				Values: map[string]interface{}{
 					"lizards": "good",
+					"globalVar": "lizards",
 				},
 				Include: nil,
 				Parent:  "collection",
 			},
 		},
 		BaseDir: "testdata",
+		ImportedVars: make(map[string]interface{}, 0),
+		ExplicitVars: make(map[string]interface{}, 0),
 	}
 
 	if !reflect.DeepEqual(*ctx, expected) {
@@ -95,7 +104,7 @@ func TestLoadContextWithResourceSetCollections(t *testing.T) {
 }
 
 func TestSubresourceVariableInheritance(t *testing.T) {
-	ctx, err := LoadContextFromFile("testdata/parent-variables.yaml")
+	ctx, err := LoadContext("testdata/parent-variables.yaml", &noExplicitVars)
 
 	if err != nil {
 		t.Error(err)
@@ -117,6 +126,8 @@ func TestSubresourceVariableInheritance(t *testing.T) {
 			},
 		},
 		BaseDir: "testdata",
+		ImportedVars: make(map[string]interface{}, 0),
+		ExplicitVars: make(map[string]interface{}, 0),
 	}
 
 	if !reflect.DeepEqual(*ctx, expected) {
@@ -126,7 +137,7 @@ func TestSubresourceVariableInheritance(t *testing.T) {
 }
 
 func TestSubresourceVariableInheritanceOverride(t *testing.T) {
-	ctx, err := LoadContextFromFile("testdata/parent-variable-override.yaml")
+	ctx, err := LoadContext("testdata/parent-variable-override.yaml", &noExplicitVars)
 
 	if err != nil {
 		t.Error(err)
@@ -147,6 +158,8 @@ func TestSubresourceVariableInheritanceOverride(t *testing.T) {
 			},
 		},
 		BaseDir: "testdata",
+		ImportedVars: make(map[string]interface{}, 0),
+		ExplicitVars: make(map[string]interface{}, 0),
 	}
 
 	if !reflect.DeepEqual(*ctx, expected) {
@@ -156,7 +169,7 @@ func TestSubresourceVariableInheritanceOverride(t *testing.T) {
 }
 
 func TestDefaultValuesLoading(t *testing.T) {
-	ctx, err := LoadContextFromFile("testdata/default-loading.yaml")
+	ctx, err := LoadContext("testdata/default-loading.yaml", &noExplicitVars)
 	if err != nil {
 		t.Error(err)
 		t.Fail()
@@ -175,7 +188,7 @@ func TestDefaultValuesLoading(t *testing.T) {
 }
 
 func TestImportValuesLoading(t *testing.T) {
-	ctx, err := LoadContextFromFile("testdata/import-vars-simple.yaml")
+	ctx, err := LoadContext("testdata/import-vars-simple.yaml", &noExplicitVars)
 	if err != nil {
 		t.Error(err)
 		t.Fail()
@@ -189,14 +202,14 @@ func TestImportValuesLoading(t *testing.T) {
 		},
 	}
 
-	if !reflect.DeepEqual(ctx.Global, expected) {
-		t.Error("Expected global values after loading imports did not match!")
+	if !reflect.DeepEqual(ctx.ImportedVars, expected) {
+		t.Error("Expected imported values after loading imports did not match!")
 		t.Fail()
 	}
 }
 
-func TestImportValuesOverride(t *testing.T) {
-	ctx, err := LoadContextFromFile("testdata/import-vars-override.yaml")
+func TestValuesOverride(t *testing.T) {
+	ctx, err := LoadContext("testdata/import-vars-override.yaml", &noExplicitVars)
 	if err != nil {
 		t.Error(err)
 		t.Fail()
@@ -208,18 +221,18 @@ func TestImportValuesOverride(t *testing.T) {
 			"artist": "Pallida",
 			"track":  "Tractor Beam",
 		},
-		"place":     "Oslo",
+		"place": "Oslo",
 		"globalVar": "very global!",
 	}
 
-	if !reflect.DeepEqual(ctx.Global, expected) {
-		t.Error("Expected global values after loading imports did not match!")
+	if !reflect.DeepEqual(ctx.ResourceSets[0].Values, expected) {
+		t.Error("Expected overrides after loading imports did not match!")
 		t.Fail()
 	}
 }
 
 func TestExplicitPathLoading(t *testing.T) {
-	ctx, err := LoadContextFromFile("testdata/explicit-path.yaml")
+	ctx, err := LoadContext("testdata/explicit-path.yaml", &noExplicitVars)
 	if err != nil {
 		t.Error(err)
 		t.Fail()
@@ -248,6 +261,8 @@ func TestExplicitPathLoading(t *testing.T) {
 			},
 		},
 		BaseDir: "testdata",
+		ImportedVars: make(map[string]interface{}, 0),
+		ExplicitVars: make(map[string]interface{}, 0),
 	}
 
 	if !reflect.DeepEqual(*ctx, expected) {
@@ -257,7 +272,7 @@ func TestExplicitPathLoading(t *testing.T) {
 }
 
 func TestExplicitSubresourcePathLoading(t *testing.T) {
-	ctx, err := LoadContextFromFile("testdata/explicit-subresource-path.yaml")
+	ctx, err := LoadContext("testdata/explicit-subresource-path.yaml", &noExplicitVars)
 	if err != nil {
 		t.Error(err)
 		t.Fail()
@@ -270,9 +285,12 @@ func TestExplicitSubresourcePathLoading(t *testing.T) {
 				Name:   "parent/child",
 				Path:   "parent-path/child-path",
 				Parent: "parent",
+				Values: make(map[string]interface{}, 0),
 			},
 		},
 		BaseDir: "testdata",
+		ImportedVars: make(map[string]interface{}, 0),
+		ExplicitVars: make(map[string]interface{}, 0),
 	}
 
 	if !reflect.DeepEqual(*ctx, expected) {
@@ -283,22 +301,18 @@ func TestExplicitSubresourcePathLoading(t *testing.T) {
 
 func TestSetVariablesFromArguments(t *testing.T) {
 	vars := []string{"version=some-service-version"}
-	ctx, _ := LoadContextFromFile("testdata/default-loading.yaml")
-
-	if err := ctx.SetVariablesFromArguments(&vars); err != nil {
-		t.Error(err)
-	}
+	ctx, _ := LoadContext("testdata/default-loading.yaml", &vars)
 
-	if version := ctx.Global["version"]; version != "some-service-version" {
+	if version := ctx.ExplicitVars["version"]; version != "some-service-version" {
 		t.Errorf(`Expected variable "version" to have value "some-service-version" but was "%s"`, version)
 	}
 }
 
 func TestSetInvalidVariablesFromArguments(t *testing.T) {
 	vars := []string{"version: some-service-version"}
-	ctx, _ := LoadContextFromFile("testdata/default-loading.yaml")
+	_, err := LoadContext("testdata/default-loading.yaml", &vars)
 
-	if err := ctx.SetVariablesFromArguments(&vars); err == nil {
+	if err == nil {
 		t.Error("Expected invalid variable to return an error")
 	}
 }