[Bug] Using custom sync server does not work (server returns 404)

Steps to reproduce

Deploy your own sync server (uising docker: mozilla/syncserver:latest) behind an nginx reverse proxy with ssl). Turn on sync on firefox desktop 81.0 works fine (setting identity.sync.tokenserver.uri = https://subdomain.domain.tld/token/1.0/sync/1.5 and using default firefox accounts server). Using the same settings in firefox android 81.1.1 (setting user-defined sync server to https://subdomain.domain.tld/token/1.0/sync/1.5) fails, firefox android shows “last sync: Jan, 1st, 1970”. Debug message of self hosted syncserver shows:

INFO:mozsvc.metrics:{"code": 404, "request_time": 0.002107858657836914, "remoteAddressChain": ["141.*.*.*", "172.*.*.*"], "agent": "MozacFetch/57.0.6", "path": "https://subdomain.domain.tld/1.0/sync/1.5", "method": "GET"}

Considering the log message, it seems as if firefox android is using the wrong server url - the ‘token’ part is stripped off.

Expected behavior

Firefox android should sync with self-hosted syncserver.

Actual behavior

Sync fails.

Device information

• Android device: Nokia 7.1, Android 10
• Fenix version: 81.1.1(Build #2015764547)

┆Issue is synchronized with this Jira Task

[tslpre]

Tested another workaround (which doesn’t need to touch the web sever): just add a “/token” to the custom address - e.g. https://server/token/token/1.0/sync/1.5

That works…

[stale[bot]]

See: https://github.com/mozilla-mobile/fenix/issues/17373 This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.