Questions regarding localCacheMutations in 1.0 iOS client

Help
, ,
1

I’m learning to use LocalCacheMutations and @apollo_client_ios_localCacheMutation and would like feedback if I’m using the concepts properly.

If I’m trying to “build” some Data model, the initialization is a bit cumbersome. Imagine this example:

query collectionsLocalCacheMutation @apollo_client_ios_localCacheMutation {
    collections {
        edges {
            node {
                id
                name
            }
        }
    }
}

Then if we want to directly add a new edge/node there would be code as follows

    func addEdge(data: inout CollectionsLocalCacheMutation.Data) {
        var items = data.collections?.edges ?? []
                
        var newEdge = CollectionsLocalCacheMutation.Data.Collections.Edge(data: DataDict([:], variables: nil))
        newEdge.node = CollectionsLocalCacheMutation.Data.Collections.Edge.Node(data: DataDict([:], variables: nil))
        newEdge.node.id = "100"
        newEdge.node.name = "Sally"
        
        items.append(newEdge)
        data.collections?.edges = items
    }

Creating those empty DataDicts is annoying. This can be solved by adding an extension on the local cache mutation. Perhaps such a initializer belongs in the classes proper (as they are mutable)?

extension CollectionsLocalCacheMutation.Data.Collections.Edge {    
    init() {
        self.init(data: DataDict([:], variables: nil))
    }
}

The 0.51 code was a bit “safer” in my opinion. The above, while type-safe, doesn’t ensure that all the expected fields are set (node,id, node.name, etc). The equivalent code in 0.51 looked like:

        let newEdge = GetCollectionsQuery.Data.Collections.Edge(
            id: collection.id,
            node: GetCollectionsQuery.Data.Collections.Edge.Node(
                id: collection.id,
                name: collection.name
            )
        )

The signatures of the initializers forced one to set all the expected properties. And if the query ever changed (adding/removing fields) the above wouldn’t compile… leading you right to where code needed to be updated. The 1.0 pattern misses out of these features (unless I’m missing something).