title: HTTP/3 qlog event definitions docname: draft-ietf-quic-qlog-h3-events-latest category: std
ipr: trust200902 area: Transport workgroup: QUIC keyword: Internet-Draft
stand_alone: yes pi: [toc, docindent, sortrefs, symrefs, strict, compact, comments, inline]
ins: R. Marx
name: Robin Marx
org: Akamai
email: [email protected]
role: editor
- ins: L. Niccolini name: Luca Niccolini org: Meta email: [email protected] role: editor
- ins: M. Seemann name: Marten Seemann email: [email protected] role: editor
- ins: L. Pardue name: Lucas Pardue org: Cloudflare email: [email protected] role: editor
normative: RFC9110: display: HTTP
RFC9114: display: HTTP/3
QLOG-MAIN: I-D.ietf-quic-qlog-main-schema
QLOG-QUIC: I-D.ietf-quic-qlog-quic-events
informative:
--- abstract
This document defines a qlog event schema containing concrete events for the core HTTP/3 protocol and selected extensions.
--- note_Note_to_Readers
Note to RFC editor: Please remove this section before publication.
Feedback and discussion are welcome at https://github.com/quicwg/qlog. Readers are advised to refer to the "editor's draft" at that URL for an up-to-date version of this document.
Concrete examples of integrations of this schema in various programming languages can be found at https://github.com/quiclog/qlog/.
--- middle
This document defines a qlog event schema ({{Section 8 of QLOG-MAIN}}) containing concrete events for the core HTTP/3 protocol {{RFC9114}} and selected extensions ({{!EXTENDED-CONNECT=RFC9220}}, {{!H3_PRIORITIZATION=RFC9218}}, and {{!H3-DATAGRAM=RFC9297}}).
The event namespace with identifier http3
is defined; see {{schema-def}}. In
this namespace multiple events derive from the qlog abstract Event class
({{Section 7 of QLOG-MAIN}}), each extending the "data" field and defining
their "name" field values and semantics.
{{h3-events}} summarizes the name value of each event type that is defined in this specification. Some event data fields use complex data types. These are represented as enums or re-usable definitions, which are grouped together on the bottom of this document for clarity.
Name value | Importance | Definition |
---|---|---|
http3:parameters_set | Base | {{h3-parametersset}} |
http3:parameters_restored | Base | {{h3-parametersrestored}} |
http3:stream_type_set | Base | {{h3-streamtypeset}} |
http3:priority_updated | Base | {{h3-priorityupdated}} |
http3:frame_created | Core | {{h3-framecreated}} |
http3:frame_parsed | Core | {{h3-frameparsed}} |
http3:datagram_created | Base | {{h3-datagramcreated}} |
http3:datagram_parsed | Base | {{h3-datagramparsed}} |
http3:push_resolved | Extra | {{h3-pushresolved}} |
{: #h3-events title="HTTP/3 Events"} |
When any event from this document is included in a qlog trace, the "protocol_types" qlog array field MUST contain an entry with the value "HTTP/3":
$ProtocolType /= "HTTP/3"
{: #protocoltype-extension-h3 title="ProtocolType extension for HTTP/3"}
The events described in this document can be used with or without logging the related QUIC events defined in {{QLOG-QUIC}}. If used with QUIC events, the QUIC document takes precedence in terms of recommended filenames and trace separation setups.
If used without QUIC events, it is recommended that the implementation assign a globally unique identifier to each HTTP/3 connection. This ID can then be used as the value of the qlog "group_id" field, as well as the qlog filename or file identifier, potentially suffixed by the vantagepoint type (For example, abcd1234_server.qlog would contain the server-side trace of the connection with GUID abcd1234).
{::boilerplate bcp14-tagged}
The event and data structure definitions in ths document are expressed in the Concise Data Definition Language {{!CDDL=RFC8610}} and its extensions described in {{QLOG-MAIN}}.
The following fields from {{QLOG-MAIN}} are imported and used: name, namespace, type, data, group_id, protocol_types, importance, RawInfo, and time-related fields.
As is the case for {{QLOG-MAIN}}, the qlog schema definitions in this document are intentionally agnostic to serialization formats. The choice of format is an implementation decision.
This document describes how the core HTTP/3 protocol and selected extensions can
be expressed in qlog using a newly defined event schema. Per the requirements in
{{Section 8 of QLOG-MAIN}}, this document registers the http3
namespace. The
event schema URI is urn:ietf:params:qlog:events:http3
.
