diff --git a/docs/interoperability.md b/docs/interoperability.md index 3847e22..8d45050 100644 --- a/docs/interoperability.md +++ b/docs/interoperability.md @@ -4,9 +4,9 @@ - [Using Scripts](#using-scripts) - [Type Conversion Table](#type-conversion-table) -- [Compiler and VM](#compiler-and-vm) - [User Types](#user-types) - [Sandbox Environments](#sandbox-environments) +- [Compiler and VM](#compiler-and-vm) ## Using Scripts @@ -102,15 +102,52 @@ When adding a Variable _([Script.Add](https://godoc.org/github.com/d5/tengo/scri One can easily add and use customized value types in Tengo code by implementing [Object](https://godoc.org/github.com/d5/tengo/objects#Object) interface. Tengo runtime will treat the user types exactly in the same way it does to the runtime types with no performance overhead. See [Tengo Objects](https://github.com/d5/tengo/blob/master/docs/objects.md) for more details. +## Sandbox Environments + +To securely compile and execute _potentially_ unsafe script code, you can use the following Script functions. + +#### Script.DisableBuiltinFunction(name string) + +DisableBuiltinFunction disables and removes a builtin function from the compiler. Compiler will reports a compile-time error if the given name is referenced. + +```golang +s := script.New([]byte(`print([1, 2, 3])`)) + +s.DisableBuiltinFunction("print") + +_, err := s.Run() // compile error +``` + +#### Script.DisableStdModule(name string) + +DisableStdModule disables a [standard library](https://github.com/d5/tengo/blob/master/docs/stdlib.md) module. Compile will report a compile-time error if the code tries to import the module with the given name. + +```golang +s := script.New([]byte(`import("exec")`)) + +s.DisableStdModule("exec") + +_, err := s.Run() // compile error +``` + +#### Script.SetUserModuleLoader(loader compiler.ModuleLoader) + +SetUserModuleLoader replaces the default user-module loader of the compiler, which tries to read the source from a local file. + +```golang +s := script.New([]byte(`math := import("mod1"); a := math.foo()`)) + +s.SetUserModuleLoader(func(moduleName string) ([]byte, error) { + if moduleName == "mod1" { + return []byte(`foo := func() { return 5 }`), nil + } + + return nil, errors.New("module not found") +}) +``` + ## Compiler and VM Although it's not recommended, you can directly create and run the Tengo [Parser](https://godoc.org/github.com/d5/tengo/compiler/parser#Parser), [Compiler](https://godoc.org/github.com/d5/tengo/compiler#Compiler), and [VM](https://godoc.org/github.com/d5/tengo/runtime#VM) for yourself instead of using Scripts and Script Variables. It's a bit more involved as you have to manage the symbol tables and global variables between them, but, basically that's what Script and Script Variable is doing internally. _TODO: add more information here_ - -## Sandbox Environments - -In an environment where a _(potentially)_ unsafe script code needs to be executed, - -_TODO: add more information here_ -