progenitor/progenitor-impl/src/template.rs

339 lines
10 KiB
Rust

// Copyright 2022 Oxide Computer Company
use std::collections::HashMap;
use proc_macro2::TokenStream;
use quote::{format_ident, quote};
use crate::{Error, Result};
#[derive(Eq, PartialEq, Clone, Debug)]
enum Component {
Constant(String),
Parameter(String),
}
#[derive(Eq, PartialEq, Clone, Debug)]
pub struct PathTemplate {
components: Vec<Component>,
}
impl PathTemplate {
pub fn compile(
&self,
rename: HashMap<&String, &String>,
client: TokenStream,
) -> TokenStream {
let mut fmt = String::new();
fmt.push_str("{}");
for c in self.components.iter() {
match c {
Component::Constant(n) => fmt.push_str(n),
Component::Parameter(_) => fmt.push_str("{}"),
}
}
let components = self.components.iter().filter_map(|component| {
if let Component::Parameter(n) = &component {
let param = format_ident!(
"{}",
rename
.get(&n)
.expect(&format!("missing path name mapping {}", n)),
);
Some(quote! {
encode_path(&#param.to_string())
})
} else {
None
}
});
quote! {
format!(#fmt, #client.baseurl, #(#components,)*)
}
}
pub fn names(&self) -> Vec<String> {
self.components
.iter()
.filter_map(|c| match c {
Component::Parameter(name) => Some(name.to_string()),
Component::Constant(_) => None,
})
.collect()
}
pub fn as_wildcard(&self) -> String {
let inner = self
.components
.iter()
.map(|c| match c {
Component::Constant(name) => name.clone(),
Component::Parameter(_) => "[^/]*".to_string(),
})
.collect::<String>();
format!("^{}$", inner)
}
pub fn as_wildcard_param(&self, param: &str) -> String {
let inner = self
.components
.iter()
.map(|c| match c {
Component::Constant(name) => name.clone(),
Component::Parameter(p) if p == param => "{}".to_string(),
Component::Parameter(_) => ".*".to_string(),
})
.collect::<String>();
format!("^{}$", inner)
}
}
pub fn parse(t: &str) -> Result<PathTemplate> {
enum State {
Start,
ConstantOrParameter,
Parameter,
Constant,
}
let mut s = State::Start;
let mut a = String::new();
let mut components = Vec::new();
for c in t.chars() {
match s {
State::Start => {
if c == '/' {
s = State::Constant;
a = c.to_string();
} else {
return Err(Error::InvalidPath(
"path must start with a slash".to_string(),
));
}
}
State::ConstantOrParameter => {
if c == '{' {
s = State::Parameter;
a = String::new();
} else {
s = State::Constant;
a = c.to_string();
}
}
State::Constant => {
if c == '{' {
components.push(Component::Constant(a));
a = String::new();
s = State::Parameter;
} else if c == '}' {
return Err(Error::InvalidPath("unexpected }".to_string()));
} else if c != '/' || !a.ends_with('/') {
a.push(c);
}
}
State::Parameter => {
if c == '}' {
if a.contains('/') || a.contains('{') {
return Err(Error::InvalidPath(format!(
"invalid parameter name {:?}",
a,
)));
}
components.push(Component::Parameter(a));
a = String::new();
s = State::ConstantOrParameter;
} else {
a.push(c);
}
}
}
}
match s {
State::Start => {
return Err(Error::InvalidPath("empty path".to_string()))
}
State::ConstantOrParameter => (),
State::Constant => components.push(Component::Constant(a)),
State::Parameter => {
return Err(Error::InvalidPath(
"unterminated parameter".to_string(),
))
}
}
Ok(PathTemplate { components })
}
impl ToString for PathTemplate {
fn to_string(&self) -> std::string::String {
self.components
.iter()
.map(|component| match component {
Component::Constant(s) => s.clone(),