{:removeinrfc="true"}
Only implementations of the final, published RFC can use the events belonging to
the event schema with the URI urn:ietf:params:qlog:events:http3
. Until such an
RFC exists, implementations MUST NOT identify themselves using this URI.
Implementations of draft versions of the event schema MUST append the string
"-" and the corresponding draft number to the URI. For example, draft 07 of this
document is identified using the URI urn:ietf:params:qlog:events:http3-07
.
The namespace identifier itself is not affected by this requirement.
HTTP/3 events extend the $ProtocolEventData
extension point defined in
{{QLOG-MAIN}}. Additionally, they allow for direct extensibility by their use of
per-event extension points via the $$
CDDL "group socket" syntax, as also
described in {{QLOG-MAIN}}.
HTTP3EventData = HTTP3ParametersSet /
HTTP3ParametersRestored /
HTTP3StreamTypeSet /
HTTP3PriorityUpdated /
HTTP3FrameCreated /
HTTP3FrameParsed /
HTTP3DatagramCreated /
HTTP3DatagramParsed /
HTTP3PushResolved
$ProtocolEventData /= HTTP3EventData
{: #h3-events-def title="HTTP3EventData definition and ProtocolEventData extension"}
HTTP events are logged when a certain condition happens at the application layer, and there isn't always a one to one mapping between HTTP and QUIC events. The exchange of data between the HTTP and QUIC layer is logged via the "stream_data_moved" and "datagram_data_moved" events in {{QLOG-QUIC}}.
HTTP/3 frames are transmitted on QUIC streams, which allows them to span multiple QUIC packets. Some implementations might send a single large frame, rather than a sequence of smaller frames, in order to amortize frame header overhead. HTTP/3 frame headers are represented by the frame_created ({{h3-framecreated}}) and frame_parsed ({{h3-frameparsed}}) events. Subsequent frame payload data transfer is indicated by stream_data_moved events. Furthermore, stream_data_moved events can appear before frame_parsed events because implementations need to read data from a stream in order to parse the frame header.
The concrete HTTP/3 event types are further defined below, their type identifier is the heading name.
The parameters_set
event contains HTTP/3 and QPACK-level settings, mostly
those received from the HTTP/3 SETTINGS frame. It has Base importance level; see
{{Section 9.2 of QLOG-MAIN}}.
All these parameters are typically set once and never change. However, they
might be set at different times during the connection, therefore a qlog can have
multiple instances of parameters_set
with different fields set.
The "owner" field reflects how Settings are exchanged on a connection. Sent settings have the value "local" and received settings have the value "received".
HTTP3ParametersSet = {
? owner: Owner
; RFC9114
? max_field_section_size: uint64
; RFC9204
? max_table_capacity: uint64
? blocked_streams_count: uint64
; RFC9220 (SETTINGS_ENABLE_CONNECT_PROTOCOL)
? extended_connect: uint16
; RFC9297 (SETTINGS_H3_DATAGRAM)
? h3_datagram: uint16
; qlog-specific
; indicates whether this implementation waits for a SETTINGS
; frame before processing requests
? waits_for_settings: bool
* $$http3-parametersset-extension
}
{: #h3-parametersset-def title="HTTP3ParametersSet definition"}
The parameters_set
event can contain any number of unspecified fields. This
allows for representation of reserved settings (aka GREASE) or ad-hoc support
for extension settings that do not have a related qlog schema definition.
When using QUIC 0-RTT, HTTP/3 clients are expected to remember and reuse the
server's SETTINGs from the previous connection. The parameters_restored
event
is used to indicate which HTTP/3 settings were restored and to which values when
utilizing 0-RTT. It has Base importance level; see {{Section 9.2 of QLOG-MAIN}}.
HTTP3ParametersRestored = {
; RFC9114
? max_field_section_size: uint64
; RFC9204
? max_table_capacity: uint64
? blocked_streams_count: uint64
; RFC9220 (SETTINGS_ENABLE_CONNECT_PROTOCOL)
? extended_connect: uint16
; RFC9297 (SETTINGS_H3_DATAGRAM)
? h3_datagram: uint16
* $$http3-parametersrestored-extension
}
{: #h3-parametersrestored-def title="HTTP3ParametersRestored definition"}
The stream_type_set
event conveys when a HTTP/3 stream type becomes known; see
{{Sections 6.1 and 6.2 of RFC9114}}. It has Base importance level; see {{Section
9.2 of QLOG-MAIN}}.
