Auto-reconnect PackagerConnection to Metro dev server (#56625)#56625
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javache wants to merge 1 commit into
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Auto-reconnect PackagerConnection to Metro dev server (#56625)#56625javache wants to merge 1 commit into
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Summary: When MWA starts before Metro is running, PackagerConnection's WebSocket connection to Metro's `/message` endpoint silently fails with no retry. The developer must restart MWA after starting Metro to get HMR working. This diff adds reconnection logic to PackagerConnection so it automatically retries when Metro becomes available. On initial connect failure or WebSocket disconnect, PackagerConnection schedules a retry after 5 seconds using the existing `WebSocketClientFactory` to create a fresh client. On successful reconnect, it fires `liveReloadCallback_()` which triggers `FoxReactHost::reloadReactInstance()` to load the bundle from Metro and set up HMR. The reconnection is event-driven: each retry is a short-lived thread that sleeps 5 seconds then calls `attemptConnection()`. The connect callback handles success/failure — no long-lived polling thread. The `active_` flag is set to false in the destructor to stop retries during shutdown. Combined with D97570592's push-based route invalidation, this completes the dev loop: Metro can start at any time, PackagerConnection auto-reconnects, HMR keeps the bundle fresh, and route changes propagate automatically. Reviewed By: christophpurrer Differential Revision: D97823787
Summary: When MWA starts before Metro is running, PackagerConnection's WebSocket connection to Metro's `/message` endpoint silently fails with no retry. The developer must restart MWA after starting Metro to get HMR working. This diff adds reconnection logic to PackagerConnection so it automatically retries when Metro becomes available. On initial connect failure or WebSocket disconnect, PackagerConnection schedules a retry after 5 seconds using the existing `WebSocketClientFactory` to create a fresh client. On successful reconnect, it fires `liveReloadCallback_()` which triggers `FoxReactHost::reloadReactInstance()` to load the bundle from Metro and set up HMR. The reconnection is event-driven: each retry is a short-lived thread that sleeps 5 seconds then calls `attemptConnection()`. The connect callback handles success/failure — no long-lived polling thread. The `active_` flag is set to false in the destructor to stop retries during shutdown. Combined with D97570592's push-based route invalidation, this completes the dev loop: Metro can start at any time, PackagerConnection auto-reconnects, HMR keeps the bundle fresh, and route changes propagate automatically. Changelog: [Internal] Reviewed By: christophpurrer Differential Revision: D97823787
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This pull request was successfully merged by @javache in 882be91 When will my fix make it into a release? | How to file a pick request? |
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This pull request has been merged in 882be91. |
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Summary:
When MWA starts before Metro is running, PackagerConnection's WebSocket connection to Metro's
/messageendpoint silently fails with no retry. The developer must restart MWA after starting Metro to get HMR working.This diff adds reconnection logic to PackagerConnection so it automatically retries when Metro becomes available. On initial connect failure or WebSocket disconnect, PackagerConnection schedules a retry after 5 seconds using the existing
WebSocketClientFactoryto create a fresh client. On successful reconnect, it firesliveReloadCallback_()which triggersFoxReactHost::reloadReactInstance()to load the bundle from Metro and set up HMR.The reconnection is event-driven: each retry is a short-lived thread that sleeps 5 seconds then calls
attemptConnection(). The connect callback handles success/failure — no long-lived polling thread. Theactive_flag is set to false in the destructor to stop retries during shutdown.Combined with D97570592's push-based route invalidation, this completes the dev loop: Metro can start at any time, PackagerConnection auto-reconnects, HMR keeps the bundle fresh, and route changes propagate automatically.
Changelog: [Internal]
Reviewed By: christophpurrer
Differential Revision: D97823787