[interop] Array default with transfrom

[hasezoey]

mongoose version: 5.6.6(NPM)
nodejs: 12.7.0

reproduce script:

import * as mongoose from "mongoose";

const testSchema = new mongoose.Schema({
    testArray: [{ default: ["testDefault"], type: String, lowercase: true }]
});

const testModel = mongoose.model("test", testSchema);

(async () => {
    mongoose.set("debug", true);
    await mongoose.connect(`mongodb://mongodb:27017/`, {
        useNewUrlParser: true,
        useFindAndModify: true,
        useCreateIndex: true,
        dbName: "verify",
        user: "user",
        pass: "passwd",
        authSource: "admin",
        autoIndex: true
    });

    const doc = new testModel({});
    await doc.save();
    console.log(doc.toObject());

    await mongoose.disconnect();
})();

log

Mongoose: tests.insertOne({ testArray: [], _id: ObjectId("5d38883c65478f080346dfad"), __v: 0 }, { session: null })
{ testArray: [], _id: 5d38883c65478f080346dfad, __v: 0 }

current behavior: dosnt apply the default value when formatted so / has a "string" transform
wanted behavior: applys default value when formatted so

PS: i make this a question, because i dont know if this is an actual bug
and if there is actually an other issue having this problem, i didnt find it...

[vkarpov15]

Going to postpone this until 5.7.0 because I think this is a bit too risky for a patch release.

[hasezoey]

@vkarpov15 after testing it in mongoose@5.7.0 the initial example i gave, dosnt work, but others do

works:

import * as mongoose from "mongoose";

const testSchema = new mongoose.Schema({
  testArray: [{ type: String, lowercase: true }]
});

const testModel = mongoose.model("test", testSchema);

(async () => {
  mongoose.set("debug", true);
  await mongoose.connect(`mongodb://localhost:27017/verify`, {
    useNewUrlParser: true,
    useFindAndModify: true,
    useCreateIndex: true,
    autoIndex: true
  });

  const doc = await testModel.create({ testArray: ["MAKE ME LOWERCASE"] });
  console.log(doc.toObject());

  await mongoose.disconnect();
})();

// result:
// {"testArray":["make me lowercase"],"_id":"5d772503932ef4351940bff4","__v":0}

dosnt work:

import * as mongoose from "mongoose";

const testSchema = new mongoose.Schema({
  testArray: [{ default: ["testDefault"], type: String, lowercase: true }]
});

const testModel = mongoose.model("test", testSchema);

(async () => {
  mongoose.set("debug", true);
  await mongoose.connect(`mongodb://localhost:27017/verify`, {
    useNewUrlParser: true,
    useFindAndModify: true,
    useCreateIndex: true,
    autoIndex: true
  });

  const doc = await testModel.create({});
  console.log(doc.toObject());

  await mongoose.disconnect();
})();
// result:
// { testArray: [], _id: 5d77249e9341eb34490df597, __v: 0 }

so my assumption is that default dosnt get applied to arrays when defined so

PS: sorry for not testing it earlier

[vkarpov15]

@hasezoey that's because you're defining the default on the individual array values, not on the array as a whole. If you define your schema as shown below, it works fine.

const testSchema = new mongoose.Schema({
  testArray: {
    type: [{ type: String, lowercase: true }],
    default: ["testDefault"]
  }
});

[hasezoey]

Thanks for implementing it and for the documentation, but now where i try to implement it, i got some question on how to use it, because:

• mongoose.Schema.Types.String.prototype.OptionsConstructor instanceof mongoose.SchemaTypeOptions returns false
• and (example) trim dosnt exists on mongoose.Schema.Types.String.prototype.OptionsConstructor

what i more fully mean:

// "Type" can be something like "mongoose.Types.String"
// logger is npm package "log-level"
const returnObject = {
  type: [{
    type: Type
  }]
};

// @ts-ignore
if (Type.prototype.OptionsConstructor instanceof mongoose.SchemaTypeOptions) { // returns false
  for (const [key, value] of Object.entries(options)) {
    if (key in Type.prototype.OptionsConstructor) { // when disabling the "returns false" check above, this always takes the else route
      logger.debug('Value is in OC:', key);
      returnObject.type[0][key] = value;
    } else {
      logger.debug('Value is not in OC:', key);
      returnObject[key] = value;
    }
  }

  logger.debug('final obj', returnObject);
}

am i just using it wrong? @vkarpov15

---

and from the documentation schema.path('name').options instanceof mongoose.SchemaTypeOptions; // true i cant use, because this is needed before a schema creation

---

update:
is mongoose.Schema.Types.String.prototype.OptionsConstructor.prototype the only option to get the settings? because this way, it only includes the options of "String" and not the ones from "SchemaTypeOptions" (like required is not present)

---

node: 12.11.1
mongoose: 5.7.5
typescript: 3.6.3

[vkarpov15]

mongoose.Schema.Types.String.prototype.OptionsConstructor is the constructor used to instantiate options, not an instance of options. For example, you'll see mongoose.Schema.Types.Boolean.prototype.OptionsConstructor === mongoose.SchemaTypeOptions. And, similarly:

> Object.getOwnPropertyDescriptor(mongoose.Schema.Types.String.prototype.OptionsConstructor.prototype, 'trim')
{ value: null,
  writable: true,
  enumerable: true,
  configurable: true }
> 
> Object.getOwnPropertyNames(mongoose.Schema.Types.String.prototype.OptionsConstructor.prototype)
[ 'constructor', 'enum', 'match', 'lowercase', 'trim', 'uppercase' ]
> 

Sorry for the long stream of dots and prototypes. Might be easier to just export mongoose.SchemaStringOptions so you can do Object.getOwnPropertyNames(mongoose.SchemaStringOptions.prototype)

[hasezoey]

Sorry for the long stream of dots and prototypes. Might be easier to just export

im fine with it, as long as it is consistent

---

For example, you'll see mongoose.Schema.Types.Boolean.prototype.OptionsConstructor === mongoose.SchemaTypeOptions = true

but mongoose.Schema.Types.String.prototype.OptionsConstructor === mongoose.SchemaTypeOptions = false

-> it seems like Schema.Types.Boolean does not have an entry in lib/options, just wanted to share that, might be right so or forgotten, i dont know

---

it seems the type Schema.Types.String is missing some options, like maxlength, minlength @vkarpov15

Update: i made an new issue for this

---

Thanks for this, it made the typegoose code more understandable & maintainable instead of having to redefine the options when mongoose updates :)

[vkarpov15]

No but mongoose.Schema.Types.String.prototype.OptionsConstructor is a class that inherits from mongoose.SchemaTypeOption.