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// Cadence - An extensible Statsd client for Rust! // // Copyright 2015-2019 TSH Labs // // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your // option. This file may not be copied, modified, or distributed // except according to those terms. use std::fmt; use std::net::{ToSocketAddrs, UdpSocket}; use std::panic::RefUnwindSafe; use std::sync::Arc; use std::time::Duration; use crate::builder::{MetricBuilder, MetricFormatter}; use crate::sinks::{MetricSink, UdpMetricSink}; use crate::types::{ Counter, ErrorKind, Gauge, Histogram, Meter, Metric, MetricError, MetricResult, Set, Timer, }; /// Trait for incrementing and decrementing counters. /// /// Counters are simple values incremented or decremented by a client. The /// rates at which these events occur or average values will be determined /// by the server receiving them. Examples of counter uses include number /// of logins to a system or requests received. /// /// See the [Statsd spec](https://github.com/b/statsd_spec) for more /// information. /// /// Note that tags are a [Datadog](https://docs.datadoghq.com/developers/dogstatsd/) /// extension to Statsd and may not be supported by your server. pub trait Counted { /// Increment the counter by `1` fn incr(&self, key: &str) -> MetricResult<Counter> { self.count(key, 1) } /// Increment the counter by `1` and return a `MetricBuilder` that can /// be used to add tags to the metric. fn incr_with_tags<'a>(&'a self, key: &'a str) -> MetricBuilder<'_, '_, Counter> { self.count_with_tags(key, 1) } /// Decrement the counter by `1` fn decr(&self, key: &str) -> MetricResult<Counter> { self.count(key, -1) } /// Decrement the counter by `1` and return a `MetricBuilder that can /// be used to add tags to the metric. fn decr_with_tags<'a>(&'a self, key: &'a str) -> MetricBuilder<'_, '_, Counter> { self.count_with_tags(key, -1) } /// Increment or decrement the counter by the given amount fn count(&self, key: &str, count: i64) -> MetricResult<Counter> { self.count_with_tags(key, count).try_send() } /// Increment or decrement the counter by the given amount and return /// a `MetricBuilder` that can be used to add tags to the metric. fn count_with_tags<'a>(&'a self, key: &'a str, count: i64) -> MetricBuilder<'_, '_, Counter>; } /// Trait for recording timings in milliseconds. /// /// Timings are a positive number of milliseconds between a start and end /// time. Examples include time taken to render a web page or time taken /// for a database call to return. /// /// See the [Statsd spec](https://github.com/b/statsd_spec) for more /// information. /// /// Note that tags are a [Datadog](https://docs.datadoghq.com/developers/dogstatsd/) /// extension to Statsd and may not be supported by your server. pub trait Timed { /// Record a timing in milliseconds with the given key fn time(&self, key: &str, time: u64) -> MetricResult<Timer> { self.time_with_tags(key, time).try_send() } /// Record a timing in milliseconds with the given key and return a /// `MetricBuilder` that can be used to add tags to the metric. fn time_with_tags<'a>(&'a self, key: &'a str, time: u64) -> MetricBuilder<'_, '_, Timer>; /// Record a timing in milliseconds with the given key /// /// The duration will be truncated to millisecond precision. If the /// duration cannot be represented as a `u64` an error will be returned. fn time_duration(&self, key: &str, duration: Duration) -> MetricResult<Timer> { self.time_duration_with_tags(key, duration).try_send() } /// Record a timing in milliseconds with the given key and return a /// `MetricBuilder` that can be used to add tags to the metric. /// /// The duration will be truncated to millisecond precision. If the /// duration cannot be represented as a `u64` an error will be deferred /// and returned when `MetricBuilder::send()` is called. fn time_duration_with_tags<'a>( &'a self, key: &'a str, duration: Duration, ) -> MetricBuilder<'_, '_, Timer>; } /// Trait for recording gauge