wip: implement protoc-gen-prost-validate

Signed-off-by: Adphi <[email protected]>

example/build-with-buf/Cargo.toml

@@ -19,5 +19,6 @@ pbjson = "0.7"
 pbjson-types = "0.7"
 serde = "1.0"
 tonic = { version = "0.12", features = ["gzip"] }
+prost-validate = { path = "../../../prost-validate" }
 
 [workspace]

example/build-with-buf/buf.gen.yaml

@@ -1,27 +1,36 @@
 version: v1
 plugins:
   - plugin: prost
-    #path: ../../target/debug/protoc-gen-prost
+    # path: ../../target/debug/protoc-gen-prost
     out: src/gen
     opt:
-#      - bytes=.
-      - compile_well_known_types
-      - extern_path=.google.protobuf=::pbjson_types
+    # - bytes=.
+    # - compile_well_known_types
+    # - extern_path=.google.protobuf=::pbjson_types
       - file_descriptor_set
       - enable_type_names
   - plugin: prost-serde
-    #path: ../../target/debug/protoc-gen-prost-serde
+    path: ../../target/debug/protoc-gen-prost-serde
     out: src/gen
   - plugin: tonic
-    #path: ../../target/debug/protoc-gen-tonic
+    # path: ../../target/debug/protoc-gen-tonic
     out: src/gen
     opt:
       - compile_well_known_types
-      - extern_path=.google.protobuf=::pbjson_types
+    # - extern_path=.google.protobuf=::pbjson_types
   - plugin: prost-crate
-    #path: ../../target/debug/protoc-gen-prost-crate
+    # path: ../../target/debug/protoc-gen-prost-crate
     out: .
     strategy: all
     opt:
       - include_file=src/gen/mod.rs
       - gen_crate
+  - plugin: prost-validate
+    # path: ../../target/debug/protoc-gen-prost-validate
+    out: src/gen
+    strategy: all
+    opt:
+    # - bytes=.
+    # - compile_well_known_types
+    # - extern_path=.google.protobuf=::pbjson_types
+      - enable_type_names

example/build-with-buf/proto/buf.lock

@@ -0,0 +1,8 @@
+# Generated by buf. DO NOT EDIT.
+version: v1
+deps:
+  - remote: buf.build
+    owner: envoyproxy
+    repository: protoc-gen-validate
+    commit: daf171c6cdb54629b5f51e345a79e4dd
+    digest: shake256:4ae167d7eed10da5f83a3f5df8c670d249170f11b1f2fd19afda06be2cff4d47dcc95e9e4a15151ecc8ce2d3d3614caf9a04d3ad82fb768a3870dedfa9455f36

example/build-with-buf/proto/buf.yaml

@@ -1 +1,3 @@
 version: v1
+deps:
+- buf.build/envoyproxy/protoc-gen-validate

example/build-with-buf/proto/example/ExampleRequest.proto

@@ -2,6 +2,8 @@ syntax = "proto3";
 
 package example;
 
+import "validate/validate.proto";
+
 message ExampleRequest {
-    string example = 1;
+    string example = 1 [(validate.rules).string = {min_len: 1, max_len: 10}];
 }

protoc-gen-prost-validate/Cargo.toml

@@ -1,11 +1,22 @@
 [package]
 name = "protoc-gen-prost-validate"
 version = "0.0.1"
-authors = ["Marcus Griep <[email protected]>"]
+authors = ["Marcus Griep <[email protected]>", "Adphi <[email protected]>"]
 description = "Coming soon…"
 license = "Apache-2.0"
 edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+prost-build.workspace = true
+prost-types.workspace = true
+prost.workspace = true
+protoc-gen-prost = { version = "0.4.0", path = "../protoc-gen-prost" }
+prost-validate-build = { version = "0.2.1" }
+prost-validate-derive-core = { version = "0.2.1" }
+prost-validate-types = { version = "0.2.1" }
+syn = "2.0.75"
+proc-macro2 = "1.0.86"
+prost-reflect = "0.14.2"
+prettyplease = "0.2.9"

