From 4da96aef81d9b29552f299685f627dbd09a7551d Mon Sep 17 00:00:00 2001
From: dzmitry-lahoda <dzmitry@lahoda.pro>
Date: Tue, 5 Dec 2023 22:35:43 +0000
Subject: [PATCH] improvement(primitive-types): better json-schema, allow to
 build for serde_no_std/json-schema feature/targets combinations (#801)

* more std

* fixes of std and improvement of schema

* better alloc support
---
 primitive-types/Cargo.toml         |  2 +
 primitive-types/src/json_schema.rs | 75 ++++++++++++++++++++++++++++++
 primitive-types/src/lib.rs         | 23 +++------
 3 files changed, 83 insertions(+), 17 deletions(-)
 create mode 100644 primitive-types/src/json_schema.rs

diff --git a/primitive-types/Cargo.toml b/primitive-types/Cargo.toml
index 126b17dc..1c861d36 100644
--- a/primitive-types/Cargo.toml
+++ b/primitive-types/Cargo.toml
@@ -20,6 +20,8 @@ schemars = { version = ">=0.8.12", default-features = true, optional = true }
 
 [dev-dependencies]
 num-traits = "0.2"
+serde_json = { version = "1.0", default-features = false }
+jsonschema = { version = "0.17", default-features = false }
 
 [features]
 default = ["std"]
diff --git a/primitive-types/src/json_schema.rs b/primitive-types/src/json_schema.rs
new file mode 100644
index 00000000..948bf86c
--- /dev/null
+++ b/primitive-types/src/json_schema.rs
@@ -0,0 +1,75 @@
+use super::*;
+#[cfg(not(feature = "std"))]
+use alloc::{
+	borrow::ToOwned,
+	string::{String, ToString},
+};
+
+use schemars::{gen::SchemaGenerator, schema::Schema, JsonSchema};
+
+impl JsonSchema for H160 {
+	fn schema_name() -> String {
+		"HexEncoded20Bytes".to_owned()
+	}
+
+	fn json_schema(gen: &mut SchemaGenerator) -> Schema {
+		let mut schema = gen.subschema_for::<String>().into_object();
+		schema.metadata().description = Some("Hex encoded 20 bytes".to_string());
+		schema.string().pattern = Some("^0(x|X)[a-fA-F0-9]{40}$".to_string());
+		schema.into()
+	}
+}
+
+impl JsonSchema for U256 {
+	fn schema_name() -> String {
+		"U256String".to_string()
+	}
+
+	fn json_schema(gen: &mut SchemaGenerator) -> Schema {
+		let mut schema = gen.subschema_for::<String>().into_object();
+		schema.metadata().description = Some("256-bit Unsigned Integer".to_string());
+		schema.string().pattern = Some("^(0|[1-9][0-9]{0,77})$".to_string());
+		schema.into()
+	}
+}
+
+#[cfg(test)]
+#[cfg(any(feature = "serde", feature = "serde_no_std"))]
+mod tests {
+	use crate::{H160, U256};
+	#[cfg(not(feature = "std"))]
+	use alloc::string::String;
+	use jsonschema::Draft;
+	use schemars::JsonSchema;
+
+	#[test]
+	fn hex_encoded_20_bytes() {
+		let schema = H160::json_schema(&mut schemars::gen::SchemaGenerator::default());
+		let schema_json = serde_json::to_value(&schema).unwrap();
+		let schema = jsonschema::JSONSchema::options()
+			.with_draft(Draft::Draft7)
+			.compile(&schema_json)
+			.unwrap();
+		let value = serde_json::to_value("0x55086adeca661185c437d92b9818e6eda6d0d047").unwrap();
+		assert!(schema.validate(&value).is_ok());
+		let value = serde_json::to_value("0X0E9C8DA9FD4BDD3281879D9E328D8D74D02558CC").unwrap();
+		assert!(schema.validate(&value).is_ok());
+
+		let value = serde_json::to_value("42").unwrap();
+		assert!(schema.validate(&value).is_err());
+	}
+
+	#[test]
+	fn u256() {
+		let schema = U256::json_schema(&mut schemars::gen::SchemaGenerator::default());
+		let schema_json = serde_json::to_value(&schema).unwrap();
+		let schema = jsonschema::JSONSchema::options()
+			.with_draft(Draft::Draft7)
+			.compile(&schema_json)
+			.unwrap();
+		let addr = serde_json::to_value("42").unwrap();
+		assert!(schema.validate(&addr).is_ok());
+		let addr = serde_json::to_value(['1'; 79].into_iter().collect::<String>()).unwrap();
+		assert!(schema.validate(&addr).is_err());
+	}
+}
diff --git a/primitive-types/src/lib.rs b/primitive-types/src/lib.rs
index d80a312f..41b74029 100644
--- a/primitive-types/src/lib.rs
+++ b/primitive-types/src/lib.rs
@@ -14,8 +14,14 @@
 
 #![cfg_attr(not(feature = "std"), no_std)]
 
+// serde_no_std leads to alloc via impl, json-schema without std requires alloc
+#[cfg(all(not(feature = "std"), any(feature = "serde_no_std", feature = "json-schema")))]
+extern crate alloc;
+
 #[cfg(feature = "fp-conversion")]
 mod fp_conversion;
+#[cfg(feature = "json-schema")]
+mod json_schema;
 
 use core::convert::TryFrom;
 use fixed_hash::{construct_fixed_hash, impl_fixed_hash_conversions};
@@ -105,23 +111,6 @@ mod serde {
 	impl_fixed_hash_serde!(H768, 96);
 }
 
-// true that no need std, but need to do no_std alloc than, so simplified for now
-// also no macro, but easy to create
-#[cfg(all(feature = "std", feature = "json-schema"))]
-mod json_schema {
-	use super::*;
-
-	impl schemars::JsonSchema for H160 {
-		fn schema_name() -> String {
-			"0xPrefixedHexString".to_string()
-		}
-
-		fn json_schema(gen: &mut schemars::gen::SchemaGenerator) -> schemars::schema::Schema {
-			String::json_schema(gen)
-		}
-	}
-}
-
 #[cfg(feature = "impl-codec")]
 mod codec {
 	use super::*;