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Running backend server using SeaLights agent and preload.js

In order to To run your backend service with Sealights without changing the startup command, you can use the preload.js file and the NODE_OPTIONS environment variable
. This is a common practice in docker containers where the ENTRYPOINT cannot be modified.

• The agent contains a preload.js file under node_modules/slnodejs/lib/preload.js

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• . You use it by setting the environment variable: NODE_OPTIONS="--require ./node_modules/slnodejs/lib/preload.js"

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• In the current working directory, the agent will search for the token in the file sltoken.txt and the build session

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• ID in the file buildSessionId.

• Other parameters can be passed to

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• the agent using the following syntax: SL_ + {command line flag}

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• . For instance,

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• to pass the lab ID, you can set SL_labId=my_lab_id

Sample docker file:

ENV SL_labId=integ_test_otel
ENV NODE_OPTIONS="--require ./node_modules/slnodejs/lib/preload.js"

ENTRYPOINT [ "node", "--require", "./tracing.js", "index.js" ]