Merge pull request #7 from mrc-ide/mrc-6198

Add task info function

src/hipercow/task.py

@@ -40,13 +40,30 @@ def __str__(self) -> str:
 @dataclass
 class TaskTimes:
     created: float
-    started: float
-    finished: float
+    started: float | None
+    finished: float | None
 
     def write(self, root: Root, task_id: str):
         with root.path_task_times(task_id).open("wb") as f:
             pickle.dump(self, f)
 
+    @staticmethod
+    def read(root: Root, task_id: str):
+        path_times = root.path_task_times(task_id)
+        if path_times.exists():
+            with path_times.open("rb") as f:
+                return pickle.load(f)
+        created = root.path_task_data(task_id).stat().st_ctime
+        path_task_running = (
+            root.path_task(task_id) / STATUS_FILE_MAP[TaskStatus.RUNNING]
+        )
+        running = (
+            path_task_running.stat().st_ctime
+            if path_task_running.exists()
+            else None
+        )
+        return TaskTimes(created, running, None)
+
 
 def task_status(root: Root, task_id: str) -> TaskStatus:
     # check_task_id(task_id)
@@ -100,3 +117,20 @@ def task_data_write(root: Root, data: TaskData) -> None:
 def task_data_read(root: Root, task_id: str) -> TaskData:
     with root.path_task_data(task_id).open("rb") as f:
         return pickle.load(f)
+
+
+@dataclass
+class TaskInfo:
+    status: TaskStatus
+    data: TaskData
+    times: TaskTimes
+
+
+def task_info(root: Root, task_id: str) -> TaskInfo:
+    status = task_status(root, task_id)
+    if status == TaskStatus.MISSING:
+        msg = f"Task '{task_id}' does not exist"
+        raise Exception(msg)
+    data = TaskData.read(root, task_id)
+    times = TaskTimes.read(root, task_id)
+    return TaskInfo(status, data, times)

tests/test_task.py

@@ -2,7 +2,16 @@
 
 from hipercow import root
 from hipercow import task_create as tc
-from hipercow.task import TaskStatus, set_task_status, task_log, task_status
+from hipercow.task import (
+    TaskData,
+    TaskStatus,
+    TaskTimes,
+    set_task_status,
+    task_info,
+    task_log,
+    task_status,
+)
+from hipercow.task_eval import task_eval
 from hipercow.util import transient_working_directory
 
 
@@ -45,3 +54,40 @@ def test_that_missing_tasks_error_on_log_read(tmp_path):
 
 def test_can_convert_to_nice_string():
     assert str(TaskStatus.CREATED) == "created"
+
+
+def test_read_task_info(tmp_path):
+    root.init(tmp_path)
+    r = root.open_root(tmp_path)
+    with transient_working_directory(tmp_path):
+        tid = tc.task_create_shell(["echo", "hello world"])
+    info = task_info(r, tid)
+    assert info.status == TaskStatus.CREATED
+    assert info.data == TaskData.read(r, tid)
+    assert info.times == TaskTimes.read(r, tid)
+    assert isinstance(info.times.created, float)
+    assert info.times.started is None
+    assert info.times.finished is None
+
+
+def test_that_missing_tasks_error_on_task_info(tmp_path):
+    root.init(tmp_path)
+    r = root.open_root(tmp_path)
+    task_id = "a" * 32
+    with pytest.raises(Exception, match="Task '.+' does not exist"):
+        task_info(r, task_id)
+
+
+def test_that_can_read_info_for_completed_task(tmp_path):
+    root.init(tmp_path)
+    r = root.open_root(tmp_path)
+    with transient_working_directory(tmp_path):
+        tid = tc.task_create_shell(["echo", "hello world"])
+        task_eval(r, tid)
+        info = task_info(r, tid)
+    assert info.status == TaskStatus.SUCCESS
+    assert info.data == TaskData.read(r, tid)
+    assert info.times == TaskTimes.read(r, tid)
+    assert isinstance(info.times.created, float)
+    assert isinstance(info.times.started, float)
+    assert isinstance(info.times.finished, float)