Modify resolution of global variables to avoid errors on plain strings

pkg/config/config.go

@@ -454,12 +454,10 @@ func ConvertMapToCty(iMap map[string]interface{}) (map[string]cty.Value, error)
 
 // ResolveGlobalVariables given a map of strings to cty.Value types, will examine
 // all cty.Values that are of type cty.String. If they are literal global variables,
-// then they are replaces by the cty.Value of the corresponding entry in yc.Vars
-// the cty.Value types that are string literal global variables to their value
+// then they are replaced by the cty.Value of the corresponding entry in
+// yc.Vars. All other cty.Values are unmodified.
 // ERROR: if conversion from yc.Vars to map[string]cty.Value fails
-// ERROR: if (somehow) the cty.String cannot be covnerted to a Go string
-// ERROR: if there are literal variables which are not globals
-//        (this will be a use case we should consider)
+// ERROR: if (somehow) the cty.String cannot be converted to a Go string
 // ERROR: rely on HCL TraverseAbs to bubble up "diagnostics" when the global variable
 //        being resolved does not exist in yc.Vars
 func (yc *YamlConfig) ResolveGlobalVariables(ctyMap map[string]cty.Value) error {
@@ -477,7 +475,8 @@ func (yc *YamlConfig) ResolveGlobalVariables(ctyMap map[string]cty.Value) error
 				return err
 			}
 			ctx, varName, found := IdentifyLiteralVariable(valString)
-			// confirm literal and that it is global
+			// only attempt resolution on global literal variables
+			// leave all other strings alone (including non-global)
 			if found && ctx == "var" {
 				varTraversal := hcl.Traversal{
 					hcl.TraverseRoot{Name: ctx},
@@ -488,8 +487,6 @@ func (yc *YamlConfig) ResolveGlobalVariables(ctyMap map[string]cty.Value) error
 					return diags
 				}
 				ctyMap[key] = newVal
-			} else {
-				return fmt.Errorf("%s was not a literal global variable ((var.name))", valString)
 			}
 		}
 	}

pkg/config/config_test.go

@@ -505,49 +505,51 @@ func (s *MySuite) TestConvertMapToCty(c *C) {
 
 func (s *MySuite) TestResolveGlobalVariables(c *C) {
 	var err error
-	var testkey = "testkey"
+	var testkey1 = "testkey1"
+	var testkey2 = "testkey2"
+	var testkey3 = "testkey3"
 	bc := getBlueprintConfigForTest()
 	ctyMap := make(map[string]cty.Value)
 	err = bc.Config.ResolveGlobalVariables(ctyMap)
 	c.Assert(err, IsNil)
 
-	// confirm that a plain string (non-variable) is unchanged and errors
+	// confirm plain string is unchanged and does not error
 	testCtyString := cty.StringVal("testval")
-	ctyMap[testkey] = testCtyString
+	ctyMap[testkey1] = testCtyString
 	err = bc.Config.ResolveGlobalVariables(ctyMap)
-	c.Assert(err, NotNil)
-	c.Assert(ctyMap[testkey], Equals, testCtyString)
+	c.Assert(err, IsNil)
+	c.Assert(ctyMap[testkey1], Equals, testCtyString)
 
-	// confirm that a literal, but not global, variable is unchanged and errors
+	// confirm literal, non-global, variable is unchanged and does not error
 	testCtyString = cty.StringVal("((module.testval))")
-	ctyMap[testkey] = testCtyString
+	ctyMap[testkey1] = testCtyString
 	err = bc.Config.ResolveGlobalVariables(ctyMap)
-	c.Assert(err, NotNil)
-	c.Assert(ctyMap[testkey], Equals, testCtyString)
+	c.Assert(err, IsNil)
+	c.Assert(ctyMap[testkey1], Equals, testCtyString)
 
 	// confirm failed resolution of a literal global
 	testCtyString = cty.StringVal("((var.test_global_var))")
-	ctyMap[testkey] = testCtyString
+	ctyMap[testkey1] = testCtyString
 	err = bc.Config.ResolveGlobalVariables(ctyMap)
+	c.Assert(err, NotNil)
 	c.Assert(err.Error(), Matches, ".*Unsupported attribute;.*")
 
