-
Notifications
You must be signed in to change notification settings - Fork 86
/
span_ext.rs
209 lines (198 loc) · 8.07 KB
/
span_ext.rs
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
201
202
203
204
205
206
207
208
209
use crate::layer::WithContext;
use opentelemetry::{trace::SpanContext, Context, Key, KeyValue, Value};
/// Utility functions to allow tracing [`Span`]s to accept and return
/// [OpenTelemetry] [`Context`]s.
///
/// [`Span`]: tracing::Span
/// [OpenTelemetry]: https://opentelemetry.io
/// [`Context`]: opentelemetry::Context
pub trait OpenTelemetrySpanExt {
/// Associates `self` with a given OpenTelemetry trace, using the provided
/// parent [`Context`].
///
/// [`Context`]: opentelemetry::Context
///
/// # Examples
///
/// ```rust
/// use opentelemetry::{propagation::TextMapPropagator, trace::TraceContextExt};
/// use opentelemetry_sdk::propagation::TraceContextPropagator;
/// use tracing_opentelemetry::OpenTelemetrySpanExt;
/// use std::collections::HashMap;
/// use tracing::Span;
///
/// // Example carrier, could be a framework header map that impls otel's `Extractor`.
/// let mut carrier = HashMap::new();
///
/// // Propagator can be swapped with b3 propagator, jaeger propagator, etc.
/// let propagator = TraceContextPropagator::new();
///
/// // Extract otel parent context via the chosen propagator
/// let parent_context = propagator.extract(&carrier);
///
/// // Generate a tracing span as usual
/// let app_root = tracing::span!(tracing::Level::INFO, "app_start");
///
/// // Assign parent trace from external context
/// app_root.set_parent(parent_context.clone());
///
/// // Or if the current span has been created elsewhere:
/// Span::current().set_parent(parent_context);
/// ```
fn set_parent(&self, cx: Context);
/// Associates `self` with a given OpenTelemetry trace, using the provided
/// followed span [`SpanContext`].
///
/// [`SpanContext`]: opentelemetry::trace::SpanContext
///
/// # Examples
///
/// ```rust
/// use opentelemetry::{propagation::TextMapPropagator, trace::TraceContextExt};
/// use opentelemetry_sdk::propagation::TraceContextPropagator;
/// use tracing_opentelemetry::OpenTelemetrySpanExt;
/// use std::collections::HashMap;
/// use tracing::Span;
///
/// // Example carrier, could be a framework header map that impls otel's `Extractor`.
/// let mut carrier = HashMap::new();
///
/// // Propagator can be swapped with b3 propagator, jaeger propagator, etc.
/// let propagator = TraceContextPropagator::new();
///
/// // Extract otel context of linked span via the chosen propagator
/// let linked_span_otel_context = propagator.extract(&carrier);
///
/// // Extract the linked span context from the otel context
/// let linked_span_context = linked_span_otel_context.span().span_context().clone();
///
/// // Generate a tracing span as usual
/// let app_root = tracing::span!(tracing::Level::INFO, "app_start");
///
/// // Assign linked trace from external context
/// app_root.add_link(linked_span_context);
///
/// // Or if the current span has been created elsewhere:
/// let linked_span_context = linked_span_otel_context.span().span_context().clone();
/// Span::current().add_link(linked_span_context);
/// ```
fn add_link(&self, cx: SpanContext);
/// Associates `self` with a given OpenTelemetry trace, using the provided
/// followed span [`SpanContext`] and attributes.
///
/// [`SpanContext`]: opentelemetry::trace::SpanContext
fn add_link_with_attributes(&self, cx: SpanContext, attributes: Vec<KeyValue>);
/// Extracts an OpenTelemetry [`Context`] from `self`.
///
/// [`Context`]: opentelemetry::Context
///
/// # Examples
///
/// ```rust
/// use opentelemetry::Context;
/// use tracing_opentelemetry::OpenTelemetrySpanExt;
/// use tracing::Span;
///
/// fn make_request(cx: Context) {
/// // perform external request after injecting context
/// // e.g. if the request's headers impl `opentelemetry::propagation::Injector`
/// // then `propagator.inject_context(cx, request.headers_mut())`
/// }
///
/// // Generate a tracing span as usual
/// let app_root = tracing::span!(tracing::Level::INFO, "app_start");
///
/// // To include tracing context in client requests from _this_ app,
/// // extract the current OpenTelemetry context.
/// make_request(app_root.context());
///
/// // Or if the current span has been created elsewhere:
/// make_request(Span::current().context())
/// ```
fn context(&self) -> Context;
/// Sets an OpenTelemetry attribute directly for this span, bypassing `tracing`.
/// If fields set here conflict with `tracing` fields, the `tracing` fields will supersede fields set with `set_attribute`.
/// This allows for more than 32 fields.
///
/// # Examples
///
/// ```rust
/// use opentelemetry::Context;
/// use tracing_opentelemetry::OpenTelemetrySpanExt;
/// use tracing::Span;
///
/// // Generate a tracing span as usual
/// let app_root = tracing::span!(tracing::Level::INFO, "app_start");
///
/// // Set the `http.request.header.x_forwarded_for` attribute to `example`.
/// app_root.set_attribute("http.request.header.x_forwarded_for", "example");
/// ```
fn set_attribute(&self, key: impl Into<Key>, value: impl Into<Value>);
}
impl OpenTelemetrySpanExt for tracing::Span {
fn set_parent(&self, cx: Context) {
let mut cx = Some(cx);
self.with_subscriber(move |(id, subscriber)| {
if let Some(get_context) = subscriber.downcast_ref::<WithContext>() {
get_context.with_context(subscriber, id, move |data, _tracer| {
if let Some(cx) = cx.take() {
data.parent_cx = cx;
}
});
}
});
}
fn add_link(&self, cx: SpanContext) {
self.add_link_with_attributes(cx, Vec::new())
}
fn add_link_with_attributes(&self, cx: SpanContext, attributes: Vec<KeyValue>) {
if cx.is_valid() {
let mut cx = Some(cx);
let mut att = Some(attributes);
self.with_subscriber(move |(id, subscriber)| {
if let Some(get_context) = subscriber.downcast_ref::<WithContext>() {
get_context.with_context(subscriber, id, move |data, _tracer| {
if let Some(cx) = cx.take() {
let attr = att.take().unwrap_or_default();
let follows_link = opentelemetry::trace::Link::new(cx, attr, 0);
data.builder
.links
.get_or_insert_with(|| Vec::with_capacity(1))
.push(follows_link);
}
});
}
});
}
}
fn context(&self) -> Context {
let mut cx = None;
self.with_subscriber(|(id, subscriber)| {
if let Some(get_context) = subscriber.downcast_ref::<WithContext>() {
get_context.with_context(subscriber, id, |builder, tracer| {
cx = Some(tracer.sampled_context(builder));
})
}
});
cx.unwrap_or_default()
}
fn set_attribute(&self, key: impl Into<Key>, value: impl Into<Value>) {
self.with_subscriber(move |(id, subscriber)| {
if let Some(get_context) = subscriber.downcast_ref::<WithContext>() {
let mut key = Some(key.into());
let mut value = Some(value.into());
get_context.with_context(subscriber, id, move |builder, _| {
if builder.builder.attributes.is_none() {
builder.builder.attributes = Some(Default::default());
}
builder
.builder
.attributes
.as_mut()
.unwrap()
.push(KeyValue::new(key.take().unwrap(), value.take().unwrap()));
})
}
});
}
}