regulators: Implements support for if action

Enhance the configuration file parser to support the if action element.

Signed-off-by: Bob King <Bob_King@wistron.com>
Change-Id: Iadb6835dd28151a1dd278f6b2a19568a3072ad5e
diff --git a/phosphor-regulators/src/config_file_parser.cpp b/phosphor-regulators/src/config_file_parser.cpp
index 8c6dc12..9615d31 100644
--- a/phosphor-regulators/src/config_file_parser.cpp
+++ b/phosphor-regulators/src/config_file_parser.cpp
@@ -114,9 +114,8 @@
     }
     else if (element.contains("if"))
     {
-        // TODO: Not implemented yet
-        // action = parseIf(element["if"]);
-        // ++propertyCount;
+        action = parseIf(element["if"]);
+        ++propertyCount;
     }
     else if (element.contains("not"))
     {
@@ -574,6 +573,39 @@
     return std::make_unique<I2CWriteBytesAction>(reg, values, masks);
 }
 
+std::unique_ptr<IfAction> parseIf(const json& element)
+{
+    verifyIsObject(element);
+    unsigned int propertyCount{0};
+
+    // Required condition property
+    const json& conditionElement = getRequiredProperty(element, "condition");
+    std::unique_ptr<Action> conditionAction = parseAction(conditionElement);
+    ++propertyCount;
+
+    // Required then property
+    const json& thenElement = getRequiredProperty(element, "then");
+    std::vector<std::unique_ptr<Action>> thenActions =
+        parseActionArray(thenElement);
+    ++propertyCount;
+
+    // Optional else property
+    std::vector<std::unique_ptr<Action>> elseActions{};
+    auto elseIt = element.find("else");
+    if (elseIt != element.end())
+    {
+        elseActions = parseActionArray(*elseIt);
+        ++propertyCount;
+    }
+
+    // Verify no invalid properties exist
+    verifyPropertyCount(element, propertyCount);
+
+    return std::make_unique<IfAction>(std::move(conditionAction),
+                                      std::move(thenActions),
+                                      std::move(elseActions));
+}
+
 std::unique_ptr<NotAction> parseNot(const json& element)
 {
     // Required action to execute
diff --git a/phosphor-regulators/src/config_file_parser.hpp b/phosphor-regulators/src/config_file_parser.hpp
index 7104356..e04f81f 100644
--- a/phosphor-regulators/src/config_file_parser.hpp
+++ b/phosphor-regulators/src/config_file_parser.hpp
@@ -27,6 +27,7 @@
 #include "i2c_write_bit_action.hpp"
 #include "i2c_write_byte_action.hpp"
 #include "i2c_write_bytes_action.hpp"
+#include "if_action.hpp"
 #include "not_action.hpp"
 #include "or_action.hpp"
 #include "pmbus_write_vout_command_action.hpp"
@@ -417,6 +418,18 @@
     parseI2CWriteBytes(const nlohmann::json& element);
 
 /**
+ * Parses a JSON element containing an if action.
+ *
+ * Returns the corresponding C++ IfAction object.
+ *
+ * Throws an exception if parsing fails.
+ *
+ * @param element JSON element
+ * @return IfAction object
+ */
+std::unique_ptr<IfAction> parseIf(const nlohmann::json& element);
+
+/**
  * Parses a JSON element containing an 8-bit signed integer.
  *
  * Returns the corresponding C++ int8_t value.
diff --git a/phosphor-regulators/test/config_file_parser_tests.cpp b/phosphor-regulators/test/config_file_parser_tests.cpp
index 4c53c6c..5223e54 100644
--- a/phosphor-regulators/test/config_file_parser_tests.cpp
+++ b/phosphor-regulators/test/config_file_parser_tests.cpp
@@ -349,7 +349,20 @@
     }
 
     // Test where works: if action type specified
-    // TODO: Not implemented yet
+    {
+        const json element = R"(
+            {
+              "if":
+              {
+                "condition": { "run_rule": "is_downlevel_regulator" },
+                "then": [ { "run_rule": "configure_downlevel_regulator" } ],
+                "else": [ { "run_rule": "configure_standard_regulator" } ]
+              }
+            }
+        )"_json;
+        std::unique_ptr<Action> action = parseAction(element);
+        EXPECT_NE(action.get(), nullptr);
+    }
 
