freeswitch_types/
headers.rs

1//! Typed event header names for FreeSWITCH ESL events.
2
3/// Error returned when parsing an unrecognized event header name.
4#[derive(Debug, Clone, PartialEq, Eq)]
5pub struct ParseEventHeaderError(pub String);
6
7impl std::fmt::Display for ParseEventHeaderError {
8    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
9        write!(f, "unknown event header: {}", self.0)
10    }
11}
12
13impl std::error::Error for ParseEventHeaderError {}
14
15sip_header::define_header_enum! {
16    error_type: ParseEventHeaderError,
17    /// Top-level header names that appear in FreeSWITCH ESL events.
18    ///
19    /// These are the headers on the parsed event itself (not protocol framing
20    /// headers like `Content-Type`). Use with [`EslEvent::header()`](crate::EslEvent::header) for
21    /// type-safe lookups.
22    pub enum EventHeader {
23        EventName => "Event-Name",
24        EventSubclass => "Event-Subclass",
25        UniqueId => "Unique-ID",
26        CallerUniqueId => "Caller-Unique-ID",
27        OtherLegUniqueId => "Other-Leg-Unique-ID",
28        ChannelCallUuid => "Channel-Call-UUID",
29        JobUuid => "Job-UUID",
30        ChannelName => "Channel-Name",
31        ChannelState => "Channel-State",
32        ChannelStateNumber => "Channel-State-Number",
33        ChannelCallState => "Channel-Call-State",
34        AnswerState => "Answer-State",
35        CallDirection => "Call-Direction",
36        HangupCause => "Hangup-Cause",
37        CallerCallerIdName => "Caller-Caller-ID-Name",
38        CallerCallerIdNumber => "Caller-Caller-ID-Number",
39        CallerOrigCallerIdName => "Caller-Orig-Caller-ID-Name",
40        CallerOrigCallerIdNumber => "Caller-Orig-Caller-ID-Number",
41        CallerCalleeIdName => "Caller-Callee-ID-Name",
42        CallerCalleeIdNumber => "Caller-Callee-ID-Number",
43        CallerDestinationNumber => "Caller-Destination-Number",
44        CallerContext => "Caller-Context",
45        CallerDirection => "Caller-Direction",
46        CallerNetworkAddr => "Caller-Network-Addr",
47        CoreUuid => "Core-UUID",
48        DtmfDigit => "DTMF-Digit",
49        Priority => "priority",
50        LogLevel => "Log-Level",
51        /// SIP NOTIFY body content (JSON payload from `NOTIFY_IN` events).
52        PlData => "pl_data",
53        /// SIP event package name from `NOTIFY_IN` events (e.g. `emergency-AbandonedCall`).
54        SipEvent => "event",
55        /// SIP content type from `NOTIFY_IN` events.
56        SipContentType => "sip_content_type",
57        /// Gateway that received the SIP NOTIFY.
58        GatewayName => "gateway_name",
59
60        // --- Codec (from switch_channel_event_set_data / switch_core_codec.c) ---
61        // Audio read
62        ChannelReadCodecName => "Channel-Read-Codec-Name",
63        ChannelReadCodecRate => "Channel-Read-Codec-Rate",
64        ChannelReadCodecBitRate => "Channel-Read-Codec-Bit-Rate",
65        /// Only present when actual_samples_per_second != samples_per_second.
66        ChannelReportedReadCodecRate => "Channel-Reported-Read-Codec-Rate",
67        // Audio write
68        ChannelWriteCodecName => "Channel-Write-Codec-Name",
69        ChannelWriteCodecRate => "Channel-Write-Codec-Rate",
70        ChannelWriteCodecBitRate => "Channel-Write-Codec-Bit-Rate",
71        /// Only present when actual_samples_per_second != samples_per_second.
