fix: url creation

[HamzaNa1]

This fixes #1238

I updated the name of the env variable from EXPO_PUBLIC_SERVER_ORIGIN to EXPO_PUBLIC_SERVER_URL since that is the name the docs mentions

Previously the code checked if window.location is defined, which threw an error because window did not exist, this caused it to fallback to the default URL without checking the env variable

The new code will check if the env variable FIRST and use it if it exists, then check safely for the window and then for the debuggerHost

Summary by CodeRabbit

• Bug Fixes

  • Improved server URL resolution to safely prefer the browser origin when available and reliably fall back to the debugger host when needed (avoids errors when a browser environment is absent).

• Chores

  • Replaced EXPO_PUBLIC_SERVER_ORIGIN with EXPO_PUBLIC_SERVER_URL for deriving the app’s server URL.
  • Updated default resolution and runtime warnings to reference the new variable and clarify configuration expectations.

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: 3f65cee9c2200f08b1b1d6b7565157521f80f862

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@uploadthing/expo	Patch

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[coderabbitai[bot]]

Walkthrough

Replaces use of EXPO_PUBLIC_SERVER_ORIGIN with EXPO_PUBLIC_SERVER_URL and updates URL resolution to prefer EXPO_PUBLIC_SERVER_URL, then window.location.origin (when available), then http://{debuggerHost}. Adjusts warning message accordingly. No exported/public API changes.

Changes

Cohort / File(s)	Summary
Expo URL resolution packages/expo/src/index.ts	Switched env var from EXPO_PUBLIC_SERVER_ORIGIN to EXPO_PUBLIC_SERVER_URL; updated URL construction fallback order (env → window.location.origin → http://{debuggerHost}); revised warning message text; minor structural alignment in URL construction.

Sequence Diagram(s)

sequenceDiagram
  autonumber
  participant App
  participant ExpoPkg as uploadthing/expo
  participant Env as process.env
  participant Window as window.location
  participant Debugger as debuggerHost

  App->>ExpoPkg: generateReactNativeHelpers(initOpts)
  Note over ExpoPkg: Build base URL
  ExpoPkg->>Env: Read EXPO_PUBLIC_SERVER_URL
  alt EXPO_PUBLIC_SERVER_URL set
    ExpoPkg->>ExpoPkg: Use env URL (absolute or resolve relative)
  else not set
    ExpoPkg->>Window: Check window.location.origin
    alt window available
      ExpoPkg->>ExpoPkg: Use window.location.origin
    else no window
      ExpoPkg->>Debugger: Use http://{debuggerHost}
    end
  end
  ExpoPkg-->>App: Resolved URL (or warn on failure)
  Note right of ExpoPkg: Warning references EXPO_PUBLIC_SERVER_URL

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Pre-merge checks and finishing touches

❌ Failed checks (1 inconclusive)

Check name	Status	Explanation	Resolution
Title Check	❓ Inconclusive	The title “fix: url creation” indicates a fix related to URL construction but is overly generic and does not clearly convey the primary changes around renaming the environment variable and updating the URL resolution logic. It only partially reflects the scope of the PR and may not immediately inform reviewers or future readers of the key modifications. Therefore, it is inconclusive whether this title sufficiently captures the main change.	Consider updating the title to explicitly reference the environment variable rename and the updated URL resolution logic, for example: “fix: use EXPO_PUBLIC_SERVER_URL and update URL fallback logic”.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Linked Issues Check	✅ Passed	The changes rename the environment variable to EXPO_PUBLIC_SERVER_URL, update the URL resolution order to check the env variable before safely handling window availability, and adjust the warning message accordingly, fully addressing the coding requirements outlined in issue #1238.
Out of Scope Changes Check	✅ Passed	All modifications are confined to the URL construction logic in packages/expo/src/index.ts, directly targeting the env variable rename and resolution flow described in the linked issue with no unrelated or extraneous changes.
Docstring Coverage	✅ Passed	No functions found in the changes. Docstring coverage check skipped.

✨ Finishing touches

• [ ] 📝 Generate docstrings

🧪 Generate unit tests (beta)

• [ ] Create PR with unit tests
• [ ] Post copyable unit tests in a comment

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Project	Deployment	Preview	Comments	Updated (UTC)
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[markflorkowski]

Update examples and turbo.json.

Keep old (incorrect) variable as a potential fallback to prevent issues for anyone who worked around this previously