This PR addresses a bug described in #263
Basically, whenever a struct involves a custom genqlient binding, a
secondary "premarshal" struct gets generated.
The bug was that this "premarshal" struct was not propagating the
`omitempty` JSON tags, which was resulting in unexpected behavior.
The fix involved a few changed lines in the Go template, and a few
changes in the unit tests.
I have:
- [x] Written a clear PR title and description (above)
- [x] Signed the [Khan Academy CLA](https://www.khanacademy.org/r/cla)
- [x] Added tests covering my changes, if applicable
- [x] Included a link to the issue fixed, if applicable
- [x] Included documentation, for new features (n/a)
- [x] Added an entry to the changelog
This allows client code to see the operation (query or mutation) exactly
as genqlient sends it over the wire. This data was already available in
the generated safelist.json file, but now it's easily available from Go
code as well.
Fixes#236
I have:
- [x] Written a clear PR title and description (above)
- [x] Signed the [Khan Academy CLA](https://www.khanacademy.org/r/cla)
- [x] Added tests covering my changes, if applicable
- [x] Included a link to the issue fixed, if applicable
- [x] Included documentation, for new features
- [x] Added an entry to the changelog
This enables accessing the Extensions field, as defined in the response
format: https://spec.graphql.org/October2021/#sec-Response-Format
Extensions can be enabled using configuration option use_extensions.
This will change the return parameters of the generated client
functions. Making it a breaking change if enabled.
Since extensions are untyped as defined in the spec, the Client will
return an interface of type map[string]interface{}.
`Code generated by` disclaimer should be at the top of the file, as it is demonstrated in [this article](https://go.dev/blog/generate) on The Go Blog.
The current placing breaks integration with some code formatters and linters which do no skip files generated by `genqlient`.
## Summary:
If your type implements an interface, we add getter methods for the
shared fields, so that those may be accessed via the interface. But it
turns out occasionally it's useful to have these getter methods when
they don't implement a GraphQL interface, so you can use two
genqlient-generated types in the same function if they have the same
fields. (This comes up most often when you have a GraphQL union that
maybe should really be an interface, or if you don't yet support
interfaces implementing other interfaces (indeed our parser doesn't
either). But one can imagine other use cases.)
We can't predict how you want to do that, so we can't generate the
interface, but we can generate the methods, so you can define the
interface and do a type assertion from there. Since these methods are
pretty simple to generate, we just do it always. (As with #120, if
binary size becomes an issue we could later add an option to only
generate methods that are truly needed but including them seems like the
better default.)
This also fixes a subtle and rare bug, which would have become much more
common (indeed existing tests caught it). Specifically, if you have a
query like
```graphql
fragment FragmentOne on T { id }
fragment FragmentTwo on T { id }
query Q {
f { # interface type T
...FragmentOne
...FragmentTwo
}
}
```
since both `FragmentOne` and `FragmentTwo` request some common field,
say `id`, we generate a method `GetId` on each one. But since
`FragmentOne` and `FragmentTwo` are both on `T`, we also include their
interfaces in the interface we generate for the type of `f`, `QFT`. So
`QFT` includes a method `GetId`. But on the implementations, the two
methods conflict, and neither gets promoted; this causes various code to
fail to compile. With this change, this would have happened much more
frequently -- even if only one of the two fragments is on `T`, as long
as both request the field. Anyway, we now generate explicit methods on
each struct for all of its recursively emebedded fields -- using the
logic from #120 to compute them -- so that we don't need to rely on
method-promotion.
## Test plan:
make tesc
Author: benjaminjkraft
Reviewers: csilvers, dnerdy, aberkan, jvoll, mahtabsabet, MiguelCastillo, StevenACoffman
Required Reviewers:
Approved By: csilvers, dnerdy
Checks: ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Lint, ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Lint
Pull Request URL: https://github.com/Khan/genqlient/pull/126
## Summary:
This has been a bit of a thorn since we started using genqlient in
production: just as you might want to specify, say, `omitempty` on an
argument, you might equally want to specify it on an input-type field.
But there's no obvious syntax to do that, because the input-type field
does not appear in the query (only the schema) so there's nowhere to put
the `# @genqlient` directive.
This commit, at last, fixes that problem, via a new option, `for`, which
you use in an option applied to the entire operation (or fragment), and
says, "actually, apply this directive to the given field, not the entire
operation". (It's mainly useful for input types, but I allowed it for
output types too; I could imagine it being convenient if you want to say
you always use a certain type or type-name for a certain field.) It
works basically like you expect: the inline options take precedence over
`for` take precedence over query-global options.
