1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
|
//! Atward implements TVL's redirection service, living at
//! atward.tvl.fyi
//!
//! This service is designed to be added as a search engine to web
//! browsers and attempts to send users to useful locations based on
//! their search query (falling back to another search engine).
use regex::Regex;
use rouille::input::cookies;
use rouille::{Request, Response};
#[cfg(test)]
mod tests;
/// A query handler supported by atward. It consists of a pattern on
/// which to match and trigger the query, and a function to execute
/// that returns the target URL.
struct Handler {
/// Regular expression on which to match the query string.
pattern: Regex,
/// Function to construct the target URL. If the pattern matches,
/// this is invoked with the captured matches and the entire URI.
///
/// Returning `None` causes atward to fall through to the next
/// query (and eventually to the default search engine).
target: for<'s> fn(&Query, regex::Captures<'s>) -> Option<String>,
}
/// An Atward query supplied by a user.
#[derive(Debug, PartialEq)]
struct Query {
/// Query string itself.
query: String,
/// Should Sourcegraph be used instead of cgit?
cs: bool,
}
/// Helper function for setting a parameter based on a query
/// parameter.
fn query_setting(req: &Request, config: &mut bool, param: &str) {
match req.get_param(param) {
Some(s) if s == "true" => *config = true,
Some(s) if s == "false" => *config = false,
_ => {}
}
}
impl Query {
fn from_request(req: &Request) -> Option<Query> {
// First extract the actual search query ...
let mut query = match req.get_param("q") {
Some(query) => Query { query, cs: false },
None => return None,
};
// ... then apply settings to it. Settings in query parameters
// take precedence over cookies.
for cookie in cookies(req) {
match cookie {
("cs", "true") => {
query.cs = true;
}
_ => {}
}
}
query_setting(req, &mut query.cs, "cs");
Some(query)
}
}
#[cfg(test)]
impl From<&str> for Query {
fn from(query: &str) -> Query {
Query {
query: query.to_string(),
cs: false,
}
}
}
/// Create a URL to a file (and, optionally, specific line) in cgit.
fn cgit_url(path: &str) -> String {
if path.ends_with(".md") {
format!("https://code.tvl.fyi/about/{}", path)
} else {
format!("https://code.tvl.fyi/tree/{}", path)
}
}
/// Create a URL to a path in Sourcegraph.
fn sourcegraph_path_url(path: &str) -> String {
format!("https://cs.tvl.fyi/depot/-/tree/{}", path)
}
/// Definition of all supported query handlers in atward.
fn handlers() -> Vec<Handler> {
vec![
// Bug IDs (e.g. b/123)
Handler {
pattern: Regex::new("^b/(?P<bug>\\d+)$").unwrap(),
target: |_, captures| Some(format!("https://b.tvl.fyi/{}", &captures["bug"])),
},
// Changelists (e.g. cl/42)
Handler {
pattern: Regex::new("^cl/(?P<cl>\\d+)$").unwrap(),
target: |_, captures| Some(format!("https://cl.tvl.fyi/{}", &captures["cl"])),
},
// Non-parameterised short hostnames should redirect to $host.tvl.fyi
Handler {
pattern: Regex::new("^(?P<host>b|cl|cs|code|at|todo)$").unwrap(),
target: |_, captures| Some(format!("https://{}.tvl.fyi/", &captures["host"])),
},
// Depot revisions (e.g. r/3002)
Handler {
pattern: Regex::new("^r/(?P<rev>\\d+)$").unwrap(),
target: |_, captures| {
Some(format!(
"https://code.tvl.fyi/commit/?id=refs/r/{}",
&captures["rev"]
))
},
},
// Depot paths (e.g. //web/atward or //ops/nixos/whitby/default.nix)
// TODO(tazjin): Add support for specifying lines in a query parameter
Handler {
pattern: Regex::new("^//(?P<path>[a-zA-Z].*)?$").unwrap(),
target: |query, captures| {
// Pass an empty string if the path is missing, to
// redirect to the depot root.
let path = captures.name("path").map(|m| m.as_str()).unwrap_or("");
if query.cs {
Some(sourcegraph_path_url(path))
} else {
Some(cgit_url(path))
}
},
},
]
}
/// Attempt to match against all known query types, and return the
/// destination URL if one is found.
fn dispatch(handlers: &[Handler], query: &Query) -> Option<String> {
for handler in handlers {
if let Some(captures) = handler.pattern.captures(&query.query) {
if let Some(destination) = (handler.target)(query, captures) {
return Some(destination);
}
}
}
None
}
/// Return the opensearch.xml file which is required for adding atward
/// as a search engine in Firefox.
fn opensearch() -> Response {
Response::text(include_str!("opensearch.xml"))
.with_unique_header("Content-Type", "application/opensearchdescription+xml")
}
/// Render the atward index page which gives users some information
/// about how to use the service.
fn index() -> Response {
Response::html(include_str!(env!("ATWARD_INDEX_HTML")))
}
/// Render the fallback page which informs users that their query is
/// unsupported.
fn fallback() -> Response {
Response::text("error for emphasis that i am angery and the query whimchst i angery atward")
.with_status_code(404)
}
fn main() {
let queries = handlers();
let address = std::env::var("ATWARD_LISTEN_ADDRESS")
.expect("ATWARD_LISTEN_ADDRESS environment variable must be set");
rouille::start_server(&address, move |request| {
rouille::log(&request, std::io::stderr(), || {
if request.url() == "/opensearch.xml" {
return opensearch();
}
let query = match Query::from_request(&request) {
Some(q) => q,
None => return index(),
};
match dispatch(&queries, &query) {
None => fallback(),
Some(destination) => Response::redirect_303(destination),
}
})
});
}
|
