support non-ASCII filesystem bundle paths with metro server#1538
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bradleyayers wants to merge 1 commit intofacebook:mainfrom
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support non-ASCII filesystem bundle paths with metro server#1538bradleyayers wants to merge 1 commit intofacebook:mainfrom
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In a codebase with non-ascii characters in file paths (e.g. Japanese or Chinese characters), metro has an error when serving bundles: ``` TypeError: Invalid character in header content ``` This was reported in the Expo project expo/expo#27397 but it's not Expo code and was later closed. The problem is fairly simple—HTTP headers need to use ASCII characters only, but filesystems are not limited to ASCII so trying to put a filesystem path directly into a HTTP header value is going to cause a problem. The solution also seems relatively simple—URL encode the path so that it uses percent encoding of non-ASCII characters. I did three tests of this code, looking at the response headers for the chunk served by metro to look for backwards compatibility of using `new URL(…)` on paths that don't use non-ASCII characters. ``` with new URL(…) patch and /你/ path segment Content-Location: http://localhost:8081/projects/app/src/client/wiki/%E4%BD%A0/hello.bundle//&platform=web&dev=true&hot=false&lazy=true&transform.routerRoot=src%2Fapp&transform.reactCompiler=true&modulesOnly=true&runModule=false --- with new URL(…) and /ni/ path segment Content-Location: http://localhost:8081/projects/app/src/client/wiki/ni/hello.bundle//&platform=web&dev=true&hot=false&lazy=true&transform.routerRoot=src%2Fapp&transform.reactCompiler=true&modulesOnly=true&runModule=false --- original code with /ni/ path segment Content-Location: http://localhost:8081/projects/app/src/client/wiki/ni/hello.bundle//&platform=web&dev=true&hot=false&lazy=true&transform.routerRoot=src%2Fapp&transform.reactCompiler=true&modulesOnly=true&runModule=false ``` This demonstrates that it's backwards compatible, while properly encoding non-ASCII characters.
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…#1538) Summary: In a codebase with non-ascii characters in file paths (e.g. Japanese or Chinese characters), metro has an error when serving bundles: ``` TypeError: Invalid character in header content ``` This was reported in the Expo project expo/expo#27397 but it's not Expo code and was later closed. The problem is fairly simple—HTTP headers need to use ASCII characters only, but filesystems are not limited to ASCII so trying to put a filesystem path directly into a HTTP header value is going to cause a problem. The solution also seems relatively simple—URL encode the path so that it uses percent encoding of non-ASCII characters. As suggested in https://velog.io/demian/RN-%EC%98%A4%EB%A5%98-%ED%95%B4%EA%B2%B0-TypeError-Invalid-character-in-header-content-X-React-Native-Project-Root, some people were adding the following middleware to fix that issue: ``` function createMetroStatusMiddleware(metroConfig) { return (_req, res)=>{ res.setHeader("X-React-Native-Project-Root", new URL(metroConfig.projectRoot)); res.end("packager-status:running"); }; } ``` Instead, I went to the root cause, and improved the parsing of the URL for both `sourceUrl` and `sourceMapUrl` fixing both the issue with serving bundles and the issue with serving source maps. > **_NOTE:_** this problem stems from using the [deprecated `url.parse` instead of the newer URL](https://nodejs.org/api/url.html#urlparseurlstring-parsequerystring-slashesdenotehost). Changelog: [General][Fixed] Metro supporting non-ASCII bundle/sourcemaps paths Pull Request resolved: facebook#1538 Test Plan: Using a test diff D78806803 I managed to reproduce Metro not launching RNTester before this diff. 1. `buck2 install -r rntester-android` (with the modified bundle path) 2. `DEV=1 js1 run` 3. launch `RNTester` Before- app crashes: https://pxl.cl/7LFkb After- app launches, debugging works: {F1980565661} can even add the bundle to ignore-list and then it gets ignored: {F1980565660} Differential Revision: D78799358
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Note This PR was modified by @vzaidman and merged in 92ac74c with a more upstream decoding of URLs to prevent non-ASCII from crashing Metro. However, while Metro would now indeed not crash, Metro doesn't fully support non-ASCII files as of this PR. Instead, the later merged commit cb02cdb adds a comprehensive support to non-ASCII in Metro with tests. The split into two PRs is intended to credit the author of this PR and to allow us to revert the latter more complex code without removing this fix. |
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Note
This PR was modified by @vzaidman and merged in 92ac74c with a more upstream decoding of URLs to prevent non-ASCII from crashing Metro.
However, while Metro would now indeed not crash, Metro doesn't fully support non-ASCII files as of this PR.
Instead, the later merged commit cb02cdb adds a comprehensive support to non-ASCII in Metro with tests.
The split into two PRs is intended to credit the author of this PR and to allow us to revert the latter more complex code without removing this fix.
Also see subsequent commits: 71e158a and 98badca
In a codebase with non-ascii characters in file paths (e.g. Japanese or Chinese characters), metro has an error when serving bundles:
This was reported in the Expo project expo/expo#27397 but it's not Expo code and was later closed.
The problem is fairly simple—HTTP headers need to use ASCII characters only, but filesystems are not limited to ASCII so trying to put a filesystem path directly into a HTTP header value is going to cause a problem.
The solution also seems relatively simple—URL encode the path so that it uses percent encoding of non-ASCII characters.
I did three tests of this code, looking at the response headers for the chunk served by metro to look for backwards compatibility of using
new URL(…)on paths that don't use non-ASCII characters.This demonstrates that it's backwards compatible, while properly encoding non-ASCII characters.
Summary
Changelog: [Fix] non-ascii files processed by Metro no longer crash the server