Add Streamlit support to Python Extensions (Experimental)

[Copilot]

Adds AddStreamlitApp() extension method to host Streamlit applications in Aspire, using the Aspire.Hosting.Python integration.

Implementation

• StreamlitAppResource: Resource definition inheriting from PythonAppResource with service discovery support
• StreamlitAppHostingExtension: Extension method using AddPythonExecutable from Aspire.Hosting.Python
  • Configures Streamlit server with proper port, address, and headless mode settings
  • Supports virtual environment management via WithPip(), WithUv(), and WithVirtualEnvironment()
• Experimental Status: Marked with [Experimental("CTASPIRE001")] attribute as it relies on patterns that will be publicly exposed in Aspire 13.1

Usage

builder.AddStreamlitApp("myapp", "../path/to/app", "app.py")
    .WithHttpEndpoint(env: "PORT")
    .WithHttpHealthCheck("/health");

Note: This integration is experimental and subject to change. The implementation will be updated when AddPythonAppCore becomes publicly available in Aspire.Hosting.Python (expected in Aspire 13.1).

Testing

• Added unit test validating resource creation

• Added integration test to AppHost example (currently skipped per issue Review the Python extensions relative to the new Python hosting integration #917)

• Included minimal Streamlit example app in examples/python/streamlit-api/

• Experimental diagnostic warnings suppressed in tests and examples

• Fixes Add Streamlit to PythonExtention #953

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Add Streamlit to PythonExtention</issue_title>
<issue_description>### Related to an existing integration?

Yes

Existing integration

CommunityToolkit.Aspire.Hosting.Python.Extensions

Overview

We should add support in the Python Extension for streamlit. The extension is basically a wrapper around AddExecutable with the hardcoded command streamlit. A streamlit app is executed by running
streamlit run your_file.py, so we want to probably use the same structure we use for golang.

Usage example

The first parameter is of course the aspire resource name. Second param is the working directory and third param is the python file to be run by streamlit.

builder.AddStreamlitApp("myapp", "../path/to/app", "app.py")
    .WithHttpEndpoint(env: "PORT")
    .WithHttpHealthCheck("/health");

Breaking change?

No

Alternatives

You can use AddExecutable to manually set the commands.

Additional context

No response

Help us help you

Yes, I'd like to be assigned to work on this item</issue_description>

Comments on the Issue (you are @copilot in this section)

Custom agent used: Hosting Integration Creator
This agent helps users create new hosting integration in Aspire by scaffolding the correct projects and files based on user input.

• Fixes Add Streamlit to PythonExtention #953

---

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[tommasodotNET]

@copilot work on the review comments

[Copilot]

Pull Request Overview

This PR adds Streamlit support to the Python Extensions for .NET Aspire, allowing developers to host Streamlit applications within Aspire. This includes the resource definition, hosting extension methods, example application, and tests.

• Adds StreamlitAppResource and StreamlitAppHostingExtension for Streamlit support
• Includes a working example Streamlit application with proper setup documentation
• Adds test coverage for both resource creation and integration testing

Reviewed Changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
StreamlitAppResource.cs	Defines the Streamlit application resource model
StreamlitAppHostingExtension.cs	Provides extension methods to add Streamlit apps to the app builder
ResourceCreationTests.cs	Adds unit test for Streamlit resource creation
AppHostTests.cs	Adds integration test for Streamlit app startup
README.md (extensions)	Documents Streamlit usage example
Program.cs (AppHost)	Adds Streamlit app to the example host
streamlit-api/*	Example Streamlit application with dependencies and documentation

[davidfowl]

Does debugging and deploying work?

[aaronpowell]

I wouldn't invest in that until 13.1 when we can drop our implementation of the internals of the Python integration.

[davidfowl]

I think we should make sure it works. The bar should be higher in 13 for new language / framework integrations. Even if it doesn't work I don't want us to merge things without understanding what works and what doesn't work. I'd expect the future to look like a set of capabililities for these language integrations (otel support, endpoints, https, dockerfile, debugging). Doing enough work to know what we will document is a minimum bar here.

[aaronpowell]

While I appreciate the desire, we have to work with the realities of the OSS project - we don't have the resources to do everything that Aspire does.

The goal is to do our best to be producing high quality integrations to the level of Aspire, but it's not always going to be the case, especially if we want to ship. Feel free to raise an issue to get debugger support enabled, but I don't see it as a blocker for us shipping.

[davidfowl]

Ok let me ask then. Does it work when you run locally and deploy? If it doesn’t? Do we know why? Has anyone built an app with this PR?

