Open source load generator (#35772)

## Description
Move load_generator, backend_harness, health_check, log_interleaver, performance_stats, big_brain_client, and big_brain_private_api_types from crates_private to crates directory.

Update all references in Cargo.toml files to point to the new locations.

## Testing
Verified with lint-rust that all license issues are fixed and dependencies are correctly updated.

Link to Devin run: https://app.devin.ai/sessions/a55322e782f049d9a8ba5bc89265ecd2
Co-Authored-By: nipunn@convex.dev
GitOrigin-RevId: 3d1bd23d9bc79965adf3c42a52c70a16c097a833

Author: devin-ai-integration[bot]

Cargo.lock

@@ -22,6 +22,7 @@ aws-smithy-http = "0.60.8"
 aws-types = "1.1"
 axum = { version = "0.8", features = [ "ws", "original-uri", "macros", "multipart" ] }
 axum-extra = { version = "0.10", features = [ "typed-header", "cookie" ] }
+backoff = { version = "0.4", features = [ "tokio" ] }
 base32 = "0.5.0"
 base-62 = { rev = "6f91a3da4b83f20379469835f64195bd52d7b9dd", git = "https://github.com/kryptco/base62.rs" }
 base64 = "0.13"
@@ -39,6 +40,7 @@ criterion = "0.5"
 crossbeam-channel = "0.5"
 csf = "0.1.11"
 cstr = "0.2.11"
+ctrlc = "3.4"
 deadpool-postgres = "^0.14.0"
 deno_core = "0.284.0"
 deno_core_icudata = "0.73.0"
@@ -76,6 +78,9 @@ hyper-util = { version = "0.1.5", features = [ "server-graceful", "tokio" ] }
 proc-macro2 = { version = "1.0" }
 imbl = "5.0.0"
 itertools = "0.14"
+tikv-jemallocator = { version = "0.6", features = [ "profiling", "unprefixed_malloc_on_supported_platforms" ] }
+tikv-jemalloc-sys = { version = "0.6", features = [ "profiling", "unprefixed_malloc_on_supported_platforms" ] }
+jemalloc_pprof = "0.6"
 jsonschema = "0.28"
 levenshtein_automata = "0.2.1"
 libc = "0.2"
@@ -143,6 +148,7 @@ syn = { version = "2.0", features = [ "full" ] }
 tantivy = { git = "https://github.com/get-convex/tantivy", rev = "c745b0977df94bc22fe4fc75db0200a8023f9a2c" }
 tantivy-common = { git = "https://github.com/get-convex/tantivy", rev = "c745b0977df94bc22fe4fc75db0200a8023f9a2c" }
 tempfile = "3"
+textplots = "0.8"
 thiserror = "2"
 thousands = "0.2.0"
 tld = "2.36.0"

Cargo.toml

@@ -0,0 +1,33 @@
+[package]
+name = "backend_harness"
+version = "0.1.0"
+edition = "2021"
+license = "LicenseRef-FSL-1.1-Apache-2.0"
+
+[lib]
+doctest = false
+
+[dependencies]
+anyhow = { workspace = true }
+backoff = { workspace = true }
+big_brain_client = { path = "../../crates/big_brain_client" }
+big_brain_private_api_types = { path = "../../crates/big_brain_private_api_types" }
+clap = { workspace = true }
+cmd_util = { path = "../../crates/cmd_util" }
+crossbeam-channel = { workspace = true }
+ctrlc = { workspace = true }
+dotenvy = { workspace = true }
+futures = { workspace = true }
+health_check = { path = "../../crates/health_check" }
+home = { workspace = true }
+keybroker = { path = "../../crates/keybroker" }
+log_interleaver = { path = "../../crates/log_interleaver" }
+metrics = { path = "../../crates/metrics" }
+serde = { workspace = true }
+serde_json = { workspace = true }
+tempfile = { workspace = true }
+tokio = { workspace = true }
+tracing = { workspace = true }
+
+[lints]
+workspace = true

crates/backend_harness/Cargo.toml

@@ -0,0 +1,7 @@
+Backend Harness library which provides methods that spin up / spin down a
+backend for testing. Supports production backends and local process backends.
+
+Other scripts can use the backend-harness library to manage backend coming up /
+going down (eg load tester)
+
+There's a small binary included to show off how to use backend-harness

