openethereum/hash-fetch/src/urlhint.rs
Niklas Adolfsson e0f71b0c17 [contract-client] refactor (#7978)
* Refactor usage of registry contract

* remove unsed file

* Rename methods & fix comments

* refactor contract_client:

* Intoduced separate traits for asyncronous and syncronous contract clients
* Removed registrar from ethcore::client
* s/ContractClient/AsyncContractClient

* make the tests compile and pass

* omit changes in ethcore

* Use only one trait for ContractClient

* Use an associated type in the trait to determine syncronous or asyncronous communication
* Export the types from contract-client crate
* Document that "A" in the hash correspons to a DNS A Record A.K.A Address Record

* contract_client -> registrar

* address review feedback
2018-03-12 20:46:27 +00:00

364 lines
11 KiB
Rust

// Copyright 2015-2017 Parity Technologies (UK) Ltd.
// This file is part of Parity.
// Parity is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Parity is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Parity. If not, see <http://www.gnu.org/licenses/>.
//! URLHint Contract
use std::sync::Arc;
use rustc_hex::ToHex;
use mime::{self, Mime};
use mime_guess;
use futures::{future, Future};
use futures::future::Either;
use ethereum_types::{H256, Address};
use registrar::{Registrar, RegistrarClient, Asynchronous};
use_contract!(urlhint, "Urlhint", "res/urlhint.json");
const COMMIT_LEN: usize = 20;
const GITHUB_HINT: &'static str = "githubhint";
/// GithubHint entries with commit set as `0x0..01` should be treated
/// as Github Dapp, downloadable zip files, than can be extracted, containing
/// the manifest.json file along with the dapp
static GITHUB_DAPP_COMMIT: &[u8; COMMIT_LEN] = &[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1];
/// Github-hosted dapp.
#[derive(Debug, PartialEq)]
pub struct GithubApp {
/// Github Account
pub account: String,
/// Github Repository
pub repo: String,
/// Commit on Github
pub commit: [u8; COMMIT_LEN],
/// Dapp owner address
pub owner: Address,
}
impl GithubApp {
/// Returns URL of this Github-hosted dapp package.
pub fn url(&self) -> String {
// Since https fetcher doesn't support redirections we use direct link
// format!("https://github.com/{}/{}/archive/{}.zip", self.account, self.repo, self.commit.to_hex())
format!("https://codeload.github.com/{}/{}/zip/{}", self.account, self.repo, self.commit.to_hex())
}
fn commit(bytes: &[u8]) -> Option<[u8;COMMIT_LEN]> {
if bytes.len() < COMMIT_LEN {
return None;
}
let mut commit = [0; COMMIT_LEN];
for i in 0..COMMIT_LEN {
commit[i] = bytes[i];
}
Some(commit)
}
}
/// Hash-Addressed Content
#[derive(Debug, PartialEq)]
pub struct Content {
/// URL of the content
pub url: String,
/// MIME type of the content
pub mime: Mime,
/// Content owner address
pub owner: Address,
}
/// Result of resolving id to URL
#[derive(Debug, PartialEq)]
pub enum URLHintResult {
/// Dapp
Dapp(GithubApp),
/// GithubDapp
GithubDapp(Content),
/// Content
Content(Content),
}
/// URLHint Contract interface
pub trait URLHint: Send + Sync {
/// Resolves given id to registrar entry.
fn resolve(&self, id: H256) -> Box<Future<Item = Option<URLHintResult>, Error = String> + Send>;
}
/// `URLHintContract` API
pub struct URLHintContract {
urlhint: urlhint::Urlhint,
registrar: Registrar,
client: Arc<RegistrarClient<Call=Asynchronous>>,
}
impl URLHintContract {
/// Creates new `URLHintContract`
pub fn new(client: Arc<RegistrarClient<Call=Asynchronous>>) -> Self {
URLHintContract {
urlhint: urlhint::Urlhint::default(),
registrar: Registrar::new(client.clone()),
client: client,
}
}
}
fn get_urlhint_content(account_slash_repo: String, owner: Address) -> Content {