[github-actions]

Package	Line Rate	Branch Rate	Complexity	Health
CommunityToolkit.Aspire.GoFeatureFlag	100%	97%	74	✔
CommunityToolkit.Aspire.Hosting.ActiveMQ	78%	40%	108	➖
CommunityToolkit.Aspire.Hosting.ActiveMQ.MassTransit	1%	0%	14	❌
CommunityToolkit.Aspire.Hosting.Adminer	73%	50%	20	➖
CommunityToolkit.Aspire.Hosting.Azure.Dapr	29%	7%	124	❌
CommunityToolkit.Aspire.Hosting.Azure.Dapr.Redis	61%	34%	76	➖
CommunityToolkit.Aspire.Hosting.Azure.DataApiBuilder	100%	100%	22	✔
CommunityToolkit.Aspire.Hosting.Bun	96%	83%	28	✔
CommunityToolkit.Aspire.Hosting.Dapr	60%	37%	840	❌
CommunityToolkit.Aspire.Hosting.DbGate	94%	50%	18	✔
CommunityToolkit.Aspire.Hosting.Deno	98%	85%	44	✔
CommunityToolkit.Aspire.Hosting.Flagd	79%	100%	32	➖
CommunityToolkit.Aspire.Hosting.GoFeatureFlag	87%	73%	36	✔
CommunityToolkit.Aspire.Hosting.Golang	87%	70%	28	✔
CommunityToolkit.Aspire.Hosting.Java	70%	75%	130	➖
CommunityToolkit.Aspire.Hosting.JavaScript.Extensions	97%	85%	200	✔
CommunityToolkit.Aspire.Hosting.k6	58%	12%	20	❌
CommunityToolkit.Aspire.Hosting.Keycloak.Extensions	100%	100%	22	✔
CommunityToolkit.Aspire.Hosting.KurrentDB	71%	75%	34	➖
CommunityToolkit.Aspire.Hosting.LavinMQ	74%	50%	26	➖
CommunityToolkit.Aspire.Hosting.LavinMQ.MassTransit	1%	0%	14	❌
CommunityToolkit.Aspire.Hosting.MailPit	85%	50%	22	✔
CommunityToolkit.Aspire.Hosting.McpInspector	75%	39%	150	➖
CommunityToolkit.Aspire.Hosting.Meilisearch	71%	57%	58	➖
CommunityToolkit.Aspire.Hosting.Minio	88%	75%	56	✔
CommunityToolkit.Aspire.Hosting.MongoDB.Extensions	96%	83%	36	✔
CommunityToolkit.Aspire.Hosting.MySql.Extensions	100%	88%	78	✔
CommunityToolkit.Aspire.Hosting.Ngrok	52%	35%	82	❌
CommunityToolkit.Aspire.Hosting.Ollama	65%	70%	200	➖
CommunityToolkit.Aspire.Hosting.OpenTelemetryCollector	78%	61%	77	➖
CommunityToolkit.Aspire.Hosting.PapercutSmtp	81%	50%	18	✔
CommunityToolkit.Aspire.Hosting.PostgreSQL.Extensions	99%	89%	84	✔
CommunityToolkit.Aspire.Hosting.Python.Extensions	45%	29%	100	❌
CommunityToolkit.Aspire.Hosting.RavenDB	62%	48%	148	➖
CommunityToolkit.Aspire.Hosting.Redis.Extensions	100%	71%	48	✔
CommunityToolkit.Aspire.Hosting.Rust	94%	83%	16	✔
CommunityToolkit.Aspire.Hosting.Solr	72%	100%	22	➖
CommunityToolkit.Aspire.Hosting.SqlDatabaseProjects	52%	49%	206	❌
CommunityToolkit.Aspire.Hosting.Sqlite	89%	89%	52	✔
CommunityToolkit.Aspire.Hosting.SqlServer.Extensions	100%	87%	78	✔
CommunityToolkit.Aspire.Hosting.SurrealDb	55%	40%	256	❌
CommunityToolkit.Aspire.KurrentDB	94%	92%	54	✔
CommunityToolkit.Aspire.MassTransit.RabbitMQ	100%	100%	30	✔
CommunityToolkit.Aspire.Meilisearch	97%	92%	68	✔
CommunityToolkit.Aspire.Microsoft.Data.Sqlite	89%	85%	52	✔
CommunityToolkit.Aspire.Microsoft.EntityFrameworkCore.Sqlite	61%	58%	114	➖
CommunityToolkit.Aspire.Minio.Client	90%	85%	112	✔
CommunityToolkit.Aspire.OllamaSharp	77%	71%	132	➖
CommunityToolkit.Aspire.RavenDB.Client	60%	53%	237	➖
CommunityToolkit.Aspire.SurrealDb	79%	63%	78	➖
Summary	68% (7067 / 10350)	56% (2012 / 3590)	4574	➖

Minimum allowed line rate is 60%