The implementation was fairly straightforward once I did a little
refactoring, mostly in the directive-parsing and directive-merging
(which are now combined, since merging is now a bit more complicated).
With that in place, and extended to support `for`, we need only add the
same wiring to input-fields that we have for other places you can put
directives. I did not attempt to solve the issue I've now documented
as #123, wherein conflicting options can lead to confusing behavior;
the new `for` is a new and perhaps more attractive avenue to cause it
but the issue remains the same and requires nontrivial refactoring
(described in the issue) to solve. (The breakage isn't horrible for the
most part; the option will just apply, or not apply, where you don't
expect it to.)
But while applying that logic, I noticed a problem, which is that we
were inconsistently cascading operation-level options down to
input-object fields. (I think this came out of the fact that initially
I thought to cascade them, then realized that this could cause problems
like #123 and intended to walk them back, but then accidentally only
"fixed" it for `omitempty`. I guess until this change, operation-level
options were rare enough, and input-field options messy enough, that no
one noticed.) So in this commit I bring things back into consistency,
by saying that they do cascade: with at least a sketch of a path forward
to solve #123 via better validation, I think that's by far the clearest
behavior.
Issue: https://github.com/Khan/genqlient/issues/14
## Test plan:
make check
Author: benjaminjkraft
Reviewers: csilvers, StevenACoffman, benjaminjkraft, aberkan, dnerdy, jvoll, mahtabsabet, MiguelCastillo
Required Reviewers:
Approved By: csilvers, StevenACoffman
Checks: ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Lint, ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Lint
Pull Request URL: https://github.com/Khan/genqlient/pull/124
## Summary:
When genqlient generates output types, it generates whatever code is
necessary to unmarshal them. Conversely, when it generates input types,
it generates whatever code is necessary to marshal. This is all that's
needed for genqlient itself: it never needs to marshal output types or
unmarshal input types.
But maybe you do! (For example, to put the responses in a cache, which
is the use case that @csilvers hit at Khan, although there are others
one can imagine.) While we can't support every serialization format you
might want (at least not without adding plugins or some such), it's not
unreasonable to expect that since genqlient can read JSON, it can write
it too. Sadly, in the past this was not true for types requiring custom
unmarshaling logic, for several reasons.
In this commit I implement logic to always write both marshalers and
unmarshalers whenever they're needed to be able to correctly round-trip
the types, even though genqlient doesn't do so. I wasn't starting from
scratch, since of course we already write both marshalers and
unmarshalers in some cases. But this ended up requiring surprisingly
large changes on the marshaling side, mostly to correctly support
embedding (which we use for named fragments).
Specifically, as the comments in `types.go` discuss, the most difficult
issue is spreads with duplicate fields, which translate to Go embedded
fields which end up hidden from the json-marshaler. Ultimately, I had
to do things quite differently from unmarshaling, and essentially
flatten the type when we write marshaler. But in the end it's not so
ugly -- indeed arguably it's cleaner! Mainly it's just different.
One thing to note is that we do marshal `__typename` based on
what we know about the types; users need not fill it in (and if they
do we'll ignore it). This seemed to me to be a better UX, and
didn't add much complexity.
In general, I begin to wonder whether using `encoding/json` at all is
really right for genqlient: we're doing a lot of work to appease it,
despite knowing what our types look like. I think it would still be a
significant increase in lines of code to roll our own, but that code
would perhaps be simpler, and would surely be faster (although if we
just want the speed gains we could use another JSON-generator library,
see also #47). Anyway, something to think about in the future.
## Test plan:
make tesc
Author: benjaminjkraft
Reviewers: csilvers, StevenACoffman, benjaminjkraft, dnerdy, aberkan, jvoll, mahtabsabet, MiguelCastillo
Required Reviewers:
Approved By: StevenACoffman, dnerdy
Checks: ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Lint, ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Lint
Pull Request URL: https://github.com/Khan/genqlient/pull/120
## Summary:
There were a few bugs here, one of which Craig came across when pulling
the custom-unmarshaler change into webapp:
1. If you have an optional field with a custom unmarshaler, and the
server omits the field from the response entirely (i.e. does not
write `"myField": null`), we would still call your unmarshaler with
an input of `[]byte(nil)`. This is just wrong; it's our job to do
the nil-check. (This is the one Craig found; in practice gqlgen
servers do not do this and I think the spec says not to although it's
a bit fuzzy on the matter of serialization. But in practice we have
mocks that do it -- for required fields even! -- and it seems better
to handle it than pass you data on which you'll probably err or even
panic.)
