test: poc openapi v3 codegen

As a start try to generate the same code as https://github.com/openebs/openapi-generator/blob/rust_mayastor/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/RustMayastorCodegen.java

Signed-off-by: Tiago Castro <[email protected]>

Cargo.toml

@@ -20,6 +20,7 @@ required-features = ["cli"]
 paperclip-actix = { path = "plugins/actix-web", version = "0.7.0", optional = true }
 paperclip-core = { path = "core", version = "0.7.0" }
 paperclip-macros = { path = "macros", version = "0.6.3", optional = true }
+paperclip-codegen = { path = "codegen", version = "0.1.0", optional = true }
 
 env_logger = { version = "0.8", optional = true }
 git2 = { version = "0.15", optional = true }
@@ -40,7 +41,7 @@ url_dep = { version = ">=1.7,<3", package = "url" }
 thiserror = "1.0"
 anyhow = "1.0"
 once_cell = "1.4"
-openapiv3 = { version = "1.0.3", optional = true }
+openapiv3 = { version = "2.0.0", optional = true }
 
 [dev-dependencies]
 actix-rt1 = { version = "1.0", package = "actix-rt" }
@@ -83,7 +84,8 @@ codegen = ["heck", "http", "log", "regex", "tinytemplate", "paperclip-core/codeg
 v2 = ["paperclip-macros/v2", "paperclip-core/v2"]
 # OpenAPI v2 to v3 support
 v3 = ["openapiv3", "v2", "paperclip-core/v3", "paperclip-actix/v3"]
-
+# Experimental V3 CodeGen
+v3-poc = ["paperclip-codegen", "openapiv3"]
 
 # Features for implementing traits for dependencies.
 actix-multipart = ["paperclip-core/actix-multipart"]
@@ -106,6 +108,7 @@ members = [
     "core",
     "macros",
     "plugins/actix-web",
+    "codegen"
 ]
 
 [[test]]

codegen/Cargo.toml

@@ -0,0 +1,35 @@
+[package]
+name = "paperclip-codegen"
+version = "0.1.0"
+edition = "2018"
+license = "MIT OR Apache-2.0"
+keywords = [ "openapi", "openapiv3", "codegen" ]
+description = "Experimental OpenAPI V3.0.3 Code Generator"
+homepage = "https://github.com/paperclip-rs/paperclip"
+repository = "https://github.com/paperclip-rs/paperclip"
+
+[lib]
+
+[[bin]]
+name = "paperclip-cli"
+path = "src/bin/codegen/main.rs"
+
+[dependencies]
+ramhorns = { version = "1.0", default-features = false, features = ["indexes"], optional = true }
+ramhorns-derive = { version = "1.0", optional = true }
+openapiv3 = { version = "2.0.0", optional = true }
+heck = { version = "0.4", optional = true }
+itertools = { version = "0.10", optional = true }
+
+env_logger = "0.8"
+log = { version = "0.4", features = ["kv_unstable"] }
+structopt = { version = "0.3" }
+serde_json = "1.0"
+serde_yaml = "0.9"
+thiserror = "1.0"
+
+
+[features]
+default = [ "poc" ]
+ramhorns-feat = [ "ramhorns", "ramhorns-derive" ]
+poc = [ "ramhorns-feat", "openapiv3", "heck", "itertools" ]

codegen/src/bin/codegen/error.rs

@@ -0,0 +1,30 @@
+macro_rules! impl_err_from {
+    ($err:ident :: $type:ty > $variant:ident) => {
+        impl From<$type> for $err {
+            fn from(s: $type) -> Self {
+                $err::$variant(s)
+            }
+        }
+    };
+}
+
+/// Global error which encapsulates all related errors.
+#[derive(Debug, thiserror::Error)]
+pub(crate) enum Error {
+    /// The given directory cannot be used for generating code.
+    #[error("Cannot generate code in the given directory")]
+    InvalidCodegenDirectory,
+    /// I/O errors.
+    #[error("I/O error: {}", _0)]
+    Io(std::io::Error),
+    /// JSON coding errors.
+    #[error("JSON error: {}", _0)]
+    Json(serde_json::Error),
+    /// YAML coding errors.
+    #[error("YAML error: {}", _0)]
+    Yaml(serde_yaml::Error),
+}
+
+impl_err_from!(Error::std::io::Error > Io);
+impl_err_from!(Error::serde_json::Error > Json);
+impl_err_from!(Error::serde_yaml::Error > Yaml);

