feat: Add dynamic file type support for catalog uploads (CSV, JSON, JSONL) additional changes (#178)

* feat: add support for multiple file types in catalog uploads

* validates .csv, .json and .jsonl
* derive the file extension from the uploaded file.

* chore: added relevant tests

* Update tests

* Utilize set

* Use LinkedHashSet

* Use generators instead of static files

* Lint and cleanup

* Utilize existing functions

* Cleanup

* Lint

* Address comments

---------

Co-authored-by: Mazin <ahmedmaazin@gmail.com>

Author: esezen

constructorio-client/src/main/java/io/constructor/client/ConstructorIO.java

@@ -10,8 +10,10 @@
 import java.util.Arrays;
 import java.util.Base64;
 import java.util.HashMap;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import java.util.concurrent.TimeUnit;
 import okhttp3.Call;
 import okhttp3.Callback;
@@ -33,6 +35,10 @@
 /** Constructor.io Client */
 public class ConstructorIO {
 
+    /** Valid file extensions for catalog uploads */
+    private static final Set<String> VALID_CATALOG_EXTENSIONS =
+            new LinkedHashSet<>(Arrays.asList(".csv", ".json", ".jsonl"));
+
     /** the HTTP client used by all instances */
     private static OkHttpClient client =
             new OkHttpClient.Builder()
@@ -2041,6 +2047,53 @@ protected static String getResponseBody(Response response) throws ConstructorExc
         throw new ConstructorException(errorMessage, errorCode);
     }
 
+    /**
+     * Validates and extracts the file extension from a File object for catalog uploads.
+     *
+     * @param file the File object containing the actual file
+     * @param fileName the logical file name (items, variations, item_groups)
+     * @return the validated file extension (including the dot, e.g., ".csv", ".json", or ".jsonl")
+     * @throws ConstructorException if the file extension is not in VALID_CATALOG_EXTENSIONS
+     */
+    private static String getValidatedFileExtension(File file, String fileName)
+            throws ConstructorException {
+        if (file == null) {
+            throw new ConstructorException(
+                    "Invalid file for '" + fileName + "': file cannot be null.");
+        }
+
+        String actualFileName = file.getName();
+        if (actualFileName == null || actualFileName.isEmpty()) {
+            throw new ConstructorException(
+                    "Invalid file for '" + fileName + "': file name cannot be empty.");
+        }
+
+        int lastDotIndex = actualFileName.lastIndexOf('.');
+        if (lastDotIndex == -1 || lastDotIndex == actualFileName.length() - 1) {
+            throw new ConstructorException(
+                    "Invalid file for '"
+                            + fileName
+                            + "': file must have "
+                            + VALID_CATALOG_EXTENSIONS
+                            + " extension. Found: "
+                            + actualFileName);
+        }
+
+        String extension = actualFileName.substring(lastDotIndex).toLowerCase();
+
+        if (!VALID_CATALOG_EXTENSIONS.contains(extension)) {
+            throw new ConstructorException(
+                    "Invalid file type for '"
+                            + fileName
+                            + "': file must have "
+                            + VALID_CATALOG_EXTENSIONS
+                            + " extension. Found: "
+                            + actualFileName);
+        }
+
+        return extension;
+    }
+
     /**
      * Grabs the version number (hard coded ATM)
      *
@@ -2320,9 +2373,12 @@ protected static JSONArray transformItemsAPIV2Response(JSONArray results) {
     /**
      * Send a full catalog to replace the current one (sync)
      *
-     * @param req the catalog request
-     * @return a string of JSON
-     * @throws ConstructorException if the request is invalid.
+     * <p>Supports CSV, JSON, and JSONL file formats. The file type is automatically detected from
+     * the file extension (.csv, .json, or .jsonl).
+     *
+     * @param req the catalog request containing files with .csv, .json, or .jsonl extensions
+     * @return a string of JSON containing task information
+     * @throws ConstructorException if the request is invalid or file extensions are not supported
      */
     public String replaceCatalog(CatalogRequest req) throws ConstructorException {
         try {
@@ -2348,10 +2404,11 @@ public String replaceCatalog(CatalogRequest req) throws ConstructorException {
                 for (Map.Entry<String, File> entry : files.entrySet()) {
                     String fileName = entry.getKey();
                     File file = entry.getValue();
+                    String fileExtension = getValidatedFileExtension(file, fileName);
 
                     multipartBuilder.addFormDataPart(
                             fileName,
-                            fileName + ".csv",
+                            fileName + fileExtension,
                             RequestBody.create(MediaType.parse("application/octet-stream"), file));
                 }
             }
@@ -2377,9 +2434,12 @@ public String replaceCatalog(CatalogRequest req) throws ConstructorException {
     /**
      * Send a partial catalog to update specific items (delta)
      *
-     * @param req the catalog request
-     * @return a string of JSON
-     * @throws ConstructorException if the request is invalid.
+     * <p>Supports CSV, JSON, and JSONL file formats. The file type is automatically detected from
+     * the file extension (.csv, .json, or .jsonl).
+     *
+     * @param req the catalog request containing files with .csv, .json, or .jsonl extensions
+     * @return a string of JSON containing task information
+     * @throws ConstructorException if the request is invalid or file extensions are not supported
      */
     public String updateCatalog(CatalogRequest req) throws ConstructorException {
         try {
@@ -2405,10 +2465,11 @@ public String updateCatalog(CatalogRequest req) throws ConstructorException {
                 for (Map.Entry<String, File> entry : files.entrySet()) {
                     String fileName = entry.getKey();
                     File file = entry.getValue();
+                    String fileExtension = getValidatedFileExtension(file, fileName);
 
                     multipartBuilder.addFormDataPart(
                             fileName,
-                            fileName + ".csv",
+                            fileName + fileExtension,
                             RequestBody.create(MediaType.parse("application/octet-stream"), file));
                 }
             }
@@ -2435,9 +2496,12 @@ public String updateCatalog(CatalogRequest req) throws ConstructorException {
     /**
      * Send a patch delta catalog to update specific items (delta)
      *
-     * @param req the catalog request
-     * @return a string of JSON
-     * @throws ConstructorException if the request is invalid.
+     * <p>Supports CSV, JSON, and JSONL file formats. The file type is automatically detected from
+     * the file extension (.csv, .json, or .jsonl).
+     *
+     * @param req the catalog request containing files with .csv, .json, or .jsonl extensions
+     * @return a string of JSON containing task information
+     * @throws ConstructorException if the request is invalid or file extensions are not supported
      */
     public String patchCatalog(CatalogRequest req) throws ConstructorException {
         try {
@@ -2468,10 +2532,11 @@ public String patchCatalog(CatalogRequest req) throws ConstructorException {
                 for (Map.Entry<String, File> entry : files.entrySet()) {
                     String fileName = entry.getKey();
                     File file = entry.getValue();
+                    String fileExtension = getValidatedFileExtension(file, fileName);
 
                     multipartBuilder.addFormDataPart(
                             fileName,
-                            fileName + ".csv",
+                            fileName + fileExtension,
                             RequestBody.create(MediaType.parse("application/octet-stream"), file));
                 }
             }