2. If you have an optional field with a custom unmarshaler, and the
server returns an explicit null (i.e. `"myField": null`), we would
call your unmarshaler with `[]byte("null")`. In principle the intent
was you're supposed to implement that, as [`json.Unmarshaler`
advises][1]. But (a) I forgot to document that, and (b) in practice
`json.Unmarshal` [does *not* call you in that case][2], i.e. its
advice is unnecessary. So I think it's better for us to just match
it, and not call you. (And in that case I see no reason to bother
documenting the advice.)
3. If you have an optional, `pointer: true` field with a custom
marshaler, the reverse of (2) applies: if the pointer is nil, we
shouldn't really call you. (Indeed if you were a real
`json.Marshaler` with a value-method rather than a pointer-method,
trying to call you might panic!) Note we don't need to explicitly
write "null"; we just leave the `json.RawMessage` as nil, and
`json.Marshal` [handles that][3].
4. We handle interface types effectively the same as custom
unmarshalers, just we generate the unmarshaler. So if you have an
optional field with interface type, (1) would also apply there; our
generated unmarshaler returns an error in this case.
5. While (2) doesn't apply to such optional interface fields (because we
do the customary `if string(b) == "null"` check -- this I at least
thought to test), if you set `pointer: true` on the field, we would
still call the unmarshaler on the value, and it would no-op, but only
*after* we initialized the pointer. Put more simply, we'd return a
non-nil pointer to nil interface, rather than a nil pointer; this is
wrong since the whole point of `pointer: true` is you only get a
non-nil pointer if your value is nil! Of course, in practice there's
little reason to use `pointer: true` on interface fields, and indeed
this stuff gets so confusing my test was even wrong.
In this commit I fix all the bugs, by adding appropriate nil-checks to
wrap the unmarshaler-calls. The templates are, as always, a bit
confusing, but the generated code makes it clear what changed.
Note we'll want to land this before cutting a release with custom
marshaler/unmarshaler support, because the first three bugs are
potentially quite noticeable. (The latter two are in `v0.1.0`, but
presumably quite rare.)
[1]: https://pkg.go.dev/encoding/json#Unmarshaler
[2]: https://play.golang.org/p/Pw6zNN8trGO
[3]: https://play.golang.org/p/crTfnT7ePte
Issue: https://phabricator.khanacademy.org/D74453#inline-558571
## Test plan:
make tesc
Author: benjaminjkraft
Reviewers: csilvers, StevenACoffman, benjaminjkraft, aberkan, dnerdy, jvoll, mahtabsabet, MiguelCastillo
Required Reviewers:
Approved By: csilvers, StevenACoffman
Checks: ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Lint, ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Lint
Pull Request URL: https://github.com/Khan/genqlient/pull/116
🖍 _This is an audit!_ 🖍
## Summary:
This is what I get for not waiting for them to pass at each step of
landing a stack!
## Test plan:
make check
Author: benjaminjkraft
Auditors: dnerdy
Required Reviewers:
Approved By:
Checks: ⌛ Test (1.17), ⌛ Test (1.16), ⌛ Test (1.15), ⌛ Test (1.14), ⌛ Lint, ⌛ Lint, ⌛ Test (1.17), ⌛ Test (1.16), ⌛ Test (1.15), ⌛ Test (1.14)
Pull Request URL: https://github.com/Khan/genqlient/pull/112
## Summary:
Previously, we actually allowed you to put several genqlient directives
on the same node, but the semantics were undocumented (and somewhat
confusing, when it comes to `typename`). In order to support directives
on input options, we're actually going to be encouraging this usage (see
notes in #14), so it's time to fix it. To avoid confusion, I just had
conflicting directives be an error, rather than defining which one
"wins". The same applies to specifying the same option several
times in one directive.
I also fixed two small bugs:
- `typename` on an operation would incorrectly cascade down to
all input types in a query (causing conflicts).
- directive parse errors had useless positions, now they're correct
## Test plan:
make check
Author: benjaminjkraft
Reviewers: StevenACoffman, dnerdy, aberkan, jvoll, mahtabsabet, MiguelCastillo
Required Reviewers:
Approved By: StevenACoffman, dnerdy
Checks: ⌛ Test (1.17), ⌛ Test (1.16), ⌛ Test (1.15), ⌛ Test (1.14), ⌛ Lint, ⌛ Test (1.17), ⌛ Test (1.16), ⌛ Test (1.15), ⌛ Test (1.14), ⌛ Lint
Pull Request URL: https://github.com/Khan/genqlient/pull/105