## Summary:
In previous commits I added support to genqlient for interfaces,
inline fragments, and, most recently, named fragments of concrete
(object) type. This leaves only named fragments of interface type!
Like other named fragments, these are useful for code-sharing,
especially if you want some code that can handle the same fields of
several different types.
As seems to be inevitable with genqlient, this was mostly pretty
straightforward, although there turned out to be surprisingly many
places we needed to add some handling; almost anywhere that touches
interfaces *or* named fragments needed some updates. But it's all
hopefully fairly clear code.
As a part of this change I made three semi-related improvements:
1. I refactored the handling of descriptions (i.e. GoDoc), because it
was getting more and more confusing and duplicative. I'm still not
sure how much of it it makes sense to inline vs. separate, but I
think this is better than it was. This resulted in some minor
changes to descriptions, generally in the direction of making things
more consistent.
2. I bumped the minimum Go version to 1.14 so we can guarantee support
for duplicate interface methods. These are useful for
abstract-in-absstract spreads; we generate an interface for the
fragment, and (if the fragment-type implements the scope-type) we
embed it into the interface we generate for its spread-context, and
if the two have a duplicated field we thus duplicate the method. It
wouldn't be impossible to support this on 1.13 (maybe just by
omitting said embed) but it didn't seem worth it. This also removes
a few special-cases in tests.
3. I added a bunch of code to better format syntax errors in the
generated code (which we see from `gofmt`). This is mostly just an
internal improvement; I wrote it because I got annoyed while hunting
down a few such errors..
Fixes, at last, #8.
Issue: https://github.com/Khan/genqlient/issues/8
## Test plan:
make check
Author: benjaminjkraft
Reviewers: dnerdy, benjaminjkraft, aberkan, MiguelCastillo
Required Reviewers:
Approved By: dnerdy
Checks: ✅ Lint, ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Lint
Pull Request URL: https://github.com/Khan/genqlient/pull/79
## Summary:
In previous commits I added support to genqlient for interfaces and
inline fragments. This means the only query structures that remain are
named fragments and their spreads, e.g.
```
fragment MyFragment on MyType { myField }
query MyQuery { getMyType { ...MyFragment } }
```
Other than mere completionism, these are potentially useful for code
sharing: you can spread the same fragment multiple places; and then
genqlient can notice that and generate the same type for each. (They
can even be shared between different queries in the same package.)
In this commit I add support for named fragments of concrete
(object/struct, not interface) type, spread into either concrete or
abstract scope. For genqlient's purposes, these are a new "root"
type-name, just like each operation, and are then embedded into the
appropriate struct. (Using embeds allows their fields to be referenced
as fields of the containing type, if convenient. Further design
considerations are discussed in DESIGN.md.)
This requires new code in two main places (plus miscellaneous glue),
both nontrivial but neither particularly complex:
- We need to actually traverse both structures and generate the types
(in `convert.go`).
- We need to decide which fragments from this package to send to the
server, both for good hyigene and because GraphQL requires we send
only ones this query uses (in `generate.go`).
- We need a little new wiring for options -- because fragments can be
shared between queries they get their own toplevel options, rather
than inheriting the query's options.
Finally, this required slightly subtler changes to how we do
unmarshaling (in `types.go` and `unmarshal.go.tmpl`). Basically,
because embedded fields' methods, including `UnmarshalJSON`, get
promoted to the parent type, and because the JSON library ignores their
fields when shadowed by those of the parent type, we need a little bit
of special logic in each such parent type to do its own unmarshal and
then delegate to each embed. This is similar (and much simpler) to
what we did for interfaces, although it required some changes to the
"method-hiding" trick (used for both). It's only really necessary in
certain specific cases (namely when an embedded type has an
`UnmarshalJSON` method or a field with the same name as the embedder),
but it's easier to just generate it always. This is all described in
more detail inline.
This does not support fragments of abstract type, which have their own
complexities. I'll address those, which are now the only remaining
piece of #8, in a future commit.
Issue: https://github.com/Khan/genqlient/issues/8
## Test plan:
make check
Author: benjaminjkraft
Reviewers: dnerdy, benjaminjkraft, aberkan, MiguelCastillo
Required Reviewers:
Approved By: dnerdy
Checks: ✅ Lint, ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Test (1.13), ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Test (1.13), ✅ Lint, ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Test (1.13), ✅ Lint
Pull Request URL: https://github.com/Khan/genqlient/pull/75
## Summary:
We had this setting called "scalars", which said: bind this GraphQL type
to this Go type, rather than the one you would normally use. It's
called that because it's most useful for custom scalars, where "the one
you would normally use" is "error: unknown scalar". But nothing ever
stopped you from using it for a non-scalar type. I was planning on
removing this functionality, because it's sort of a rough edge, but a
discussion with Craig found some good use cases, so instead, in this
commit, I document it better and add some slightly nicer ways to specify
it.
