teuthology/suite: merge base_config with other fragments

Presently the code tries to merge the base_config when the worker starts
running. There's no need to construct it this way and it prevents sharing the
"defaults" with the fragment merging infrastructure. It also prevents
overriding defaults like:

    kernel
        branch: wip-pdonnell-i66704
        client:
            branch: wip-pdonnell-i66704
            flavor: default
            kdb: 1
            sha1: 745cacd8f31e50d7f3b6039bbd8c9a8dfc07bf03
        flavor: default
        kdb: 1
        sha1: 745cacd8f31e50d7f3b6039bbd8c9a8dfc07bf03

A YAML fragment set kernel.client but it cannot delete the changes to
kernel.(branch|flavor|kdb|sha1) because there's no way to remove YAML elements
via a deep merge.

Signed-off-by: Patrick Donnelly <[email protected]>

teuthology/suite/merge.py

@@ -115,20 +115,22 @@ def config_merge(configs, suite_name=None, **kwargs):
     the entire job (config) from the list.
     """
     seed = kwargs.setdefault('seed', 1)
+    base_config = kwargs.setdefault('base_config', {})
     if not isinstance(seed, int):
         log.debug("no valid seed input: using 1")
         seed = 1
     log.debug("configuring Lua randomseed to %d", seed)
     L.execute(f'local math = require"math"; math.randomseed({seed});')
     new_script = L.eval('new_script')
+    base_config_yaml = yaml.safe_load(str(base_config))
     yaml_cache = {}
     for desc, paths in configs:
         log.debug("merging config %s", desc)
 
         if suite_name is not None:
             desc = combine_path(suite_name, desc)
 
-        yaml_complete_obj = {}
+        yaml_complete_obj = copy.deepcopy(base_config_yaml)
         deep_merge(yaml_complete_obj, dict(TEUTHOLOGY_TEMPLATE))
         for path in paths:
             if path not in yaml_cache:

teuthology/suite/run.py

@@ -643,14 +643,6 @@ def schedule_suite(self):
             seed=self.args.seed,
             suite_name=suite_name))
 
-        # create, but do not write, the temp file here, so it can be
-        # added to the args in collect_jobs, but not filled until
-        # any backtracking is done
-        base_yaml_path = NamedTemporaryFile(
-            prefix='schedule_suite_', delete=False
-        ).name
-        self.base_yaml_paths.insert(0, base_yaml_path)
-
         # compute job limit in respect of --sleep-before-teardown
         job_limit = self.args.limit or 0
         sleep_before_teardown = int(self.args.sleep_before_teardown or 0)
@@ -715,9 +707,6 @@ def schedule_suite(self):
                     dry_run=self.args.dry_run,
                 )
 
-        with open(base_yaml_path, 'w+b') as base_yaml:
-            base_yaml.write(str(self.base_config).encode())
-
         if jobs_to_schedule:
             self.write_rerun_memo()
 
@@ -729,8 +718,6 @@ def schedule_suite(self):
 
         self.schedule_jobs(jobs_missing_packages, jobs_to_schedule, name)
 
-        os.remove(base_yaml_path)
-
         count = len(jobs_to_schedule)
         missing_count = len(jobs_missing_packages)
         total_count = count