Client bidirectional streams always have a stream_type value of "request". Server bidirectional streams have no defined use, although extensions could change that.
Unidirectional streams in either direction begin with with a variable-length integer type. Where the type is not known, the stream_type value of "unknown" type can be used and the value captured in the stream_type_bytes field; a numerical value without variable-length integer encoding.
The generic $HTTP3StreamType
is defined here as a CDDL "type socket" extension
point. It can be extended to support additional HTTP/3 stream types.
HTTP3StreamTypeSet = {
? owner: Owner
stream_id: uint64
stream_type: $HTTP3StreamType
; only when stream_type === "unknown"
? stream_type_bytes: uint64
; only when stream_type === "push"
? associated_push_id: uint64
* $$http3-streamtypeset-extension
}
$HTTP3StreamType /= "request" /
"control" /
"push" /
"reserved" /
"unknown" /
"qpack_encode" /
"qpack_decode"
{: #h3-streamtypeset-def title="HTTP3StreamTypeSet definition"}
Emitted when the priority of a request stream or push stream is initialized or updated through mechanisms defined in {{!RFC9218}}. For example, the priority can be updated through signals received from client and/or server (e.g., in HTTP/3 HEADERS or PRIORITY_UPDATE frames) or it can be changed or overridden due to local policies. The event has Base importance level; see {{Section 9.2 of QLOG-MAIN}}.
HTTP3PriorityUpdated = {
; if the prioritized element is a request stream
? stream_id: uint64
; if the prioritized element is a push stream
? push_id: uint64
? old: HTTP3Priority
new: HTTP3Priority
* $$http3-priorityupdated-extension
}
{: #h3-priorityupdated-def title="HTTP3PriorityUpdated definition"}
The frame_created
event is emitted when the HTTP/3 framing actually happens.
It has Core importance level; see {{Section 9.2 of QLOG-MAIN}}.
This event does not necessarily coincide with HTTP/3 data getting passed to the
QUIC layer. For that, see the stream_data_moved
event in {{QLOG-QUIC}}.
HTTP3FrameCreated = {
stream_id: uint64
? length: uint64
frame: $HTTP3Frame
? raw: RawInfo
* $$http3-framecreated-extension
}
{: #h3-framecreated-def title="HTTP3FrameCreated definition"}
The frame_parsed
event is emitted when the HTTP/3 frame is parsed. It has Core
importance level; see {{Section 9.2 of QLOG-MAIN}}.
This event is not necessarily the same as when the HTTP/3 data is actually
received on the QUIC layer. For that, see the stream_data_moved
event in
{{QLOG-QUIC}}.
HTTP3FrameParsed = {
stream_id: uint64
? length: uint64
frame: $HTTP3Frame
? raw: RawInfo
* $$h3-frameparsed-extension
}
{: #h3-frameparsed-def title="HTTP3FrameParsed definition"}
The datagram_created
event is emitted when an HTTP/3 Datagram is created (see
{{!RFC9297}}). It has Base importance level; see {{Section 9.2 of QLOG-MAIN}}.
This event does not necessarily coincide with the HTTP/3 Datagram getting passed
to the QUIC layer. For that, see the datagram_data_moved
event in
{{QLOG-QUIC}}.
HTTP3DatagramCreated = {
quarter_stream_id: uint64
? datagram: $HTTP3Datagram
? raw: RawInfo
* $$http3-datagramcreated-extension
}
{: #h3-datagramcreated-def title="HTTP3DatagramCreated definition"}
The datagram_parsed
event is emitted when the HTTP/3 Datagram is parsed (see
{{!RFC9297}}). It has Base importance level; see {{Section 9.2 of QLOG-MAIN}}.
This event is not necessarily the same as when the HTTP/3 Datagram is actually
received on the QUIC layer. For that, see the datagram_data_moved
event in
{{QLOG-QUIC}}.
