forked from
microcosm.blue/microcosm-rs
Constellation, Spacedust, Slingshot, UFOs: atproto crates and services for microcosm
parse dids
"links" is all references, so blocks, follows, etc. which are just direct dids also need to be detected.
+166
-14
+2
-6
src/at_uri.rs
+2
-6
src/at_uri.rs
···
17
17
if !s.is_ascii() {
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return None;
19
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}
20
-
// // A-Za-z0-9 . - _ ~
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-
// if !s.chars().all(|c| matches!(c, 'A'..='Z' | 'a'..='z' | '0'..='9' | '.' | '-' | '_' | '~')) {
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-
// return None
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-
// }
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20
25
21
// Maximum overall length is 8 kilobytes (which may be shortened in the future)
26
22
if s.len() > (8 * 2_usize.pow(10)) {
···
59
55
60
56
// The URI scheme is `at`, and an authority part preceded with double slashes is always
61
57
// required, so the URI always starts at://
62
-
// -> the spec doesn't explicitly say, but it seems like uri schemes are case-insensitive
58
+
// -> the spec doesn't explicitly say, but uri schemes can be case-insensitive?
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59
let (proto, rest) = s.split_at_checked(5)?;
64
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if !proto.eq_ignore_ascii_case("at://") {
65
61
return None;
···
225
221
(
226
222
"at://bad-example.com/a/../b",
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Some("at://bad-example.com/b"),
228
-
"paths have traversals resolved (oof)",
224
+
"paths have traversals resolved (oof)", // reminder to self: we are normalizing, not sanitizing
229
225
),
230
226
(
231
227
"at://bad-example.com/../",
+152
src/did.rs
+152
src/did.rs
···
1
+
/// see https://atproto.com/specs/did#at-protocol-did-identifier-syntax
2
+
/// this parser is intentinonally lax: it should accept all valid DIDs, and
3
+
/// may accept some invalid DIDs.
4
+
///
5
+
/// at the moment this implementation might also be quite bad and incomplete
6
+
pub fn parse_did(s: &str) -> Option<String> {
7
+
// for now, just working through the rules laid out in the docs in order,
8
+
// without much regard for efficiency for now.
9
+
10
+
// The entire URI is made up of a subset of ASCII, containing letters (A-Z, a-z),
11
+
// digits (0-9), period, underscore, colon, percent sign, or hyphen (._:%-)
12
+
if !s
13
+
.chars()
14
+
.all(|c| matches!(c, 'A'..='Z' | 'a'..='z' | '0'..='9' | '.' | '_' | ':' | '%' | '-'))
15
+
{
16
+
return None;
17
+
}
18
+
19
+
// The URI is case-sensitive
20
+
// -> (nothing to check)
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+
22
+
// The URI starts with lowercase `did:`
23
+
let unprefixed = s.strip_prefix("did:")?;
24
+
25
+
// The method segment is one or more lowercase letters (a-z), followed by :
26
+
let (method, identifier) = unprefixed.split_once(':')?;
27
+
if !method.chars().all(|c| c.is_ascii_lowercase()) {
28
+
return None;
29
+
}
30
+
31
+
// The remainder of the URI (the identifier) may contain any of the above-allowed
32
+
// ASCII characters, except for percent-sign (%)
33
+
// -> ok, ugh, gotta know our encoding context for this
34
+
35
+
// The URI (and thus the remaining identifier) may not end in ':'.
36
+
if identifier.ends_with(':') {
37
+
return None;
38
+
}
39
+
40
+
// Percent-sign (%) is used for "percent encoding" in the identifier section, and
41
+
// must always be followed by two hex characters
42
+
// -> again incoding context (bleh)
43
+
44
+
// Query (?) and fragment (#) sections are allowed in DID URIs, but not in DID
45
+
// identifiers. In the context of atproto, the query and fragment parts are not
46
+
// allowed.
47
+
// -> disallow here -- the uri decoder should already split them out first.
48
+
49
+
// DID identifiers do not generally have a maximum length restriction, but in the
50
+
// context of atproto, there is an initial hard limit of 2 KB.
