Load the correct logback file for the http json service respecting the deployment situation

[realvictorprm]

Prior it was not possible to enable json logging for the packaged daml sdk, because of a bug in how we reload the logback.xml for configuration changes. These changes now make use of an env var which exists for the case of being packaged with the daml sdk to retrieve the absolute path to the logback file and handing it over for the reload.

changelog_begin

[HTTP-JSON]

• fixed that json log output could not be enabled via cli options except via usage of env vars

changelog_end

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[realvictorprm]

So proof that with this fix it works correctly (just to track that this manual test succeeded):

$ daml json-api --ledger-host localhost --ledger-port 6865 --http-port 5634 --log-encoder json
{"@timestamp":"2021-06-09T12:28:55.325+02:00","@version":"1","message":"Config(ledgerHost=localhost, ledgerPort=6865, address=127.0.0.1, httpPort=5634, portFile=None, packageReloadInterval=5 seconds, packageMaxInboundMessageSize=None, maxInboundMessageSize=4194304, tlsConfig=TlsConfiguration(false,None,None,None,REQUIRE,false,List()), jdbcConfig=None, staticContentConfig=None, allowNonHttps=false, accessTokenFile=None, wsConfig=None, nonRepudiationCertificateFile=None, nonRepudiationPrivateKeyFile=None, nonRepudiationPrivateKeyAlgorithm=None)","logger_name":"com.daml.http.Main","thread_name":"main","level":"INFO","level_value":20000,"instance_uuid":"008a3483-cac2-491f-bf1a-6958a9fd89bb"}
{"@timestamp":"2021-06-09T12:28:55.557+02:00","@version":"1","message":"Slf4jLogger started","logger_name":"akka.event.slf4j.Slf4jLogger","thread_name":"http-json-ledger-api-akka.actor.default-dispatcher-4","level":"INFO","level_value":20000}
{"@timestamp":"2021-06-09T12:28:55.718+02:00","@version":"1","message":"HTTP Server pre-startup","logger_name":"com.daml.http.HttpService","thread_name":"http-json-ledger-api-akka.actor.default-dispatcher-8","level":"INFO","level_value":20000,"instance_uuid":"008a3483-cac2-491f-bf1a-6958a9fd89bb"}
{"@timestamp":"2021-06-09T12:28:55.950+02:00","@version":"1","message":"Attempting to connect to the ledger localhost:6865\n (attempt 1/600)","logger_name":"com.daml.http.LedgerClient$","thread_name":"http-json-ledger-api-akka.actor.default-dispatcher-8","level":"INFO","level_value":20000}
{"@timestamp":"2021-06-09T12:28:57.579+02:00","@version":"1","message":"Attempting to connect to the ledger localhost:6865\n (attempt 2/600)","logger_name":"com.daml.http.LedgerClient$","thread_name":"timer-utils","level":"INFO","level_value":20000}
{"@timestamp":"2021-06-09T12:28:58.587+02:00","@version":"1","message":"Attempting to connect to the ledger localhost:6865\n (attempt 3/600)","logger_name":"com.daml.http.LedgerClient$","thread_name":"timer-utils","level":"INFO","level_value":20000}
{"@timestamp":"2021-06-09T12:28:59.597+02:00","@version":"1","message":"Attempting to connect to the ledger localhost:6865\n (attempt 4/600)","logger_name":"com.daml.http.LedgerClient$","thread_name":"timer-utils","level":"INFO","level_value":20000}
^C{"@timestamp":"2021-06-09T12:28:59.886+02:00","@version":"1","message":"Stopping server...","logger_name":"com.daml.http.HttpService","thread_name":"shutdownHook1","level":"INFO","level_value":20000,"instance_uuid":"008a3483-cac2-491f-bf1a-6958a9fd89bb"}

[cocreature]

The fact that you only do this in the JSON API seems a bit worrying. We handle logback files the same for all components. Should we move the logic into reconfigure?

[realvictorprm]

That was my thought too, but so far I see only the json api does this because no other service spits out json logs yet if I remember correctly.

Considering that the system prop is named same for every other service I think this should be safe to move there 🤔

[cocreature]

I’m hoping that the fact that no other sevrice supports this is a temporary state and eventually everything produces json logs :)

[realvictorprm]

ok adressed with e795cfc

fine for you @cocreature ?

[cocreature]

lgtm with one suggestion