SERVER-73740: Allow old FCV constants to be parsed by min_fcv

ImTheKai · Mar 20, 2023 · 52bda34 · 52bda34
1 parent 073ab04
commit 52bda34
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Showing 3 changed files with 6 additions and 2 deletions.
diff --git a/buildscripts/idl/idl/generator.py b/buildscripts/idl/idl/generator.py
@@ -2705,7 +2705,7 @@ def gen_server_parameters(self, params, header_file_name):
                                                     (param_no, param.condition.feature_flag))
                         if param.condition.min_fcv:
                             self._writer.write_line(
-                                'scp_%d->setMinFCV(FeatureCompatibilityVersionParser::parseVersion("%s"));'
+                                'scp_%d->setMinFCV(FeatureCompatibilityVersionParser::parseVersionForFeatureFlags("%s"));'
                                 % (param_no, param.condition.min_fcv))
 
                     self._gen_server_parameter_deprecated_aliases(param_no, param)

diff --git a/docs/server-parameters.md b/docs/server-parameters.md
@@ -129,6 +129,10 @@ no provided setting evaluates to `false`, the server parameter will be registere
 is enabled. `min_fcv` is a string of the form `X.Y`, representing the minimum FCV version for which
 this parameter should be enabled. `feature_flag` is the name of a feature flag variable upon which
 this server parameter depends -- if the feature flag is disabled, this parameter will be disabled.
+`feature_flag` should be removed when all other instances of that feature flag are deleted, which
+typically is done after the next LTS version of the server is branched. `min_fcv` should be removed
+after it is no longer possible to downgrade to a FCV lower than that version - this occurs when the
+next LTS version of the server is branched.
 
 * `validator`: Zero or many validation rules to impose on the setting. All specified rules must pass 
 to consider the new setting valid. `lt`, `gt`, `lte`, `gte` fields provide for simple numeric limits 

diff --git a/src/mongo/db/change_streams_cluster_parameter.idl b/src/mongo/db/change_streams_cluster_parameter.idl
@@ -59,7 +59,7 @@ server_parameters:
     validator:
       callback: validateChangeStreamsClusterParameter
     condition:
-      min_fcv: 6.3
+      min_fcv: 6.2
   changeCollectionExpiredDocumentsRemoverJobSleepSeconds:
     description: "Specifies the number of seconds for which the periodic change collection remover job will sleep between each cycle."
     set_at: [ startup ]