Typescript does not compile with gateway 0.x and Apollo Server v2

[smyrick]

If you use gateway version 0.29.0+ with Apollo Server v2 you will start relying on apollo-server-types both ^0.9.0 OR ^3.0.0. See code

[email protected] -> AS2
[email protected] -> AS3

federation/gateway-js/package.json

Line 41 in 7f5565a

"apollo-server-types": "^0.9.0 || ^3.0.0",

Normally in dependencies, this would be ok, that we can use either version, however, the underlying dependency apollo-server-env also has a major version change. We updated the GraphQLRequest.headers to instead defined in apollo-server-env to be the Headers from node-fetch. This was an unintentional "breaking change" that got populated. It appears to have no effect on the runtime of most users but what it does break is Typescript compile steps. So if users have a tsc step they can't even use these versions together.

A potential fix is to instead have npm pull in the dependency of one or the other, we pull in both libs and define in the typed source code that the types themselves could be one or the other.

I believe we should also apply this fix to main if we want @apollo/gateway v2 to still work with AS2.

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After this large refactoring, it will require more work to re-apply my initial PR: #2050

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Initial PR to solve that now needs to be rewritten: #1964

Reproducible Stackblitz: https://stackblitz.com/edit/apolloserver-2-with-gateway-45?file=README.md

[glasser]

I think two small fixes will fix this:

• Backport apollographql/apollo-server@191d427 to AS2 and put out a quick apollo-server-env release
• Tweak overallCachePolicy in @apollo/server-gateway-interface to explicitly support either AS2 or AS3 versions (which actually simplifies the relevant code in @apollo/gateway)

[smyrick]

This has now been resolved with the following versions:

"@apollo/gateway": "0.52.1",
"apollo-server": "2.26.0"

OR if you have a hard set dependency on apollo-server-types

"@apollo/gateway": "0.52.1",
"apollo-server": "2.26.0",
"apollo-server-types": "0.10.0"

See the linked issues above for more details.