values. /// /// Gauge values are an instantaneous measurement of a value determined /// by the client. They do not change unless changed by the client. Examples /// include things like load average or how many connections are active. /// /// See the [Statsd spec](https://github.com/b/statsd_spec) for more /// information. /// /// Note that tags are a [Datadog](https://docs.datadoghq.com/developers/dogstatsd/) /// extension to Statsd and may not be supported by your server. pub trait Gauged { /// Record a gauge value with the given key fn gauge(&self, key: &str, value: u64) -> MetricResult<Gauge> { self.gauge_with_tags(key, value).try_send() } /// Record a gauge value with the given key and return a `MetricBuilder` /// that can be used to add tags to the metric. fn gauge_with_tags<'a>(&'a self, key: &'a str, value: u64) -> MetricBuilder<'_, '_, Gauge>; } /// Trait for recording meter values. /// /// Meter values measure the rate at which events occur. These rates are /// determined by the server, the client simply indicates when they happen. /// Meters can be thought of as increment-only counters. Examples include /// things like number of requests handled or number of times something is /// flushed to disk. /// /// See the [Statsd spec](https://github.com/b/statsd_spec) for more /// information. /// /// Note that tags are a [Datadog](https://docs.datadoghq.com/developers/dogstatsd/) /// extension to Statsd and may not be supported by your server. pub trait Metered { /// Record a single metered event with the given key fn mark(&self, key: &str) -> MetricResult<Meter> { self.meter(key, 1) } /// Record a single metered event with the given key and return a /// `MetricBuilder` that can be used to add tags to the metric. fn mark_with_tags<'a>(&'a self, key: &'a str) -> MetricBuilder<'_, '_, Meter> { self.meter_with_tags(key, 1) } /// Record a meter value with the given key fn meter(&self, key: &str, value: u64) -> MetricResult<Meter> { self.meter_with_tags(key, value).try_send() } /// Record a meter value with the given key and return a `MetricBuilder` /// that can be used to add tags to the metric. fn meter_with_tags<'a>(&'a self, key: &'a str, value: u64) -> MetricBuilder<'_, '_, Meter>; } /// Trait for recording histogram values. /// /// Histogram values are positive values that can represent anything, whose /// statistical distribution is calculated by the server. The values can be /// timings, amount of some resource consumed, size of HTTP responses in /// some application, etc. Histograms can be thought of as a more general /// form of timers. /// /// See the [Statsd spec](https://github.com/b/statsd_spec) for more /// information. /// /// Note that tags and histograms are a /// [Datadog](https://docs.datadoghq.com/developers/dogstatsd/) extension to /// Statsd and may not be supported by your server. pub trait Histogrammed { /// Record a single histogram value with the given key fn histogram(&self, key: &str, value: u64) -> MetricResult<Histogram> { self.histogram_with_tags(key, value).try_send() } /// Record a single histogram value with the given key and return a /// `MetricBuilder` that can be used to add tags to the metric. fn histogram_with_tags<'a>(&'a self, key: &'a str, value: u64) -> MetricBuilder<'_, '_, Histogram>; } /// Trait for recording set values. /// /// Sets count the number of unique elements in a group. You can use them to, /// for example, count the unique visitors to your site. /// /// See the [Statsd spec](https://github.com/b/statsd_spec) for more /// information. pub trait Setted { /// Record a single set value with the given key fn set(&self, key: &str, value: i64) -> MetricResult<Set> { self.set_with_tags(key, value).try_send() } /// Record a single set value with the given key and return a /// `MetricBuilder` that can be used to add tags to the metric. fn set_with_tags<'a>(&'a self, key: &'a str, value: i64) -> MetricBuilder<'_, '_, Set>; } /// Trait that encompasses all other traits for sending metrics. /// /// If you