Component::Parameter(s) => format!("{{{}}}", s),
})
.fold(String::new(), |a, b| a + &b)
}
}
#[cfg(test)]
mod tests {
use std::collections::HashMap;
use super::{parse, Component, PathTemplate};
#[test]
fn basic() {
let trials = vec![
(
"/info",
"/info",
PathTemplate {
components: vec![Component::Constant("/info".into())],
},
),
(
"/measure/{number}",
"/measure/{number}",
PathTemplate {
components: vec![
Component::Constant("/measure/".into()),
Component::Parameter("number".into()),
],
},
),
(
"/one/{two}/three",
"/one/{two}/three",
PathTemplate {
components: vec![
Component::Constant("/one/".into()),
Component::Parameter("two".into()),
Component::Constant("/three".into()),
],
},
),
(
"/{foo}-{bar}-{baz}",
"/{foo}-{bar}-{baz}",
PathTemplate {
components: vec![
Component::Constant("/".into()),
Component::Parameter("foo".into()),
Component::Constant("-".into()),
Component::Parameter("bar".into()),
Component::Constant("-".into()),
Component::Parameter("baz".into()),
],
},
),
(
"//normalise/////{adjacent}:x///slashes",
"/normalise/{adjacent}:x/slashes",
PathTemplate {
components: vec![
Component::Constant("/normalise/".into()),
Component::Parameter("adjacent".into()),
Component::Constant(":x/slashes".into()),
],
},
),
(
"/v1/files/{fileId}:completeUpload",
"/v1/files/{fileId}:completeUpload",
PathTemplate {
components: vec![
Component::Constant("/v1/files/".into()),
Component::Parameter("fileId".into()),
Component::Constant(":completeUpload".into()),
],
},
),
(
"/v1/folders/{folderId}/sessions/{sessionId}:complete",
"/v1/folders/{folderId}/sessions/{sessionId}:complete",
PathTemplate {
components: vec![
Component::Constant("/v1/folders/".into()),
Component::Parameter("folderId".into()),
Component::Constant("/sessions/".into()),
Component::Parameter("sessionId".into()),
Component::Constant(":complete".into()),
],
},
),
];
for (path, expect_string, want) in trials.iter() {
match parse(path) {
Ok(t) => {
assert_eq!(&t, want);
assert_eq!(t.to_string().as_str(), *expect_string);
}
Err(e) => panic!("path {} {}", path, e),
}
}
}
#[test]
fn names() {
let trials = vec![
("/info", vec![]),
("/measure/{number}", vec!["number".to_string()]),
(
"/measure/{one}/{two}/and/{three}/yeah",
vec!["one".to_string(), "two".to_string(), "three".to_string()],
),
];
for (path, want) in trials.iter() {
match parse(path) {
Ok(t) => assert_eq!(&t.names(), want),
Err(e) => panic!("path {} {}", path, e),
}
}
}
#[test]
fn compile() {
let mut rename = HashMap::new();
let number = "number".to_string();
rename.insert(&number, &number);
let t = parse("/measure/{number}").unwrap();
let out = t.compile(rename, quote::quote! { self });
let want = quote::quote! {
format!("{}/measure/{}",
self.baseurl,
encode_path(&number.to_string()),
)
};
assert_eq!(want.to_string(), out.to_string());
}
#[test]
fn compile2() {
let mut rename = HashMap::new();
let one = "one".to_string();
let two = "two".to_string();
let three = "three".to_string();
rename.insert(&one, &one);
rename.insert(&two, &two);
rename.insert(&three, &three);
let t = parse("/abc/def:{one}:jkl/{two}/a:{three}").unwrap();
let out = t.compile(rename, quote::quote! { self });
let want = quote::quote! {
format!("{}/abc/def:{}:jkl/{}/a:{}",
self.baseurl,
encode_path(&one.to_string()),
encode_path(&two.to_string()),
encode_path(&three.to_string()),
)
};
assert_eq!(want.to_string(), out.to_string());
}
}