HTTP3DatagramParsed = {
quarter_stream_id: uint64
? datagram: $HTTP3Datagram
? raw: RawInfo
* $$http3-datagramparsed-extension
}
{: #h3-datagramparsed-def title="HTTP3DatagramParsed definition"}
The push_resolved
event is emitted when a pushed resource ({{Section 4.6 of
RFC9114}}) is successfully claimed (used) or, conversely, abandoned (rejected)
by the application on top of HTTP/3 (e.g., the web browser). This event provides
additional context that can is aid debugging issues related to server push. It
has Extra importance level; see {{Section 9.2 of QLOG-MAIN}}.
HTTP3PushResolved = {
? push_id: uint64
; in case this is logged from a place that does not have access
; to the push_id
? stream_id: uint64
decision: HTTP3PushDecision
* $$http3-pushresolved-extension
}
HTTP3PushDecision = "claimed" /
"abandoned"
{: #h3-pushresolved-def title="HTTP3PushResolved definition"}
The following data type definitions can be used in HTTP/3 events.
Owner = "local" /
"remote"
{: #owner-def title="Owner definition"}
The generic $HTTP3Frame
is defined here as a CDDL "type socket" extension point.
It can be extended to support additional HTTP/3 frame types.
; The HTTP3Frame is any key-value map (e.g., JSON object)
$HTTP3Frame /= {
* text => any
}
{: #h3-frame-def title="HTTP3Frame type socket definition"}
The HTTP/3 frame types defined in this document are as follows:
HTTP3BaseFrames = HTTP3DataFrame /
HTTP3HeadersFrame /
HTTP3CancelPushFrame /
HTTP3SettingsFrame /
HTTP3PushPromiseFrame /
HTTP3GoawayFrame /
HTTP3MaxPushIDFrame /
HTTP3ReservedFrame /
HTTP3UnknownFrame
$HTTP3Frame /= HTTP3BaseFrames
{: #h3baseframe-def title="HTTP3BaseFrames definition"}
The generic $HTTP3Datagram
is defined here as a CDDL "type socket" extension
point. It can be extended to support additional HTTP/3 datagram types. This
document intentionally does not define any specific qlog schemas for specific
HTTP/3 Datagram types.
; The HTTP3Datagram is any key-value map (e.g., JSON object)
$HTTP3Datagram /= {
* text => any
}
{: #h3-datagram-def title="HTTP3Datagram type socket definition"}
HTTP3DataFrame = {
frame_type: "data"
? raw: RawInfo
}
{: #h3dataframe-def title="HTTP3DataFrame definition"}
The payload of an HTTP/3 HEADERS frame is the QPACK-encoding of an HTTP field
section; see {{Section 7.2.2 of RFC9114}}. HTTP3HeaderFrame
, in contrast,
contains the HTTP field section without QPACK encoding.
HTTP3HTTPField = {
? name: text
? name_bytes: hexstring
? value: text
? value_bytes: hexstring
}
{: #h3field-def title="HTTP3HTTPField definition"}
HTTP3HeadersFrame = {
frame_type: "headers"
headers: [* HTTP3HTTPField]
}
{: #h3-headersframe-def title="HTTP3HeadersFrame definition"}
For example, the HTTP field section
:path: /index.html
:method: GET
:authority: example.org
:scheme: https
would be represented in a JSON serialization as:
headers: [
{
"name": ":path",
"value": "/"
},
{
"name": ":method",
"value": "GET"
},
{
"name": ":authority",
"value": "example.org"
},
{
"name": ":scheme",
"value": "https"
}
]
{: #h3-headersframe-ex title="HTTP3HeadersFrame example"}
{{Section 4.2 of RFC9114}} and {{Section 5.1 of RFC9110}} define rules for the
characters used in HTTP field sections names and values. Characters outside the
range are invalid and result in the message being treated as malformed. It can
however be useful to also log these invalid HTTP fields. Characters in the
allowed range can be safely logged by the text type used in the name
and
value
fields of HTTP3HTTPField
. Characters outside the range are unsafe for the
text type and need to be logged using the name_bytes
and value_bytes
field.
An instance of HTTP3HTTPField
MUST include either the name
or name_bytes
field and MAY include both. An HTTP3HTTPField
MAY include a value
or
value_bytes
field or neither.
HTTP3CancelPushFrame = {
frame_type: "cancel_push"
push_id: uint64
}
{: #h3-cancelpushframe-def title="HTTP3CancelPushFrame definition"}
The settings field can contain zero or more entries. Each setting has a name field, which corresponds to Setting Name as defined (or as would be defined if registered) in the "HTTP/3 Settings" registry maintained at https://www.iana.org/assignments/http3-parameters.
