Change default fetchPolicy to "cache-and-network"

[pcorey]

Hello,

I thought I'd open up this issue for discussion. The current fetchPolicy on GraphQL queries is "cache-first". This default assumes that all mutations are either made by, or can be predicted by the client. I would argue that this isn't true for most web applications.

Defaulting fetchPolicy to "cache-first" opens up the possibility of stale cache reads throughout an app if any queried data has been updated on the server (or by another client) without the client's knowledge. The only way to fix this is to go though your app and mark every query with a more appropriate fetchPolicy (like "cache-and-network").

I think a more sane default for fetchPolicy would be "cache-and-network". In my mind, this gives developers a more predictable experience. If a query result lives in cache, it will be returned while a network round trip takes place. If a developer knows that a query can only be affected by client-initiated changes (which I believe is a more rare use case), they can change their fetchPolicy to "cache-first" for performance gains.

Short of changing the fetchPolicy default value from "cache-first" to "cache-and-network", it might be worth considering making this default value configurable when initializing the Apollo client instance.

Any thoughts? Thanks!

• apollo-client@1.9.1

[sepehr500]

I think a default policy of network-only makes more sense. You don't want your application to be storing sensitive information without you specifically setting it to do so.

[vieiralucas]

+1 for allowing the default value to be configurable.

[pcorey]

This hasn't been discussed, and consensus hasn't been reached, but I thought I'd throw our a PR for posterity and discussion.

[jbaxleyiii]

@pcorey what do you think about a way to set defaults for all of the watchQueryOptions? Vue apollo does this and it could be useful for other integrations for it to be part of the core!

[pcorey]

@jbaxleyiii Something to consider, for sure.

I haven't dug deep enough to figure out the difference between ModifiableWatchQueryOptions vs the extended WatchQueryOptions, but does it make sense to want to have a global default for things like variables, query, and others?

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This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions to Apollo Client!

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This issue has been automatically closed because it has not had recent activity after being marked as stale. If you belive this issue is still a problem or should be reopened, please reopen it! Thank you for your contributions to Apollo Client!

[ceferrari]

+1

[7ynk3r]

any updates on this?

[josepjaume]

It'd be nice to have the default be configurable indeed!

[7ynk3r]

hello everyone, i found that it's possible to set it by default:

    const defaultOptions = {
      watchQuery: {
        fetchPolicy: 'cache-and-network',
        errorPolicy: 'all',
      },
      query: {
        fetchPolicy: 'cache-and-network',
        errorPolicy: 'all',
      },
      mutate: {
        errorPolicy: 'all',
      },
    };

    const client = new ApolloClient({
      link,
      cache,
      defaultOptions,
    });

for more: https://www.apollographql.com/docs/react/basics/setup.html#ApolloClient

[sajsanghvi]

I'm getting an error that says "cache-and-network" can only be used with WatchQuery .. anyone have any ideas for this?