fix: improve avro library detection

So far we checked for the presence of the library in the target schema
class file but this library could be loaded indirectly and not
explicitely listed.

As a fallback, we now:

 - look for the library string without the import keyword, to allow
   to specify it using the schemas static annotation if needed
   (for instance '@Schema(library="com.sksamuel.avro4s")')

 - search for the library in the build.sbt as well.

Author: Yann Rouillard

kafka/check-local-schemas.sh

@@ -61,12 +61,27 @@ find_schema_class() {
   echo "${schema_package}.${schema_class_name}"
 }
 
+is_library_used() {
+  local library="$1" candidate_class_file="$2"
+
+  # if the library is not directly found in the candidate class file
+  # we fallback on checking the build.sbt file itself
+  # This doesn't fully protect against from indirect library loading
+  # but it's a good enough heuristic for now
+  for candidate in "${candidate_class_file}" build.sbt; do
+    if grep -q -E "[^#]*${library}" "${candidate}"; then
+      return 0
+    fi
+  done
+  return 1
+}
+
 find_avro_library() {
   local schema_class_file="$1"
 
-  if grep -q "import com.sksamuel.avro4s" "${schema_class_file}"; then
+  if is_library_used "com.sksamuel.avro4s" "${schema_class_file}"; then
     echo "avro4s"
-  elif grep -q "import vulcan" "${schema_class_file}"; then
+  elif is_library_used "vulcan" "${schema_class_file}"; then
     echo "vulcan"
   else
     error "Could not find any avro library import in ${schema_class_file}"