-	// confirm successful resolution a literal global string
-	testGlobalVar := "test_global_var"
-	testGlobalVarString := "testval"
-	bc.Config.Vars[testGlobalVar] = testGlobalVarString
-	testCtyString = cty.StringVal(fmt.Sprintf("((var.%s))", testGlobalVar))
-	ctyMap[testkey] = testCtyString
-	err = bc.Config.ResolveGlobalVariables(ctyMap)
-	c.Assert(err, IsNil)
-	c.Assert(ctyMap[testkey], Equals, cty.StringVal(testGlobalVarString))
-
-	// confirm successful resolution a literal global boolean
-	testGlobalVar = "test_global_var"
-	testGlobalVarBool := true
-	bc.Config.Vars[testGlobalVar] = testGlobalVarBool
-	testCtyString = cty.StringVal(fmt.Sprintf("((var.%s))", testGlobalVar))
-	ctyMap[testkey] = testCtyString
+	// confirm successful resolution of literal globals in presence of other strings
+	testGlobalVarString := "test_global_string"
+	testGlobalValString := "testval"
+	testGlobalVarBool := "test_global_bool"
+	testGlobalValBool := "testval"
+	testPlainString := "plain-string"
+	bc.Config.Vars[testGlobalVarString] = testGlobalValString
+	bc.Config.Vars[testGlobalVarBool] = testGlobalValBool
+	testCtyString = cty.StringVal(fmt.Sprintf("((var.%s))", testGlobalVarString))
+	testCtyBool := cty.StringVal(fmt.Sprintf("((var.%s))", testGlobalVarBool))
+	ctyMap[testkey1] = testCtyString
+	ctyMap[testkey2] = testCtyBool
+	ctyMap[testkey3] = cty.StringVal(testPlainString)
 	err = bc.Config.ResolveGlobalVariables(ctyMap)
 	c.Assert(err, IsNil)
-	c.Assert(ctyMap[testkey], Equals, cty.BoolVal(testGlobalVarBool))
+	c.Assert(ctyMap[testkey1], Equals, cty.StringVal(testGlobalValString))
+	c.Assert(ctyMap[testkey2], Equals, cty.StringVal(testGlobalValBool))
+	c.Assert(ctyMap[testkey3], Equals, cty.StringVal(testPlainString))
 }

pkg/reswriter/packerwriter.go

@@ -61,7 +61,10 @@ func (w PackerWriter) writeResourceLevel(yamlConfig *config.YamlConfig, bpDirect
 				return fmt.Errorf(
 					"error converting global vars to cty for writing: %v", err)
 			}
-			yamlConfig.ResolveGlobalVariables(ctySettings)
+			err = yamlConfig.ResolveGlobalVariables(ctySettings)
+			if err != nil {
+				return err
+			}
 			resPath := filepath.Join(groupPath, res.ID)
 			err = writePackerAutovars(ctySettings, resPath)
 			if err != nil {

tools/validate_configs/validate_configs.sh

@@ -50,6 +50,10 @@ run_test() {
 	}
 	for folder in ./*; do
 		cd "$folder"
+		pkrdirs=()
+		while IFS= read -r -d $'\n'; do
+			pkrdirs+=("$REPLY")
+		done < <(find . -name "*.pkr.hcl" -printf '%h\n' | sort -u)
 		if [ -f 'main.tf' ]; then
 			tfpw=$(pwd)
 			terraform init -no-color -backend=false >"${exampleFile}.init" ||
@@ -62,8 +66,16 @@ run_test() {
 					echo "*** ERROR: terraform validate failed for ${example}, logs in ${tfpw}"
 					exit 1
 				}
+		elif [ ${#pkrdirs[@]} -gt 0 ]; then
+			for pkrdir in "${pkrdirs[@]}"; do
+				packer validate -syntax-only "${pkrdir}" >/dev/null ||
+					{
+						echo "*** ERROR: packer validate failed for ${example}"
+						exit 1
+					}
+			done
 		else
-			echo "terraform not found in folder ${BLUEPRINT}/${folder}. Skipping."
+			echo "neither packer nor terraform found in folder ${BLUEPRINT}/${folder}. Skipping."
 		fi
 		cd .. # back to blueprint folder
 	done