better parser generation

Cargo.lock

@@ -26,7 +26,6 @@ dependencies = [
 name = "amqp_codegen"
 version = "0.1.0"
 dependencies = [
- "anyhow",
  "heck",
  "itertools",
  "strong-xml",

amqp_codegen/Cargo.toml

@@ -6,7 +6,8 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-anyhow = "1.0.53"
 heck = "0.4.0"
 itertools = "0.10.3"
 strong-xml = "0.6.3"
+
+[features]

amqp_codegen/README.md

@@ -0,0 +1,3 @@
+codegen for method serialization/deserialization
+
+run using `cargo r > ../amqp_transport/src/classes/generated.rs`

amqp_codegen/src/main.rs

@@ -1,7 +1,6 @@
 mod parser;
 
 use crate::parser::codegen_parser;
-use anyhow::Result;
 use heck::ToUpperCamelCase;
 use std::fs;
 use strong_xml::XmlRead;
@@ -76,21 +75,21 @@ struct Field {
     asserts: Vec<Assert>,
 }
 
-fn main() -> Result<()> {
+fn main() {
     let content = fs::read_to_string("./amqp-0-9-1.xml").unwrap();
 
-    let amqp = Amqp::from_str(&content)?;
-    codegen(&amqp)
+    let amqp = Amqp::from_str(&content).unwrap();
+    codegen(&amqp);
 }
 
-fn codegen(amqp: &Amqp) -> Result<()> {
+fn codegen(amqp: &Amqp) {
     println!("// This file has been generated by `amqp_codegen`. Do not edit it manually.\n");
-    codegen_domain_defs(amqp)?;
-    codegen_class_defs(amqp)?;
-    codegen_parser(amqp)
+    codegen_domain_defs(amqp);
+    codegen_class_defs(amqp);
+    codegen_parser(amqp);
 }
 
-fn codegen_domain_defs(amqp: &Amqp) -> Result<()> {
+fn codegen_domain_defs(amqp: &Amqp) {
     for domain in &amqp.domains {
         let invariants = invariants(domain.asserts.iter());
 
@@ -103,11 +102,10 @@ fn codegen_domain_defs(amqp: &Amqp) -> Result<()> {
             amqp_type_to_rust_type(&domain.kind),
         );
     }
-
-    Ok(())
 }
 
-fn codegen_class_defs(amqp: &Amqp) -> Result<()> {
+fn codegen_class_defs(amqp: &Amqp) {
+    println!("#[derive(Debug, Clone, PartialEq)]");
     println!("pub enum Class {{");
     for class in &amqp.classes {
         let class_name = class.name.to_upper_camel_case();
@@ -118,6 +116,7 @@ fn codegen_class_defs(amqp: &Amqp) -> Result<()> {
     for class in &amqp.classes {
         let enum_name = class.name.to_upper_camel_case();
         println!("/// Index {}, handler = {}", class.index, class.handler);
+        println!("#[derive(Debug, Clone, PartialEq)]");
         println!("pub enum {enum_name} {{");
         for method in &class.methods {
             let method_name = method.name.to_upper_camel_case();
@@ -127,10 +126,8 @@ fn codegen_class_defs(amqp: &Amqp) -> Result<()> {
                 println!(" {{");
                 for field in &method.fields {
                     let field_name = snake_case(&field.name);
-                    let (field_type, field_docs) = resolve_type(
-                        field.domain.as_ref().or(field.kind.as_ref()).unwrap(),
-                        field.asserts.as_ref(),
-                    )?;
+                    let (field_type, field_docs) =
+                        get_invariants_with_type(field_type(field), field.asserts.as_ref());
                     if !field_docs.is_empty() {
                         println!("        /// {field_docs}");
                     }
@@ -143,8 +140,6 @@ fn codegen_class_defs(amqp: &Amqp) -> Result<()> {
         }
         println!("}}");
     }
-
-    Ok(())
 }
 
 fn amqp_type_to_rust_type(amqp_type: &str) -> &'static str {
@@ -161,13 +156,25 @@ fn amqp_type_to_rust_type(amqp_type: &str) -> &'static str {
     }
 }
 
+fn field_type(field: &Field) -> &String {
+    field.domain.as_ref().or(field.kind.as_ref()).unwrap()
+}
+
+fn resolve_type_from_domain(amqp: &Amqp, domain: &str) -> String {
+    amqp.domains
+        .iter()
+        .find(|d| d.name == domain)
+        .map(|d| d.kind.clone())
+        .unwrap()
+}
+
 /// returns (type name, invariant docs)
-fn resolve_type(domain: &str, asserts: &[Assert]) -> Result<(String, String)> {
+fn get_invariants_with_type(domain: &str, asserts: &[Assert]) -> (String, String) {
     let additional_docs = invariants(asserts.iter());
 
     let type_name = domain.to_upper_camel_case();
 
