On Mon, Oct 2, 2023 at 3:07 PM John Snow <js...@redhat.com> wrote:
>
> On Wed, Sep 27, 2023 at 7:25 AM Victor Toso <victort...@redhat.com> wrote:
> >
> > This patch handles QAPI enum types and generates its equivalent in Go.
> >
> > Basically, Enums are being handled as strings in Golang.
> >
> > 1. For each QAPI enum, we will define a string type in Go to be the
> > assigned type of this specific enum.
> >
> > 2. Naming: CamelCase will be used in any identifier that we want to
> > export [0], which is everything.
> >
> > [0] https://go.dev/ref/spec#Exported_identifiers
> >
> > Example:
> >
> > qapi:
> > | { 'enum': 'DisplayProtocol',
> > | 'data': [ 'vnc', 'spice' ] }
> >
> > go:
> > | type DisplayProtocol string
> > |
> > | const (
> > | DisplayProtocolVnc DisplayProtocol = "vnc"
> > | DisplayProtocolSpice DisplayProtocol = "spice"
> > | )
> >
> > Signed-off-by: Victor Toso <victort...@redhat.com>
> > ---
> > scripts/qapi/golang.py | 140 +++++++++++++++++++++++++++++++++++++++++
> > scripts/qapi/main.py | 2 +
> > 2 files changed, 142 insertions(+)
> > create mode 100644 scripts/qapi/golang.py
> >
> > diff --git a/scripts/qapi/golang.py b/scripts/qapi/golang.py
> > new file mode 100644
> > index 0000000000..87081cdd05
> > --- /dev/null
> > +++ b/scripts/qapi/golang.py
> > @@ -0,0 +1,140 @@
> > +"""
> > +Golang QAPI generator
> > +"""
> > +# Copyright (c) 2023 Red Hat Inc.
> > +#
> > +# Authors:
> > +# Victor Toso <victort...@redhat.com>
> > +#
> > +# This work is licensed under the terms of the GNU GPL, version 2.
> > +# See the COPYING file in the top-level directory.
> > +
> > +# due QAPISchemaVisitor interface
> > +# pylint: disable=too-many-arguments
"due to" - also, you could more selectively disable this warning by
putting this comment in the body of the QAPISchemaVisitor class which
would make your exemption from the linter more locally obvious.
> > +
> > +# Just for type hint on self
> > +from __future__ import annotations
Oh, you know - it's been so long since I worked on QAPI I didn't
realize we had access to this now. That's awesome!
(It was introduced in Python 3.7+)
> > +
> > +import os
> > +from typing import List, Optional
> > +
> > +from .schema import (
> > + QAPISchema,
> > + QAPISchemaType,
> > + QAPISchemaVisitor,
> > + QAPISchemaEnumMember,
> > + QAPISchemaFeature,
> > + QAPISchemaIfCond,
> > + QAPISchemaObjectType,
> > + QAPISchemaObjectTypeMember,
> > + QAPISchemaVariants,
> > +)
> > +from .source import QAPISourceInfo
> > +
Try running isort here:
> cd ~/src/qemu/scripts
> isort -c qapi/golang.py
ERROR: /home/jsnow/src/qemu/scripts/qapi/golang.py Imports are
incorrectly sorted and/or formatted.
you can have it fix the import order for you:
> isort qapi/golang.py
It's very pedantic stuff, but luckily there's a tool to just handle it for you.