An endpoint that receives unknown settings is not able to log a specific name.
Instead, the name value of "unknown" can be used and the value captured in the
name_bytes
field; a numerical value without variable-length integer encoding.
HTTP3SettingsFrame = {
frame_type: "settings"
settings: [* HTTP3Setting]
}
HTTP3Setting = {
? name: $HTTP3SettingsName
; only when name === "unknown"
? name_bytes: uint64
value: uint64
}
$HTTP3SettingsName /= "settings_qpack_max_table_capacity" /
"settings_max_field_section_size" /
"settings_qpack_blocked_streams" /
"settings_enable_connect_protocol" /
"settings_h3_datagram" /
"reserved" /
"unknown"
{: #h3settingsframe-def title="HTTP3SettingsFrame definition"}
HTTP3PushPromiseFrame = {
frame_type: "push_promise"
push_id: uint64
headers: [* HTTP3HTTPField]
}
{: #h3pushpromiseframe-def title="HTTP3PushPromiseFrame definition"}
HTTP3GoawayFrame = {
frame_type: "goaway"
; Either stream_id or push_id.
; This is implicit from the sender of the frame
id: uint64
}
{: #h3goawayframe-def title="HTTP3GoawayFrame definition"}
HTTP3MaxPushIDFrame = {
frame_type: "max_push_id"
push_id: uint64
}
{: #h3maxpushidframe-def title="HTTP3MaxPushIDFrame definition"}
The PRIORITY_UPDATE frame is defined in {{!RFC9218}}.
HTTP3PriorityUpdateFrame = {
frame_type: "priority_update"
; if the prioritized element is a request stream
? stream_id: uint64
; if the prioritized element is a push stream
? push_id: uint64
priority_field_value: HTTP3Priority
}
; The priority value in ASCII text, encoded using Structured Fields
; Example: u=5, i
HTTP3Priority = text
{: #h3priorityupdateframe-def title="HTTP3PriorityUpdateFrame definition"}
HTTP3ReservedFrame = {
frame_type: "reserved"
? length: uint64
}
{: #h3reservedframe-def title="HTTP3ReservedFrame definition"}
The frame_type_bytes field is the numerical value without variable-length integer encoding.
HTTP3UnknownFrame = {
frame_type: "unknown"
frame_type_bytes: uint64
? raw: RawInfo
}
{: #h3unknownframe-def title="HTTP3UnknownFrame definition"}
HTTP3ApplicationError = "http_no_error" /
"http_general_protocol_error" /
"http_internal_error" /
"http_stream_creation_error" /
"http_closed_critical_stream" /
"http_frame_unexpected" /
"http_frame_error" /
"http_excessive_load" /
"http_id_error" /
"http_settings_error" /
"http_missing_settings" /
"http_request_rejected" /
"http_request_cancelled" /
"http_request_incomplete" /
"http_early_response" /
"http_connect_error" /
"http_version_fallback"
{: #h3-applicationerror-def title="HTTP3ApplicationError definition"}
The HTTP3ApplicationError extends the general $ApplicationError definition in the qlog QUIC document, see {{QLOG-QUIC}}.
; ensure HTTP errors are properly validated in QUIC events as well
; e.g., QUIC's ConnectionClose Frame
$ApplicationError /= HTTP3ApplicationError
The security and privacy considerations discussed in {{QLOG-MAIN}} apply to this document as well.
This document registers a new entry in the "qlog event schema URIs" registry.
Event schema URI: : urn:ietf:params:qlog:events:http3
Namespace : http3
Event Types : parameters_set,parameters_restored,stream_type_set,priority_updated,frame_created,frame_parsed,datagram_created,datagram_parsed,push_resolved
Description: : Event definitions related to the HTTP/3 application protocol.
Reference: : This Document
--- back
{:numbered="false"}
Much of the initial work by Robin Marx was done at the Hasselt and KU Leuven Universities.
Thanks to Jana Iyengar, Brian Trammell, Dmitri Tikhonov, Stephen Petrides, Jari Arkko, Marcus Ihlar, Victor Vasiliev, Mirja Kühlewind, Jeremy Lainé, Kazu Yamamoto, Christian Huitema, Hugo Landau and Jonathan Lennox for their feedback and suggestions.
