feat: Add support for uploading files as a list

Uploading a list of files with the same key is supported by the Requests library.
This allows the receiving server to accept a list of files for the same key, i.e. accepting any number of files.
Issue: #401

Author: Thomas Vanhaniemi

atests/http_server/helpers.py

@@ -110,15 +110,16 @@ def get_files():
 
     files = dict()
 
-    for k, v in request.files.items():
-        content_type = request.files[k].content_type or 'application/octet-stream'
-        val = json_safe(v.read(), content_type)
-        if files.get(k):
-            if not isinstance(files[k], list):
-                files[k] = [files[k]]
-            files[k].append(val)
-        else:
-            files[k] = val
+    for k in request.files.keys():
+        for v in request.files.getlist(k):
+            content_type = v.content_type or 'application/octet-stream'
+            val = json_safe(v.read(), content_type)
+            if files.get(k):
+                if not isinstance(files[k], list):
+                    files[k] = [files[k]]
+                files[k].append(val)
+            else:
+                files[k] = val
 
     return files
 

atests/test_post_multipart.robot

@@ -3,7 +3,7 @@ Library     RequestsLibrary
 
 
 *** Test Cases ***
-Test Post On Session Multipart
+Test Post Dictionary On Session Multipart
     ${file_1}=    Get File For Streaming Upload    atests/randombytes.bin
     ${file_2}=    Get File For Streaming Upload    atests/randombytes.bin
     ${files}=    Create Dictionary    randombytes1    ${file_1}    randombytes2    ${file_2}
@@ -14,3 +14,19 @@ Test Post On Session Multipart
     Should Contain    ${resp.json()}[headers][Content-Length]    480
     Should Contain    ${resp.json()}[files]    randombytes1
     Should Contain    ${resp.json()}[files]    randombytes2
+
+Test Post List On Session Multipart
+    ${file_1}=    Get File For Streaming Upload    atests/randombytes.bin
+    ${file_2}=    Get File For Streaming Upload    atests/randombytes.bin
+    ${file_1_tuple}=    Create List     file1.bin   ${file_1}
+    ${file_2_tuple}=    Create List     file2.bin   ${file_2}
+    ${file_1_upload}=    Create List    randombytes    ${file_1_tuple}
+    ${file_2_upload}=    Create List    randombytes    ${file_2_tuple}
+    ${files}=    Create List    ${file_1_upload}    ${file_2_upload}
+
+    ${resp}=    POST On Session    ${GLOBAL_SESSION}    /anything    files=${files}
+
+    Should Contain    ${resp.json()}[headers][Content-Type]    multipart/form-data; boundary=
+    Should Contain    ${resp.json()}[headers][Content-Length]    466
+    Should Contain    ${resp.json()}[files]    randombytes
+    Length Should Be    ${resp.json()}[files][randombytes]    2

doc/RequestsLibrary.html

@@ -6,6 +6,7 @@
 from RequestsLibrary import log
 from RequestsLibrary.compat import urljoin
 from RequestsLibrary.utils import (
+    is_list_or_tuple,
     is_file_descriptor,
     warn_if_equal_symbol_in_url_session_less,
 )
@@ -48,9 +49,16 @@ def _common_request(self, method, session, uri, **kwargs):
 
         files = kwargs.get("files", {}) or {}
         data = kwargs.get("data", []) or []
-        files_descriptor_to_close = filter(
-            is_file_descriptor, list(files.values()) + [data]
-        )
+
+        if is_list_or_tuple(files):
+            files_descriptor_to_close = filter(
+                is_file_descriptor, [file[1][1] for file in files] + [data]
+            )
+        else:
+            files_descriptor_to_close = filter(
+                is_file_descriptor, list(files.values()) + [data]
+            )
+
         for file_descriptor in files_descriptor_to_close:
             file_descriptor.close()
 
@@ -176,7 +184,7 @@ def session_less_get(
         | ``json``     | A JSON serializable Python object to send in the body of the request. |
         | ``headers``  | Dictionary of HTTP Headers to send with the request. |
         | ``cookies``  | Dict or CookieJar object to send with the request. |
-        | ``files``    | Dictionary of file-like-objects (or ``{'name': file-tuple}``) for multipart encoding upload. ``file-tuple`` can be a 2-tuple ``('filename', fileobj)``, 3-tuple ``('filename', fileobj, 'content_type')`` or a 4-tuple ``('filename', fileobj, 'content_type', custom_headers)``, where ``'content-type'`` is a string defining the content type of the given file and ``custom_headers`` a dict-like object containing additional headers to add for the file. |
+        | ``files``    | Dictionary of file-like-objects (or ``{'name': file-tuple}``) for multipart encoding upload. ``file-tuple`` can be a 2-tuple ``('filename', fileobj)``, 3-tuple ``('filename', fileobj, 'content_type')`` or a 4-tuple ``('filename', fileobj, 'content_type', custom_headers)``, where ``'content-type'`` is a string defining the content type of the given file and ``custom_headers`` a dict-like object containing additional headers to add for the file. List or tuple of ``('key': file-tuple)`` allows uploading multiple files with the same key, resulting in a list of files on the receiving end. |
         | ``auth`` | Auth tuple to enable Basic/Digest/Custom HTTP Auth. |
         | ``timeout`` | How many seconds to wait for the server to send data before giving up, as a float, or a ``(connect timeout, read timeout)`` tuple. |
         | ``allow_redirects`` | Boolean. Enable/disable (values ``${True}`` or ``${False}``). Only for HEAD method keywords allow_redirection defaults to ``${False}``, all others ``${True}``. |

src/RequestsLibrary/RequestsKeywords.py

@@ -74,6 +74,8 @@ def is_string_type(data):
 def is_file_descriptor(fd):
     return isinstance(fd, io.IOBase)
 
+def is_list_or_tuple(data):
+    return isinstance(data, (list, tuple))
 
 def utf8_urlencode(data):
     if is_string_type(data):