How to parse serverless.yml file in script - serverless-framework

Question

I need to read the serverless.yml config for use in some test mocks.
The following worked until a recent change:
const serverless = new Serverless()
await serverless.init()
const service = await serverless.variables.populateService()
How does one read the file now? There is an astounding lack of documentation in regards to using serverless progamically.

Answer 1

Well I ended up taking some code from the AppSync emulator package. I am not sure it covers it does a full parsing but it does the job for me.
import Serverless from 'serverless'
import path from 'path'
import fs from 'fs'
class ConfigServerless extends Serverless {
async getConfig(servicePath) {
this.processedInput = {
commands: [],
options: { stage: 'dev' }
}
this.config.servicePath = servicePath
this.pluginManager.setCliOptions(this.processedInput.options)
this.pluginManager.setCliCommands(this.processedInput.commands)
await this.service.load(this.processedInput)
this.pluginManager.validateCommand(this.processedInput.commands)
return this.variables
.populateService(this.pluginManager.cliOptions)
.then(() => {
this.service.mergeArrays()
this.service.setFunctionNames(this.processedInput.options)
this.service.validate()
})
}
}
const normalizeResources = config => {
if (!config.resources) {
return config.resources
}
if (!config.resources.Resources) {
return {}
}
if (!Array.isArray(config.resources.Resources)) {
return config.resources
}
const newResources = config.resources.Resources.reduce(
(sum, { Resources, Outputs = {} }) => ({
...sum,
...Resources,
Outputs: {
...(sum.Outputs || {}),
...Outputs
}
}),
{}
)
return {
Resources: newResources
}
}
export async function loadServerlessConfig(cwd = process.cwd()) {
const stat = fs.statSync(cwd)
if (!stat.isDirectory()) {
cwd = path.dirname(cwd)
}
const serverless = new ConfigServerless()
await serverless.getConfig(cwd)
const { service: config } = serverless
const { custom = {} } = config
const output = {
...config,
custom: {
...custom
},
resources: normalizeResources(config)
}
return output
}