Can I inject certificates or other files into my app at build time?

No, App Platform does not currently support injecting values as files on disk. However, you can add the contents of a certificate or file as an environment variable and then save that value to disk using build or run time commands.

For example, MongoDB requires a Certificate Authority (CA) certificate for clients to connect to a cluster, and most MongoDB clients require the certificate to be a file on disk. You can work around the injection limitation by creating an environment variable, such as MONGO_CA_CERT=${db.CA_CERT}, during the app’s creation process or by updating its settings. Then, you can add a command to the app that creates the certificate file upon runtime, such as echo $MONGO_CA_CERT > ca_cert.cert && <original run command>. App Platform requires the original run time command to start the app upon runtime.