Specifically, here are a few potential non-scalar use cases:
- bind a GraphQL enum to a nonstandard type (or even `string`)
- bind an input type to some type that has exactly the fields you want;
this acts as a sort of workaround for issues #14 and #44
- bind an object type to your own struct, so as to add methods to it
(this is the use case Craig raised)
- bind an object type to your own struct, so as to share it between
multiple queries (I believe named fragments will address this case
better, but it doesn't hurt to have options)
- bind a GraphQL list type to a non-slice type in Go (presumably one
with an UnmarshalJSON method), or any other different structure
The latter three cases still have the sharp edge I was originally
worried about, which is that nothing guarantees that the fields you
request in the query are the ones the type expects to get. But I think
it's worth having the option, with appropriate disclaimers.
The main change to help support that better is that you can now specify
the type inline in the query, as an alternative to specifying it in the
config file; this means you might map a given object to a given struct,
but only in some cases, and when you do you have a chance to look at the
list of fields you're requesting.
Additionally, I renamed the config field from "scalars" to "bindings"
(but mentioned it in a few places where you might go looking for how to
map scalars, most importantly the error message you get for an unknown
(custom) scalar). While I was making a breaking change, I also changed
it to be a `map[string]<struct>` instead of a `map[string]string`,
because I expect to add more fields soon, e.g. to handle issue #38.
Finally, since the feature is now intended/documented, I added some
tests, although it's honestly quite simple on the genqlient side.
## Test plan:
make tesc
Author: benjaminjkraft
Reviewers: csilvers, aberkan, dnerdy, MiguelCastillo
Required Reviewers:
Approved by: csilvers
Checks: ⌛ Test (1.17), ⌛ Test (1.16), ⌛ Test (1.15), ⌛ Test (1.14), ⌛ Test (1.13), ⌛ Lint, ⌛ Test (1.17), ⌛ Test (1.16), ⌛ Test (1.15), ⌛ Test (1.14), ⌛ Test (1.13), ⌛ Lint
Pull request URL: https://github.com/Khan/genqlient/pull/69
## Summary:
Right now, if you make a query like `{ myInterface { field } }`, you
have to type-switch on all the possible implementations of `myInterface`
to get at `field`. Now, we generate getter-methods (e.g. `GetField`),
to make that access easier. Of course this only applies to shared
fields (which for now are the only ones, but once we support fragments
will no longer be).
This also includes a small change to the way we generate type-names for
interfaces: we no longer include the name of the concrete type in the
interface we propagate forward, so we generate
`MyInterfaceMyFieldMyType`, not `MyInterfaceMyImplMyFieldMyType`, in the
case where you have an interface `MyInterface` implemented by `MyImpl`
(and maybe other types) with field `myField: MyType`. This is necessary
so the getter method returns a well-defined type, and also probably
convenient for calling code. It will have to get a little bit more
complicated once we support fragments, where you could have two
implementing types with identically-named fields of different types, but
I think it'll be easiest to figure out how to deal with that when
implementing fragments.
While I was in the area, I added to the interface doc-comment a list of
the implementations. (In GraphQL, we're guaranteed to know them all
assuming our schema is up to date.)
Issue: https://github.com/Khan/genqlient/issues/8
## Test plan:
make check
Author: benjaminjkraft
Reviewers: benjaminjkraft, dnerdy, aberkan, MiguelCastillo
Required Reviewers:
Approved by: dnerdy
Checks: ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Test (1.13), ✅ Lint, ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Test (1.13), ✅ Lint
Pull request URL: https://github.com/Khan/genqlient/pull/57
## Summary:
In this commit I remove one of the limitations of our support for
interfaces, from #52, by adding support for list-of-interface fields.
This was surprisingly complex! The issue is that, as before, it's the
containing type that has to do all the glue work -- and it's that glue
work that is complicated by list-of-interface fields.
All in all, it's not that much new code, and by far the hard part is
just 20 lines in the UnmarshalJSON template (which come with almost
twice as many lines of comments to explain them). It may be easiest to
start by reading some of the generated code, and then read the template.
I also added support for such fields with `pointer: true` specified,
such that the type is `[][]...[]*MyInterface`, although I don't know why
you would want that. This does *not* allow e.g. `*[]*[][]*MyInterface`;
that would require a way to specify it (see #16) but also add some extra
complexity (as we'd have to actually walk the type-unwrap chain
properly, instead of just counting the number of slices and whether
there's a pointer).
Issue: https://github.com/Khan/genqlient/issues/8
## Test plan:
make check
Author: benjaminjkraft
Reviewers: dnerdy, benjaminjkraft, aberkan, csilvers, MiguelCastillo
Required Reviewers:
Approved by: dnerdy
Checks: ⌛ Test (1.17), ⌛ Test (1.16), ⌛ Test (1.15), ⌛ Test (1.14), ⌛ Test (1.13), ⌛ Lint, ⌛ Lint, ⌛ Test (1.17), ⌛ Test (1.16), ⌛ Test (1.15), ⌛ Test (1.14), ⌛ Test (1.13)
Pull request URL: https://github.com/Khan/genqlient/pull/54
## Summary:
In this commit I begin the journey to add the long-awaited support for
interfaces (part of #8). Well, it's not the beginning: I already had
some half-written broken code around. But it's the first fully
functional support, and especially, the first *tested* support; it's
probably best to review the nontrivially-changed code as if it were new.
