env: Add DVCLIVE_OPEN

Use in `live` for optionally disable opening a web
browser on HTML generation background task.

Defaults True.

Closes iterative/dvclive#201

dvc/env.py

@@ -5,6 +5,7 @@
 DVCLIVE_PATH = "DVCLIVE_PATH"
 DVCLIVE_SUMMARY = "DVCLIVE_SUMMARY"
 DVCLIVE_HTML = "DVCLIVE_HTML"
+DVCLIVE_OPEN = "DVCLIVE_OPEN"
 DVCLIVE_RESUME = "DVCLIVE_RESUME"
 DVC_IGNORE_ISATTY = "DVC_IGNORE_ISATTY"
 DVC_EXP_GIT_REMOTE = "DVC_EXP_GIT_REMOTE"

dvc/repo/live.py

@@ -1,8 +1,10 @@
 import logging
+import os
 from typing import TYPE_CHECKING, List, Optional
 
 from funcy import once_per_args
 
+from dvc.env import DVCLIVE_OPEN
 from dvc.render.utils import match_renderers, render
 
 logger = logging.getLogger(__name__)
@@ -20,7 +22,6 @@ def webbrowser_open(url: str) -> int:
 
 
 def create_summary(out):
-
     assert out.live and out.live["html"]
 
     metrics, plots = out.repo.live.show(out.fs_path)
@@ -31,8 +32,9 @@ def create_summary(out):
     index_path = render(
         out.repo, renderers, metrics=metrics, path=html_path, refresh_seconds=5
     )
-
-    webbrowser_open(index_path)
+    auto_open = out.repo.config["plots"].get("auto_open", False)
+    if auto_open and int(os.environ.get(DVCLIVE_OPEN, "1")):
+        webbrowser_open(index_path)
 
 
 def summary_fs_path(out: "Output") -> Optional[str]:

tests/func/test_live.py

@@ -241,7 +241,15 @@ def test_live_checkpoints_resume(
     assert checkpoints_metric(results, "logs.json", "metric2") == [8, 6, 4, 2]
 
 
-def test_dvc_generates_html_during_run(tmp_dir, dvc, mocker, live_stage):
+@pytest.mark.parametrize("auto_open", [False, True])
+def test_dvc_generates_html_during_run(
+    tmp_dir, dvc, mocker, live_stage, auto_open
+):
+    if auto_open:
+        with dvc.config.edit() as conf:
+            conf["plots"]["auto_open"] = True
+    else:
+        mocker.patch.dict(os.environ, {"DVCLIVE_OPEN": "0"})
     show_spy = mocker.spy(dvc.live, "show")
     webbrowser_open = mocker.patch("dvc.repo.live.webbrowser_open")
 
@@ -265,7 +273,7 @@ def test_dvc_generates_html_during_run(tmp_dir, dvc, mocker, live_stage):
     live_stage(summary=True, live="logs", code=script)
 
     assert show_spy.call_count == 2
-    assert webbrowser_open.call_count == 2
+    assert webbrowser_open.call_count == (2 if auto_open else 0)
 
 
 def test_dvclive_stage_with_different_wdir(tmp_dir, scm, dvc):