{:numbered="false" removeinrfc="true"}
{:numbered="false"}
- Removed individual categories and put every event in the single
http3
event schema namespace. Major change (#439) - Changed protocol id from
HTTP3
toHTTP/3
(#428)
{:numbered="false"}
- TODO (we forgot...)
{:numbered="false"}
- ProtocolEventBody is now called ProtocolEventData (#352)
- Editorial changes (#402)
{:numbered="false"}
- Removed all qpack event definitions (#335)
- Various editorial changes
{:numbered="false"}
- Renamed 'http' category to 'h3' (#300)
- H3HTTPField.value is now optional (#296)
- Added definitions for RFC9297 (HTTP/3 Datagram extension) (#310)
- Added definitions for RFC9218 (HTTP Extensible Prioritizations extension) (#312)
- Added definitions for RFC9220 (Extended Connect extension) (#325)
- Editorial and formatting changes (#298, #258, #299, #304, #327)
{:numbered="false"}
- Ensured consistent use of RawInfo to indicate raw wire bytes (#243)
- Changed HTTPStreamTypeSet:raw_stream_type to stream_type_value (#54)
- Changed HTTPUnknownFrame:raw_frame_type to frame_type_value (#54)
- Renamed max_header_list_size to max_field_section_size (#282)
{:numbered="false"}
- Renamed HTTPStreamType data to request (#222)
- Added HTTPStreamType value unknown (#227)
- Added HTTPUnknownFrame (#224)
- Replaced old and new fields with stream_type in HTTPStreamTypeSet (#240)
- Changed HTTPFrame to a CDDL plug type (#257)
- Moved data definitions out of the appendix into separate sections
- Added overview Table of Contents
{:numbered="false"}
- No changes - new draft to prevent expiration
{:numbered="false"}
- Change the data definition language from TypeScript to CDDL (#143)
{:numbered="false"}
- These changes were done in preparation of the adoption of the drafts by the QUIC working group (#137)
- Split QUIC and HTTP/3 events into two separate documents
- Moved RawInfo, Importance, Generic events and Simulation events to the main schema document.
{:numbered="false"}
Major changes:
- Moved data_moved from http to transport. Also made the "from" and "to" fields flexible strings instead of an enum (#111,#65)
- Moved packet_type fields to PacketHeader. Moved packet_size field out of PacketHeader to RawInfo:length (#40)
- Made events that need to log packet_type and packet_number use a header field instead of logging these fields individually
- Added support for logging retry, stateless reset and initial tokens (#94,#86,#117)
- Moved separate general event categories into a single category "generic" (#47)
- Added "transport:connection_closed" event (#43,#85,#78,#49)
- Added version_information and alpn_information events (#85,#75,#28)
- Added parameters_restored events to help clarify 0-RTT behaviour (#88)
Smaller changes:
- Merged loss_timer events into one loss_timer_updated event
- Field data types are now strongly defined (#10,#39,#36,#115)
- Renamed qpack instruction_received and instruction_sent to instruction_created and instruction_parsed (#114)
- Updated qpack:dynamic_table_updated.update_type. It now has the value "inserted" instead of "added" (#113)
- Updated qpack:dynamic_table_updated. It now has an "owner" field to differentiate encoder vs decoder state (#112)
- Removed push_allowed from http:parameters_set (#110)
- Removed explicit trigger field indications from events, since this was moved to be a generic property of the "data" field (#80)
- Updated transport:connection_id_updated to be more in line with other similar events. Also dropped importance from Core to Base (#45)
- Added length property to PaddingFrame (#34)
- Added packet_number field to transport:frames_processed (#74)
- Added a way to generically log packet header flags (first 8 bits) to PacketHeader
- Added additional guidance on which events to log in which situations (#53)
- Added "simulation:scenario" event to help indicate simulation details
- Added "packets_acked" event (#107)
- Added "datagram_ids" to the datagram_X and packet_X events to allow tracking of coalesced QUIC packets (#91)
- Extended connection_state_updated with more fine-grained states (#49)
{:numbered="false"}
- Event and category names are now all lowercase
- Added many new events and their definitions
- "type" fields have been made more specific (especially important for PacketType fields, which are now called packet_type instead of type)
- Events are given an importance indicator (issue #22)
- Event names are more consistent and use past tense (issue #21)
- Triggers have been redefined as properties of the "data" field and updated for most events (issue #23)