wish to use `StatsdClient` with a generic type or place a /// `StatsdClient` instance behind a pointer (such as a `Box`) this will allow /// you to reference all the implemented methods for recording metrics, while /// using a single trait. An example of this is shown below. /// /// ``` /// use cadence::{MetricClient, StatsdClient, NopMetricSink}; /// /// let client: Box<MetricClient> = Box::new(StatsdClient::from_sink( /// "prefix", NopMetricSink)); /// /// client.count("some.counter", 1).unwrap(); /// client.time("some.timer", 42).unwrap(); /// client.gauge("some.gauge", 8).unwrap(); /// client.meter("some.meter", 13).unwrap(); /// client.histogram("some.histogram", 4).unwrap(); /// client.set("some.set", 5).unwrap(); /// ``` pub trait MetricClient: Counted + Timed + Gauged + Metered + Histogrammed + Setted {} /// Typically internal methods for sending metrics and handling errors. /// /// This trait exposes methods of the client that would normally be internal /// but may be useful for consumers of the library to extend it in unforseen /// ways. /// /// This trait is not exposed in the `prelude` module since it isn't required /// to use the client for sending metrics. It is only exposed in the `ext` /// module which is used to encompass extension points for the library. /// /// # Example /// /// ``` /// use cadence::{Metric, MetricResult, StatsdClient, NopMetricSink}; /// use cadence::ext::MetricBackend; /// /// struct CustomMetric { /// repr: String, /// } /// /// impl Metric for CustomMetric { /// fn as_metric_str(&self) -> &str { /// &self.repr /// } /// } /// /// impl From<String> for CustomMetric { /// fn from(v: String) -> Self { /// CustomMetric { repr: v } /// } /// } /// /// struct MyCustomClient { /// prefix: String, /// wrapped: StatsdClient, /// } /// /// impl MyCustomClient { /// fn new(prefix: &str, client: StatsdClient) -> Self { /// MyCustomClient { /// prefix: prefix.to_string(), /// wrapped: client, /// } /// } /// /// fn send_event(&self, key: &str, val: i64) -> MetricResult<CustomMetric> { /// let metric = CustomMetric::from(format!("{}.{}:{}|e", self.prefix, key, val)); /// self.wrapped.send_metric(&metric)?; /// Ok(metric) /// } /// /// fn send_event_quietly(&self, key: &str, val: i64) { /// if let Err(e) = self.send_event(key, val) { /// self.wrapped.consume_error(e); /// } /// } /// } /// /// let prefix = "some.prefix"; /// let inner = StatsdClient::from_sink(&prefix, NopMetricSink); /// let custom = MyCustomClient::new(&prefix, inner); /// /// custom.send_event("some.event", 123).unwrap(); /// custom.send_event_quietly("some.event", 456); /// ``` pub trait MetricBackend { /// Send a full formed `Metric` implementation via the underlying `MetricSink` /// /// Obtain a `&str` representation of a metric, encode it as UTF-8 bytes, and /// send it to the underlying `MetricSink`, verbatim. Note that the metric is /// expected to be full formed already, including any prefix or tags. /// /// Note that if you simply want to emit standard metrics, you don't need to /// use this method. This is only useful if you are extending Cadence with a /// custom metric type or something similar. fn send_metric<M>(&self, metric: &M) -> MetricResult<()> where M: Metric; /// Consume a possible error from attempting to send a metric. /// /// When callers have elected to quietly send metrics via the `MetricBuilder::send()` /// method, this method will be invoked if an error is encountered. By default the /// handler is a no-op, meaning that errors are discarded. /// /// Note that if you simply want to emit standard metrics, you don't need to /// use this method. This is only useful if you are extending Cadence with a /// custom metric type or something similar. fn consume_error(&self, err: MetricError); } /// Builder for creating and customizing `StatsdClient` instances. /// /// Instances of the builder should be created by calling the `::builder()` /// method on the `StatsClient` struct. /// /// # Example /// /// ``` /// use cadence::prelude::*; /// use cadence::{MetricError, StatsdClient, NopMetricSink}; /// /// fn my_error_handler(err: MetricError) { /// println!