live: Explicitly require exp for sending Studio updates.

Requires using either `dvc exp run` or `save_dvc_exp=True`.

Closes #474

src/dvclive/live.py

@@ -70,7 +70,7 @@ def __init__(
             self._init_cleanup()
 
         self._baseline_rev: Optional[str] = None
-        self._exp_name: str = "dvclive-exp"
+        self._exp_name: Optional[str] = None
         self._experiment_rev: Optional[str] = None
         self._inside_dvc_exp: bool = False
         self._dvc_repo = None
@@ -146,12 +146,21 @@ def _init_studio(self):
             self._studio_events_to_skip.add("done")
         elif self._dvc_repo is None:
             logger.warning(
-                "Can't send updates to Studio without a DVC Repo."
+                "Can't connect to Studio without a DVC Repo."
                 "\nYou can create a DVC Repo by calling `dvc init`."
             )
             self._studio_events_to_skip.add("start")
             self._studio_events_to_skip.add("data")
             self._studio_events_to_skip.add("done")
+        elif not self._save_dvc_exp:
+            logger.warning(
+                "Can't connect to Studio without creating a DVC experiment."
+                "\nIf you have a DVC Pipeline, run it with `dvc exp run`."
+                "\nIf you are using DVCLive alone, use `save_dvc_exp=True`."
+            )
+            self._studio_events_to_skip.add("start")
+            self._studio_events_to_skip.add("data")
+            self._studio_events_to_skip.add("done")
         else:
             response = post_live_metrics(
                 "start", self._baseline_rev, self._exp_name, "dvclive"

tests/test_dvc.py

@@ -94,15 +94,15 @@ def test_exp_save_on_end(tmp_dir, save, mocked_dvc_repo):
     live.end()
     if save:
         assert live._baseline_rev is not None
-        assert live._exp_name != "dvclive-exp"
+        assert live._exp_name is not None
         mocked_dvc_repo.experiments.save.assert_called_with(
             name=live._exp_name,
             include_untracked=[live.dir],
             force=True,
         )
     else:
         assert live._baseline_rev is not None
-        assert live._exp_name == "dvclive-exp"
+        assert live._exp_name is None
         mocked_dvc_repo.experiments.save.assert_not_called()
 
 
@@ -131,7 +131,7 @@ def test_exp_save_run_on_dvc_repro(tmp_dir, mocker):
         live = Live(save_dvc_exp=True)
         assert live._save_dvc_exp
         assert live._baseline_rev is not None
-        assert live._exp_name != "dvclive-exp"
+        assert live._exp_name is not None
         live.end()
 
     dvc_repo.experiments.save.assert_called_with(

tests/test_frameworks/test_lightning.py

@@ -213,7 +213,7 @@ def test_lightning_val_udpates_to_studio(tmp_dir, mocked_dvc_repo, mocked_studio
     mocked_post, _ = mocked_studio_post
 
     model = ValLitXOR()
-    dvclive_logger = DVCLiveLogger()
+    dvclive_logger = DVCLiveLogger(save_dvc_exp=True)
     trainer = Trainer(
         logger=dvclive_logger,
         max_steps=4,

tests/test_studio.py

@@ -9,7 +9,7 @@
 
 
 def test_post_to_studio(tmp_dir, mocked_dvc_repo, mocked_studio_post):
-    live = Live()
+    live = Live(save_dvc_exp=True)
     live.log_param("fooparam", 1)
 
