add: Allow 0 in group limits for unlimited parallel tasks

CHANGELOG.md

@@ -8,8 +8,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 ### Added
 
-- Support modification of task priorities via `pueue edit --priority/-o` and `pueue restart --edit-priority/-o` [#449](https://github.com/Nukesor/pueue/issues/449)
+- Support modification of task priorities via `pueue edit --priority/-o` and `pueue restart --edit-priority/-o` [#449](https://github.com/Nukesor/pueue/issues/449).
 - If no output directory is provided in `completions`, the generated file is printed to `stdout` [#489](https://github.com/Nukesor/pueue/issues/489).
+- Allow setting the `parallel_tasks` value of groups to `0`. Setting this value allows unlimited tasks for that group [#500](https://github.com/Nukesor/pueue/issues/500).
 
 ### Fixed
 

pueue/src/client/cli.rs

@@ -477,7 +477,7 @@ https://github.com/Nukesor/pueue/issues/350#issue-1359083118"
             This limit is only considered when tasks are scheduled.")]
     Parallel {
         /// The amount of allowed parallel tasks.
-        #[arg(value_parser = min_one)]
+        /// Setting this to 0 means an unlimited amount of parallel tasks.
         parallel_tasks: Option<usize>,
 
         /// Set the amount for a specific group.
@@ -504,7 +504,8 @@ pub enum GroupCommand {
         name: String,
 
         /// Set the amount of parallel tasks this group can have.
-        #[arg(short, long, value_parser = min_one)]
+        /// Setting this to 0 means an unlimited amount of parallel tasks.
+        #[arg(short, long)]
         parallel: Option<usize>,
     },
 
@@ -573,16 +574,3 @@ fn parse_delay_until(src: &str) -> Result<DateTime<Local>, String> {
         "could not parse as seconds or date expression",
     ))
 }
-
-/// Validator function. The input string has to be parsable as int and bigger than 0
-fn min_one(value: &str) -> Result<usize, String> {
-    match value.parse::<usize>() {
-        Ok(value) => {
-            if value < 1 {
-                return Err("You must provide a value that's bigger than 0".into());
-            }
-            Ok(value)
-        }
-        Err(_) => Err("Failed to parse integer".into()),
-    }
-}

pueue/src/daemon/task_handler/spawn_task.rs

@@ -49,6 +49,12 @@ impl TaskHandler {
                     return false;
                 }
 
+                // If parallel tasks are set to `0`, this means an unlimited amount of tasks may
+                // run at any given time.
+                if group.parallel_tasks == 0 {
+                    return true;
+                }
+
                 // Get the currently running tasks by looking at the actually running processes.
                 // They're sorted by group, which makes this quite convenient.
                 let running_tasks = match self.children.0.get(&task.group) {

pueue/tests/daemon/integration/parallel_tasks.rs

@@ -1,7 +1,7 @@
 use anyhow::Result;
 use pretty_assertions::assert_eq;
 
-use pueue_lib::task::*;
+use pueue_lib::{network::message::ParallelMessage, task::*};
 
 use crate::helper::*;
 
@@ -56,3 +56,34 @@ async fn test_parallel_tasks() -> Result<()> {
     }
     Ok(())
 }
+
+/// Test that a group with a parallel limit of `0` has an unlimited amount of tasks.
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn test_unlimited_parallel_tasks() -> Result<()> {
+    let daemon = daemon().await?;
+    let shared = &daemon.settings.shared;
+
+    // Add a new group with 1 slot
+    add_group_with_slots(shared, "testgroup", 1).await?;
+
+    // Add 10 long running tasks to this group, only 1 should be immediately started.
+    for _ in 0..10 {
+        assert_success(add_task_to_group(shared, "sleep 600", "testgroup").await?);
+    }
+    // Ensure the first tasks is started.
+    wait_for_task_condition(shared, 0, |task| task.is_running()).await?;
+
+    // Update the parallel limit of the group to 0
+    let message = ParallelMessage {
+        group: "testgroup".to_string(),
+        parallel_tasks: 0,
+    };
+    assert_success(send_message(shared, message).await?);
+
+    // Make sure all other tasks are started as well in quick succession.
+    for task_id in 1..10 {
+        wait_for_task_condition(shared, task_id, |task| task.is_running()).await?;
+    }
+
+    Ok(())
+}