codegen/src/bin/codegen/main.rs

@@ -0,0 +1,94 @@
+use heck::ToSnakeCase;
+use std::{
+    fs::{self, File},
+    io::Read,
+    path::PathBuf,
+};
+use structopt::StructOpt;
+
+mod error;
+use error::Error;
+
+/// Deserialize the schema from the given reader. Currently, this only supports
+/// JSON and YAML formats.
+fn from_reader_v3<R>(mut reader: R) -> Result<openapiv3::OpenAPI, Error>
+where
+    R: Read,
+{
+    let mut buf = [b' '];
+    while buf[0].is_ascii_whitespace() {
+        reader.read_exact(&mut buf)?;
+    }
+    let reader = buf.as_ref().chain(reader);
+
+    Ok(if buf[0] == b'{' {
+        serde_json::from_reader::<_, openapiv3::OpenAPI>(reader)?
+    } else {
+        serde_yaml::from_reader::<_, openapiv3::OpenAPI>(reader)?
+    })
+}
+fn parse_spec_v3(s: &str) -> Result<openapiv3::OpenAPI, Error> {
+    let fd = File::open(s)?;
+    from_reader_v3(fd)
+}
+
+#[derive(Debug, StructOpt)]
+struct Opt {
+    /// Path to OpenAPI spec in JSON/YAML format (also supports publicly accessible URLs).
+    #[structopt(long)]
+    spec: std::path::PathBuf,
+    /// Output directory to write code (default: current working directory).
+    #[structopt(short = "o", long = "out", parse(from_os_str))]
+    output: Option<PathBuf>,
+    /// Don't Render models.
+    #[structopt(long)]
+    no_models: bool,
+    /// Don't Render operations.
+    #[structopt(long)]
+    no_ops: bool,
+    /// Name of the crate. If this is not specified, then the name of the
+    /// working directory is assumed to be crate name.
+    #[structopt(long = "name")]
+    pub name: Option<String>,
+    /// The Version of the crate.
+    #[structopt(long = "version", default_value = "0.1.0")]
+    pub version: String,
+    /// The Edition of the crate.
+    #[structopt(long = "edition", default_value = "2018")]
+    pub edition: String,
+}
+
+fn parse_args_and_run() -> Result<(), Error> {
+    let opt: Opt = Opt::from_args();
+
+    if let Some(o) = &opt.output {
+        fs::create_dir_all(o)?;
+    }
+
+    let spec = parse_spec_v3(opt.spec.to_string_lossy().as_ref())?;
+    let name = opt.name.map(Ok::<String, Error>).unwrap_or_else(|| {
+        Ok(fs::canonicalize(std::path::Path::new("."))?
+            .file_name()
+            .ok_or(Error::InvalidCodegenDirectory)?
+            .to_string_lossy()
+            .into_owned()
+            .to_snake_case())
+    })?;
+    let info = paperclip_codegen::v3_03::PackageInfo {
+        libname: name.to_snake_case(),
+        name,
+        version: opt.version,
+        edition: opt.edition,
+    };
+
+    paperclip_codegen::v3_03::OpenApiV3::new(spec, opt.output, info)
+        .run(!opt.no_models, !opt.no_ops)?;
+    Ok(())
+}
+
+fn main() {
+    env_logger::init();
+    if let Err(e) = parse_args_and_run() {
+        eprintln!("{}", e);
+    }
+}

codegen/src/lib.rs

@@ -0,0 +1,9 @@
+mod v3;
+
+pub mod v3_03 {
+    pub use super::v3::{OpenApiV3, PackageInfo};
+}
+
+#[cfg_attr(feature = "ramhorns-feat", macro_use)]
+#[cfg(feature = "ramhorns-feat")]
+extern crate log;