Added filebase64sha256 support for NodeJS

pkg/codegen/nodejs/gen_program.go

@@ -53,6 +53,9 @@ func GenerateProgram(program *pcl.Program) (map[string][]byte, hcl.Diagnostics,
 	}
 	g.Formatter = format.NewFormatter(g)
 
+	// Creating a list to store and later print helper methods if they turn out to be needed
+	preambleHelperMethods := codegen.NewStringSet()
+
 	for _, p := range program.Packages() {
 		if err := p.ImportLanguages(map[string]schema.Language{"nodejs": Importer}); err != nil {
 			return nil, nil, err
@@ -60,7 +63,7 @@ func GenerateProgram(program *pcl.Program) (map[string][]byte, hcl.Diagnostics,
 	}
 
 	var index bytes.Buffer
-	g.genPreamble(&index, program)
+	g.genPreamble(&index, program, preambleHelperMethods)
 	for _, n := range nodes {
 		if r, ok := n.(*pcl.Resource); ok && requiresAsyncMain(r) {
 			g.asyncMain = true
@@ -150,7 +153,7 @@ func (g *generator) genComment(w io.Writer, comment syntax.Comment) {
 	}
 }
 
-func (g *generator) genPreamble(w io.Writer, program *pcl.Program) {
+func (g *generator) genPreamble(w io.Writer, program *pcl.Program, preambleHelperMethods codegen.StringSet) {
 	// Print the @pulumi/pulumi import at the top.
 	g.Fprintln(w, `import * as pulumi from "@pulumi/pulumi";`)
 
@@ -164,8 +167,13 @@ func (g *generator) genPreamble(w io.Writer, program *pcl.Program) {
 		}
 		diags := n.VisitExpressions(nil, func(n model.Expression) (model.Expression, hcl.Diagnostics) {
 			if call, ok := n.(*model.FunctionCallExpression); ok {
-				if i := g.getFunctionImports(call); i != "" {
-					importSet.Add(i)
+				if i := g.getFunctionImports(call); i[0] != "" {
+					for _, importPackage := range i {
+						importSet.Add(importPackage)
+					}
+				}
+				if helperMethodBody, ok := getHelperMethodIfNeeded(call.Name); ok {
+					preambleHelperMethods.Add(helperMethodBody)
 				}
 			}
 			return n, nil
@@ -192,6 +200,11 @@ func (g *generator) genPreamble(w io.Writer, program *pcl.Program) {
 		g.Fprintln(w, i)
 	}
 	g.Fprint(w, "\n")
+
+	// If we collected any helper methods that should be added, write them just before the main func
+	for _, preambleHelperMethodBody := range preambleHelperMethods.SortedValues() {
+		g.Fprintf(w, "%s\n\n", preambleHelperMethodBody)
+	}
 }
 
 func (g *generator) genNode(w io.Writer, n pcl.Node) {

pkg/codegen/nodejs/gen_program_expressions.go

@@ -266,24 +266,25 @@ func (g *generator) genRange(w io.Writer, call *model.FunctionCallExpression, en
 	genSuffix()
 }
 
-var functionImports = map[string]string{
-	intrinsicInterpolate: "@pulumi/pulumi",
-	"fileArchive":        "@pulumi/pulumi",
-	"fileAsset":          "@pulumi/pulumi",
-	"filebase64":         "fs",
-	"readFile":           "fs",
-	"readDir":            "fs",
-	"sha1":               "crypto",
+var functionImports = map[string][]string{
+	intrinsicInterpolate: []string{"@pulumi/pulumi"},
+	"fileArchive":        []string{"@pulumi/pulumi"},
+	"fileAsset":          []string{"@pulumi/pulumi"},
+	"filebase64":         []string{"fs"},
+	"filebase64sha256":   []string{"fs", "crypto"},
+	"readFile":           []string{"fs"},
+	"readDir":            []string{"fs"},
+	"sha1":               []string{"crypto"},
 }
 
-func (g *generator) getFunctionImports(x *model.FunctionCallExpression) string {
+func (g *generator) getFunctionImports(x *model.FunctionCallExpression) []string {
 	if x.Name != pcl.Invoke {
 		return functionImports[x.Name]
 	}
 
 	pkg, _, _, diags := functionName(x.Args[0])
 	contract.Assert(len(diags) == 0)
-	return "@pulumi/" + pkg
+	return []string{"@pulumi/" + pkg}
 }
 
 func (g *generator) GenFunctionCallExpression(w io.Writer, expr *model.FunctionCallExpression) {
@@ -322,6 +323,9 @@ func (g *generator) GenFunctionCallExpression(w io.Writer, expr *model.FunctionC
 		g.Fgenf(w, "new pulumi.asset.FileAsset(%.v)", expr.Args[0])
 	case "filebase64":
 		g.Fgenf(w, "Buffer.from(fs.readFileSync(%v), 'binary').toString('base64')", expr.Args[0])
+	case "filebase64sha256":
+		// Assuming the existence of the following helper method
+		g.Fgenf(w, "computeFilebase64sha256(%v)", expr.Args[0])
 	case pcl.Invoke:
 		pkg, module, fn, diags := functionName(expr.Args[0])
 		contract.Assert(len(diags) == 0)

pkg/codegen/nodejs/gen_program_utils.go

@@ -0,0 +1,17 @@
+package nodejs
+
+// Provides code for a method which will be placed in the program preamble if deemed
+// necessary. Because many tasks in Go such as reading a file require extensive error
+// handling, it is much prettier to encapsulate that error handling boilerplate as its
+// own function in the preamble.
+func getHelperMethodIfNeeded(functionName string) (string, bool) {
+	switch functionName {
+	case "filebase64sha256":
+		return `func computeFilebase64sha256(path string) string {
+	const fileData = Buffer.from(fs.readFileSync(path), 'binary')
+	return crypto.createHash('sha256').update(fileData).digest('hex')
+}`, true
+	default:
+		return "", false
+	}
+}