(graphcache) - Expose data on write and writeOptimistic results

[kitten]

This is potentially a missing piece to use Graphcache to fully simulate a schema.
When simulating queries, they can be written using write and queried using query.

To simulate mutations we currently only have writeOptimistic + opts.optimistic + opts.updates to generate a mutation result from scratch. To get around this one would need the writeOptimistic result.

This can then be enriched, e.g.:

import { createRequest } from '@urql/core';
import { writeOptimistic, query, write } from '@urql/exchange-graphcache';

const store = new Store(/* ... */);

/** This would fully simulate a mutation using optimistic updates, queries so that resolvers can update the data, then writes it back permanently, assuming that the resolvers return serialisable data. */
const mutation = (query, variables) => {
  const request = createRequest(query, variables);
  const result = writeOptimistic(store, request, request.key);
  result.data = query(store, request, result.data).data;
  result.data = write(store, request, result.data).data;
  return result;
};

[changeset-bot]

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Name	Type
@urql/exchange-graphcache	Patch

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