-    Ok((type_name, additional_docs))
+    (type_name, additional_docs)
 }
 
 fn snake_case(ident: &str) -> String {

amqp_codegen/src/parser.rs

@@ -1,5 +1,6 @@
-use crate::{Amqp, Class, Domain, Method};
-use anyhow::Result;
+use crate::{
+    field_type, resolve_type_from_domain, snake_case, Amqp, Assert, Class, Domain, Method,
+};
 use heck::{ToSnakeCase, ToUpperCamelCase};
 use itertools::Itertools;
 
@@ -15,7 +16,7 @@ fn domain_function_name(domain_name: &str) -> String {
     format!("domain_{domain_name}")
 }
 
-pub(crate) fn codegen_parser(amqp: &Amqp) -> Result<()> {
+pub(crate) fn codegen_parser(amqp: &Amqp) {
     println!(
         "pub mod parse {{
 use super::*;
@@ -39,7 +40,7 @@ pub type IResult<'a, T> = nom::IResult<&'a [u8], T, TransError>;
     );
 
     for domain in &amqp.domains {
-        domain_parser(domain)?;
+        domain_parser(domain);
     }
 
     for class in &amqp.classes {
@@ -56,78 +57,120 @@ pub type IResult<'a, T> = nom::IResult<&'a [u8], T, TransError>;
                 "    let (input, _) = tag([{class_index}])(input)?;
     alt(({all_methods}))(input)"
             );
-
-            Ok(())
-        })?;
+        });
 
         for method in &class.methods {
-            method_parser(class, method)?;
+            method_parser(amqp, class, method);
         }
     }
 
     println!("\n}}");
-    Ok(())
 }
 
-fn domain_parser(domain: &Domain) -> Result<()> {
+fn domain_parser(domain: &Domain) {
     let fn_name = domain_function_name(&domain.name);
     let type_name = domain.kind.to_snake_case();
-    function(&fn_name, &domain.name.to_upper_camel_case(), || {
-        if domain.asserts.is_empty() {
-            if type_name == "bit" {
-                println!("    todo!() // bit")
-            } else {
+    // don't even bother with bit domains, do them manually at call site
+    if type_name != "bit" {
+        function(&fn_name, &domain.name.to_upper_camel_case(), || {
+            if domain.asserts.is_empty() {
                 println!("    {type_name}(input)");
-            }
-        } else {
-            println!("    let (input, result) = {type_name}(input)?;");
+            } else {
+                println!("    let (input, result) = {type_name}(input)?;");
 
-            for assert in &domain.asserts {
-                match &*assert.check {
-                    "notnull" => { /* todo */ }
-                    "regexp" => {
-                        let value = assert.value.as_ref().unwrap();
-                        println!(
-                            r#"    static REGEX: Lazy<Regex> = Lazy::new(|| Regex::new(r"{value}").unwrap());"#
-                        );
-                        println!("    if !REGEX.is_match(&result) {{ fail!() }}");
-                    }
-                    "le" => {} // can't validate this here
-                    "length" => {
-                        let length = assert.value.as_ref().unwrap();
-                        println!("    if result.len() > {length} {{ fail!() }}");
-                    }
-                    _ => unimplemented!(),
+                for assert in &domain.asserts {
+                    assert_check(assert, &type_name, "result");
                 }
+                println!("    Ok((input, result))");
             }
-            println!("    Ok((input, result))");
-        }
-        Ok(())
-    })
+        });
+    }
 }
 
-fn method_parser(class: &Class, method: &Method) -> Result<()> {
+fn method_parser(amqp: &Amqp, class: &Class, method: &Method) {
     let class_name = class.name.to_snake_case();
 
     let function_name = method_function_name(&class_name)(method);
     function(&function_name, "Class", || {
         let method_index = method.index;
         println!("    let (input, _) = tag([{method_index}])(input)?;");
-        println!("    todo!()");
-        for _field in &method.fields {}
-        Ok(())
-    })?;
+        let mut iter = method.fields.iter().peekable();
+        while let Some(field) = iter.next() {
+            let type_name = resolve_type_from_domain(amqp, field_type(field));
 
-    Ok(())
+            if type_name == "bit" {
+                let mut fields_with_bit = vec![field];
+
+                loop {
+                    if iter
+                        .peek()
+                        .map(|f| resolve_type_from_domain(amqp, field_type(f)) == "bit")
+                        .unwrap_or(false)
+                    {
+                        fields_with_bit.push(iter.next().unwrap());
+                    } else {
+                        break;
+                    }
+                }
+
+                let amount = fields_with_bit.len();
+                println!("    let (input, bits) = bit(input, {amount})?;");
+
+                for (i, field) in fields_with_bit.iter().enumerate() {
+                    let field_name = snake_case(&field.name);
+                    println!("    let {field_name} = bits[{i}];");
+                }
+            } else {
+                let fn_name = domain_function_name(field_type(field));
+                let field_name = snake_case(&field.name);
+                println!("    let (input, {field_name}) = {fn_name}(input)?;");
+
+                for assert in &field.asserts {
+                    assert_check(assert, &type_name, &field_name);
+                }
+            }
+        }
+        let class_name = class_name.to_upper_camel_case();
+        let method_name = method.name.to_upper_camel_case();
+        println!("   Ok((input, Class::{class_name}({class_name}::{method_name} {{");
+        for field in &method.fields {
+            let field_name = snake_case(&field.name);
+            println!("        {field_name},");
+        }
+        println!("    }})))");
+    });
 }
 
