Cylc reg tweak.

bin/cylc-register

@@ -22,8 +22,9 @@ Register the name REG for the suite definition in PATH. The suite server
 program can then be started, stopped, and targeted by name REG. (Note that
 "cylc run" can also register suites on the fly).
 
-Registration creates a suite run directory "~/cylc-run/REG/" with a ".service/"
-sub-directory containing authentication files and a "source" symlink to PATH.
+Registration creates a suite run directory "~/cylc-run/REG/" containing a
+".service/source" symlink to the suite definition PATH. The .service directory
+will also be used for server authentication files at run time.
 
 Suite names can be hierarchical, corresponding to the path under ~/cylc-run.
 

lib/cylc/scheduler_cli.py

@@ -85,8 +85,11 @@ def main(is_restart=False):
     options, args = parse_commandline(is_restart)
     if not args:
         # Auto-registration: "cylc run" (no args) in source dir.
-        reg = SuiteSrvFilesManager().register()
-        # Replace this process with "cylc run REG ..." for easy identification.
+        try:
+            reg = SuiteSrvFilesManager().register()
+        except SuiteServiceFileError as exc:
+            sys.exit(exc)
+        # Replace this process with "cylc run REG ..." for 'ps -f'.
         os.execv(sys.argv[0], [sys.argv[0]] + [reg] + sys.argv[1:])
 
     # Check suite is not already running before start of host selection.

lib/cylc/suite_srv_files_mgr.py

@@ -431,59 +431,55 @@ def register(self, reg=None, source=None, redirect=False):
                 Another suite already has this name (unless --redirect).
         """
         if reg is None:
-            # Take name of parent dir as suite name.
             reg = os.path.basename(os.getcwd())
 
         if os.path.isabs(reg):
             raise SuiteServiceFileError(
                 "ERROR: suite name cannot be an absolute path: %s" % reg)
 
-        # Suite service directory.
-        srv_d = self.get_suite_srv_dir(reg)
-
-        # Check if reg is already used.
-        target = os.path.join(srv_d, self.FILE_BASE_SOURCE)
-        try:
-            # Already used?
-            orig_source = os.readlink(target)
-        except OSError:
-            orig_source = None
-
         if source is not None:
-            # Regularize: want suite dir name only (not dir/suite.rc).
             if os.path.basename(source) == self.FILE_BASE_SUITE_RC:
                 source = os.path.dirname(source)
         else:
-            # Assume source is $PWD unless reg is already used.
-            if orig_source is None:
-                source = os.getcwd()
-            else:
-                source = orig_source
+            source = os.getcwd()
 
         # suite.rc must exist so we can detect accidentally reversed args.
         source = os.path.abspath(source)
         if not os.path.isfile(os.path.join(source, self.FILE_BASE_SUITE_RC)):
             raise SuiteServiceFileError("ERROR: no suite.rc in %s" % source)
 
-        if orig_source is None:
-            mkdir_p(srv_d)
-            os.symlink(source, target)
+        # Suite service directory.
+        srv_d = self.get_suite_srv_dir(reg)
 
-        elif orig_source != source:
-            # Redirecting an existing name and run directory to another suite.
+        # Does symlink to suite source already exist?
+        target = os.path.join(srv_d, self.FILE_BASE_SOURCE)
+        try:
+            orig_source = os.readlink(target)
+        except OSError:
+            orig_source = None
+
+        # Create service dir if necessary.
+        mkdir_p(srv_d)
+
+        # Redirect an existing name to another suite?
+        if orig_source is not None and source != orig_source:
             if not redirect:
                 raise SuiteServiceFileError(
-                    "ERROR: the suite name '%s' is already used for %s." % (
-                        reg, orig_source))
-            else:
-                sys.stderr.write(
-                    "WARNING: the suite name '%s' was used for %s.\n"
-                    "The run directory will be reused for %s.\n" % (
-                        reg, orig_source, source))
+                    "ERROR: the name '%s' already points to %s.\nUse "
+                    "--redirect to re-use an existing name and run "
+                    "directory." % (reg, orig_source))
+            sys.stderr.write(
+                "WARNING: the name '%(reg)s' points to %(old)s.\nIt will now"
+                " be redirected to %(new)s.\nFiles in the existing %(reg)s run"
+                " directory will be overwritten.\n" % {
+                    'reg': reg, 'old': orig_source, 'new': source})
+            # Remove symlink to the original suite.
             os.unlink(target)
+
+        # Create symlink to the suite, if it doesn't already exist.
+        if source != orig_source:
             os.symlink(source, target)
 
-        # Report the new (or renewed) registration.
         print 'REGISTERED %s -> %s' % (reg, source)
         return reg
 

tests/registration/00-simple.t

@@ -83,16 +83,18 @@ run_ok "${TEST_NAME}" cylc register $CHEESE $CHEESE
 TEST_NAME="${TEST_NAME_BASE}-repurpose1"
 run_fail "${TEST_NAME}" cylc register $CHEESE $YOGHURT
 contains_ok "${TEST_NAME}.stderr" <<__ERR__
-ERROR: the suite name '$CHEESE' is already used for ${PWD}/$CHEESE.
+ERROR: the name '$CHEESE' already points to ${PWD}/$CHEESE.
+Use --redirect to re-use an existing name and run directory.
 __ERR__
 
 # Test succeed "cylc reg REG PATH" where REG already points to PATH2
 TEST_NAME="${TEST_NAME_BASE}-repurpose2"
 cp -r $CHEESE $YOGHURT
 run_ok "${TEST_NAME}" cylc register --redirect $CHEESE $YOGHURT
 contains_ok "${TEST_NAME}.stderr" <<__ERR__
-WARNING: the suite name '$CHEESE' was used for ${PWD}/$CHEESE.
-The run directory will be reused for ${PWD}/$YOGHURT.
+WARNING: the name '$CHEESE' points to ${PWD}/$CHEESE.
+It will now be redirected to ${PWD}/$YOGHURT.
+Files in the existing $CHEESE run directory will be overwritten.
 __ERR__
 contains_ok "${TEST_NAME}.stdout" <<__OUT__
 REGISTERED $CHEESE -> ${PWD}/$YOGHURT