cargo-typify

Once installed, the following command converts a JSON Schema file into Rust code:

$ cargo typify my_types.json

This is a wrapper around the typify crate for use at the command-line.

Installation

Install with cargo install cargo-typify. This command requires that rustfmt is installed. Install rustfmt with rustup component add rustfmt

Example

$ cat id-or-name.json

{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "definitions": {
    "IdOrName": {
      "oneOf": [
        {
          "title": "Id",
          "allOf": [
            {
              "type": "string",
              "format": "uuid"
            }
          ]
        },
        {
          "title": "Name",
          "allOf": [
            {
              "$ref": "#/definitions/Name"
            }
          ]
        }
      ]
    },
    "Name": {
      "title": "A name unique within the parent collection",
      "description": "Names must begin with a lower case ASCII letter, be composed exclusively of lowercase ASCII, uppercase ASCII, numbers, and '-', and may not end with a '-'. Names cannot be a UUID though they may contain a UUID.",
      "type": "string",
      "pattern": "^(?![0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$)^[a-z][a-z0-9-]*[a-zA-Z0-9]$",
      "maxLength": 63
    }
  }
}

$ cargo typify id-or-name.json && cat id-or-name.rs

#![allow(clippy::redundant_closure_call)]
#![allow(clippy::needless_lifetimes)]
#![allow(clippy::match_single_binding)]
#![allow(clippy::clone_on_copy)]

#[derive(Clone, Debug, serde::Deserialize, serde::Serialize)]
#[serde(untagged)]
pub enum IdOrName {
    Id(uuid::Uuid),
    Name(Name),
}
impl From<&IdOrName> for IdOrName {
    fn from(value: &IdOrName) -> Self {
        value.clone()
    }
}
impl std::str::FromStr for IdOrName {
    type Err = &'static str;
    fn from_str(value: &str) -> Result<Self, &'static str> {
        if let Ok(v) = value.parse() {
            Ok(Self::Id(v))
        } else if let Ok(v) = value.parse() {
            Ok(Self::Name(v))
        } else {
            Err("string conversion failed for all variants")
        }
    }
}
impl std::convert::TryFrom<&str> for IdOrName {
    type Error = &'static str;
    fn try_from(value: &str) -> Result<Self, &'static str> {
        value.parse()
    }
}
impl std::convert::TryFrom<&String> for IdOrName {
    type Error = &'static str;
    fn try_from(value: &String) -> Result<Self, &'static str> {
        value.parse()
    }
}
impl std::convert::TryFrom<String> for IdOrName {
    type Error = &'static str;
    fn try_from(value: String) -> Result<Self, &'static str> {
        value.parse()
    }
}
impl ::std::fmt::Display for IdOrName {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        match self {
            Self::Id(x) => x.fmt(f),
            Self::Name(x) => x.fmt(f),
        }
    }
}
impl From<uuid::Uuid> for IdOrName {
    fn from(value: uuid::Uuid) -> Self {
        Self::Id(value)
    }
}
impl From<Name> for IdOrName {
    fn from(value: Name) -> Self {
        Self::Name(value)
    }
}
#[doc = "Names must begin with a lower case ASCII letter, be composed exclusively of lowercase ASCII, uppercase ASCII, numbers, and '-', and may not end with a '-'. Names cannot be a UUID though they may contain a UUID."]
#[derive(Clone, Debug, Serialize)]
pub struct Name(String);
impl std::ops::Deref for Name {
    type Target = String;
    fn deref(&self) -> &String {
        &self.0
    }
}
impl From<Name> for String {
    fn from(value: Name) -> Self {
        value.0
    }
}
impl From<&Name> for Name {
    fn from(value: &Name) -> Self {
        value.clone()
    }
}
impl std::str::FromStr for Name {
    type Err = &'static str;
    fn from_str(value: &str) -> Result<Self, &'static str> {
        if value.len() > 63usize {
            return Err("longer than 63 characters");
        }
        if regress::Regex::new("^(?![0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$)^[a-z][a-z0-9-]*[a-zA-Z0-9]$")
            .unwrap()
            .find(value)
            .is_none()
        {
            return Err("doesn't match pattern \"^(?![0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$)^[a-z][a-z0-9-]*[a-zA-Z0-9]$\"");
        }
        Ok(Self(value.to_string()))
    }
}
impl std::convert::TryFrom<&str> for Name {
    type Error = &'static str;
    fn try_from(value: &str) -> Result<Self, &'static str> {
        value.parse()
    }
}
impl std::convert::TryFrom<&String> for Name {
    type Error = &'static str;
    fn try_from(value: &String) -> Result<Self, &'static str> {
        value.parse()
    }
}
impl std::convert::TryFrom<String> for Name {
    type Error = &'static str;
    fn try_from(value: String) -> Result<Self, &'static str> {
        value.parse()
    }
}
impl<'de> serde::Deserialize<'de> for Name {
    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
    where
        D: serde::Deserializer<'de>,
    {
        String::deserialize(deserializer)?
            .parse()
            .map_err(|e: &'static str| <D::Error as serde::de::Error>::custom(e.to_string()))
    }
}

Options

See cargo typify --help for a complete list of options.

The --output option lets you override the default output file (replacing the input file extension with .rs). Use - for stdout.

Use --no-builder to disable struct builder generation (--builder is the default). Builder output lets you write code like this:

let xy: MyStruct = MyStruct::builder().x_coord(x).y_coord(y).try_into();

The --additional-derive adds the specified derive macro to all generated types. This may be specified more than once.