glean_core/metrics/
url.rs

1// This Source Code Form is subject to the terms of the Mozilla Public
2// License, v. 2.0. If a copy of the MPL was not distributed with this
3// file, You can obtain one at https://mozilla.org/MPL/2.0/.
4
5use std::sync::Arc;
6
7use crate::common_metric_data::CommonMetricDataInternal;
8use crate::error_recording::{record_error, test_get_num_recorded_errors, ErrorType};
9use crate::metrics::Metric;
10use crate::metrics::MetricType;
11use crate::storage::StorageManager;
12use crate::util::truncate_string_at_boundary_with_error;
13use crate::Glean;
14use crate::{CommonMetricData, TestGetValue};
15
16// The maximum number of characters a URL Metric may have, before encoding.
17const MAX_URL_LENGTH: usize = 8192;
18
19/// A URL metric.
20///
21/// Record an Unicode string value a URL content.
22/// The URL is length-limited to `MAX_URL_LENGTH` bytes.
23#[derive(Clone, Debug)]
24pub struct UrlMetric {
25    meta: Arc<CommonMetricDataInternal>,
26}
27
28impl MetricType for UrlMetric {
29    fn meta(&self) -> &CommonMetricDataInternal {
30        &self.meta
31    }
32}
33
34// IMPORTANT:
35//
36// When changing this implementation, make sure all the operations are
37// also declared in the related trait in `../traits/`.
38impl UrlMetric {
39    /// Creates a new string metric.
40    pub fn new(meta: CommonMetricData) -> Self {
41        Self {
42            meta: Arc::new(meta.into()),
43        }
44    }
45
46    fn is_valid_url_scheme(&self, value: String) -> bool {
47        let mut splits = value.split(':');
48        if let Some(scheme) = splits.next() {
49            if scheme.is_empty() {
50                return false;
51            }
52            let mut chars = scheme.chars();
53            // The list of characters allowed in the scheme is on
54            // the spec here: https://url.spec.whatwg.org/#url-scheme-string
55            return chars.next().unwrap().is_ascii_alphabetic()
56                && chars.all(|c| c.is_ascii_alphanumeric() || ['+', '-', '.'].contains(&c));
57        }
58
59        // No ':' found, this is not valid :)
60        false
61    }
62
63    /// Sets to the specified stringified URL.
64    ///
65    /// # Arguments
66    ///
67    /// * `value` - The stringified URL to set the metric to.
68    ///
69    /// ## Notes
70    ///
71    /// Truncates the value if it is longer than `MAX_URL_LENGTH` bytes and logs an error.
72    pub fn set<S: Into<String>>(&self, value: S) {
73        let value = value.into();
74        let metric = self.clone();
75        crate::launch_with_glean(move |glean| metric.set_sync(glean, value))
76    }
77
78    /// Sets to the specified stringified URL synchronously.
79    #[doc(hidden)]
80    pub fn set_sync<S: Into<String>>(&self, glean: &Glean, value: S) {
81        if !self.should_record(glean) {
82            return;
83        }
84
85        let s = truncate_string_at_boundary_with_error(glean, &self.meta, value, MAX_URL_LENGTH);
86
87        if s.starts_with("data:") {
88            record_error(
89                glean,
90                &self.meta,
91                ErrorType::InvalidValue,
92                "URL metric does not support data URLs.",
93                None,
94            );
95            return;
96        }
97
98        if !self.is_valid_url_scheme(s.clone()) {
99            let msg = format!("\"{}\" does not start with a valid URL scheme.", s);
100            record_error(glean, &self.meta, ErrorType::InvalidValue, msg, None);
101            return;
102        }
103
104        let value = Metric::Url(s);
105        glean.storage().record(glean, &self.meta, &value)
106    }
107
108    #[doc(hidden)]
109    pub(crate) fn get_value<'a, S: Into<Option<&'a str>>>(
110        &self,
111        glean: &Glean,
112        ping_name: S,
113    ) -> Option<String> {
114        let queried_ping_name = ping_name
115            .into()
116            .unwrap_or_else(|| &self.meta().inner.send_in_pings[0]);
117
118        match StorageManager.snapshot_metric(
119            glean.storage(),
120            queried_ping_name,
121            &self.meta.identifier(glean),
122            self.meta.inner.lifetime,
123        ) {
124            Some(Metric::Url(s)) => Some(s),
125            _ => None,
126        }
127    }
128
129    /// **Exported for test purposes.**
130    ///
131    /// Gets the number of recorded errors for the given metric and error type.
132    ///
133    /// # Arguments
134    ///
135    /// * `error` - The type of error
136    ///
137    /// # Returns
138    ///
139    /// The number of errors reported.
140    pub fn test_get_num_recorded_errors(&self, error: ErrorType) -> i32 {
141        crate::block_on_dispatcher();
142
143        crate::core::with_glean(|glean| {
144            test_get_num_recorded_errors(glean, self.meta(), error).unwrap_or(0)
145        })
146    }
147}
148
149impl TestGetValue for UrlMetric {
150    type Output = String;
151
152    /// **Test-only API (exported for FFI purposes).**
153    ///
154    /// Gets the currently stored value as a string.
155    ///
156    /// This doesn't clear the stored value.
157    ///
158    /// # Arguments
159    ///
160    /// * `ping_name` - the optional name of the ping to retrieve the metric
161    ///                 for. Defaults to the first value in `send_in_pings`.
162    ///
163    /// # Returns
164    ///
165    /// The stored value or `None` if nothing stored.