Conceptually, the code so far is pretty simple: we generate an interface
type, and the implementations. (That code is in fact mostly unchanged.)
The complexity comes in because encoding/json doesn't know how to
unmarshal that. So we have to add an UnmarshalJSON method, which
actually has to be on the types with interface-type fields, that knows
how. I factored it into two methods, such that that UnmarshalJSON
method is just glue, and then there's a separate function, corresponding
to each interface-type, that actually does all the work. (If only one
could just write it as an actual method!) The method uses the same
trick suggested to me by a few others in another context to deserialize
all but one field, then handle that field specially, which is discussed
in the code.
This still has some limitations, which will be lifted in future commits:
- it doesn't allow for list-of-interface fields
- it requires that you manually ask for `__typename`
- it doesn't support fragments, i.e. you can only query for interface
fields, not concrete-type-specific ones
But it works, even in integration tests, which is progress!
As a part of this, I added a proper config option for the "allow broken
features" flag, since I need to be able to set it from the integration
tests which are in a separate package (and actually shell out via `go
generate`). I also renamed what was to be the first case
(InterfaceNoFragments), and replaced it with a further-simplified
version (avoiding list-of-interface fields.
[1] https://github.com/benjaminjkraft/notes/blob/master/go-json-interfaces.md
Issue: https://github.com/Khan/genqlient/issues/8
## Test plan:
make tesc
Author: benjaminjkraft
Reviewers: dnerdy, benjaminjkraft, aberkan, csilvers, MiguelCastillo
Required Reviewers:
Approved by: dnerdy
Checks: ⌛ Test (1.17), ✅ Test (1.16), ⌛ Test (1.15), ⌛ Test (1.14), ⌛ Test (1.13), ✅ Lint, ✅ Test (1.17), ⌛ Test (1.16), ⌛ Test (1.15), ⌛ Test (1.14), ⌛ Test (1.13), ✅ Lint
Pull request URL: https://github.com/Khan/genqlient/pull/52
## Summary:
I've felt for a while that types.go is way too confusing, and as I
started to implement some of the more complex cases of generating
interface-types, the cracks were really starting to show. Luckily, I
also finally realized how to fix it: we need to separate the process of
traversing the GraphQL operation and schema to decide what types to
generate from the process of actually generating those types. This
requires an extra set of intermediate data structures, but I think it
makes things quite a lot easier to understand -- and, importantly, it
means that the code-generation doesn't need to go in the order we
traverse the query/schema.
So in this commit, I did that huge refactor. It's probably best to just
review types.go and traverse.go as if they were new; the old code was
quite hard to understand and the new code will hopefully make a lot more
sense. (And to that end, review comments about what could be organized
better or needs more documentation are very much in order, even for code
that is mostly unchanged.)
This does introduce one bug, sort of, which is that rather than
generating broken code for list-of-interface fields, we generate no code
at all. (A TODO in unmarshal.go describes why.) I'll fix this when I
add support for those fields. (It's all behind the AllowBrokenFeatures
flag, anyway.) Otherwise, the only changes to generated code are that a
few methods are ordered differently, because we now generate the
implements-interface methods with the interface, rather than the
implementations, as it's much simpler that way. (In GraphQL, unlike Go,
we know the list of all possible implementations of each interface, so
this is possible.)
## Test plan:
golangci-lint run ./... && go test ./...
Author: benjaminjkraft
Reviewers: dnerdy, benjaminjkraft, aberkan, csilvers, MiguelCastillo
Required Reviewers:
Approved by: dnerdy
Checks: ✅ Lint, ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Test (1.13), ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Test (1.13), ✅ Lint
Pull request URL: https://github.com/Khan/genqlient/pull/51
## Summary:
It would be nice to have some linting beyond `go vet`! Now we do. I
started by copying the config from Khan/webapp. I did remove a couple
of staticcheck checks that I didn't feel were useful. (Note also that
exportloopref is the replacement for scopelint in newer golangci-lint.)
Included are all the needed lint fixes; most are stylistic but the
changes in the example are a (minor) bugfix.
Fixes#22.
Issue: https://github.com/Khan/genqlient/issues/22
## Test plan:
make check
Author: benjaminjkraft
Reviewers: aberkan, dnerdy, benjaminjkraft, csilvers, MiguelCastillo
Required Reviewers:
Approved by: aberkan, dnerdy
Checks: ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Test (1.13), ✅ Lint, ✅ Test (1.17), ✅ Test (1.16), ✅ Test (1.15), ✅ Test (1.14), ✅ Test (1.13), ✅ Lint
Pull request URL: https://github.com/Khan/genqlient/pull/49
Craig pointed out this is a bit confusing when you don't have all the
fields. Now we say so, but still include the type's description in case
it's useful.
Fixes#37.
