feat: Implement C-binding for Value type. (#33)

Co-authored-by: Casey Waldren <[email protected]>

Author: kinyoklion

CMakeLists.txt

@@ -24,7 +24,17 @@ set(CMAKE_CXX_STANDARD 17)
 
 option(BUILD_TESTING "Enable C++ unit tests." ON)
 
+# If you want to run the unit tests with valgrind, then TESTING_SANITIZERS must of OFF.
+option(TESTING_SANITIZERS "Enable sanitizers for unit tests." ON)
+
 if (BUILD_TESTING)
+    if (TESTING_SANITIZERS)
+        if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+            set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fsanitize=address -fsanitize=undefined -fsanitize=leak")
+        elseif (CMAKE_CXX_COMPILER_ID STREQUAL " GNU")
+            set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fsanitize=address -fsanitize=leak")
+        endif ()
+    endif ()
     include(FetchContent)
     FetchContent_Declare(
             googletest

libs/common/CMakeLists.txt

@@ -21,7 +21,7 @@ if (CMAKE_PROJECT_NAME STREQUAL PROJECT_NAME)
     set_property(GLOBAL PROPERTY USE_FOLDERS ON)
 endif ()
 
-# Needed to fetch external dependencies. 
+# Needed to fetch external dependencies.
 include(FetchContent)
 
 set(OPENSSL_USE_STATIC_LIBS OFF)

libs/common/include/attributes_builder.hpp

@@ -126,15 +126,7 @@ class AttributesBuilder final {
      * In this example, firstName is marked as private, but lastName is not:
      *
      * ```
-     * const context = {
-     *   kind: 'org',
-     *   key: 'my-key',
-     *   firstName: 'Pierre',
-     *   lastName: 'Menard',
-     *   _meta: {
-     *     privateAttributes: ['firstName'],
-     *   }
-     * };
+     * [TODO]
      * ```
      *
      * This is a metadata property, rather than an attribute that can be

libs/common/include/c_bindings/array_builder.h

@@ -0,0 +1,57 @@
+// NOLINTBEGIN modernize-use-using
+
+#pragma once
+
+#include "./export.h"
+#include "./value.h"
+
+#ifdef __cplusplus
+extern "C" {  // only need to export C interface if
+// used by C++ source code
+#endif
+
+typedef struct _LDArrayBuilder* LDArrayBuilder;
+
+/**
+ * Construct a new array builder.
+ * @return The new array builder.
+ *
+ */
+LD_EXPORT(LDArrayBuilder) LDArrayBuilder_New();
+
+/**
+ * Free an array builder. This should only be done for a builder which
+ * has not been built. Calling LDArrayBuilder_Build on an array builder
+ * transfers consumes the array builder.
+ *
+ * @param array_builder The builder to free.
+ */
+LD_EXPORT(void) LDArrayBuilder_Free(LDArrayBuilder array_builder);
+
+/**
+ * Add a value to an array builder.
+ *
+ * After calling this method the provider LDValue is consumed. It should not
+ * be accessed, and the caller doesn't need to call LDValue_Free.
+ *
+ * @param array_builder The array builder to add the value to.
+ * @param val The value to add.
+ */
+LD_EXPORT(void) LDArrayBuilder_Add(LDArrayBuilder array_builder, LDValue val);
+
+/**
+ * Construct an LDValue from an array builder.
+ *
+ * After calling this method the array builder is consumed. It should not be
+ * used and the caller does not need to call LDArrayBuilder_Free.
+ *
+ * @param array_builder The array builder to build an LDValue from.
+ * @return The built LDValue.
+ */
+LD_EXPORT(LDValue) LDArrayBuilder_Build(LDArrayBuilder array_builder);
+
+#ifdef __cplusplus
+}
+#endif
+
+// NOLINTEND modernize-use-using

libs/common/include/c_bindings/context.h

@@ -0,0 +1,119 @@
+// NOLINTBEGIN modernize-use-using
+
+#pragma once
+
+#include "./export.h"
+#include "./value.h"
+
+#include <stdbool.h>
+
+#ifdef __cplusplus
+extern "C" {  // only need to export C interface if
+// used by C++ source code
+#endif
+
+typedef struct _LDContext* LDContext;
+typedef struct _LDContext_PrivateAttributesIter*
+    LDContext_PrivateAttributesIter;
+
+/**
+ * Check if the context is valid.
+ *
+ * @param context The context to check.
+ * @return True if the context is valid.
+ */
+LD_EXPORT(bool) LDContext_Valid(LDContext context);
+
+/**
+ * Free the context.
+ *
+ * @param context The context to free.
+ */
+LD_EXPORT(void) LDContext_Free(LDContext context);
+
+/**
+ * Get an attribute value by kind and attribute reference. If the kind is
+ * not present, or the attribute not present in the kind, then
+ * a null pointer will be returned.
+ *
+ * The lifetime of the LDValue is tied to the LDContext it was accessed from.
+ * Do not access a returned LDValue from a context after the context has been
+ * freed.
+ *
+ * @param context The context to get an attribute from
+ * @param kind The kind within the context to get the attribute from.
+ * @param ref An attribute reference representing the attribute to get.
+ * @return The attribute value or a null pointer.
+ */
+LD_EXPORT(LDValue)
+LDContext_Get(LDContext context, char const* kind, char const* ref);
+
+/**
+ * If the context is not valid, then get a string containing the reason the
+ * context is not valid.
+ *
+ * The lifetime of the returned string is tied to the LDContext.
+ *
+ * @param context The context to check for validity.
+ * @return A string explaining why the context is not valid.
+ */
+LD_EXPORT(char const*) LDContext_Errors(LDContext context);
+
+/**
+ * Create an iterator which iterates over the private attributes for the
+ * context kind. If there is no such context kind, then a null pointer will
+ * be returned.
+ *
+ * The iterator must be destroyed with LDContext_DestroyPrivateAttributesIter.
+ *
+ * An iterator must not be used after the associated Context has been
+ * freed.
+ *
+ * @param context The context containing the kind.
+ * @param kind The kind to iterate private attributes for.
+ * @return A private attributes iterator.
+ */
+LD_EXPORT(LDContext_PrivateAttributesIter)
+LDContext_CreatePrivateAttributesIter(LDContext context, char const* kind);
+
+/**
+ * Destroy the iterator.
+ *
+ * @param iter The iterator to destroy.
+ */
+LD_EXPORT(void)
+LDContext_DestroyPrivateAttributesIter(LDContext_PrivateAttributesIter iter);
+
+/**
+ * Move the iterator to the next item.
+ *
+ * @param iter The iterator to increment.
+ */
+LD_EXPORT(void)
+LDContext_PrivateAttributesIter_Next(LDContext_PrivateAttributesIter iter);
+
+/**
+ * Check if the iterator is at the end.
+ *
+ * @param iter The iterator to check.
+ * @return True if the iterator is at the end.
+ */
+LD_EXPORT(bool)
+LDContext_PrivateAttributesIter_End(LDContext_PrivateAttributesIter iter);
+
+/**
+ * Get the value pointed to by the iterator.
+ *
+ * The lifetime of the returned value is the same as the Context.
+ *
+ * @param iter The iterator to get a value for.
+ * @return The attribute reference as a string.
+ */
+LD_EXPORT(char const*)
+LDContext_PrivateAttributesIter_Value(LDContext_PrivateAttributesIter iter);
+
+#ifdef __cplusplus
+}
+#endif
+
+// NOLINTEND modernize-use-using