Reponse: Fix incomplete implementation in write

Write function in http_response.hpp missing implementation for first
write after changing from filebody.
Usecase:
Current resonse type is filebody. Developer tries to change the body
type to stringbody by calling write function.
Observed:
The write fails to update the body type.
Expected:
Write should succeed and body should change to string body.

Tested:
Unit test has been added for crow::Response.
Manual sanity test done for file offloads using curl.

Change-Id: Icbf8585b5b04c3ac5120d7b334c13d89ed3eb4aa
Signed-off-by: Abhilash Raju <abhilash.kollam@gmail.com>

1 files changed, 91 insertions, 0 deletions

diff --git a/test/http/http_response_test.cpp b/test/http/http_response_test.cpp
new file mode 100644
index 0000000000..c644ea9c05
--- /dev/null
+++ b/test/http/http_response_test.cpp
@@ -0,0 +1,91 @@
+#include "boost/beast/core/flat_buffer.hpp"
+#include "boost/beast/http/serializer.hpp"
+#include "http/http_response.hpp"
+
+#include <filesystem>
+#include <fstream>
+#include <thread>
+
+#include "gtest/gtest.h"
+namespace
+{
+void addHeaders(crow::Response& res)
+{
+    res.addHeader("myheader", "myvalue");
+    res.keepAlive(true);
+    res.result(boost::beast::http::status::ok);
+}
+void verifyHeaders(crow::Response& res)
+{
+    EXPECT_EQ(res.getHeaderValue("myheader"), "myvalue");
+    EXPECT_EQ(res.keepAlive(), true);
+    EXPECT_EQ(res.result(), boost::beast::http::status::ok);
+}
+
+std::string makeFile()
+{
+    std::filesystem::path path = std::filesystem::temp_directory_path();
+    path /= "bmcweb_http_response_test_XXXXXXXXXXX";
+    std::string stringPath = path.string();
+    int fd = mkstemp(stringPath.data());
+    EXPECT_GT(fd, 0);
+    std::string_view sample = "sample text";
+    EXPECT_EQ(write(fd, sample.data(), sample.size()), sample.size());
+    return stringPath;
+}
+TEST(HttpResponse, Defaults)
+{
+    crow::Response res;
+    EXPECT_EQ(
+        boost::variant2::holds_alternative<crow::Response::string_response>(
+            res.response),
+        true);
+}
+TEST(HttpResponse, Headers)
+{
+    crow::Response res;
+    addHeaders(res);
+    verifyHeaders(res);
+}
+TEST(HttpResponse, StringBody)
+{
+    crow::Response res;
+    addHeaders(res);
+    std::string_view bodyvalue = "this is my new body";
+    res.write({bodyvalue.data(), bodyvalue.length()});
+    EXPECT_EQ(*res.body(), bodyvalue);
+    verifyHeaders(res);
+}
+TEST(HttpResponse, FileBody)
+{
+    crow::Response res;
+    addHeaders(res);
+    std::string path = makeFile();
+    res.openFile(path);
+
+    verifyHeaders(res);
+    std::filesystem::remove(path);
+}
+TEST(HttpResponse, BodyTransitions)
+{
+    crow::Response res;
+    addHeaders(res);
+    std::string path = makeFile();
+    res.openFile(path);
+
+    EXPECT_EQ(boost::variant2::holds_alternative<crow::Response::file_response>(
+                  res.response),
+              true);
+
+    verifyHeaders(res);
+    res.write("body text");
+
+    EXPECT_EQ(
+        boost::variant2::holds_alternative<crow::Response::string_response>(
+            res.response),
+        true);
+
+    verifyHeaders(res);
+    std::filesystem::remove(path);
+}
+} // namespace