_frontend/widget: Add artifact-cas-digest show format

This adds the artifact-cas-digest format string to the show command,
allowing to show the CAS digest of the built artifact.

Author: Adrien Plazas

src/buildstream/_frontend/cli.py

@@ -614,6 +614,7 @@ def show(app, elements, deps, except_, order, format_):
         %{build-deps}     A list of build dependencies
         %{runtime-deps}   A list of runtime dependencies
         %{source-info}    Source provenance information
+        %{artifact-cas-digest} The CAS digest of the built artifact
 
     The value of the %{symbol} without the leading '%' character is understood
     as a pythonic formatting string, so python formatting features apply,
@@ -639,7 +640,8 @@ def show(app, elements, deps, except_, order, format_):
         state_match = re.search(r"%(\{(state)[^%]*?\})", format_)
         key_match = re.search(r"%(\{(key)[^%]*?\})", format_)
         full_key_match = re.search(r"%(\{(full-key)[^%]*?\})", format_)
-        need_state = bool(state_match or key_match or full_key_match)
+        artifact_cas_digest_match = re.search(r"%(\{(artifact-cas-digest)[^%]*?\})", format_)
+        need_state = bool(state_match or key_match or full_key_match or artifact_cas_digest_match)
 
         if not elements:
             elements = app.project.get_default_targets()

src/buildstream/_frontend/widget.py

@@ -461,6 +461,20 @@ def show_pipeline(self, dependencies, format_):
                 # Dump the SourceInfo provenance objects in yaml format
                 line = p.fmt_subst(line, "source-info", _yaml.roundtrip_dump_string(all_source_infos))
 
+            # Artifact CAS Digest
+            if "%{artifact-cas-digest" in format_:
+                artifact = element._get_artifact()
+                if artifact.cached():
+                    artifact_files = artifact.get_files()
+                    # We call the private CasBasedDirectory._get_digest() for
+                    # the moment, we should make it public on Directory.
+                    artifact_digest = artifact_files._get_digest()
+                    formated_artifact_digest = "{}/{}".format(artifact_digest.hash, artifact_digest.size_bytes)
+                    line = p.fmt_subst(line, "artifact-cas-digest", formated_artifact_digest)
+                else:
+                    line = p.fmt_subst(line, "artifact-cas-digest", "")
+                    element.warn("Cannot obtain CAS digest because artifact is not cached")
+
             report += line + "\n"
 
         return report.rstrip("\n")