> > +TEMPLATE_ENUM = '''
> > +type {name} string
> > +const (
> > +{fields}
> > +)
> > +'''
> > +
> > +
> > +def gen_golang(schema: QAPISchema,
> > + output_dir: str,
> > + prefix: str) -> None:
> > + vis = QAPISchemaGenGolangVisitor(prefix)
> > + schema.visit(vis)
> > + vis.write(output_dir)
> > +
> > +
> > +def qapi_to_field_name_enum(name: str) -> str:
> > + return name.title().replace("-", "")
> > +
> > +
> > +class QAPISchemaGenGolangVisitor(QAPISchemaVisitor):
> > +
> > + def __init__(self, _: str):
> > + super().__init__()
> > + types = ["enum"]
> > + self.target = {name: "" for name in types}
you *could* say:
types = ("enum",)
self.target = dict.fromkeys(types, "")
1. We don't need a list because we won't be modifying it, so a tuple suffices
2. There's an idiom for doing what you want that reads a little better
3. None of it really matters, though.
Also keep in mind you don't *need* to initialize a dict in this way,
you can just arbitrarily assign into it whenever you'd like.
sellf.target['enum'] = foo
I don't know if that makes things easier or not with however the
subsequent patches are written.
> > + self.schema = None
> > + self.golang_package_name = "qapi"
> > +
> > + def visit_begin(self, schema):
> > + self.schema = schema
> > +
> > + # Every Go file needs to reference its package name
> > + for target in self.target:
> > + self.target[target] = f"package {self.golang_package_name}\n"
> > +
> > + def visit_end(self):
> > + self.schema = None
> > +
> > + def visit_object_type(self: QAPISchemaGenGolangVisitor,
> > + name: str,
> > + info: Optional[QAPISourceInfo],
> > + ifcond: QAPISchemaIfCond,
> > + features: List[QAPISchemaFeature],
> > + base: Optional[QAPISchemaObjectType],
> > + members: List[QAPISchemaObjectTypeMember],
> > + variants: Optional[QAPISchemaVariants]
> > + ) -> None:
> > + pass
> > +
> > + def visit_alternate_type(self: QAPISchemaGenGolangVisitor,
> > + name: str,
> > + info: Optional[QAPISourceInfo],
> > + ifcond: QAPISchemaIfCond,
> > + features: List[QAPISchemaFeature],
> > + variants: QAPISchemaVariants
> > + ) -> None:
> > + pass
> > +
> > + def visit_enum_type(self: QAPISchemaGenGolangVisitor,
Was there a problem when you omitted the type for 'self'? Usually that
can be inferred. As of this patch, at least, I think this can be
safely dropped. (Maybe it becomes important later.)
> > + name: str,
> > + info: Optional[QAPISourceInfo],
> > + ifcond: QAPISchemaIfCond,
> > + features: List[QAPISchemaFeature],
> > + members: List[QAPISchemaEnumMember],
> > + prefix: Optional[str]
> > + ) -> None:
> > +
> > + value = qapi_to_field_name_enum(members[0].name)
>
> Unsure if this was addressed on the mailing list yet, but in our call
> we discussed how this call was vestigial and was causing the QAPI
> tests to fail. Actually, I can't quite run "make check-qapi-schema"
> and see the failure, I'm seeing it when I run "make check" and I'm not
> sure how to find the failure more efficiently/quickly:
>
> jsnow@scv ~/s/q/build (review)> make
> [1/60] Generating subprojects/dtc/version_gen.h with a custom command
> [2/60] Generating qemu-version.h with a custom command (wrapped by
> meson to capture output)
> [3/44] Generating tests/Test QAPI files with a custom command
> FAILED: tests/qapi-builtin-types.c tests/qapi-builtin-types.h
> tests/qapi-builtin-visit.c tests/qapi-builtin-visit.h
> tests/test-qapi-commands-sub-sub-module.c
> tests/test-qapi-commands-sub-sub-module.h tests/test-qapi-commands.c
> tests/test-qapi-commands.h tests/test-qapi-emit-events.c