51
+
// -> we're in atproto, so sure, let's enforce it. (would be sensible to do this
52
+
// -> first but we're following doc order)
53
+
if s.len() > (2 * 2_usize.pow(10)) {
54
+
return None;
55
+
}
56
+
57
+
// -> it's not actually written in the spec, but by example in the spec, the
58
+
// -> identifier cannot be empty
59
+
if identifier.is_empty() {
60
+
return None;
61
+
}
62
+
63
+
Some(s.to_string())
64
+
// the only normalization we might want would be percent-decoding, but we
65
+
// probably leave that to the uri decoder
66
+
}
67
+
68
+
#[cfg(test)]
69
+
mod tests {
70
+
use super::*;
71
+
72
+
#[test]
73
+
fn test_did_parse() {
74
+
for (case, expected, detail) in vec![
75
+
("", None, "empty str"),
76
+
(" ", None, "whitespace str"),
77
+
("z", None, "not a did"),
78
+
("did:plc", None, "no identifier separator colon"),
79
+
("did:plc:", None, "missing identifier"),
80
+
(
81
+
"did:web:bad-example.com",
82
+
Some("did:web:bad-example.com"),
83
+
"web did",
84
+
),
85
+
(
86
+
"did:plc:hdhoaan3xa3jiuq4fg4mefid",
87
+
Some("did:plc:hdhoaan3xa3jiuq4fg4mefid"),
88
+
"plc did",
89
+
),
90
+
(
91
+
"DID:plc:hdhoaan3xa3jiuq4fg4mefid",
92
+
None,
93
+
"'did:' prefix must be lowercase",
94
+
),
95
+
(
96
+
"did:ok:z",
97
+
Some("did:ok:z"),
98
+
"unknown did methods are allowed",
99
+
),
100
+
("did:BAD:z", None, "non-lowercase methods are not allowed"),
101
+
("did:bad:z$z", None, "invalid chars are not allowed"),
102
+
(
103
+
"did:ok:z:z",
104
+
Some("did:ok:z:z"),
105
+
"colons are allowed in identifier",
106
+
),
107
+
("did:bad:z:", None, "colons not are allowed at the end"),
108
+
("did:bad:z?q=y", None, "queries are not allowed in atproto"),
109
+
("did:bad:z#a", None, "anchors are not allowed in atproto"),
110
+
] {
111
+
assert_eq!(parse_did(case), expected.map(|s| s.to_string()), "{detail}");
112
+
}
113
+
}
114
+
115
+
#[test]
116
+
fn test_doc_exmples_atproto() {
117
+
// https://atproto.com/specs/did#at-protocol-did-identifier-syntax
118
+
for case in vec!["did:plc:z72i7hdynmk6r22z27h6tvur", "did:web:blueskyweb.xyz"] {
119
+
assert!(parse_did(case).is_some(), "should pass: {case}")
120
+
}
121
+
}
122
+
123
+
#[test]
124
+
fn test_doc_exmples_lexicon() {
125
+
// https://atproto.com/specs/did#at-protocol-did-identifier-syntax
126
+
for case in vec![
127
+
"did:method:val:two",
128
+
"did:m:v",
129
+
"did:method::::val",
130
+
"did:method:-:_:.",
131
+
"did:key:zQ3shZc2QzApp2oymGvQbzP8eKheVshBHbU4ZYjeXqwSKEn6N",
132
+
] {
133
+
assert!(parse_did(case).is_some(), "should pass: {case}")
134
+
}
135
+
}
136
+
137
+
#[test]
138
+
fn test_doc_exmples_invalid() {
139
+
// https://atproto.com/specs/did#at-protocol-did-identifier-syntax
140
+
for case in vec![
141
+
"did:METHOD:val",
142
+
"did:m123:val",
143
+
"DID:method:val",
144
+
"did:method:",
145
+
"did:method:val/two",
146
+
"did:method:val?two",
147
+
"did:method:val#two",
148
+
] {
149
+
assert!(parse_did(case).is_none(), "should fail: {case}")
150
+
}
151
+
}
152
+
}
+12
-8
src/lib.rs
+12
-8
src/lib.rs
···
1
1
use fluent_uri::Uri;
2
2
3
3
pub mod at_uri;
4
+
pub mod did;
4
5
5
6
#[derive(Debug, PartialEq)]
6
7
pub enum Link {
7
8
AtUri(String),
8
9
Uri(String),
9
-
}
10
-
11
-
// normalizing is a bit opinionated but ehhh
12
-
pub fn parse_at_uri(s: &str) -> Option<String> {
13
-
at_uri::parse_at_uri(s)
10
+
Did(String),
14
11
}
15
12
16
13
// normalizing is a bit opinionated but eh
···
19
16
}
20
17
21
18
pub fn parse_any(s: &str) -> Option<Link> {
22
-
parse_at_uri(s)
23
-
.map(Link::AtUri)
24
-
.or_else(|| parse_uri(s).map(Link::Uri))
19
+
at_uri::parse_at_uri(s).map(Link::AtUri).or_else(|| {
20
+
did::parse_did(s)
21
+
.map(Link::Did)
22
+
.or_else(|| parse_uri(s).map(Link::Uri))
23
+
})
25
24
}
26
25
27
26
#[cfg(test)]
···
60
59
"at://did:plc:44ybard66vv44zksje25o7dz/app.bsky.feed.post/3jwdwj2ctlk26".into()
61
60
)),
62
61
);
62
+
63
+
assert_eq!(
64
+
parse_any("did:plc:44ybard66vv44zksje25o7dz"),
65
+
Some(Link::Did("did:plc:44ybard66vv44zksje25o7dz".into()))
66
+
)
63
67
}
64
68
}