First, of course, we need a convict itself:
let convict = require("convict")
Then, we can define our schema:
let configSchema = {
launchTime: {
doc: 'Time Convict was loaded',
format: 'string',
env: 'TIME'
},
port: {
doc: 'The port to bind.',
format: 'int',
default: 8080,
env: 'PORT',
providerPath: '/port'
}
};
Of course, `providerPath` isn't actually part of the `convict` schema! But it doesn't mind. This can be used for further processing in your `load()` function.
Now, we need to define our loader function. I usually call this a `provider`. It needs to return a JavaScript object that matches the keys in your `configSchema`, but the values can be dynamically generated. While you can pass this function the full `convict` object, I find it easier to deal with the schema itself:
let provider = function(configSchema){
// simulating an outside data source
let customKeyValueStore = {
'/port': 8000
}
let obj = {};
obj.launchTime = Date.now();
obj.port = customKeyValueStore[configSchema.port.providerPath]
return obj;
}
This function will return an object like this:
console.log(provider(configSchema))
Which we can then, finally, pass into `convict`:
let conf = convict(configSchema).load(provider(configSchema));
I usually statically return the parsed `convict` config using a call to getPropeties() and import it where I need it:
module.exports = conf.getProperties()
// in another module...
// let config = require('./config')
// console.log(config)
1 comment
- posted 5 years ago byNice idea with `provider`. I have several questions about your `configSchema` 1. Your `launchTime` parameter has `format: string` but you put a number there. May be it is better to change to `timestamp` to make it less confusing for newcomers 2. `launchTime` does not have `default` field - because of this `convict` processes this field wrong. You can see it at line 30 if you check `conf._schema.properties.launchTime` value - it does not contain schema definition
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