Support for Enum

[LarsLiden]

Is there a way to support enum?

https://www.typescriptlang.org/docs/handbook/enums.html

[abobwhite]

If your enum is a string enum, this will work out-of-the-box without any clazz. I just verified.

[evergreen-lee-campbell]

Using a string enum works for serializing, but not deserializing.

[cantide5ga]

Isn't this a limitation of Typescript string enums? An enum would come in as a string request but cannot be reverse mapped to its member.

[evergreen-lee-campbell]

If I specify that it should be mapped to my enum's clazz, I'd like to be able to reverse map to the member (as you might with, say, the EnumMember decoration in C#).

[abobwhite]

Maybe try https://github.com/typestack/class-transformer. I prefer that solution to this one anyway, however, I haven't yet tried enums with it

[cantide5ga]

I think it's important to repeat that Typescript itself cannot reverse map an enum based on a string.

One workaround my colleague @imperialyoyo implemented was through a converter:

export const getEnumConverter = (stringEnum: StringEnum, name: string): ICustomConverter => {
    return {
        fromJson(data) {
            if (isArrayOrArrayClass(data)) {
                return (data as string[])
                    .map((dataElement) => getEnumMatch(stringEnum, dataElement, name));
            } else {
                return getEnumMatch(stringEnum, data, name);
            }
        },
        toJson(data) {
            if (isArrayOrArrayClass(data)) {
                return (data as string[]).map((dataElement) => dataElement.toString());
            } else {
                return data ? data.toString() : null;
            }
        }
    };
};

const getEnumMatch = (stringEnum: StringEnum, data: string, name: string) => {
    if (data == null) {
        return null;
    }
    if (stringEnum[data]) {
        return stringEnum[data];
    }
    const enumValueMatch = getEnumValueMatch(stringEnum, data);
    if (enumValueMatch) {
        return enumValueMatch;
    }
    return data;
};

const getEnumValueMatch = (stringEnum: StringEnum, data: string): string => {
    const enumPropertyNames = Object.getOwnPropertyNames(stringEnum);
    const foundReverseSearch = enumPropertyNames.map((property) => stringEnum[property]).indexOf(data);
    if (foundReverseSearch > -1) {
        return stringEnum[enumPropertyNames[foundReverseSearch]];
    } else {
        return null;
    }
};