Migrate static file serving e2e test to playwright (streamlit#8811)

## Describe your changes

This PR migrates the static file serving e2e test to playwright.

---

**Contribution License Agreement**

By submitting this pull request you agree that all contributions to this
project are made under the Apache 2.0 license.

e2e/scripts/staticfiles_apps/streamlit_static_app.py → e2e_playwright/config_static_serving.py

@@ -13,26 +13,16 @@
 # limitations under the License.
 
 import streamlit as st
-from streamlit import runtime
-
-st.header("Main Page with static files")
 
 if not st.get_option("server.enableStaticServing"):
     st.error(
-        """
-        **ERROR**. This test needs to be run with `--server.enableStaticServing`, like
-        this:
+        "**ERROR**. This test needs to be run with `--server.enableStaticServing`."
+    )
 
-        ```
-        streamlit run
-            e2e/scripts/staticfiles_apps/streamlit_static_app.py
-            --server.enableStaticServing=true
-        ```
+st.markdown(
     """
-    )
+Images served via static serving:
 
-elif runtime.exists():
-    """Static files serving works only when runtime exists"""
-    st.markdown(
-        "![Streamlit](http://localhost:8501/app/static/streamlit-mark-color.png)"
-    )
+![Streamlit](./app/static/streamlit-logo.png)
+"""
+)

e2e_playwright/config_static_serving_test.py

@@ -0,0 +1,47 @@
+# Copyright (c) Streamlit Inc. (2018-2022) Snowflake Inc. (2022-2024)
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from playwright.sync_api import Page, expect
+
+from e2e_playwright.shared.app_utils import get_markdown
+
+
+def test_should_serve_existing_asset(app: Page, app_port: int):
+    """Test that the static serving feature serves an existing asset."""
+    response = app.request.get(
+        f"http://localhost:{app_port}/app/static/streamlit-logo.png"
+    )
+    expect(response).to_be_ok()
+    # Assert is safe here since we don't need to wait for something here:
+    assert response.status == 200
+
+
+def test_should_return_error_on_non_existing_asset(app: Page, app_port: int):
+    """Test that the static serving feature returns error code for non-existing asset."""
+    response = app.request.get(
+        f"http://localhost:{app_port}/app/static/notexisting.jpeg"
+    )
+    expect(response).not_to_be_ok()
+    # Assert is safe here since we don't need to wait for something here:
+    assert response.status == 404
+
+
+def test_static_served_image_embedded_in_markdown(app: Page):
+    """Test that an image served via the static serving can be embedded into markdown."""
+    markdown_element = get_markdown(app, "Images served via static serving:")
+    image_element = markdown_element.locator("img")
+
+    expect(image_element).to_be_visible()
+    # Check that the image gets loaded correctly
+    app.expect_response("**/streamlit-logo.png")

e2e_playwright/conftest.py

@@ -231,6 +231,8 @@ def app_server(
             "false",
             "--server.fileWatcherType",
             "none",
+            "--server.enableStaticServing",
+            "true",
         ],
         cwd=".",
     )

e2e_playwright/shared/app_utils.py

@@ -116,6 +116,30 @@ def get_expander(locator: Locator, label: str | Pattern[str]) -> Locator:
     return element
 
 
+def get_markdown(locator: Locator, text_inside_markdown: str | Pattern[str]) -> Locator:
+    """Get a markdown element with the given text inside.
+    Parameters
+    ----------
+    locator : Locator
+        The locator to search for the expander.
+    text_inside_markdown : str or Pattern[str]
+        Some text to use to identify the markdown element. The text should be contained
+        in the markdown content.
+    Returns
+    -------
+    Locator
+        The expander content.
+    """
+    if isinstance(text_inside_markdown, str):
+        text_inside_markdown = re.compile(text_inside_markdown)
+
+    markdown_element = locator.get_by_test_id("stMarkdownContainer").filter(
+        has_text=text_inside_markdown
+    )
+    expect(markdown_element).to_be_visible()
+    return markdown_element
+
+
 def expect_prefixed_markdown(
     locator: Locator,
     expected_prefix: str,

scripts/run_e2e_tests.py

@@ -412,27 +412,6 @@ def run_e2e_tests(
                     show_output=verbose,
                 )
 
-            elif basename(spec_path) == "staticfiles_app.spec.js":
-                test_name, _ = splitext(basename(spec_path))
-                test_name, _ = splitext(test_name)
-                test_path = join(
-                    ctx.tests_dir,
-                    "scripts",
-                    "staticfiles_apps",
-                    "streamlit_static_app.py",
-                )
-                if os.path.exists(test_path):
-                    run_test(
-                        ctx,
-                        str(spec_path),
-                        [
-                            "streamlit",
-                            "run",
-                            "--server.enableStaticServing=true",
-                            test_path,
-                        ],
-                        show_output=verbose,
-                    )
             elif basename(spec_path) == "hostframe.spec.js":
                 test_name, _ = splitext(basename(spec_path))
                 test_name, _ = splitext(test_name)