Netlify Functions with faunaDB-graphql backend returns a 502 in production only


Trying to get a normal Apollo GraphQL serverless backend working with netlify functions. But when I try to run my Query in production it just returns with a 502 error in production only. Works just fine in development.

github repo:

Any ideas? Thank you in advance.

log error: POST 502
netlify instance name:

Looks like a dependency is missing in the function

{"errorType":"Runtime.ImportModuleError","errorMessage":"Error: Cannot find module 'apollo-server-lambda'\nRequire stack:\n- /var/task/backend.js\n- /var/runtime/UserFunction.js\n- /var/runtime/index.js","trace":["Runtime.ImportModuleError: Error: Cannot find module 'apollo-server-lambda'","Require stack:","- /var/task/backend.js","- /var/runtime/UserFunction.js","- /var/runtime/index.js","    at _loadUserApp (/var/runtime/UserFunction.js:100:13)","    at Object.module.exports.load (/var/runtime/UserFunction.js:140:17)","    at Object.<anonymous> (/var/runtime/index.js:43:30)","    at Module._compile (internal/modules/cjs/loader.js:1158:30)","    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1178:10)","    at Module.load (internal/modules/cjs/loader.js:1002:32)","    at Function.Module._load (internal/modules/cjs/loader.js:901:14)","    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:74:12)","    at internal/main/run_main_module.js:18:47"]}

Which is odd because its here:

This is perplexing :thinking:

You say it works elsewhere?

Hi David,

Thanks for the quick response! Yes, the query works just fine in development with netlify dev , but returns the 502 error in production.

To reproduce the error check the console log when you visit

the Netlify functions folder backend was set up following the steps used in this tutorial: at around the 1:06:35 mark

It seems like the dependancies aren’t being installed in the functions folder.

Can you update your build command to: yarn build && cd functions/backend && npm install

Alternatively the should automatically install function dependancies for you and you won’t need to change your build command.

Totally worked! Thank you!

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