let mime = guess_mime_type(&account_slash_repo).unwrap_or(mime::APPLICATION_JSON);
Content {
url: account_slash_repo,
mime,
owner,
}
}
fn decode_urlhint_output(output: (String, [u8; 20], Address)) -> Option<URLHintResult> {
let (account_slash_repo, commit, owner) = output;
if owner == Address::default() {
return None;
}
let commit = GithubApp::commit(&commit);
if commit == Some(Default::default()) {
let content = get_urlhint_content(account_slash_repo, owner);
return Some(URLHintResult::Content(content));
}
if commit == Some(*GITHUB_DAPP_COMMIT) {
let content = get_urlhint_content(account_slash_repo, owner);
return Some(URLHintResult::GithubDapp(content));
}
let (account, repo) = {
let mut it = account_slash_repo.split('/');
match (it.next(), it.next()) {
(Some(account), Some(repo)) => (account.into(), repo.into()),
_ => return None,
}
};
commit.map(|commit| URLHintResult::Dapp(GithubApp {
account: account,
repo: repo,
commit: commit,
owner: owner,
}))
}
impl URLHint for URLHintContract {
fn resolve(&self, id: H256) -> Box<Future<Item = Option<URLHintResult>, Error = String> + Send> {
let entries = self.urlhint.functions().entries();
let client = self.client.clone();
let future = self.registrar.get_address(GITHUB_HINT)
.and_then(move |addr| if !addr.is_zero() {
let data = entries.input(id);
let result = client.call_contract(addr, data)
.and_then(move |output| entries.output(&output).map_err(|e| e.to_string()))
.map(decode_urlhint_output);
Either::B(result)
} else {
Either::A(future::ok(None))
});
Box::new(future)
}
}
fn guess_mime_type(url: &str) -> Option<Mime> {
const CONTENT_TYPE: &'static str = "content-type=";
let mut it = url.split('#');
// skip url
let url = it.next();
// get meta headers
let metas = it.next();
if let Some(metas) = metas {
for meta in metas.split('&') {
let meta = meta.to_lowercase();
if meta.starts_with(CONTENT_TYPE) {
return meta[CONTENT_TYPE.len()..].parse().ok();
}
}
}
url.and_then(|url| {
url.split('.').last()
}).and_then(|extension| {
mime_guess::get_mime_type_opt(extension)
})
}
#[cfg(test)]
pub mod tests {
use std::sync::Arc;
use std::str::FromStr;
use rustc_hex::FromHex;
use futures::{Future, IntoFuture};
use super::*;
use super::guess_mime_type;
use parking_lot::Mutex;
use ethereum_types::Address;
use bytes::{Bytes, ToPretty};
pub struct FakeRegistrar {
pub calls: Arc<Mutex<Vec<(String, String)>>>,
pub responses: Mutex<Vec<Result<Bytes, String>>>,
}
pub const REGISTRAR: &'static str = "8e4e9b13d4b45cb0befc93c3061b1408f67316b2";
pub const URLHINT: &'static str = "deadbeefcafe0000000000000000000000000000";
impl FakeRegistrar {
pub fn new() -> Self {
FakeRegistrar {
calls: Arc::new(Mutex::new(Vec::new())),
responses: Mutex::new(
vec![
Ok(format!("000000000000000000000000{}", URLHINT).from_hex().unwrap()),
Ok(Vec::new())
]
),
}
}
}
impl RegistrarClient for FakeRegistrar {
type Call = Asynchronous;
fn registrar_address(&self) -> Result<Address, String> {
Ok(REGISTRAR.parse().unwrap())
}
fn call_contract(&self, address: Address, data: Bytes) -> Self::Call {
self.calls.lock().push((address.to_hex(), data.to_hex()));
let res = self.responses.lock().remove(0);
Box::new(res.into_future())
}
}
#[test]
fn should_call_registrar_and_urlhint_contracts() {
// given
let registrar = FakeRegistrar::new();
let resolve_result = {
use ethabi::{encode, Token};
encode(&[Token::String(String::new()), Token::FixedBytes(vec![0; 20]), Token::Address([0; 20].into())])
};
registrar.responses.lock()[1] = Ok(resolve_result);
let calls = registrar.calls.clone();
let urlhint = URLHintContract::new(Arc::new(registrar));
// when