     dvc_path = Path(live.dvc_file).as_posix()
@@ -25,7 +25,7 @@ def test_post_to_studio(tmp_dir, mocked_dvc_repo, mocked_studio_post):
             "type": "start",
             "repo_url": "STUDIO_REPO_URL",
             "baseline_sha": "f" * 40,
-            "name": "dvclive-exp",
+            "name": live._exp_name,
             "client": "dvclive",
         },
         headers={
@@ -44,7 +44,7 @@ def test_post_to_studio(tmp_dir, mocked_dvc_repo, mocked_studio_post):
             "type": "data",
             "repo_url": "STUDIO_REPO_URL",
             "baseline_sha": "f" * 40,
-            "name": "dvclive-exp",
+            "name": live._exp_name,
             "step": 0,
             "metrics": {metrics_path: {"data": {"step": 0, "foo": 1}}},
             "params": {params_path: {"fooparam": 1}},
@@ -67,7 +67,7 @@ def test_post_to_studio(tmp_dir, mocked_dvc_repo, mocked_studio_post):
             "type": "data",
             "repo_url": "STUDIO_REPO_URL",
             "baseline_sha": "f" * 40,
-            "name": "dvclive-exp",
+            "name": live._exp_name,
             "step": 1,
             "metrics": {metrics_path: {"data": {"step": 1, "foo": 2}}},
             "params": {params_path: {"fooparam": 1}},
@@ -88,7 +88,7 @@ def test_post_to_studio(tmp_dir, mocked_dvc_repo, mocked_studio_post):
             "type": "done",
             "repo_url": "STUDIO_REPO_URL",
             "baseline_sha": "f" * 40,
-            "name": "dvclive-exp",
+            "name": live._exp_name,
             "client": "dvclive",
         },
         headers={
@@ -104,7 +104,7 @@ def test_post_to_studio_failed_data_request(
 ):
     mocked_post, valid_response = mocked_studio_post
 
-    live = Live()
+    live = Live(save_dvc_exp=True)
 
     dvc_path = Path(live.dvc_file).as_posix()
     metrics_path = Path(live.metrics_file).as_posix()
@@ -125,7 +125,7 @@ def test_post_to_studio_failed_data_request(
             "type": "data",
             "repo_url": "STUDIO_REPO_URL",
             "baseline_sha": "f" * 40,
-            "name": "dvclive-exp",
+            "name": live._exp_name,
             "step": 1,
             "metrics": {metrics_path: {"data": {"step": 1, "foo": 2}}},
             "plots": {
@@ -153,7 +153,7 @@ def test_post_to_studio_failed_start_request(
     mocked_response.status_code = 400
     mocked_post = mocker.patch("requests.post", return_value=mocked_response)
 
-    live = Live()
+    live = Live(save_dvc_exp=True)
 
     live.log_metric("foo", 1)
     live.next_step()
@@ -166,7 +166,7 @@ def test_post_to_studio_failed_start_request(
 
 def test_post_to_studio_end_only_once(tmp_dir, mocked_dvc_repo, mocked_studio_post):
     mocked_post, _ = mocked_studio_post
-    with Live() as live:
+    with Live(save_dvc_exp=True) as live:
         live.log_metric("foo", 1)
         live.next_step()
 
@@ -245,7 +245,7 @@ def test_post_to_studio_include_prefix_if_needed(
 def test_post_to_studio_shorten_names(tmp_dir, mocked_dvc_repo, mocked_studio_post):
     mocked_post, _ = mocked_studio_post
 
-    live = Live()
+    live = Live(save_dvc_exp=True)
     live.log_metric("eval/loss", 1)
     live.next_step()
 
@@ -299,7 +299,7 @@ def test_post_to_studio_inside_subdir(
     subdir.mkdir()
     monkeypatch.chdir(subdir)
 
-    live = Live()
+    live = Live(save_dvc_exp=True)
     live.log_metric("foo", 1)
     live.next_step()
 
@@ -373,3 +373,8 @@ def test_post_to_studio_inside_subdir_dvc_exp(
         },
         timeout=5,
     )
+
+
+def test_post_to_studio_requires_exp(tmp_dir, mocked_dvc_repo, mocked_studio_post):
+    assert Live()._studio_events_to_skip == {"start", "data", "done"}
+    assert not Live(save_dvc_exp=True)._studio_events_to_skip