metrics: skip missing metrics silently

dvc/repo/metrics/show.py

@@ -60,19 +60,19 @@ def _read_metrics(repo, metrics, rev):
         if not tree.exists(metric):
             continue
 
-        with tree.open(metric, "r") as fobj:
-            try:
+        try:
+            with tree.open(metric, "r") as fobj:
                 # NOTE this also supports JSON
                 val = yaml.safe_load(fobj)
-            except yaml.YAMLError:
-                logger.debug(
-                    "failed to read '%s' on '%s'", metric, rev, exc_info=True
-                )
-                continue
+        except (FileNotFoundError, yaml.YAMLError):
+            logger.debug(
+                "failed to read '%s' on '%s'", metric, rev, exc_info=True
+            )
+            continue
 
-            val = _extract_metrics(val)
-            if val:
-                res[str(metric)] = val
+        val = _extract_metrics(val)
+        if val:
+            res[str(metric)] = val
 
     return res
 

tests/func/metrics/test_show.py

@@ -4,6 +4,7 @@
 
 from dvc.repo import Repo
 from dvc.repo.metrics.show import NoMetricsError
+from dvc.utils.fs import remove
 
 
 def test_show_empty(dvc):
@@ -93,3 +94,19 @@ def test_show_subrepo_with_preexisting_tags(tmp_dir, scm):
         "workspace": {expected_path: {"foo": 1}},
         "v1": {expected_path: {"foo": 1}},
     }
+
+
+def test_missing_cache(tmp_dir, dvc, run_copy_metrics):
+    tmp_dir.gen("metrics_t.yaml", "1.1")
+    run_copy_metrics(
+        "metrics_t.yaml", "metrics.yaml", metrics=["metrics.yaml"],
+    )
+
+    # This one should be skipped
+    stage = run_copy_metrics(
+        "metrics_t.yaml", "metrics2.yaml", metrics=["metrics2.yaml"],
+    )
+    remove(stage.outs[0].fspath)
+    remove(stage.outs[0].cache_path)
+
+    assert dvc.metrics.show() == {"": {"metrics.yaml": 1.1}}