let res = urlhint.resolve("test".as_bytes().into()).wait().unwrap();
let calls = calls.lock();
let call0 = calls.get(0).expect("Registrar resolve called");
let call1 = calls.get(1).expect("URLHint Resolve called");
// then
assert!(res.is_none());
assert_eq!(call0.0, REGISTRAR);
assert_eq!(call0.1,
"6795dbcd058740ee9a5a3fb9f1cfa10752baec87e09cc45cd7027fd54708271aca300c75000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000014100000000000000000000000000000000000000000000000000000000000000".to_owned()
);
assert_eq!(call1.0, URLHINT);
assert_eq!(call1.1,
"267b69227465737400000000000000000000000000000000000000000000000000000000".to_owned()
);
}
#[test]
fn should_decode_urlhint_output() {
// given
let mut registrar = FakeRegistrar::new();
registrar.responses = Mutex::new(vec![
Ok(format!("000000000000000000000000{}", URLHINT).from_hex().unwrap()),
Ok("0000000000000000000000000000000000000000000000000000000000000060ec4c1fe06c808fe3739858c347109b1f5f1ed4b5000000000000000000000000000000000000000000000000deadcafebeefbeefcafedeaddeedfeedffffffff0000000000000000000000000000000000000000000000000000000000000011657468636f72652f64616f2e636c61696d000000000000000000000000000000".from_hex().unwrap()),
]);
let urlhint = URLHintContract::new(Arc::new(registrar));
// when
let res = urlhint.resolve("test".as_bytes().into()).wait().unwrap();
// then
assert_eq!(res, Some(URLHintResult::Dapp(GithubApp {
account: "ethcore".into(),
repo: "dao.claim".into(),
commit: GithubApp::commit(&"ec4c1fe06c808fe3739858c347109b1f5f1ed4b5".from_hex().unwrap()).unwrap(),
owner: Address::from_str("deadcafebeefbeefcafedeaddeedfeedffffffff").unwrap(),
})))
}
#[test]
fn should_decode_urlhint_content_output() {
// given
let mut registrar = FakeRegistrar::new();
registrar.responses = Mutex::new(vec![
Ok(format!("000000000000000000000000{}", URLHINT).from_hex().unwrap()),
Ok("00000000000000000000000000000000000000000000000000000000000000600000000000000000000000000000000000000000000000000000000000000000000000000000000000000000deadcafebeefbeefcafedeaddeedfeedffffffff000000000000000000000000000000000000000000000000000000000000003c68747470733a2f2f7061726974792e696f2f6173736574732f696d616765732f657468636f72652d626c61636b2d686f72697a6f6e74616c2e706e6700000000".from_hex().unwrap()),
]);
let urlhint = URLHintContract::new(Arc::new(registrar));
// when
let res = urlhint.resolve("test".as_bytes().into()).wait().unwrap();
// then
assert_eq!(res, Some(URLHintResult::Content(Content {
url: "https://parity.io/assets/images/ethcore-black-horizontal.png".into(),
mime: mime::IMAGE_PNG,
owner: Address::from_str("deadcafebeefbeefcafedeaddeedfeedffffffff").unwrap(),
})))
}
#[test]
fn should_return_valid_url() {
// given
let app = GithubApp {
account: "test".into(),
repo: "xyz".into(),
commit: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19],
owner: Address::default(),
};
// when
let url = app.url();
// then
assert_eq!(url, "https://codeload.github.com/test/xyz/zip/000102030405060708090a0b0c0d0e0f10111213".to_owned());
}
#[test]
fn should_guess_mime_type_from_url() {
let url1 = "https://parity.io/parity";
let url2 = "https://parity.io/parity#content-type=image/png";
let url3 = "https://parity.io/parity#something&content-type=image/png";
let url4 = "https://parity.io/parity.png#content-type=image/jpeg";
let url5 = "https://parity.io/parity.png";
assert_eq!(guess_mime_type(url1), None);
assert_eq!(guess_mime_type(url2), Some(mime::IMAGE_PNG));
assert_eq!(guess_mime_type(url3), Some(mime::IMAGE_PNG));
assert_eq!(guess_mime_type(url4), Some(mime::IMAGE_JPEG));
assert_eq!(guess_mime_type(url5), Some(mime::IMAGE_PNG));
}
}