Fixes #10079: Add a generic method to merge two dict variables

tests/acceptance/30_generic_methods/variable_dict_merge.cf

@@ -0,0 +1,66 @@
+#######################################################
+#
+# Create a dict variable by merging two other variables
+#
+#######################################################
+
+bundle common acc_path
+{
+  vars:
+    "root" string => getenv("NCF_TESTS_ACCEPTANCE", 1024);
+}
+
+body common control
+{
+      inputs => { "${acc_path.root}/default.cf.sub", "${acc_path.root}/default_ncf.cf.sub", "@{ncf_inputs.default_files}" };
+      bundlesequence  => { configuration, default("${this.promise_filename}") };
+      version => "1.0";
+}
+
+#######################################################
+
+bundle agent init
+{
+  vars:
+
+    "dict1" data => parsejson('{ "key1": "value1", "key2": "value2", "key3": { "keyx": "valuex" }, "key4": [ "valuey" ] }');
+    "dict2" data => parsejson('{ "key1": "value1bis", "key4": "value4" }');
+    "ref" string => '{
+  "key1": "value1bis",
+  "key2": "value2",
+  "key3": {
+    "keyx": "valuex"
+  },
+  "key4": "value4"
+}';
+
+}
+
+#######################################################
+
+bundle agent test
+{
+  methods:
+    "ph3" usebundle => variable_dict_merge("prefix", "var3", "init.dict1", "init.dict2");
+}
+
+#######################################################
+
+bundle agent check
+{
+  vars:
+    "result" string => storejson("prefix.var3");
+
+  classes:
+
+    "ok_class" expression => "variable_dict_merge_var3_kept.!variable_dict_merge_var3_repaired.!variable_dict_merge_var3_error";
+    "ok_value" expression => strcmp("${result}", "${init.ref}");
+
+    "ok"  expression => "ok_class.ok_value";
+
+  reports:
+    ok::
+      "$(this.promise_filename) Pass";
+    !ok::
+      "$(this.promise_filename) FAIL";
+}

tree/30_generic_methods/variable_dict_merge.cf

@@ -0,0 +1,97 @@
+#####################################################################################
+# Copyright 2017 Normation SAS
+#####################################################################################
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, Version 3.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+#####################################################################################
+
+# @name Variable dict merge
+# @description Define a variable resulting of the merge of two other variables
+# @documentation To use the generated variable, you must use the form `${variable_prefix.variable_name[key]}` with each name replaced with the parameters of this method.
+#
+# The resulting variable will be the merge of the two parameters, which means it is built by:
+#
+# * Taking the content of the first variable
+# * Adding the content of the second variable, and replace the kays that were already there
+#
+# It is only a one-level merge, and the value of the first-lvel key will be completely replaced by the merge.
+#
+#### Usage
+#
+# If you have a `prefix.variable1` variable defined by:
+#
+# ```json
+# { "key1": "value1", "key2": "value2", "key3": { "keyx": "valuex" } }
+# ```
+#
+# And a `prefix.variable2` variable defined by:
+#
+# ```json
+# { "key1": "different", "key3": "value3", "key4": "value4" }
+# ```
+#
+# And that you use:
+#
+# ```
+# variablr_dict_merge("prefix", "variable3, "prefix.variable1", "prefix.variable2")
+# ```
+#
+# You will get a `prefix.variable3` variable containing:
+#
+# ```json
+# {
+#   "key1": "different",
+#   "key2": "value2",
+#   "key3": "value3",
+#   "key4": "value4"
+# }
+# ```
+#
+# @parameter variable_prefix The prefix of the variable name
+# @parameter variable_name   The variable to define, the full name will be variable_prefix.variable_name
+# @parameter first_variable  The first variable, which content will be overriden in the resulting variable if necessary (written in the form variable_prefix.variable_name)
+# @parameter second_variable The second variable, which content will override the first in the resulting variable if necessary (written in the form variable_prefix.variable_name)
+#
+# @agent_version >=3.6
+# 
+# @class_prefix variable_dict_merge
+# @class_parameter variable_name
+
+bundle agent variable_dict_merge(variable_prefix, variable_name, first_variable, second_variable)
+{
+  vars:
+      "old_class_prefix"  string => canonify("variable_dict_merge_${variable_name}");
+      "promisers"          slist => { @{this.callers_promisers}, cf_null }, policy => "ifdefined";
+      "class_prefix"      string => canonify(join("_", "promisers"));
+      "args"               slist => { "${variable_prefix}", "${variable_name}", "${first_variable}", "${second_variable}" };
+
+      # define the variable within the variable_prefix namespace
+      "${variable_prefix}.${variable_name}"  data => mergedata("${first_variable}", "${second_variable}");
+
+  classes:
+     "variable_defined" expression => isvariable("${variable_prefix}.${variable_name}");
+
+  methods:
+    !variable_defined::
+      "error"    usebundle => _classes_failure("${old_class_prefix}");
+      "error"    usebundle => _classes_failure("${class_prefix}");
+
+    variable_defined::
+      "success"  usebundle => _classes_success("${old_class_prefix}");
+      "success"  usebundle => _classes_success("${class_prefix}");
+
+    any::
+      "report"
+        usebundle  => _log("Set the dict ${variable_prefix}.${variable_name} to the content of the merge of ${first_variable} and ${second_variable}", "${old_class_prefix}", "${class_prefix}", @{args});
+}