protoc-gen-prost-validate/src/generator.rs

@@ -0,0 +1,166 @@
+use proc_macro2::TokenStream;
+use prost::Message;
+use prost_build::Module;
+use prost_reflect::DescriptorPool;
+use prost_types::compiler::code_generator_response::File;
+use prost_validate_build::Builder;
+use protoc_gen_prost::{Error, Generator, ModuleRequest, ModuleRequestSet, Result};
+use std::collections::HashMap;
+use syn::__private::ToTokens;
+
+pub struct ProstValidateGenerator {
+    builder: Builder,
+    config: prost_build::Config,
+    insert_include: bool,
+}
+
+impl Generator for ProstValidateGenerator {
+    fn generate(&mut self, module_request_set: &ModuleRequestSet) -> Result {
+        let file_contents = self.generate_prost(module_request_set)?;
+        Ok(module_request_set
+            .requests()
+            .filter_map(|(module, request)| {
+                self.generate_one(module, request, &file_contents)
+                    .transpose()
+            })
+            .collect::<std::result::Result<Vec<_>, Error>>()?
+            .iter()
+            .flatten()
+            .cloned()
+            .collect())
+    }
+}
+
+impl ProstValidateGenerator {
+    pub fn new(config: prost_build::Config, insert_include: bool) -> Self {
+        Self {
+            builder: Builder::new(),
+            config,
+            insert_include,
+        }
+    }
+
+    fn generate_prost(
+        &mut self,
+        module_request_set: &ModuleRequestSet,
+    ) -> std::result::Result<HashMap<Module, String>, Error> {
+        // we need to generate a raw file descriptor set in order to build prost-reflect the descriptor pool
+        // otherwise we can't annotate the config due to missing options in the prost crates.
+        let file_descriptor_set_bytes = RawProtosSet {
+            file: module_request_set
+                .requests()
+                .map(|(_, request)| request.raw_files())
+                .flatten()
+                .map(|f| f.to_vec())
+                .collect::<Vec<_>>(),
+        }
+        .encode_to_vec();
+        let pool = DescriptorPool::decode(file_descriptor_set_bytes.as_slice())?;
+
+        self.builder.annotate(&mut self.config, &pool);
+        let prost_requests: Vec<_> = module_request_set
+            .requests()
+            .flat_map(|(module, request)| {
+                request.files().map(|proto| (module.clone(), proto.clone()))
+            })
+            .collect();
+
+        Ok(self.config.generate(prost_requests)?)
+    }
+
+    fn generate_one(
+        &mut self,
+        module: &Module,
+        request: &ModuleRequest,
+        file_contents: &HashMap<Module, String>,
+    ) -> std::result::Result<Option<Vec<File>>, Error> {
+        let content = match file_contents.get(module) {
+            Some(content) => content,
+            None => return Ok(None),
+        };
+        let output_filename = format!("{}.validate.rs", request.proto_package_name());
+
+        let mut file_stream = TokenStream::new();
+        syn::parse_file(content)
+            .expect("failed to parse generated file")
+            .items
+            .iter()
+            .filter_map(filter_item)
+            .map(|stream| prost_validate_derive_core::derive(stream))
+            .for_each(|stream| stream.to_tokens(&mut file_stream));
+
+        if file_stream.is_empty() {
+            return Ok(None);
+        }
+
+        let mut res = Vec::with_capacity(2);
+        if self.insert_include {
+            // only include file if it is part of the proto generation request
+            res.push(
+                match request.append_to_file(|buf| {
+                    buf.push_str("include!(\"");
+                    buf.push_str(&output_filename);
+                    buf.push_str("\");\n");
+                }) {
+                    Some(file) => file,
+                    None => return Ok(None),
+                },
+            );
+        }
+
+        let file = syn::parse_file(file_stream.to_string().as_str())?;
+        let content = format!(
+            "// @generated by protoc-gen-prost-validate\n{}",
+            prettyplease::unparse(&file).as_str()
+        );
+        res.push(File {
+            name: Some(output_filename.clone()),
+            content: Some(content),
+            ..File::default()
+        });
+        Ok(Some(res))
+    }
+}
+
+fn filter_item(item: &syn::Item) -> Option<TokenStream> {
+    match item {
+        syn::Item::Struct(s) => {
+            if has_validator_derive(&s.attrs) {
+                Some(item.to_token_stream())
+            } else {
+                None
+            }
+        }
+        syn::Item::Enum(e) => {
+            if has_validator_derive(&e.attrs) {
+                Some(item.to_token_stream())
+            } else {
+                None
+            }
+        }
+        _ => None,
+    }
+}
+
+fn has_validator_derive(attrs: &Vec<syn::Attribute>) -> bool {
+    let mut has_validator = false;
+    for attr in attrs {
+        if attr.path().is_ident("derive") {
+            let _ = attr.parse_nested_meta(|meta| {
+                has_validator =
+                    meta.path.to_token_stream().to_string() == ":: prost_validate :: Validator";
+                Ok(())
+            });
+        }
+        if has_validator {
+            return true;
+        }
+    }
+    false
+}
+
+#[derive(Clone, PartialEq, ::prost::Message)]
+struct RawProtosSet {
+    #[prost(bytes = "vec", repeated, tag = "1")]
+    pub file: Vec<Vec<u8>>,
+}