tests/frontend/show_artifact_cas_digest.py

@@ -0,0 +1,238 @@
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+#
+
+# Pylint doesn't play well with fixtures and dependency injection from pytest
+# pylint: disable=redefined-outer-name
+
+import os
+
+import pytest
+
+from buildstream._testing import cli  # pylint: disable=unused-import
+
+from tests.testutils import (
+    create_artifact_share,
+    assert_shared,
+    assert_not_shared,
+)
+
+
+DATA_DIR = os.path.join(os.path.dirname(os.path.realpath(__file__)), "show_artifact_cas_digest_project")
+
+
+# This tests that a target that hasn't been built locally
+# and that isn't cached remotely has not artifact CAS
+# digest.
+#
+# The test is performed without a remote cache.
+#
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize(
+    "target",
+    [
+        "import-basic-files.bst",
+        "import-executable-files.bst",
+        "import-symlinks.bst",
+    ],
+    ids=["basic-files", "executable-files", "symlinks"],
+)
+def test_show_artifact_cas_digest_uncached(cli, tmpdir, datafiles, target):
+    project = str(datafiles)
+    expected_no_digest = ""
+
+    # Check the target has not been built locally and is not existing in the remote cache
+    assert (
+        # May be "buildable" or "waiting" but shouldn't be "cached"
+        cli.get_element_state(project, target) != "cached"
+    )
+
+    # Check the target has no artifact digest
+    result = cli.run(project=project, silent=True, args=["show", "--format", "%{name},%{artifact-cas-digest}", target])
+    result.assert_success()
+
+    received_digest = result.output.splitlines()[0]
+    assert received_digest == "{target},{digest}".format(target=target, digest=expected_no_digest)
+
+
+# This tests that a target that has been built locally and
+# with no remote has an artifact CAS digest.
+#
+# The test is performed without a remote cache.
+#
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize(
+    "target, expected_digest",
+    [
+        ("import-basic-files.bst", "7093d3c89029932ce1518bd2192e1d3cf60fd88e356b39195d10b87b598c78f0/168"),
+        ("import-executable-files.bst", "133a9ae2eda30945a363272ac14bb2c8a941770b5a37c2847c99934f2972ce4f/170"),
+        ("import-symlinks.bst", "95947ea55021e26cec4fd4f9de90d2b7f4f7d803ccc91656b3e1f2c9923ddf19/131"),
+    ],
+    ids=["basic-files", "executable-files", "symlinks"],
+)
+def test_show_artifact_cas_digest_cached(cli, tmpdir, datafiles, target, expected_digest):
+    project = str(datafiles)
+
+    # Build the target locally
+    result = cli.run(project=project, silent=True, args=["build", target])
+    result.assert_success()
+
+    # Check the target has been built locally and is existing in the remote cache
+    assert cli.get_element_state(project, target) == "cached"
+
+    # Check the target has an artifact digest
+    result = cli.run(project=project, silent=True, args=["show", "--format", "%{name},%{artifact-cas-digest}", target])
+    result.assert_success()
+
+    received_digest = result.output.splitlines()[0]
+    assert received_digest == "{target},{digest}".format(target=target, digest=expected_digest)
+
+
+# This tests that the target and its dependencies are built
+# as expected and that all their artifact CAS digests are
+# available.
+#
+# The test is performed without a remote cache.
+#
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize(
+    "target, expected_digests",
+    [
+        (
+            "dependencies.bst",
+            {
+                "dependencies.bst": "7093d3c89029932ce1518bd2192e1d3cf60fd88e356b39195d10b87b598c78f0/168",
+                "import-symlinks.bst": "95947ea55021e26cec4fd4f9de90d2b7f4f7d803ccc91656b3e1f2c9923ddf19/131",
+            }
+        ),
+    ],
+    ids=["dependencies"],
+)
+def test_show_artifact_cas_digest_dependencies(cli, tmpdir, datafiles, target, expected_digests):
+    project = str(datafiles)
+    expected_no_digest = ""
+
+    # Check the target and its dependencies have not been built locally
+    for component in sorted(expected_digests.keys()):
+        assert (
+            # May be "buildable" or "waiting" but shouldn't be "cached"
+            cli.get_element_state(project, component) != "cached"
+        )
+
+    # Check the target and its dependencies have no artifact digest
+    result = cli.run(project=project, silent=True, args=["show", "--format", "%{name},%{artifact-cas-digest}", target])
+    result.assert_success()
+
+    digests = dict(line.split(",", 2) for line in result.output.splitlines())
+    assert len(digests) == len(expected_digests)
+
+    for component, received in sorted(digests.items()):
+        assert received == expected_no_digest
+
+    # Build the target and its dependencies locally
+    result = cli.run(project=project, silent=True, args=["build", target])
+    result.assert_success()
+
