Airbyte Mutatable Spec

connector.js

getSpec() {
  // start the returned spec with constant properties that are always needed in all ways the connector can be deployed
  let spec = {
     properties: {
      host: { required:true, type: string },
      username: { required:true, type: string },
      password: { required:true, type: string },
     }
  };
  
  // if the platform has not set S3_URL for this connector, we need to ask the user for it, otherwise this is excluded from the spec
  if (!process.env.S3_URL) {
    spec.properties.s3_url = { required:true, type: string }
  }
  
  return spec
}

read (config, configuredCatalog, ...) {
  // when the connector runs, we source the ENV again to pre-fill any properties we get from the ENV and not the config
  if (!config.properties.s3_url && process.env.S3_URL) {
    config.properties.s3_url = process.env.S3_URL
  }
}

// Notes:
// All of the above can be simplified and done dynamically with helpers like:

function stripConfigOfEnvs (config) {
  for (const [key,value] in process.env){
    if (key.startsWith(`AIRBYTE_CONNECTOR_${connector_name}_`)){
      //...
      delete config.properties.key_name
    }
  }
}

function addEnvConfigsBackToConfig (config) {
  //... 
}