-fn function<F>(name: &str, ret_ty: &str, body: F) -> Result<()>
+fn assert_check(assert: &Assert, type_name: &str, var_name: &str) {
+    match &*assert.check {
+        "notnull" => match type_name {
+            "shortstr" | "longstr" => {
+                println!("    if {var_name}.is_empty() {{ fail!() }}")
+            }
+            "short" => println!("    if {var_name} == 0 {{ fail!() }}"),
+            _ => unimplemented!(),
+        },
+        "regexp" => {
+            let value = assert.value.as_ref().unwrap();
+            println!(
+                r#"    static REGEX: Lazy<Regex> = Lazy::new(|| Regex::new(r"{value}").unwrap());"#
+            );
+            println!("    if !REGEX.is_match(&{var_name}) {{ fail!() }}");
+        }
+        "le" => {} // can't validate this here
+        "length" => {
+            let length = assert.value.as_ref().unwrap();
+            println!("    if {var_name}.len() > {length} {{ fail!() }}");
+        }
+        _ => unimplemented!(),
+    }
+}
+
+fn function<F>(name: &str, ret_ty: &str, body: F)
 where
-    F: FnOnce() -> Result<()>,
+    F: FnOnce(),
 {
     println!("fn {name}(input: &[u8]) -> IResult<{ret_ty}> {{");
-    body()?;
+    body();
     println!("}}");
-
-    Ok(())
 }

amqp_transport/src/classes/mod.rs

@@ -1,3 +1,5 @@
+use crate::classes::generated::Class;
+use crate::error::{ConException, ProtocolError, TransError};
 use std::collections::HashMap;
 
 mod generated;
@@ -5,6 +7,7 @@ mod parse_helper;
 
 pub type Table = HashMap<String, FieldValue>;
 
+#[derive(Debug, Clone, PartialEq)]
 pub enum FieldValue {
     Boolean(bool),
     ShortShortInt(i8),
@@ -25,3 +28,19 @@ pub enum FieldValue {
     FieldTable(Table),
     Void,
 }
+
+pub use generated::*;
+
+/// Parses the payload of a method frame into the class/method
+pub fn parse_method(payload: &[u8]) -> Result<Class, TransError> {
+    let nom_result = generated::parse::parse_method(payload);
+
+    match nom_result {
+        Ok(([], class)) => Ok(class),
+        Ok((_, _)) => Err(ProtocolError::ConException(ConException::SyntaxError).into()),
+        Err(nom::Err::Incomplete(_)) => {
+            Err(ProtocolError::ConException(ConException::SyntaxError).into())
+        }
+        Err(nom::Err::Failure(err) | nom::Err::Error(err)) => Err(err),
+    }
+}

amqp_transport/src/classes/parse_helper.rs

@@ -39,6 +39,7 @@ pub fn long(input: &[u8]) -> IResult<Long> {
 pub fn longlong(input: &[u8]) -> IResult<Longlong> {
     todo!()
 }
+// todo: doing this using a vec is a bit wasteful, consider not doing that
 pub fn bit(input: &[u8], amount: u8) -> IResult<Vec<Bit>> {
     todo!()
 }

amqp_transport/src/connection.rs

@@ -1,5 +1,6 @@
 use crate::error::{ProtocolError, TransError};
 use crate::frame;
+use crate::frame::FrameType;
 use anyhow::Context;
 use tokio::io::{AsyncReadExt, AsyncWriteExt};
 use tokio::net::TcpStream;
@@ -27,6 +28,10 @@ impl Connection {
         loop {
             let frame = frame::read_frame(&mut self.stream, 10000).await?;
             debug!(?frame, "received frame");
+            if frame.kind == FrameType::Method {
+                let class = super::classes::parse_method(&frame.payload)?;
+                debug!(?class, "was method frame");
+            }
         }
     }
 

amqp_transport/src/frame.rs

@@ -14,10 +14,10 @@ mod frame_type {
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct Frame {
     /// The type of the frame including its parsed metadata.
-    kind: FrameType,
-    channel: u16,
+    pub kind: FrameType,
+    pub channel: u16,
     /// Includes the whole payload, also including the metadata from each type.
-    payload: Vec<u8>,
+    pub payload: Vec<u8>,
 }
 
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -29,23 +29,6 @@ pub enum FrameType {
     Heartbeat = 8,
 }
 
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub enum FrameTypeEnum {
-    /// 1
-    Method,
-    /// 2
-    Header {
-        class_id: u16,
-        body_size: u64,
-        /// Ordered from high to low    
-        property_flags: u16,
-    },
-    /// 3
-    Body,
-    /// 8
-    Heartbeat,
-}
-
 pub async fn read_frame<R>(r: &mut R, max_frame_size: usize) -> Result<Frame, TransError>
 where
     R: AsyncReadExt + Unpin,