("Metric error! {}", err); /// } /// /// let client = StatsdClient::builder("prefix", NopMetricSink) /// .with_error_handler(my_error_handler) /// .build(); /// /// client.count("something", 123); /// client.count_with_tags("some.counter", 42) /// .with_tag("region", "us-east-2") /// .send(); /// ``` pub struct StatsdClientBuilder { prefix: String, sink: Box<dyn MetricSink + Sync + Send + RefUnwindSafe>, errors: Box<dyn Fn(MetricError) -> () + Sync + Send + RefUnwindSafe>, } impl StatsdClientBuilder { // Set the required fields and defaults for optional fields fn new<T>(prefix: &str, sink: T) -> Self where T: MetricSink + Sync + Send + RefUnwindSafe + 'static, { StatsdClientBuilder { // required prefix: Self::get_formatted_prefix(prefix), sink: Box::new(sink), // optional with defaults errors: Box::new(nop_error_handler), } } /// Set an error handler to use for metrics sent via `MetricBuilder::send()` /// /// The error handler is only invoked when metrics are not able to be sent /// correctly. Either due to invalid input, I/O errors encountered when trying /// to send them via a `MetricSink`, or some other reason. /// /// The error handler should consume the error without panicking. The error /// may be logged, printed to stderr, discarded, etc. - this is up to the /// implementation. pub fn with_error_handler<F>(mut self, errors: F) -> Self where F: Fn(MetricError) -> () + Sync + Send + RefUnwindSafe + 'static, { self.errors = Box::new(errors); self } /// Construct a new `StatsdClient` instance based on current settings. pub fn build(self) -> StatsdClient { StatsdClient::from_builder(self) } fn get_formatted_prefix(prefix: &str) -> String { if prefix.is_empty() { String::new() } else { format!("{}.", prefix.trim_end_matches('.')) } } } /// Client for Statsd that implements various traits to record metrics. /// /// # Traits /// /// The client is the main entry point for users of this library. It supports /// several traits for recording metrics of different types. /// /// * `Counted` for emitting counters. /// * `Timed` for emitting timings. /// * `Gauged` for emitting gauge values. /// * `Metered` for emitting meter values. /// * `Histogrammed` for emitting histogram values. /// * `Setted` for emitting set values. /// * `MetricClient` for a combination of all of the above. /// /// For more information about the uses for each type of metric, see the /// documentation for each mentioned trait. /// /// # Sinks /// /// The client uses some implementation of a `MetricSink` to emit the metrics. /// /// In simple use cases when performance isn't critical, the `UdpMetricSink` /// is an acceptable choice since it is the simplest to use and understand. /// /// When performance is more important, users will want to use the /// `BufferedUdpMetricSink` in combination with the `QueuingMetricSink` for /// maximum isolation between the sending of metrics and your application as well /// as minimum overhead when sending metrics. /// /// # Threading /// /// The `StatsdClient` is designed to work in a multithreaded application. All /// parts of the client can be shared between threads (i.e. it is `Send` and /// `Sync`). Some common ways to use the client in a multithreaded environment /// are given below. /// /// In each of these examples, we create a struct `MyRequestHandler` that has a /// single method that spawns a thread to do some work and emit a metric. /// /// ## Wrapping With An `Arc` /// /// One option is to put all accesses to the client behind an atomic reference /// counting pointer (`std::sync::Arc`). If you are doing this, it makes sense /// to just refer to the client by the trait of all its methods for recording /// metrics (`MetricClient`) as well as the `Send` and `Sync` traits since the /// idea is to share this between threads. /// /// ``` no_run /// use std::panic::RefUnwindSafe; /// use std::net::UdpSocket; /// use