Merge "Fork off a custom workspace_status.py with more heuristics" into stable-3.1

1 files changed, 195 insertions, 0 deletions

diff --git a/tools/workspace_status_release.py b/tools/workspace_status_release.py
new file mode 100644
index 0000000000..36535fb70f
--- /dev/null
+++ b/tools/workspace_status_release.py
@@ -0,0 +1,195 @@
+#!/usr/bin/env python
+
+# This is a variant of the `workspace_status.py` script that in addition to
+# plain `git describe` implements a few heuristics to arrive at more to the
+# point stamps for directories. But due to the implemented heuristics, it will
+# typically take longer to run (especially if you use lots of plugins that
+# come without tags) and might slow down your development cycle when used
+# as default.
+#
+# To use it, simply add
+#
+#   --workspace_status_command="python ./tools/workspace_status_release.py"
+#
+# to your bazel command. So for example instead of
+#
+#   bazel build release.war
+#
+# use
+#
+#   bazel build --workspace_status_command="python ./tools/workspace_status_release.py" release.war
+#
+# Alternatively, you can add
+#
+#   build --workspace_status_command="python ./tools/workspace_status_release.py"
+#
+# to `.bazelrc` in your home directory.
+#
+# If the script exits with non-zero code, it's considered as a failure
+# and the output will be discarded.
+
+from __future__ import print_function
+import os
+import subprocess
+import sys
+import re
+
+ROOT = os.path.abspath(__file__)
+while not os.path.exists(os.path.join(ROOT, 'WORKSPACE')):
+    ROOT = os.path.dirname(ROOT)
+REVISION_CMD = ['git', 'describe', '--always', '--dirty']
+
+
+def run(command):
+    try:
+        return subprocess.check_output(command).strip().decode("utf-8")
+    except OSError as err:
+        print('could not invoke %s: %s' % (command[0], err), file=sys.stderr)
+        sys.exit(1)
+    except subprocess.CalledProcessError:
+        # ignore "not a git repository error" to report unknown version
+        return None
+
+
+def revision_with_match(pattern=None, prefix=False, all_refs=False,
+                        return_unmatched=False):
+    """Return a description of the current commit
+
+    Keyword arguments:
+    pattern    -- (Default: None) Use only refs that match this pattern.
+    prefix     -- (Default: False) If True, the pattern is considered a prefix
+                  and does not require an exact match.
+    all_refs   -- (Default: False) If True, consider all refs, not just tags.
+    return_unmatched -- (Default: False) If False and a pattern is given that
+                  cannot be matched, return the empty string. If True, return
+                  the unmatched description nonetheless.
+    """
+
+    command = REVISION_CMD[:]
+    if pattern:
+        command += ['--match', pattern + ('*' if prefix else '')]
+    if all_refs:
+        command += ['--all', '--long']
+
+    description = run(command)
+
+    if pattern and not return_unmatched and not description.startswith(pattern):
+        return ''
+    return description
+
+
+def branch_with_match(pattern):
+    for ref_kind in ['origin/', 'gerrit/', '']:
+        description = revision_with_match(ref_kind + pattern, all_refs=True,
+                                          return_unmatched=True)
+        for cutoff in ['heads/', 'remotes/', ref_kind]:
+            if description.startswith(cutoff):
+                description = description[len(cutoff):]
+        if description.startswith(pattern):
+            return description
+    return ''
+
+
+def revision(template=None):
+    if template:
+        # We use the version `v2.16.19-1-gec686a6352` as running example for the
+        # below comments. First, we split into ['v2', '16', '19']
+        parts = template.split('-')[0].split('.')
+
+        # Although we have releases with version tags containing 4 numbers, we
+        # treat only the first three numbers for simplicity. See discussion on
+        # Ib1681b2730cf2c443a3cb55fe6e282f6484e18de.
+
+        if len(parts) >= 3:
+            # Match for v2.16.19
+            version_part = '.'.join(parts[0:3])
+            description = revision_with_match(version_part)
+            if description:
+                return description
+
+        if len(parts) >= 2:
+            version_part = '.'.join(parts[0:2])
+
+            # Match for v2.16.*
+            description = revision_with_match(version_part + '.', prefix=True)
+            if description:
+                return description
+
+            # Match for v2.16
+            description = revision_with_match(version_part)
+            if description.startswith(version_part):
+                return description
+
+            if template.startswith('v'):
+                # Match for stable-2.16 branches
+                branch = 'stable-' + version_part[1:]
+                description = branch_with_match(branch)
+                if description:
+                    return description
+
+    # None of the template based methods worked out, so we're falling back to
+    # generic matches.
+
+    # Match for master branch
+    description = branch_with_match('master')
+    if description:
+        return description
+
+    # Match for anything that looks like a version tag
+    description = revision_with_match('v[0-9].', return_unmatched=True)
+    if description.startswith('v'):
+        return description
+
+    # Still no good tag, so we re-try without any matching
+    return revision_with_match()
+
+
+# prints the stamps for the current working directory
+def print_stamps_for_cwd(name, template):
+    workspace_status_script = os.path.join(
+        'tools', 'workspace_status_release.py')
+    if os.path.isfile(workspace_status_script):
+        # directory has own workspace_status_command, so we use stamps from that
+        for line in run(["python", workspace_status_script]).split('\n'):
+            if re.search("^STABLE_[a-zA-Z0-9().:@/_ -]*$", line):
+                print(line)
+    else:
+        # directory lacks own workspace_status_command, so we create a default
+        # stamp
+        v = revision(template)
+        print('STABLE_BUILD_%s_LABEL %s' % (name.upper(),
+                                            v if v else 'unknown'))
+
+
+# os.chdir is different from plain `cd` in shells in that it follows symlinks
+# and does not update the PWD environment. So when using os.chdir to change into
+# a symlinked directory from gerrit's `plugins` or `modules` directory, we
+# cannot recover gerrit's directory. This prevents the plugins'/modules'
+# `workspace_status_release.py` scripts to detect the name they were symlinked
+# as (E.g.: it-* plugins sometimes get linked in more than once under different
+# names) and to detect gerrit's root directory. To work around this problem, we
+# mimic the `cd` of ordinary shells. By using this function, symlink information
+# is preserved in the `PWD` environment variable (as it is for example also done
+# in bash) and plugin/module `workspace_status_release.py` scripts can pick up
+# the needed information from there.
+def cd(absolute_path):
+    os.environ['PWD'] = absolute_path
+    os.chdir(absolute_path)
+
+
+def print_stamps():
+    cd(ROOT)
+    gerrit_version = revision()
+    print("STABLE_BUILD_GERRIT_LABEL %s" % gerrit_version)
+    for kind in ['modules', 'plugins']:
+        kind_dir = os.path.join(ROOT, kind)
+        for d in os.listdir(kind_dir) if os.path.isdir(kind_dir) else []:
+            p = os.path.join(kind_dir, d)
+            if os.path.isdir(p):
+                cd(p)
+                name = os.path.basename(p)
+                print_stamps_for_cwd(name, gerrit_version)
+
+
+if __name__ == '__main__':
+    print_stamps()