72        ChannelReportedWriteCodecRate => "Channel-Reported-Write-Codec-Rate",
73        // Video read/write
74        ChannelVideoReadCodecName => "Channel-Video-Read-Codec-Name",
75        ChannelVideoReadCodecRate => "Channel-Video-Read-Codec-Rate",
76        ChannelVideoWriteCodecName => "Channel-Video-Write-Codec-Name",
77        ChannelVideoWriteCodecRate => "Channel-Video-Write-Codec-Rate",
78        /// Active session count from `HEARTBEAT` events.
79        SessionCount => "Session-Count",
80        FreeswitchHostname => "FreeSWITCH-Hostname",
81        FreeswitchSwitchname => "FreeSWITCH-Switchname",
82        FreeswitchIpv4 => "FreeSWITCH-IPv4",
83        FreeswitchIpv6 => "FreeSWITCH-IPv6",
84        FreeswitchVersion => "FreeSWITCH-Version",
85        FreeswitchDomain => "FreeSWITCH-Domain",
86        FreeswitchUser => "FreeSWITCH-User",
87    }
88}
89
90/// Normalize a header key to its canonical form for case-insensitive storage.
91///
92/// FreeSWITCH's C ESL uses case-insensitive header lookups (`strcasecmp`), but
93/// stores header names verbatim. Multiple C code paths emit the same logical
94/// header with different casing (e.g. `switch_channel.c` sends `Unique-ID`
95/// while `switch_event.c` sends `unique-id`). This function normalizes keys
96/// so that both resolve to the same `HashMap` entry.
97///
98/// **Strategy:**
99/// 1. Known [`EventHeader`] variants are matched first (case-insensitive) and
100///    returned in their canonical wire form (e.g. `unique-id` → `Unique-ID`).
101/// 2. Unknown keys containing underscores are returned **unchanged** — these
102///    are channel variables (`variable_*`) or `sip_h_*` passthrough headers
103///    where the suffix preserves the original SIP header casing.
104/// 3. Unknown dash-separated keys are Title-Cased to match FreeSWITCH's
105///    dominant convention for event and framing headers.
106pub fn normalize_header_key(raw: &str) -> String {
107    if let Ok(eh) = raw.parse::<EventHeader>() {
108        return eh
109            .as_str()
110            .to_string();
111    }
112    if raw.contains('_') {
113        raw.to_string()
114    } else {
115        title_case_dashes(raw)
116    }
117}
118
119fn title_case_dashes(s: &str) -> String {
120    let mut result = String::with_capacity(s.len());
121    let mut capitalize_next = true;
122    for c in s.chars() {
123        if c == '-' {
124            result.push('-');
125            capitalize_next = true;
126        } else if capitalize_next {
127            result.push(c.to_ascii_uppercase());
128            capitalize_next = false;
129        } else {
130            result.push(c.to_ascii_lowercase());
131        }
132    }
133    result
134}
135
136#[cfg(test)]
137mod tests {
138    use super::*;
139
140    #[test]
141    fn display_round_trip() {
142        assert_eq!(EventHeader::UniqueId.to_string(), "Unique-ID");
143        assert_eq!(
144            EventHeader::ChannelCallState.to_string(),
145            "Channel-Call-State"
146        );
147        assert_eq!(
148            EventHeader::CallerCallerIdName.to_string(),
149            "Caller-Caller-ID-Name"
150        );
151        assert_eq!(EventHeader::Priority.to_string(), "priority");
152    }
153
154    #[test]
155    fn as_ref_str() {
156        let h: &str = EventHeader::UniqueId.as_ref();
157        assert_eq!(h, "Unique-ID");
158    }
159
160    #[test]
161    fn from_str_case_insensitive() {
162        assert_eq!(
163            "unique-id".parse::<EventHeader>(),
164            Ok(EventHeader::UniqueId)
165        );
166        assert_eq!(
167            "UNIQUE-ID".parse::<EventHeader>(),
168            Ok(EventHeader::UniqueId)
169        );
170        assert_eq!(
171            "Unique-ID".parse::<EventHeader>(),
172            Ok(EventHeader::UniqueId)
173        );
174        assert_eq!(
175            "channel-call-state".parse::<EventHeader>(),
176            Ok(EventHeader::ChannelCallState)
177        );
178    }
179
180    #[test]
181    fn from_str_unknown() {
182        let err = "X-Custom-Not-In-Enum".parse::<EventHeader>();
183        assert!(err.is_err());
184        assert_eq!(
185            err.unwrap_err()
186                .to_string(),
187            "unknown event header: X-Custom-Not-In-Enum"
188        );
189    }
190
191    // --- normalize_header_key tests ---
192    // FreeSWITCH C ESL uses strcasecmp for header lookups but stores names
193    // verbatim. Multiple C code paths emit the same logical header with
194    // different casing (switch_channel.c Title-Case vs switch_event.c lowercase
195    // vs switch_core_codec.c mixed). normalize_header_key canonicalizes keys
196    // so they collapse to a single HashMap entry.
