Fix[rmqa_compressiontransformerimpl]: check compression properties (#76)

Signed-off-by: Evgenii Malygin <emalygin@bloomberg.net>
Signed-off-by: Will <2185386+willhoy@users.noreply.github.com>
Co-authored-by: Will <2185386+willhoy@users.noreply.github.com>

Author: 678098

src/rmq/rmqa/rmqa_compressiontransformerimpl.cpp

@@ -125,17 +125,33 @@ rmqt::Result<> CompressionTransformerImpl::inverseTransform(
     bsl::shared_ptr<bsl::vector<uint8_t> >& data,
     rmqt::Properties& props)
 {
+
     BSLS_ASSERT(props.headers);
-    int64_t originalSize =
-        (*props.headers)["sdk.transform.compression.size"].the<int64_t>();
+
+    rmqt::FieldTable::const_iterator sizeIt =
+        props.headers->find("sdk.transform.compression.size");
+    if (sizeIt == props.headers->end() || !sizeIt->second.is<int64_t>()) {
+        BALL_LOG_ERROR << "Missing or invalid compression size header";
+        return rmqt::Result<>("Missing or invalid compression size header");
+    }
+
+    int64_t originalSize = sizeIt->second.the<int64_t>();
+
     if (originalSize <= 0) {
         BALL_LOG_ERROR << "Invalid original size for decompression: "
                        << originalSize;
         return rmqt::Result<>("Invalid original size for decompression: " +
                               bsl::to_string(originalSize));
     }
-    bsl::string compressionAlg =
-        (*props.headers)["sdk.transform.compression.alg"].the<bsl::string>();
+
+    rmqt::FieldTable::const_iterator algIt =
+        props.headers->find("sdk.transform.compression.alg");
+    if (algIt == props.headers->end() || !algIt->second.is<bsl::string>()) {
+        BALL_LOG_ERROR << "Missing or invalid compression algorithm header";
+        return rmqt::Result<>(
+            "Missing or invalid compression algorithm header");
+    }
+    bsl::string compressionAlg = algIt->second.the<bsl::string>();
 
     rmqt::Result<> result;
     if (compressionAlg == "zstd") {