std::sync::Arc; /// use std::thread; /// use cadence::prelude::*; /// use cadence::{StatsdClient, BufferedUdpMetricSink, DEFAULT_PORT}; /// /// struct MyRequestHandler { /// metrics: Arc<MetricClient + Send + Sync + RefUnwindSafe>, /// } /// /// impl MyRequestHandler { /// fn new() -> MyRequestHandler { /// let socket = UdpSocket::bind("0.0.0.0:0").unwrap(); /// let host = ("localhost", DEFAULT_PORT); /// let sink = BufferedUdpMetricSink::from(host, socket).unwrap(); /// MyRequestHandler { /// metrics: Arc::new(StatsdClient::from_sink("some.prefix", sink)) /// } /// } /// /// fn handle_some_request(&self) -> Result<(), String> { /// let metric_ref = self.metrics.clone(); /// let _t = thread::spawn(move || { /// println!("Hello from the thread!"); /// metric_ref.incr("request.handler"); /// }); /// /// Ok(()) /// } /// } /// ``` /// /// ## Clone Per Thread /// /// Another option for sharing the client between threads is just to clone /// client itself. Clones of the client are relatively cheap, typically only /// requiring a single heap allocation (of a `String`). While this cost isn't /// nothing, it's not too bad. An example of this is given below. /// /// ``` no_run /// use std::net::UdpSocket; /// use std::thread; /// use cadence::prelude::*; /// use cadence::{StatsdClient, BufferedUdpMetricSink, DEFAULT_PORT}; /// /// struct MyRequestHandler { /// metrics: StatsdClient, /// } /// /// impl MyRequestHandler { /// fn new() -> MyRequestHandler { /// let socket = UdpSocket::bind("0.0.0.0:0").unwrap(); /// let host = ("localhost", DEFAULT_PORT); /// let sink = BufferedUdpMetricSink::from(host, socket).unwrap(); /// MyRequestHandler { /// metrics: StatsdClient::from_sink("some.prefix", sink) /// } /// } /// /// fn handle_some_request(&self) -> Result<(), String> { /// let metric_clone = self.metrics.clone(); /// let _t = thread::spawn(move || { /// println!("Hello from the thread!"); /// metric_clone.incr("request.handler"); /// }); /// /// Ok(()) /// } /// } /// ``` /// /// As you can see, cloning the client itself looks a lot like using it with /// an `Arc`. #[derive(Clone)] pub struct StatsdClient { prefix: String, sink: Arc<dyn MetricSink + Sync + Send + RefUnwindSafe>, errors: Arc<dyn Fn(MetricError) -> () + Sync + Send + RefUnwindSafe>, } impl StatsdClient { /// Create a new client instance that will use the given prefix for /// all metrics emitted to the given `MetricSink` implementation. /// /// Note that this client will discard errors encountered when /// sending metrics via the `MetricBuilder::send()` method. /// /// # No-op Example /// /// ``` /// use cadence::{StatsdClient, NopMetricSink}; /// /// let prefix = "my.stats"; /// let client = StatsdClient::from_sink(prefix, NopMetricSink); /// ``` /// /// # UDP Socket Example /// /// ``` /// use std::net::UdpSocket; /// use cadence::{StatsdClient, UdpMetricSink, DEFAULT_PORT}; /// /// let prefix = "my.stats"; /// let host = ("127.0.0.1", DEFAULT_PORT); /// /// let socket = UdpSocket::bind("0.0.0.0:0").unwrap(); /// socket.set_nonblocking(true).unwrap(); /// /// let sink = UdpMetricSink::from(host, socket).unwrap(); /// let client = StatsdClient::from_sink(prefix, sink); /// ``` /// /// # Buffered UDP Socket Example /// /// ``` /// use std::net::UdpSocket; /// use cadence::{StatsdClient, BufferedUdpMetricSink, DEFAULT_PORT}; /// /// let prefix = "my.stats"; /// let host = ("127.0.0.1", DEFAULT_PORT); /// /// let socket = UdpSocket::bind("0.0.0.0:0").unwrap(); /// /// let sink = BufferedUdpMetricSink::from(host, socket).unwrap(); /// let client = StatsdClient::from_sink(prefix, sink); /// ``` pub fn from_sink<T>(prefix: &str, sink: T) -> Self where T: MetricSink + Sync + Send + RefUnwindSafe + 'static, { Self::builder(prefix, sink).build() } /// Create a new client instance that will use the given prefix to send /// metrics to the given host over UDP using an appropriate sink. /// /// The created UDP socket will be put into non-blocking mode. /// /// Note that this client will