René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Add a --cors command line option to stdlib http.server","articleBody":"# Feature or enhancement\n\n### Proposal:\n\nAdd a `--cors` command line option to the `http.server` stdlib module, which when specified will add this CORS header to all responses:\n```\nAccess-Control-Allow-Origin: *\n```\n\nThis is useful during local web development, which is a common use case for `http.server`. If a user is developing Javascript on one local web server, and making Javascript requests against static assets served by a separately running `python -m http.server`, those requests will fail due to the browser's default cross-origin request policy. With the rise in popularity of tools like pyodide and pyscript, whose implementations are subject to the same Javascript cross-origin request logic, I expect similar use cases to this to become more common. It would be useful for `http.server` to support an open cross-origin response header via the command line like so:\n\n```shell\npython -m http.server --cors\n```\n\nThis allows the user to serve static assets locally that can be requested by Javascript anywhere the server is visible. The new headers are opt-in only, no default behavior is changed without the flag.\n\n### Has this already been discussed elsewhere?\n\nI have already discussed this feature proposal on Discourse\n\n### Links to previous discussion of this feature:\n\nI started a thread about this feature on python-ideas:\nhttps://discuss.python.org/t/any-interest-in-adding-a-cors-option-to-python-m-http-server/92120/10\n\nThe thread has a mixed response. Some are for it, some against, and some are in favor of a more generalized approach. I discussed the feature with some developers in person at Pycon 2025, the result being that there is possibly enough interest to add this feature. \n\n\u003c!-- gh-linked-prs -->\n### Linked PRs\n* gh-135057\n* gh-149320\n\u003c!-- /gh-linked-prs -->\n","author":{"url":"https://github.com/aisipos","@type":"Person","name":"aisipos"},"datePublished":"2025-06-03T04:38:05Z","url":"https://github.com/python/cpython/issues/135056"}