protoc-gen-prost-validate/src/lib.rs

@@ -0,0 +1,63 @@
+mod generator;
+
+use crate::generator::ProstValidateGenerator;
+use prost::Message;
+use prost_types::compiler::CodeGeneratorRequest;
+use protoc_gen_prost::{
+    Generator, InvalidParameter, ModuleRequestSet, Param, Params, ProstParameters,
+};
+use std::str::FromStr;
+
+/// Parameters use to configure [`Generator`]s built into `protoc-gen-prost-validate`
+///
+/// [`Generator`]: crate::Generator
+#[derive(Debug, Default)]
+pub struct Parameters {
+    /// Prost parameters, used to generate [`prost_build::Config`]
+    pub prost: ProstParameters,
+
+    /// Whether to include the `include!` directive in the prost generated file
+    pub no_include: bool,
+}
+
+impl FromStr for Parameters {
+    type Err = InvalidParameter;
+    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
+        let mut ret_val = Self::default();
+        for param in Params::from_protoc_plugin_opts(s)? {
+            if let Err(param) = ret_val.prost.try_handle_parameter(param) {
+                match param {
+                    Param::Parameter {
+                        param: "no_include",
+                    }
+                    | Param::Value {
+                        param: "no_include",
+                        value: "true",
+                    } => ret_val.no_include = true,
+                    Param::Value {
+                        param: "no_include",
+                        value: "false",
+                    } => (),
+                    _ => return Err(InvalidParameter::from(param)),
+                }
+            }
+        }
+
+        Ok(ret_val)
+    }
+}
+
+/// Execute the core _Prost!_ generator from a raw [`CodeGeneratorRequest`]
+pub fn execute(raw_request: &[u8]) -> protoc_gen_prost::Result {
+    let request = CodeGeneratorRequest::decode(raw_request)?;
+    let params = request.parameter().parse::<Parameters>()?;
+    let module_request_set = ModuleRequestSet::new(
+        request.file_to_generate,
+        request.proto_file,
+        raw_request,
+        params.prost.default_package_filename(),
+    )?;
+    let files = ProstValidateGenerator::new(params.prost.to_prost_config(), !params.no_include)
+        .generate(&module_request_set)?;
+    Ok(files)
+}

protoc-gen-prost-validate/src/main.rs

@@ -1,3 +1,26 @@
-fn main() {
-    println!("Hello, world!");
+use std::{
+    env,
+    io::{self, Read, Write},
+    process::exit,
+};
+
+use prost::Message;
+use protoc_gen_prost::GeneratorResultExt;
+
+fn main() -> io::Result<()> {
+    if env::args().any(|x| x == "--version") {
+        println!(env!("CARGO_PKG_VERSION"));
+        exit(0);
+    }
+
+    let mut buf = Vec::new();
+    io::stdin().read_to_end(&mut buf)?;
+
+    let response = protoc_gen_prost_validate::execute(buf.as_slice()).unwrap_codegen_response();
+
+    buf.clear();
+    response.encode(&mut buf).expect("error encoding response");
+    io::stdout().write_all(&buf)?;
+
+    Ok(())
 }