discard errors encountered when /// sending metrics via the `MetricBuilder::send()` method. /// /// # Example /// /// ```no_run /// use cadence::{StatsdClient, UdpMetricSink}; /// /// let prefix = "my.stats"; /// let host = ("metrics.example.com", 8125); /// /// let client = StatsdClient::from_udp_host(prefix, host); /// ``` /// /// # Failures /// /// This method may fail if: /// /// * It is unable to create a local UDP socket. /// * It is unable to put the UDP socket into non-blocking mode. /// * It is unable to resolve the hostname of the metric server. /// * The host address is otherwise unable to be parsed. pub fn from_udp_host<A>(prefix: &str, host: A) -> MetricResult<Self> where A: ToSocketAddrs, { let socket = UdpSocket::bind("0.0.0.0:0")?; socket.set_nonblocking(true)?; let sink = UdpMetricSink::from(host, socket)?; Ok(StatsdClient::builder(prefix, sink).build()) } /// Create a new builder with the provided prefix and metric sink. /// /// A prefix and a metric sink are required to create a new client /// instance. All other optional customizations can be set by calling /// methods on the returned builder. Any customizations that aren't /// set by the caller will use defaults. /// /// Note, though a metric prefix is required, you may pass an empty /// string as a prefix. In this case, the metrics emitted will use only /// the bare keys supplied when you call the various methods to emit /// metrics. /// /// General defaults: /// /// * A no-op error handler will be used by default. Note that this /// only affects errors encountered when using the `MetricBuilder::send()` /// method (as opposed to `.try_send()` or any other method for sending /// metrics). /// /// # Example /// /// ``` /// use cadence::prelude::*; /// use cadence::{StatsdClient, MetricError, NopMetricSink}; /// /// fn my_handler(err: MetricError) { /// println!("Metric error: {}", err); /// } /// /// let client = StatsdClient::builder("some.prefix", NopMetricSink) /// .with_error_handler(my_handler) /// .build(); /// /// client.gauge_with_tags("some.key", 7) /// .with_tag("region", "us-west-1") /// .send(); /// ``` pub fn builder<T>(prefix: &str, sink: T) -> StatsdClientBuilder where T: MetricSink + Sync + Send + RefUnwindSafe + 'static, { StatsdClientBuilder::new(prefix, sink) } // Create a new StatsdClient by consuming the builder fn from_builder(builder: StatsdClientBuilder) -> Self { StatsdClient { prefix: builder.prefix, sink: Arc::from(builder.sink), errors: Arc::from(builder.errors), } } } impl MetricBackend for StatsdClient { fn send_metric<M>(&self, metric: &M) -> MetricResult<()> where M: Metric, { let metric_string = metric.as_metric_str(); self.sink.emit(metric_string)?; Ok(()) } fn consume_error(&self, err: MetricError) { (self.errors)(err); } } impl fmt::Debug for StatsdClient { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { write!( f, "StatsdClient {{ prefix: {:?}, sink: ..., errors: ... }}", self.prefix ) } } impl Counted for StatsdClient { fn count_with_tags<'a>(&'a self, key: &'a str, count: i64) -> MetricBuilder<'_, '_, Counter> { let fmt = MetricFormatter::counter(&self.prefix, key, count); MetricBuilder::new(fmt, self) } } impl Timed for StatsdClient { fn time_with_tags<'a>(&'a self, key: &'a str, time: u64) -> MetricBuilder<'_, '_, Timer> { let fmt = MetricFormatter::timer(&self.prefix, key, time); MetricBuilder::new(fmt, self) } fn time_duration_with_tags<'a>( &'a self, key: &'a str, duration: Duration, ) -> MetricBuilder<'_, '_, Timer> { let secs_as_ms = duration.as_secs().checked_mul(1_000); let nanos_as_ms = u64::from(duration.subsec_nanos()).checked_div(1_000_000); let result = secs_as_ms .and_then(|v1| nanos_as_ms.and_then(|v2| v1.checked_add(v2))) .ok_or_else(|| MetricError::from((ErrorKind::InvalidInput, "u64 overflow"))); match result { Ok(millis) => self.time_with_tags(key, millis), Err(e) => MetricBuilder::from_error(e, self), } } } impl Gauged for StatsdClient { fn gauge_with_tags<'a>(&'a self, key: &'a str, value: u64) -> MetricBuilder<'_, '_, Gauge> { let fmt = MetricFormatter::gauge(&self.prefix, key, value); MetricBuilder::new(fmt, self) } } impl Metered for StatsdClient { fn meter_with_tags<'a>(&'a self, key: &'a str, value: u64) -> MetricBuilder<'_, '_, Meter> { let fmt = MetricFormatter::meter(&self.prefix, key, value); MetricBuilder::new(fmt, self) } } impl Histogrammed for StatsdClient { fn histogram_with_tags<'a>(&'a self, key: &'a str, value: u64) -> MetricBuilder<'_, '_, Histogram> { let fmt = MetricFormatter::histogram(&self.prefix, key, value); MetricBuilder::new(fmt, self) } } impl Setted for StatsdClient { fn set_with_tags<'a>(&'a self, key: &'a str, value: i64) -> MetricBuilder<'_, '_, Set> { let fmt = MetricFormatter::set(&self.prefix, key, value); MetricBuilder::new(fmt, self) } } impl MetricClient for StatsdClient {} #[allow(clippy::needless_pass_by_value)] fn nop_error_handler(_err: MetricError) { // nothing } #[cfg(test)] mod tests { use std::cell::RefCell; use std::io; use std::panic::RefUnwindSafe; use std::sync::atomic::{AtomicUsize, Ordering}; use std::sync::{Arc, Mutex}; use std::time::Duration; use std::u64; use super::{ Counted, Gauged, Histogrammed, Metered, MetricClient, Setted, StatsdClient, Timed, }; use crate::sinks::{MetricSink, NopMetricSink, QueuingMetricSink}; use crate::types::{ErrorKind, Metric, MetricError}; #[test] fn test_statsd_client_empty_prefix() { let client = StatsdClient::from_sink("", NopMetricSink); let res = client.count("some.method", 1); assert_eq!("some.method:1|c", res.unwrap().as_metric_str()); } #[test] fn test_statsd_client_count_with_tags() { let client = StatsdClient::from_sink("prefix", NopMetricSink); let res = client .count_with_tags("some.counter", 3) .with_tag("foo", "bar") .try_send(); assert_eq!( "prefix.some.counter:3|c|#foo:bar", res.unwrap().as_metric_str() ); } #[test] fn test_statsd_client_gauge_with_tags() { let client = StatsdClient::from_sink("prefix", NopMetricSink); let res = client .gauge_with_tags("some.gauge", 4) .with_tag("bucket", "A") .with_tag_value("file-server") .try_send(); assert_eq!( "prefix.some.gauge:4|g|#bucket:A,file-server", res.unwrap().as_metric_str() ); } #[test] fn test_statsd_client_meter_with_tags() { let client = StatsdClient::from_sink("prefix", NopMetricSink); let res = client .meter_with_tags("some.meter", 64) .with_tag("segment", "142") .with_tag_value("beta") .try_send(); assert_eq!( "prefix.some.meter:64|m|#segment:142,beta", res.unwrap().as_metric_str() ); } #[test] fn test_statsd_client_histogram_with_tags() { let client = StatsdClient::from_sink("prefix", NopMetricSink); let res = client .histogram_with_tags("some.histo", 27) .with_tag("host", "www03.example.com") .with_tag_value("rc1") .try_send(); assert_eq!( "prefix.some.histo:27|h|#host:www03.example.com,rc1", res.unwrap().as_metric_str() ); } #[test] fn test_statsd_client_time_duration() { let client = StatsdClient::from_sink("prefix", NopMetricSink); let res = client.time_duration("key", Duration::from_millis(157)); assert_eq!("prefix.key:157|ms", res.unwrap().as_metric_str()); } #[test] fn test_statsd_client_time_duration_with_overflow() { let client = StatsdClient::from_sink("prefix", NopMetricSink); let res = client.time_duration("key", Duration::from_secs(u64::MAX)); assert_eq!(ErrorKind::InvalidInput, res.unwrap_err().kind()) } #[test] fn test_statsd_client_time_duration_with_tags() { let client = StatsdClient::from_sink("prefix", NopMetricSink); let res = client .time_duration_with_tags("key", Duration::from_millis(157)) .with_tag("foo", "bar") .with_tag_value("quux") .try_send(); assert_eq!( "prefix.key:157|ms|#foo:bar,quux", res.unwrap().as_metric_str() ); } #[test] fn test_statsd_client_time_duration_with_tags_with_overflow() { let client = StatsdClient::from_sink("prefix", NopMetricSink); let res = client .time_duration_with_tags("key", Duration::from_secs(u64::MAX)) .with_tag("foo", "bar") .with_tag_value("quux") .try_send(); assert!(res.is_err()); assert_eq!