166    fn test_get_value(&self, ping_name: Option<String>) -> Option<String> {
167        crate::block_on_dispatcher();
168        crate::core::with_glean(|glean| self.get_value(glean, ping_name.as_deref()))
169    }
170}
171
172#[cfg(test)]
173mod test {
174    use super::*;
175    use crate::tests::new_glean;
176    use crate::Lifetime;
177
178    #[test]
179    fn payload_is_correct() {
180        let (glean, _t) = new_glean(None);
181
182        let metric = UrlMetric::new(CommonMetricData {
183            name: "url_metric".into(),
184            category: "test".into(),
185            send_in_pings: vec!["store1".into()],
186            lifetime: Lifetime::Application,
187            disabled: false,
188            dynamic_label: None,
189            in_session: false,
190        });
191
192        let sample_url = "glean://test".to_string();
193        metric.set_sync(&glean, sample_url.clone());
194        assert_eq!(sample_url, metric.get_value(&glean, "store1").unwrap());
195    }
196
197    #[test]
198    fn does_not_record_url_exceeding_maximum_length() {
199        let (glean, _t) = new_glean(None);
200
201        let metric = UrlMetric::new(CommonMetricData {
202            name: "url_metric".into(),
203            category: "test".into(),
204            send_in_pings: vec!["store1".into()],
205            lifetime: Lifetime::Application,
206            disabled: false,
207            dynamic_label: None,
208            in_session: false,
209        });
210
211        // Whenever the URL is longer than our MAX_URL_LENGTH, we truncate the URL to the
212        // MAX_URL_LENGTH.
213        //
214        // This 8-character string was chosen so we could have an even number that is
215        // a divisor of our MAX_URL_LENGTH.
216        let long_path_base = "abcdefgh";
217
218        // Using 2000 creates a string > 16000 characters, well over MAX_URL_LENGTH.
219        let test_url = format!("glean://{}", long_path_base.repeat(2000));
220        metric.set_sync(&glean, test_url);
221
222        // "glean://" is 8 characters
223        // "abcdefgh" (long_path_base) is 8 characters
224        // `long_path_base` is repeated 1023 times (8184)
225        // 8 + 8184 = 8192 (MAX_URL_LENGTH)
226        let expected = format!("glean://{}", long_path_base.repeat(1023));
227
228        assert_eq!(metric.get_value(&glean, "store1").unwrap(), expected);
229        assert_eq!(
230            1,
231            test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidOverflow)
232                .unwrap()
233        );
234    }
235
236    #[test]
237    fn does_not_record_data_urls() {
238        let (glean, _t) = new_glean(None);
239
240        let metric = UrlMetric::new(CommonMetricData {
241            name: "url_metric".into(),
242            category: "test".into(),
243            send_in_pings: vec!["store1".into()],
244            lifetime: Lifetime::Application,
245            disabled: false,
246            dynamic_label: None,
247            in_session: false,
248        });
249
250        let test_url = "data:application/json";
251        metric.set_sync(&glean, test_url);
252
253        assert!(metric.get_value(&glean, "store1").is_none());
254
255        assert_eq!(
256            1,
257            test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue).unwrap()
258        );
259    }
260
261    #[test]
262    fn url_validation_works_and_records_errors() {
263        let (glean, _t) = new_glean(None);
264
265        let metric = UrlMetric::new(CommonMetricData {
266            name: "url_metric".into(),
267            category: "test".into(),
268            send_in_pings: vec!["store1".into()],
269            lifetime: Lifetime::Application,
270            disabled: false,
271            dynamic_label: None,
272            in_session: false,
273        });
274
275        let incorrects = vec![
276            "",
277            // Scheme may only start with upper or lowercase ASCII alpha[^1] character.
278            // [1]: https://infra.spec.whatwg.org/#ascii-alpha
279            "1glean://test",
280            "-glean://test",
281            // Scheme may only have ASCII alphanumeric characters or the `-`, `.`, `+` characters.
282            "шеллы://test",
283            "g!lean://test",
284            "g=lean://test",
285            // Scheme must be followed by `:` character.
286            "glean//test",
287        ];
288
289        let corrects = vec![
290            // The minimum URL
291            "g:",
292            // Empty body is fine
293            "glean://",
294            // "//" is actually not even necessary
295            "glean:",
296            "glean:test",
297            "glean:test.com",
298            // Scheme may only have ASCII alphanumeric characters or the `-`, `.`, `+` characters.
299            "g-lean://test",
300            "g+lean://test",
301            "g.lean://test",
302            // Query parameters are fine
303            "glean://test?hello=world",
304            // Finally, some actual real world URLs
305            "https://infra.spec.whatwg.org/#ascii-alpha",
306            "https://infra.spec.whatwg.org/#ascii-alpha?test=for-glean",
307        ];
308
309        for incorrect in incorrects.clone().into_iter() {
310            metric.set_sync(&glean, incorrect);
311            assert!(metric.get_value(&glean, "store1").is_none());
312        }
313
314        assert_eq!(
315            incorrects.len(),
316            test_get_num_recorded_errors(&glean, metric.meta(), ErrorType::InvalidValue).unwrap()
317                as usize
318        );
319
320        for correct in corrects.into_iter() {
321            metric.set_sync(&glean, correct);
322            assert_eq!(metric.get_value(&glean, "store1").unwrap(), correct);
323        }
324    }
325}
glean_core/metrics/url.rs

glean_core/metrics/
url.rs
