feat: add option to output structured json

Author: GuillaumeLagrange

src/local_logger.rs

@@ -12,7 +12,7 @@ use log::Log;
 use simplelog::{CombinedLogger, SharedLogger};
 use std::io::Write;
 
-use crate::logger::{get_group_event, GroupEvent};
+use crate::logger::{get_group_event, get_json_event, GroupEvent, JsonEvent};
 
 pub const CODSPEED_U8_COLOR_CODE: u8 = 208; // #FF8700
 
@@ -66,7 +66,7 @@ impl Log for LocalLogger {
         if let Some(group_event) = get_group_event(record) {
             match group_event {
                 GroupEvent::Start(name) | GroupEvent::StartOpened(name) => {
-                    println!(
+                    eprintln!(
                         "\n{}",
                         style(format!("►►► {} ", name))
                             .bold()
@@ -89,7 +89,7 @@ impl Log for LocalLogger {
                         spinner.enable_steady_tick(Duration::from_millis(100));
                         SPINNER.lock().unwrap().replace(spinner);
                     } else {
-                        println!("{}...", name);
+                        eprintln!("{}...", name);
                     }
                 }
                 GroupEvent::End => {
@@ -105,6 +105,11 @@ impl Log for LocalLogger {
             return;
         }
 
+        if let Some(JsonEvent(json_string)) = get_json_event(record) {
+            println!("{json_string}");
+            return;
+        }
+
         suspend_progress_bar(|| print_record(record));
     }
 
@@ -124,12 +129,12 @@ fn print_record(record: &log::Record) {
     match record.level() {
         log::Level::Error => eprintln!("{}", error_style.apply_to(record.args())),
         log::Level::Warn => eprintln!("{}", warn_style.apply_to(record.args())),
-        log::Level::Info => println!("{}", info_style.apply_to(record.args())),
-        log::Level::Debug => println!(
+        log::Level::Info => eprintln!("{}", info_style.apply_to(record.args())),
+        log::Level::Debug => eprintln!(
             "{}",
             debug_style.apply_to(format!("[DEBUG::{}] {}", record.target(), record.args())),
         ),
-        log::Level::Trace => println!(
+        log::Level::Trace => eprintln!(
             "{}",
             trace_style.apply_to(format!("[TRACE::{}] {}", record.target(), record.args()))
         ),

src/logger.rs

@@ -71,3 +71,29 @@ pub(super) fn get_group_event(record: &log::Record) -> Option<GroupEvent> {
         _ => None,
     }
 }
+
+#[macro_export]
+/// Log a structured JSON output
+macro_rules! log_json {
+    ($value:expr) => {
+        log::log!(target: $crate::logger::JSON_TARGET, log::Level::Info, "{}", $value);
+    };
+}
+
+pub struct JsonEvent(pub String);
+
+pub const JSON_TARGET: &str = "codspeed::json";
+
+pub(super) fn get_json_event(record: &log::Record) -> Option<JsonEvent> {
+    match record.target() {
+        JSON_TARGET => {
+            let args = record.args().to_string();
+            if args.is_empty() {
+                None
+            } else {
+                Some(JsonEvent(args))
+            }
+        }
+        _ => None,
+    }
+}

src/prelude.rs

@@ -1,4 +1,4 @@
-pub use crate::{end_group, start_group, start_opened_group};
+pub use crate::{end_group, log_json, start_group, start_opened_group};
 #[allow(unused_imports)]
 pub use anyhow::{anyhow, bail, ensure, Context, Error, Result};
 pub use itertools::Itertools;

src/run/config.rs

@@ -112,6 +112,7 @@ mod tests {
             mode: RunnerMode::Instrumentation,
             instruments: vec![],
             mongo_uri_env_name: None,
+            message_format: None,
             skip_upload: false,
             skip_setup: false,
             command: vec!["cargo".into(), "codspeed".into(), "bench".into()],
@@ -138,6 +139,7 @@ mod tests {
             mode: RunnerMode::Instrumentation,
             instruments: vec!["mongodb".into()],
             mongo_uri_env_name: Some("MONGODB_URI".into()),
+            message_format: Some("json".into()),
             skip_upload: true,
             skip_setup: true,
             command: vec!["cargo".into(), "codspeed".into(), "bench".into()],

src/run/mod.rs

@@ -87,6 +87,9 @@ pub struct RunArgs {
     #[arg(long)]
     pub mongo_uri_env_name: Option<String>,
 
+    #[arg(long)]
+    pub message_format: Option<String>,
+
     /// Only for debugging purposes, skips the upload of the results
     #[arg(
         long,
@@ -117,6 +120,7 @@ impl RunArgs {
             mode: RunnerMode::Instrumentation,
             instruments: vec![],
             mongo_uri_env_name: None,
+            message_format: None,
             skip_upload: false,
             skip_setup: false,
             command: vec![],
@@ -125,6 +129,12 @@ impl RunArgs {
 }
 
 pub async fn run(args: RunArgs, api_client: &CodSpeedAPIClient) -> Result<()> {
+    let output_json = args
+        .message_format
+        .as_ref()
+        .map(|format| format == "json")
+        .unwrap_or(false);
+
     let mut config = Config::try_from(args)?;
     let provider = run_environment::get_provider(&config)?;
     let codspeed_config = CodSpeedConfig::load()?;
@@ -194,7 +204,15 @@ pub async fn run(args: RunArgs, api_client: &CodSpeedAPIClient) -> Result<()> {
 
         if provider.get_run_environment() == RunEnvironment::Local {
             start_group!("Fetching the results");
+            let run_id = upload_result.run_id.clone();
             poll_results::poll_results(api_client, &provider, upload_result.run_id).await?;
+            if output_json {
+                // TODO: Refactor `log_json` to accept a serde_json::Value arguemnt
+                log_json!(format!(
+                    "{{\"event\": \"run_finished\", \"run_id\": \"{}\"}}",
+                    run_id
+                ));
+            }
             end_group!();
         }
     }