197
198    #[test]
199    fn normalize_known_enum_variants_return_canonical_form() {
200        // EventHeader::from_str is case-insensitive; canonical as_str() is returned
201        assert_eq!(normalize_header_key("unique-id"), "Unique-ID");
202        assert_eq!(normalize_header_key("UNIQUE-ID"), "Unique-ID");
203        assert_eq!(normalize_header_key("Unique-ID"), "Unique-ID");
204        assert_eq!(normalize_header_key("dtmf-digit"), "DTMF-Digit");
205        assert_eq!(normalize_header_key("DTMF-DIGIT"), "DTMF-Digit");
206        assert_eq!(
207            normalize_header_key("channel-call-uuid"),
208            "Channel-Call-UUID"
209        );
210        assert_eq!(normalize_header_key("event-name"), "Event-Name");
211    }
212
213    #[test]
214    fn normalize_known_underscore_variants_return_canonical_form() {
215        // Headers whose canonical form contains underscores
216        assert_eq!(normalize_header_key("priority"), "priority");
217        assert_eq!(normalize_header_key("PRIORITY"), "priority");
218        assert_eq!(normalize_header_key("pl_data"), "pl_data");
219        assert_eq!(normalize_header_key("PL_DATA"), "pl_data");
220        assert_eq!(normalize_header_key("sip_content_type"), "sip_content_type");
221        assert_eq!(normalize_header_key("gateway_name"), "gateway_name");
222        assert_eq!(normalize_header_key("event"), "event");
223        assert_eq!(normalize_header_key("EVENT"), "event");
224    }
225
226    #[test]
227    fn normalize_codec_headers_from_switch_core_codec() {
228        // switch_core_codec.c sends lowercase, switch_channel_event_set_data sends Title-Case
229        // Both must normalize to the canonical EventHeader form
230        assert_eq!(
231            normalize_header_key("channel-read-codec-bit-rate"),
232            "Channel-Read-Codec-Bit-Rate"
233        );
234        assert_eq!(
235            normalize_header_key("Channel-Read-Codec-Bit-Rate"),
236            "Channel-Read-Codec-Bit-Rate"
237        );
238        // switch_core_codec.c mixed case for write: "Channel-Write-codec-bit-rate"
239        assert_eq!(
240            normalize_header_key("Channel-Write-codec-bit-rate"),
241            "Channel-Write-Codec-Bit-Rate"
242        );
243        assert_eq!(
244            normalize_header_key("channel-video-read-codec-name"),
245            "Channel-Video-Read-Codec-Name"
246        );
247    }
248
249    #[test]
250    fn normalize_unknown_underscore_keys_passthrough() {
251        // Channel variables and sip_h_* passthrough preserve original casing
252        assert_eq!(
253            normalize_header_key("variable_sip_call_id"),
254            "variable_sip_call_id"
255        );
256        assert_eq!(
257            normalize_header_key("variable_sip_h_X-My-CUSTOM-Header"),
258            "variable_sip_h_X-My-CUSTOM-Header"
259        );
260        assert_eq!(
261            normalize_header_key("variable_sip_h_Diversion"),
262            "variable_sip_h_Diversion"
263        );
264    }
265
266    #[test]
267    fn normalize_unknown_dash_keys_title_case() {
268        // Framing and unknown event headers get Title-Cased
269        assert_eq!(normalize_header_key("content-type"), "Content-Type");
270        assert_eq!(normalize_header_key("Content-Type"), "Content-Type");
271        assert_eq!(normalize_header_key("CONTENT-TYPE"), "Content-Type");
272        assert_eq!(normalize_header_key("x-custom-header"), "X-Custom-Header");
273        assert_eq!(
274            normalize_header_key("Content-Disposition"),
275            "Content-Disposition"
