Specify path instead of actually uploading file

dp_wizard/shiny/__init__.py

@@ -103,7 +103,7 @@ def server(input: Inputs, output: Outputs, session: Session):  # pragma: no cove
         private_csv_path = reactive.value(str(initial_private_csv_path))
         column_names = reactive.value(initial_column_names)
 
-        public_csv_path = reactive.value("")
+        public_csv_path = reactive.value(None)
         analysis_types = reactive.value({})
         lower_bounds = reactive.value({})
         upper_bounds = reactive.value({})
@@ -123,7 +123,6 @@ def server(input: Inputs, output: Outputs, session: Session):  # pragma: no cove
             session,
             is_demo=cli_info.is_demo,
             in_cloud=cli_info.in_cloud,
-            initial_public_csv_path="",
             initial_private_csv_path=str(initial_private_csv_path),
             public_csv_path=public_csv_path,
             private_csv_path=private_csv_path,

dp_wizard/shiny/components/inputs.py

@@ -1,7 +1,31 @@
+from pathlib import Path
 from math import log10
 from shiny import ui
 
 
+parent_name = "../"
+
+
+def get_file_selector_choices(cwd: Path):
+    return [None, parent_name] + sorted(
+        path.name + ("/" if path.is_dir() else "")
+        for path in cwd.iterdir()
+        if path.name.endswith(".csv") or path.is_dir()
+    )
+
+
+def file_selector(id: str, label: str, cwd: Path):
+    from dp_wizard.shiny.components.outputs import info_md_box
+
+    return ui.input_select(
+        id,
+        [label, " from:", ui.tags.br(), ui.tags.strong(cwd.name + "/")],
+        get_file_selector_choices(cwd),
+        size="6",
+        selected=None,
+    )
+
+
 def log_slider(id: str, lower_bound: float, upper_bound: float):
     # Rather than engineer a new widget, hide the numbers we don't want,
     # and insert the log values via CSS.

dp_wizard/shiny/dataset_panel.py

@@ -9,6 +9,11 @@
     PUBLIC_PRIVATE_TEXT,
 )
 from dp_wizard.utils.csv_helper import get_csv_names_mismatch
+from dp_wizard.shiny.components.inputs import (
+    get_file_selector_choices,
+    file_selector,
+    parent_name,
+)
 from dp_wizard.shiny.components.outputs import (
     output_code_sample,
     demo_tooltip,
@@ -51,19 +56,40 @@ def dataset_server(
     session: Session,
     is_demo: bool,
     in_cloud: bool,
-    initial_public_csv_path: str,
     initial_private_csv_path: str,
-    public_csv_path: reactive.Value[str],
+    public_csv_path: reactive.Value[Path | None],
     private_csv_path: reactive.Value[str],
     column_names: reactive.Value[list[str]],
     contributions: reactive.Value[int],
 ):  # pragma: no cover
+    public_csv_dir = reactive.value(Path.cwd())
+
     @reactive.effect
-    @reactive.event(input.public_csv_path)
-    def _on_public_csv_path_change():
-        path = input.public_csv_path()[0]["datapath"]
-        public_csv_path.set(path)
-        column_names.set(read_csv_names(Path(path)))
+    @reactive.event(input.public_csv_name)
+    def _on_public_csv_name_change():
+        name = input.public_csv_name()
+        if not name:
+            column_names.set([])
+        elif name == parent_name:
+            new_dir = public_csv_dir().parent
+            public_csv_dir.set(new_dir)
+            public_csv_path.set(None)
+            ui.update_select(
+                "public_csv_name", choices=get_file_selector_choices(new_dir)
+            )
+            column_names.set([])
+        elif name.endswith("/"):
+            new_dir = public_csv_dir() / name
+            public_csv_dir.set(new_dir)
+            public_csv_path.set(None)
+            ui.update_select(
+                "public_csv_name", choices=get_file_selector_choices(new_dir)
+            )
+            column_names.set([])
+        else:
+            new_path = public_csv_dir() / name
+            public_csv_path.set(new_path)
+            column_names.set(read_csv_names(new_path))
 
     @reactive.effect
     @reactive.event(input.private_csv_path)
@@ -157,12 +183,7 @@ def input_files_ui():
         # - After file upload, the internal copy of the file
         #   is renamed to something like "0.csv".
         return ui.row(
-            ui.input_file(
-                "public_csv_path",
-                "Choose Public CSV",
-                accept=[".csv"],
-                placeholder=Path(initial_public_csv_path).name,
-            ),
+            file_selector("public_csv_name", "Choose Public CSV", public_csv_dir()),
             ui.input_file(
                 "private_csv_path",
                 [