(ErrorKind::InvalidInput, res.unwrap_err().kind()); } #[test] fn test_statsd_client_with_tags_send_success() { struct StoringSink { metrics: Arc<Mutex<RefCell<Vec<String>>>>, } impl MetricSink for StoringSink { fn emit(&self, metric: &str) -> io::Result<usize> { let mutex = self.metrics.as_ref(); let cell = mutex.lock().unwrap(); cell.borrow_mut().push(metric.to_owned()); Ok(0) } } fn panic_handler(err: MetricError) { panic!("Metric send error: {}", err); } let metrics = Arc::new(Mutex::new(RefCell::new(Vec::new()))); let metrics_ref = Arc::clone(&metrics); let sink = StoringSink { metrics: metrics_ref, }; let client = StatsdClient::builder("prefix", sink) .with_error_handler(panic_handler) .build(); client .incr_with_tags("some.key") .with_tag("test", "a") .send(); let mutex = metrics.as_ref(); let cell = mutex.lock().unwrap(); assert_eq!(1, cell.borrow().len()); } #[test] fn test_statsd_client_with_tags_send_error() { struct ErrorSink; impl MetricSink for ErrorSink { fn emit(&self, _metric: &str) -> io::Result<usize> { Err(io::Error::from(io::ErrorKind::Other)) } } let count = Arc::new(AtomicUsize::new(0)); let count_ref = Arc::clone(&count); let handler = move |_err: MetricError| { count_ref.fetch_add(1, Ordering::Release); }; let client = StatsdClient::builder("prefix", ErrorSink) .with_error_handler(handler) .build(); client .incr_with_tags("some.key") .with_tag("tier", "web") .send(); assert_eq!(1, count.load(Ordering::Acquire)); } #[test] fn test_statsd_client_set_no_tags() { let client = StatsdClient::from_sink("myapp", NopMetricSink); let res = client.set("some.set", 3); assert_eq!("myapp.some.set:3|s", res.unwrap().as_metric_str()); } #[test] fn test_statsd_client_set_with_tags() { let client = StatsdClient::from_sink("myapp", NopMetricSink); let res = client .set_with_tags("some.set", 3) .with_tag("foo", "bar") .try_send(); assert_eq!("myapp.some.set:3|s|#foo:bar", res.unwrap().as_metric_str()); } // The following tests really just ensure that we've actually // implemented all the traits we're supposed to correctly. If // we hadn't, this wouldn't compile. #[test] fn test_statsd_client_as_counted() { let client: Box<dyn Counted> = Box::new(StatsdClient::from_sink("prefix", NopMetricSink)); client.count("some.counter", 5).unwrap(); } #[test] fn test_statsd_client_as_timed() { let client: Box<dyn Timed> = Box::new(StatsdClient::from_sink("prefix", NopMetricSink)); client.time("some.timer", 20).unwrap(); } #[test] fn test_statsd_client_as_gauged() { let client: Box<dyn Gauged> = Box::new(StatsdClient::from_sink("prefix", NopMetricSink)); client.gauge("some.gauge", 32).unwrap(); } #[test] fn test_statsd_client_as_metered() { let client: Box<dyn Metered> = Box::new(StatsdClient::from_sink("prefix", NopMetricSink)); client.meter("some.meter", 9).unwrap(); } #[test] fn test_statsd_client_as_histogrammed() { let client: Box<dyn Histogrammed> = Box::new(StatsdClient::from_sink("prefix", NopMetricSink)); client.histogram("some.histogram", 4).unwrap(); } #[test] fn test_statsd_client_as_setted() { let client: Box<dyn Setted> = Box::new(StatsdClient::from_sink("myapp", NopMetricSink)); client.set("some.set", 5).unwrap(); } #[test] fn test_statsd_client_as_metric_client() { let client: Box<dyn MetricClient> = Box::new(StatsdClient::from_sink("prefix", NopMetricSink)); client.count("some.counter", 3).unwrap(); client.time("some.timer", 198).unwrap(); client.gauge("some.gauge", 4).unwrap(); client.meter("some.meter", 29).unwrap(); client.histogram("some.histogram", 32).unwrap(); client.set("some.set", 5).unwrap(); } #[test] fn test_statsd_client_as_thread_and_panic_safe() { let client: Box<dyn MetricClient + Send + Sync + RefUnwindSafe> = Box::new( StatsdClient::from_sink("prefix", QueuingMetricSink::from(NopMetricSink)), ); client.count("some.counter", 3).unwrap(); client.time("some.timer", 198).unwrap(); client.gauge("some.gauge", 4).unwrap(); client.meter("some.meter", 29).unwrap(); client.histogram("some.histogram", 32).unwrap(); client.set("some.set", 5).unwrap(); } }