276        );
277        assert_eq!(normalize_header_key("reply-text"), "Reply-Text");
278    }
279
280    #[test]
281    fn normalize_idempotent_for_all_enum_variants() {
282        // Normalizing an already-canonical wire string must return it unchanged
283        let variants = [
284            EventHeader::EventName,
285            EventHeader::UniqueId,
286            EventHeader::ChannelCallUuid,
287            EventHeader::DtmfDigit,
288            EventHeader::Priority,
289            EventHeader::PlData,
290            EventHeader::SipEvent,
291            EventHeader::GatewayName,
292            EventHeader::SipContentType,
293            EventHeader::ChannelReadCodecBitRate,
294            EventHeader::ChannelVideoWriteCodecRate,
295            EventHeader::LogLevel,
296        ];
297        for v in variants {
298            let canonical = v.as_str();
299            assert_eq!(
300                normalize_header_key(canonical),
301                canonical,
302                "normalization not idempotent for {canonical}"
303            );
304        }
305    }
306
307    #[test]
308    fn from_str_round_trip_all_variants() {
309        let variants = [
310            EventHeader::EventName,
311            EventHeader::EventSubclass,
312            EventHeader::UniqueId,
313            EventHeader::CallerUniqueId,
314            EventHeader::OtherLegUniqueId,
315            EventHeader::ChannelCallUuid,
316            EventHeader::JobUuid,
317            EventHeader::ChannelName,
318            EventHeader::ChannelState,
319            EventHeader::ChannelStateNumber,
320            EventHeader::ChannelCallState,
321            EventHeader::AnswerState,
322            EventHeader::CallDirection,
323            EventHeader::HangupCause,
324            EventHeader::CallerCallerIdName,
325            EventHeader::CallerCallerIdNumber,
326            EventHeader::CallerOrigCallerIdName,
327            EventHeader::CallerOrigCallerIdNumber,
328            EventHeader::CallerCalleeIdName,
329            EventHeader::CallerCalleeIdNumber,
330            EventHeader::CallerDestinationNumber,
331            EventHeader::CallerContext,
332            EventHeader::CallerDirection,
333            EventHeader::CallerNetworkAddr,
334            EventHeader::CoreUuid,
335            EventHeader::DtmfDigit,
336            EventHeader::Priority,
337            EventHeader::LogLevel,
338            EventHeader::PlData,
339            EventHeader::SipEvent,
340            EventHeader::SipContentType,
341            EventHeader::GatewayName,
342            EventHeader::ChannelReadCodecName,
343            EventHeader::ChannelReadCodecRate,
344            EventHeader::ChannelReadCodecBitRate,
345            EventHeader::ChannelReportedReadCodecRate,
346            EventHeader::ChannelWriteCodecName,
347            EventHeader::ChannelWriteCodecRate,
348            EventHeader::ChannelWriteCodecBitRate,
349            EventHeader::ChannelReportedWriteCodecRate,
350            EventHeader::ChannelVideoReadCodecName,
351            EventHeader::ChannelVideoReadCodecRate,
352            EventHeader::ChannelVideoWriteCodecName,
353            EventHeader::ChannelVideoWriteCodecRate,
354        ];
355        for v in variants {
356            let wire = v.to_string();
357            let parsed: EventHeader = wire
358                .parse()
359                .unwrap();
360            assert_eq!(parsed, v, "round-trip failed for {wire}");
361        }
362    }
363}
freeswitch_types/headers.rs

freeswitch_types/
headers.rs
