intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 86 insertions, 0 deletions

diff --git a/library/cpp/monlib/service/format.h b/library/cpp/monlib/service/format.h
new file mode 100644
index 0000000000..0044b586b1
--- /dev/null
+++ b/library/cpp/monlib/service/format.h
@@ -0,0 +1,86 @@
+#pragma once
+
+#include <library/cpp/monlib/encode/format.h>
+
+#include <util/string/ascii.h>
+#include <util/generic/yexception.h>
+#include <util/generic/typetraits.h>
+
+namespace NMonitoring {
+    namespace NPrivate {
+        Y_HAS_MEMBER(Name, Name);
+        Y_HAS_MEMBER(second, Second);
+    } // namespace NPrivate
+
+    template <typename TRequest>
+    ECompression ParseCompression(const TRequest& req) {
+        auto&& headers = req.GetHeaders();
+
+        constexpr auto isPlainPair = NPrivate::THasSecond<std::decay_t<decltype(*headers.begin())>>::value;
+
+        auto it = FindIf(std::begin(headers), std::end(headers),
+            [=] (const auto& h) {
+                if constexpr (NPrivate::THasName<std::decay_t<decltype(h)>>::value) {
+                    return AsciiCompareIgnoreCase(h.Name(), TStringBuf("accept-encoding")) == 0;
+                } else if (isPlainPair) {
+                    return AsciiCompareIgnoreCase(h.first, TStringBuf("accept-encoding")) == 0;
+                }
+            });
+
+        if (it == std::end(headers)) {
+            return NMonitoring::ECompression::IDENTITY;
+        }
+
+        NMonitoring::ECompression val{};
+        if constexpr (isPlainPair) {
+            val = CompressionFromAcceptEncodingHeader(it->second);
+        } else {
+            val = CompressionFromAcceptEncodingHeader(it->Value());
+        }
+
+        return val != NMonitoring::ECompression::UNKNOWN
+            ? val
+            : NMonitoring::ECompression::IDENTITY;
+    }
+
+    template <typename TRequest>
+    NMonitoring::EFormat ParseFormat(const TRequest& req) {
+        auto&& formatStr = req.GetParams()
+            .Get(TStringBuf("format"));
+
+        if (!formatStr.empty()) {
+            if (formatStr == TStringBuf("SPACK")) {
+                return EFormat::SPACK;
+            } else if (formatStr == TStringBuf("TEXT")) {
+                return EFormat::TEXT;
+            } else if (formatStr == TStringBuf("JSON")) {
+                return EFormat::JSON;
+            } else {
+                ythrow yexception() << "unknown format: " << formatStr << ". Only spack is supported here";
+            }
+        }
+
+        auto&& headers = req.GetHeaders();
+        constexpr auto isPlainPair = NPrivate::THasSecond<std::decay_t<decltype(*headers.begin())>>::value;
+
+        auto it = FindIf(std::begin(headers), std::end(headers),
+            [=] (const auto& h) {
+                if constexpr (NPrivate::THasName<std::decay_t<decltype(h)>>::value) {
+                    return AsciiCompareIgnoreCase(h.Name(), TStringBuf("accept")) == 0;
+                } else if (isPlainPair) {
+                    return AsciiCompareIgnoreCase(h.first, TStringBuf("accept")) == 0;
+                }
+            });
+
+        if (it != std::end(headers)) {
+            if constexpr (isPlainPair) {
+                return FormatFromAcceptHeader(it->second);
+            } else {
+                return FormatFromAcceptHeader(it->Value());
+            }
+        }
+
+        return EFormat::UNKNOWN;
+    }
+
+} // namespace NMonitoring