[Feature Request] Ignore null arguments

[thanhbinh84]

Steps to reproduce:

1. Having a script to update profile such as:

mutation UpdateProfile ($birthday: String, $deviceToken: String)  {
    updateProfile(
        birthday: $birthday,
        deviceToken: $deviceToken
    )
}

2. Passing deviceToken value only

Expected
Generate graphql without birthday:

mutation {
    updateProfile(
        deviceToken: "abc"
    )
}

Actual
Generate graphql with null birthday:

mutation {
    updateProfile(
        deviceToken: "abc",
        birthday: null 
    )
}

Specs
Artemis version: ^6.0.4-beta.1

build.yaml:

targets:
  $default:
    sources:
      - lib/**
      - graphql/**
      - my.schema.graphql
    builders:
      artemis:
        options:
          fragments_glob: graphql/fragments/common.graphql
          schema_mapping:
            - schema: my.schema.graphql
              queries_glob: graphql/*.graphql
              output: lib/libs/graphql/graphql_api.dart
              naming_scheme: pathedWithFields

Artemis output:

# Please paste the output of
$ flutter pub run build_runner build --verbose
#or
$ pub run build_runner build --verbose

[INFO] Generating build script...
[INFO] Generating build script completed, took 415ms

[INFO] Creating build script snapshot......
[INFO] Creating build script snapshot... completed, took 12.1s

[WARNING] The package `adix` does not include some required sources in any of its targets (see their build.yaml file).
The missing sources are:
  - $package$
[INFO] Initializing inputs
[INFO] Building new asset graph...
[INFO] Building new asset graph completed, took 677ms

[INFO] Checking for unexpected pre-existing outputs....
[INFO] Deleting 3 declared outputs which already existed on disk.
[INFO] Checking for unexpected pre-existing outputs. completed, took 7ms

[INFO] Running build...
[INFO] Generating SDK summary...
[INFO] 4.3s elapsed, 1/17 actions completed.
[INFO] Generating SDK summary completed, took 3.7s

[INFO] 5.4s elapsed, 2/17 actions completed.
[INFO] 6.5s elapsed, 5/21 actions completed.
[INFO] 7.5s elapsed, 6/22 actions completed.
[INFO] 8.6s elapsed, 6/22 actions completed.
[INFO] 9.6s elapsed, 6/22 actions completed.
[INFO] 10.7s elapsed, 6/22 actions completed.
[INFO] 11.8s elapsed, 6/22 actions completed.
[INFO] 14.3s elapsed, 6/22 actions completed.
[INFO] 15.6s elapsed, 6/22 actions completed.
[INFO] 19.4s elapsed, 7/22 actions completed.
[INFO] 20.6s elapsed, 14/28 actions completed.
[INFO] 21.7s elapsed, 50/66 actions completed.
[INFO] 22.7s elapsed, 167/167 actions completed.
[INFO] Running build completed, took 22.8s

[INFO] Caching finalized dependency graph...
[INFO] Caching finalized dependency graph completed, took 81ms

[INFO] Succeeded after 22.8s with 4 outputs (172 actions)

GraphQL schema:

# If possible, please paste your GraphQL schema file,
# or a minimum reproducible schema of the bug.

GraphQL query:

# If possible, please paste your GraphQL query file,
# or a minimum reproducible query of the bug.

[vasilich6107]

Hi. Could you add a little bit reasoning behind this feature?

[thanhbinh84]

Hi. Could you add a little bit reasoning behind this feature?

There are two reasons:

1. In case profile has an attribute is in enum type, graphql will reject null value.
2. If we want to update only one field such as firstname only, it possibly empty other fields with null value

[vasilich6107]

Thanks.
I’ll check this with graphql faker.

[Grohden]

@thanhbinh84 @vasilich6107
about ignoring nulls, I've been using a flag for json serializable on build.yaml:

targets:
  $default:
    builders:
      # Some of our queries fail when we send null keys
      # (foo)
      json_serializable:
        options:
          include_if_null: false

Maybe this solves for you?

The downside is that it applies to your whole project, so if your backend relies on specifically receiving null vs undefined to create specific behavior, that will cause problems for you (oh well, only node will probably have undefined AND null to represent key absences...)

[comigor]

Hello there, how are you doing?
So, GraphQL spec accepts both null and the absence of the key as the same: https://spec.graphql.org/draft/#sel-GAFdRHABABsC0pB
And, as json_serializable have this option (as pointed by @Grohden), maybe we should avoid having this option on artemis?

[thanhbinh84]

Thanks for your info. @Grohden's solution works, we don't need to update our lib then.

Cheers.

[GP4cK]

@comigor @thanhbinh84 I don't think that solves the issue completely.
For example: let's say I have a user like this:

input User {
  id: String! 
  firstName: String
  lastName: String
  companyID: String
}

Now I want to update the firstName and remove them from a company, I would send a mutation like:

mutation updateUser {
  id: "myUserID"
  firstName: "Alice"
  # lastName is not included because I don't want to update it
  companyID: null
}

How can I do that?

[thanhbinh84]

@GP4cK I haven't tried but passing empty string "" might help, as json serializable will bypass null but keep empty string.

[GP4cK]

@GP4cK I haven't tried but passing empty string "" might help, as json serializable will bypass null but keep empty string.

Ok so then it will be the responsibility of the server to convert the empty string to null if it's a foreign key. That's a workaround.

[Grohden]

@GP4cK Just an idea: you could create a scalar (something like DbNull) use it with a union and deal with it differently on the server side
🤔
Not sure if artemis handles union types

Also, there's... a trick you could use

input User {
  id: String! 
  firstName: String
  lastName: String
  companyID: [String]
}

A list ([String]) would in some ways satisfy a Optional/Maybe idea:
if the list itself is null, then the value is not present (meaning undefined)
if the list is present but empty, then it means that the optional is empty (meaning null)
if the list is present and not empty, then it means it holds a value (meaning T)

Of course, this is a hack (which I may remember from list and maybe being monads (?)🤔) and probably will end up introducing more problems..

Anyway, I think that the only way to actually solve this is to have artemis processing a gql directive (maybe configurable on build.yaml) and then generating the json_serializable class with the include_if_null flag based on that directive