Handle read-only config file gracefully in Docker Swarm#157
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updateConfigFile() calls fs.writeFile on the config JSON file after updating the in-memory config via config.set(). In Docker Swarm, config files are mounted read-only, so the write fails and throw err crashes the entire process. Change to: - Keep config.set() for in-memory state (always works) - Log a warning instead of crashing if fs.writeFile fails - Also handle the case where require(configFile) fails The in-memory config remains correct for the duration of the process. On restart, the config file is re-read from the Docker config mount, so values like lastFHIR2ESSync will reset — but this is expected behavior in immutable infrastructure. Fixes intrahealth#139
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Problem
In Docker Swarm, config files are mounted as read-only Docker configs. When
updateConfigFile()ingeneralMixin.jstries to write back to the config file (e.g., to updatesync.lastFHIR2ESSyncafter an ES re-index),fs.writeFilefails andthrow erron line 53 crashes the entire process.This affects any deployment using Docker Swarm or Kubernetes where config files are immutable.
Fix
config.set()still updates the in-memory config (always works, keeps runtime state correct)fs.writeFilefailure now logs a warning instead of crashingrequire(configFile)failure is also handled (in case the file is inaccessible)The in-memory config remains correct for the duration of the process. On restart, the mounted config file is re-read — so values like
lastFHIR2ESSyncwill reset to whatever is in the Docker config, which means the next startup will do a full ES re-sync from that timestamp. This is expected behavior in immutable infrastructure.Fixes #139