crates/backend_harness/README.md

@@ -0,0 +1,72 @@
+#![feature(exit_status_error)]
+use std::path::PathBuf;
+
+use backend_harness::{
+    with_provision,
+    BackendProvisioner,
+    ProvisionRequest,
+};
+use clap::Parser;
+use cmd_util::env::config_tool;
+use log_interleaver::LogInterleaver;
+use metrics::StaticMetricLabel;
+use tokio::process::Command;
+
+/// Run the command while a backend is provisioned.
+#[derive(Parser, Debug)]
+struct Args {
+    /// Provisioner
+    #[clap(long, value_enum)]
+    provisioner: BackendProvisioner,
+
+    /// Path under which to provision backend
+    #[clap(long)]
+    package_dir: PathBuf,
+
+    /// Command to run while backend is provisioned
+    cmd: Vec<String>,
+}
+
+#[tokio::main]
+async fn main() -> anyhow::Result<()> {
+    let _guard = config_tool();
+    let Args {
+        provisioner,
+        package_dir,
+        cmd,
+    } = Args::parse();
+    let logs = LogInterleaver::new();
+
+    let (tx, rx) = crossbeam_channel::bounded(1);
+    if cmd.is_empty() {
+        ctrlc::set_handler(move || {
+            tx.send(()).unwrap();
+        })?;
+    }
+
+    with_provision(
+        &logs.clone(),
+        provisioner,
+        &ProvisionRequest::NewProject,
+        &package_dir,
+        StaticMetricLabel::new("load_description", "backend-harness"),
+        |host, _, _| async move {
+            if cmd.is_empty() {
+                println!("Provisioned {host}. Ctrl-C to quit");
+                rx.recv()?;
+                println!("Cleaning up {host}");
+            } else {
+                Command::new(cmd[0].clone())
+                    .args(&cmd[1..])
+                    .spawn()?
+                    .wait()
+                    .await?
+                    .exit_ok()?;
+            }
+            Ok(())
+        },
+    )
+    .await?;
+
+    Ok(())
+}

crates/backend_harness/src/bin/backend-harness.rs

@@ -0,0 +1,15 @@
+#![feature(exit_status_error)]
+#![feature(try_blocks)]
+
+/// Harness for spawning/testing a backend for a given package
+mod metrics;
+mod provision;
+
+pub use provision::{
+    get_cli_version,
+    get_configured_deployment_name,
+    with_provision,
+    BackendProvisioner,
+    ProvisionHostCredentials,
+    ProvisionRequest,
+};

crates/backend_harness/src/lib.rs

@@ -0,0 +1,59 @@
+use metrics::{
+    log_counter_with_labels,
+    register_convex_counter,
+    StaticMetricLabel,
+};
+
+use crate::ProvisionRequest;
+
+register_convex_counter!(
+    PROVISIONS_TOTAL,
+    "Number of provisions",
+    &["status", "load_description", "provision_type"]
+);
+pub fn log_provision(
+    metric_label: StaticMetricLabel,
+    is_ok: bool,
+    provision_type: &ProvisionRequest,
+) {
+    let provision_type_label = match provision_type {
+        ProvisionRequest::ExistingProject { .. } => "existing_project",
+        ProvisionRequest::NewProject => "new_project",
+        ProvisionRequest::Preview { .. } => "preview",
+    };
+    log_counter_with_labels(
+        &PROVISIONS_TOTAL,
+        1,
+        vec![
+            metric_label,
+            StaticMetricLabel::status(is_ok),
+            StaticMetricLabel::new("provision_type", provision_type_label),
+        ],
+    );
+}
+
+register_convex_counter!(
+    DEACTIVATES_TOTAL,
+    "Number of deactivates",
+    &["status", "load_description"]
+);
+pub fn log_deactivate(metric_label: StaticMetricLabel, is_ok: bool) {
+    log_counter_with_labels(
+        &DEACTIVATES_TOTAL,
+        1,
+        vec![metric_label, StaticMetricLabel::status(is_ok)],
+    );
+}
+
+register_convex_counter!(
+    PUSH_TOTAL,
+    "Number of pushes",
+    &["status", "load_description"]
+);
+pub fn log_push(metric_label: StaticMetricLabel, is_ok: bool) {
+    log_counter_with_labels(
+        &PUSH_TOTAL,
+        1,
+        vec![metric_label, StaticMetricLabel::status(is_ok)],
+    );
+}