add hex helpers for LSSE

app/models/log_store_sst_entry.rb

@@ -1,12 +1,24 @@
 class LogStoreSstEntry < ReduxApplicationRecord
-  def key_hex
-    self.hex2bin(self.key)
+  # columns:
+  # key - bytea
+  # value - bytea
+
+  def hex_key
+    self.class.bin2hex(self.key)
+  end
+
+  def hex_value
+    self.class.bin2hex(self.value)
+  end
+
+  def self.find_by_hex_key(key_hex)
+    self.find_by(key: self.hex2bin(key_hex))
   end
 
   def self.hex2bin(str)
     [str].pack("H*")
   end
   def self.bin2hex(bin)
-    bin.unpack("H*").first
+    bin.unpack("H*").first.upcase
   end
 end