     // Test where works: not action type specified
     {
@@ -2516,6 +2529,157 @@
     }
 }
 
+TEST(ConfigFileParserTests, ParseIf)
+{
+    // Test where works: Only required properties specified
+    {
+        const json element = R"(
+            {
+              "condition": { "run_rule": "is_downlevel_regulator" },
+              "then": [ { "run_rule": "configure_downlevel_regulator" },
+                        { "run_rule": "configure_standard_regulator" } ]
+            }
+        )"_json;
+        std::unique_ptr<IfAction> action = parseIf(element);
+        EXPECT_NE(action->getConditionAction().get(), nullptr);
+        EXPECT_EQ(action->getThenActions().size(), 2);
+        EXPECT_EQ(action->getElseActions().size(), 0);
+    }
+
+    // Test where works: All properties specified
+    {
+        const json element = R"(
+            {
+              "condition": { "run_rule": "is_downlevel_regulator" },
+              "then": [ { "run_rule": "configure_downlevel_regulator" } ],
+              "else": [ { "run_rule": "configure_standard_regulator" } ]
+            }
+        )"_json;
+        std::unique_ptr<IfAction> action = parseIf(element);
+        EXPECT_NE(action->getConditionAction().get(), nullptr);
+        EXPECT_EQ(action->getThenActions().size(), 1);
+        EXPECT_EQ(action->getElseActions().size(), 1);
+    }
+
+    // Test where fails: Required condition property not specified
+    try
+    {
+        const json element = R"(
+            {
+              "then": [ { "run_rule": "configure_downlevel_regulator" } ],
+              "else": [ { "run_rule": "configure_standard_regulator" } ]
+            }
+        )"_json;
+        parseIf(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Required property missing: condition");
+    }
+
+    // Test where fails: Required then property not specified
+    try
+    {
+        const json element = R"(
+            {
+              "condition": { "run_rule": "is_downlevel_regulator" },
+              "else": [ { "run_rule": "configure_standard_regulator" } ]
+            }
+        )"_json;
+        parseIf(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Required property missing: then");
+    }
+
+    // Test where fails: condition value is invalid
+    try
+    {
+        const json element = R"(
+            {
+              "condition": 1,
+              "then": [ { "run_rule": "configure_downlevel_regulator" } ],
+              "else": [ { "run_rule": "configure_standard_regulator" } ]
+            }
+        )"_json;
+        parseIf(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Element is not an object");
+    }
+
+    // Test where fails: then value is invalid
+    try
+    {
+        const json element = R"(
+            {
+              "condition": { "run_rule": "is_downlevel_regulator" },
+              "then": "foo",
+              "else": [ { "run_rule": "configure_standard_regulator" } ]
+            }
+        )"_json;
+        parseIf(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Element is not an array");
+    }
+
+    // Test where fails: else value is invalid
+    try
+    {
+        const json element = R"(
+            {
+              "condition": { "run_rule": "is_downlevel_regulator" },
+              "then": [ { "run_rule": "configure_downlevel_regulator" } ],
+              "else": 1
+            }
+        )"_json;
+        parseIf(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Element is not an array");
+    }
+
+    // Test where fails: Invalid property specified
+    try
+    {
+        const json element = R"(
+            {
+              "condition": { "run_rule": "is_downlevel_regulator" },
+              "then": [ { "run_rule": "configure_downlevel_regulator" } ],
+              "foo": "bar"
+            }
+        )"_json;
+        parseIf(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Element contains an invalid property");
+    }
+
+    // Test where fails: Element is not an object
+    try
+    {
+        const json element = R"( [ "0xFF", "0x01" ] )"_json;
+        parseIf(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Element is not an object");
+    }
+}
+
 TEST(ConfigFileParserTests, ParseInt8)
 {
     // Test where works: INT8_MIN