+    # Check the target and its dependencies have been built locally
+    for component in sorted(expected_digests.keys()):
+        assert cli.get_element_state(project, component) == "cached"
+
+    # Check the target and its dependencies have an artifact digest
+    result = cli.run(project=project, silent=True, args=["show", "--format", "%{name},%{artifact-cas-digest}", target])
+    result.assert_success()
+
+    digests = dict(line.split(",", 2) for line in result.output.splitlines())
+    assert len(digests) == len(expected_digests)
+
+    for component, received in sorted(digests.items()):
+        assert received == expected_digests[component]
+
+
+# This tests:
+# - that a target that hasn't been built locally and that
+#   isn't cached remotely has no artifact CAS digest,
+# - that a target that has been built locally and that is
+#   cached remotely has an artifact CAS digest,
+# - that a target that hasn't been built locally and that
+#   is cached remotely has no artifact CAS digest.
+#
+# The test is performed with a remote cache, multiple tests
+# are performed at once and on a single element because
+# setting up a share is expensive.
+#
+@pytest.mark.datafiles(DATA_DIR)
+def test_show_artifact_cas_digest_remote(cli, tmpdir, datafiles):
+    project = str(datafiles)
+    target = "import-basic-files.bst"
+    expected_no_digest = ""
+
+    # Configure a local cache
+    local_cache = os.path.join(str(tmpdir), "cache")
+    cli.configure({"cachedir": local_cache})
+
+    with create_artifact_share(os.path.join(str(tmpdir), "artifactshare")) as share:
+
+        cli.configure({"artifacts": {"servers": [{"url": share.repo, "push": True}]}})
+
+        # Test a target cached neither locally or remotely has no digest
+
+        # Check the target has not been built locally and is not existing in the remote cache
+        assert cli.get_element_state(project, target) == "buildable"
+        assert_not_shared(cli, share, project, target)
+
+        # Check the target has no artifact digest
+        result = cli.run(
+            project=project, silent=True, args=["show", "--format", "%{name},%{artifact-cas-digest}", target]
+        )
+        result.assert_success()
+
+        received_digest = result.output.splitlines()[0]
+        assert received_digest == "{target},{digest}".format(target=target, digest=expected_no_digest)
+
+        # Test a target cached locally has a digest
+
+        # Build the target locally and cache it remotely
+        result = cli.run(project=project, silent=True, args=["build", target])
+        result.assert_success()
+
+        # Check the target has been built and shared
+        assert cli.get_element_state(project, target) == "cached"
+        assert_shared(cli, share, project, target)
+
+        # Check the target has an artifact digest
+        result = cli.run(
+            project=project, silent=True, args=["show", "--format", "%{name},%{artifact-cas-digest}", target]
+        )
+        result.assert_success()
+
+        received_digest = result.output.splitlines()[0]
+        assert received_digest != "{target},{digest}".format(target=target, digest=expected_no_digest)
+
+        # Test a target cached remotely but not locally has no digest
+
+        # Delete the locally cached target
+        result = cli.run(project=project, silent=True, args=["artifact", "delete", target])
+        result.assert_success()
+
+        # Check the target has been deleted locally but not remotely
+        assert cli.get_element_state(project, target) == "buildable"
+        assert_shared(cli, share, project, target)
+
+        # Check the target has an artifact digest
+        result = cli.run(
+            project=project, silent=True, args=["show", "--format", "%{name},%{artifact-cas-digest}", target]
+        )
+        result.assert_success()
+
+        received_digest = result.output.splitlines()[0]
+        assert received_digest == "{target},{digest}".format(target=target, digest=expected_no_digest)

tests/frontend/show_artifact_cas_digest_project/elements/dependencies.bst

@@ -0,0 +1,6 @@
+kind: import
+sources:
+- kind: local
+  path: files/basic-files
+depends:
+- import-symlinks.bst

tests/frontend/show_artifact_cas_digest_project/elements/import-basic-files.bst

@@ -0,0 +1,4 @@
+kind: import
+sources:
+- kind: local
+  path: files/basic-files

tests/frontend/show_artifact_cas_digest_project/elements/import-executable-files.bst

@@ -0,0 +1,4 @@
+kind: import
+sources:
+- kind: local
+  path: files/executable-files

tests/frontend/show_artifact_cas_digest_project/elements/import-symlinks.bst

@@ -0,0 +1,4 @@
+kind: import
+sources:
+- kind: local
+  path: files/symlinks

tests/frontend/show_artifact_cas_digest_project/files/basic-files/basicfile

@@ -0,0 +1 @@
+file contents

tests/frontend/show_artifact_cas_digest_project/files/basic-files/basicfolder/subdir-file

@@ -0,0 +1 @@
+file contents