Made protocol_version configurable via Augments

This change implements easy configuration of protocol_version in body common control for the standard MPF entries.

Ticket: CFE-4543
Changelog: Title

Author: nickanderson

MPF.md

@@ -1306,6 +1306,38 @@ Example definition in augments file:
 }
 ```
 
+### Specify the CFEngine protocol version to use
+
+By default CFEngine will negotiate the newest protocol version available. Configuring `protocol_version` will restrict the protocol to the specified version.
+
+```json
+{
+  "variables": {
+    "default:def.control_common_protocol_version": {
+      "value": "filestream"
+      }
+  }
+}
+```
+
+**Notes:**
+
+- Valid values for `protocol_version` can be extracted from the syntax-description output of `cf-promises`.
+
+  For example:
+
+  ```command
+  cf-promises --syntax-description=json | jq -r '.bodyTypes.common.attributes.protocol_version.range'`
+  ```
+
+  ```output
+  (1|classic|2|tls|3|cookie|4|filestream|latest)
+  ```
+
+**History:**
+
+- Added in CFEngine 3.27.0
+
 ### Configure the ciphers used by cf-serverd
 
 When `default:def.control_server_allowciphers` is defined `cf-serverd` will use the ciphers specified instead of the binary defaults.

controls/def.cf

@@ -399,6 +399,14 @@ bundle common def
         comment => concat( "The minimum log level required for log messages to go to the",
                            " system log (e.g. syslog or Windows Event Log).",
                            " (critical|error|warning|notice|info)" );
+
+      "control_common_protocol_version_defined" -> { "CFE-4543" }
+        expression => isvariable( "default:def.control_common_protocol_version" ),
+        comment => concat( "Defines the protocol version to use for all outgoing",
+                           " connections.",
+                           # It's challenging to keep this aligned with the core agent code
+                           # cf-promises --syntax-description=json | jq -r '.bodyTypes.common.attributes.protocol_version.range'
+                           " (1|classic|2|tls|3|cookie|4|filestream|latest)" );
   vars:
 
     debian::

controls/update_def.cf.in

@@ -11,6 +11,14 @@ bundle common update_def
                            " system log (e.g. syslog or Windows Event Log).",
                            " (critical|error|warning|notice|info)" );
 
+      "control_common_protocol_version_defined" -> { "CFE-4543" }
+        expression => isvariable( "default:def.control_common_protocol_version" ),
+        comment => concat( "Defines the protocol version to use for all outgoing",
+                           " connections.",
+                           # It's challenging to keep this aligned with the core agent code
+                           # cf-promises --syntax-description=json | jq -r '.bodyTypes.common.attributes.protocol_version.range'
+                           " (1|classic|2|tls|3|cookie|4|filestream|latest)" );
+
   vars:
       "hub_binary_version" -> { "ENT-10664" }
         data => data_regextract(

promises.cf.in

@@ -141,6 +141,9 @@ body common control
 
     control_common_system_log_level_defined::
         system_log_level => "$(default:def.control_common_system_log_level)";
+
+    control_common_protocol_version_defined::
+      protocol_version => "$(default:def.control_common_protocol_version)";
 }
 
 bundle common inventory

standalone_self_upgrade.cf.in

@@ -49,6 +49,13 @@ bundle common def_standalone_self_upgrade
                            " system log (e.g. syslog or Windows Event Log).",
                            " (critical|error|warning|notice|info)" );
 
+      "control_common_protocol_version_defined" -> { "CFE-4543" }
+        expression => isvariable( "default:def.control_common_protocol_version" ),
+        comment => concat( "Defines the protocol version to use for all outgoing",
+                           " connections.",
+                           # It's challenging to keep this aligned with the core agent code
+                           # cf-promises --syntax-description=json | jq -r '.bodyTypes.common.attributes.protocol_version.range'
+                           " (1|classic|2|tls|3|cookie|4|filestream|latest)" );
 }
 body agent control
 # @brief Agent controls for standalone self upgrade
@@ -884,6 +891,9 @@ body common control
 
     control_common_system_log_level_defined::
         system_log_level => "$(default:def.control_common_system_log_level)";
+
+    control_common_protocol_version_defined::
+        protocol_version => "$(default:def.control_common_protocol_version)";
 }
 
 body depth_search u_recurse_basedir(d)

update.cf.in

@@ -43,6 +43,9 @@ body common control
 
     control_common_system_log_level_defined::
         system_log_level => "$(default:def.control_common_system_log_level)";
+
+    control_common_protocol_version_defined::
+        protocol_version => "$(default:def.control_common_protocol_version)";
 }
 
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