> tests/test-qapi-emit-events.h tests/test-qapi-events-sub-sub-module.c
> tests/test-qapi-events-sub-sub-module.h tests/test-qapi-events.c
> tests/test-qapi-events.h tests/test-qapi-init-commands.c
> tests/test-qapi-init-commands.h tests/test-qapi-introspect.c
> tests/test-qapi-introspect.h tests/test-qapi-types-sub-sub-module.c
> tests/test-qapi-types-sub-sub-module.h tests/test-qapi-types.c
> tests/test-qapi-types.h tests/test-qapi-visit-sub-sub-module.c
> tests/test-qapi-visit-sub-sub-module.h tests/test-qapi-visit.c
> tests/test-qapi-visit.h
> /home/jsnow/src/qemu/build/pyvenv/bin/python3
> /home/jsnow/src/qemu/scripts/qapi-gen.py -o
> /home/jsnow/src/qemu/build/tests -b -p test-
> ../tests/qapi-schema/qapi-schema-test.json --suppress-tracing
> Traceback (most recent call last):
> File "/home/jsnow/src/qemu/scripts/qapi-gen.py", line 19, in <module>
> sys.exit(main.main())
> ^^^^^^^^^^^
> File "/home/jsnow/src/qemu/scripts/qapi/main.py", line 96, in main
> generate(args.schema,
> File "/home/jsnow/src/qemu/scripts/qapi/main.py", line 58, in generate
> gen_golang(schema, output_dir, prefix)
> File "/home/jsnow/src/qemu/scripts/qapi/golang.py", line 46, in gen_golang
> schema.visit(vis)
> File "/home/jsnow/src/qemu/scripts/qapi/schema.py", line 1227, in visit
> mod.visit(visitor)
> File "/home/jsnow/src/qemu/scripts/qapi/schema.py", line 209, in visit
> entity.visit(visitor)
> File "/home/jsnow/src/qemu/scripts/qapi/schema.py", line 346, in visit
> visitor.visit_enum_type(
> File "/home/jsnow/src/qemu/scripts/qapi/golang.py", line 102, in
> visit_enum_type
> value = qapi_to_field_name_enum(members[0].name)
> ~~~~~~~^^^
> IndexError: list index out of range
> ninja: build stopped: subcommand failed.
> make: *** [Makefile:162: run-ninja] Error 1
>
>
> For the rest of my review, I commented this line out and continued on.
>
> > + fields = ""
> > + for member in members:
> > + value = qapi_to_field_name_enum(member.name)
> > + fields += f'''\t{name}{value} {name} = "{member.name}"\n'''
> > +
> > + self.target["enum"] += TEMPLATE_ENUM.format(name=name,
> > fields=fields[:-1])
This line is a little too long. (sorry)
try:
cd ~/src/qemu/scripts
flake8 qapi/
jsnow@scv ~/s/q/scripts (review)> flake8 qapi/
qapi/main.py:60:1: E302 expected 2 blank lines, found 1
qapi/golang.py:106:80: E501 line too long (82 > 79 characters)
> > +
> > + def visit_array_type(self, name, info, ifcond, element_type):
> > + pass
> > +
> > + def visit_command(self,
> > + name: str,
> > + info: Optional[QAPISourceInfo],
> > + ifcond: QAPISchemaIfCond,
> > + features: List[QAPISchemaFeature],
> > + arg_type: Optional[QAPISchemaObjectType],
> > + ret_type: Optional[QAPISchemaType],
> > + gen: bool,
> > + success_response: bool,
> > + boxed: bool,
> > + allow_oob: bool,
> > + allow_preconfig: bool,
> > + coroutine: bool) -> None:
> > + pass
> > +
> > + def visit_event(self, name, info, ifcond, features, arg_type, boxed):
> > + pass
> > +
> > + def write(self, output_dir: str) -> None:
> > + for module_name, content in self.target.items():
> > + go_module = module_name + "s.go"
> > + go_dir = "go"
> > + pathname = os.path.join(output_dir, go_dir, go_module)
> > + odir = os.path.dirname(pathname)
> > + os.makedirs(odir, exist_ok=True)
> > +
> > + with open(pathname, "w", encoding="ascii") as outfile:
> > + outfile.write(content)
> > diff --git a/scripts/qapi/main.py b/scripts/qapi/main.py
> > index 316736b6a2..cdbb3690fd 100644
> > --- a/scripts/qapi/main.py
> > +++ b/scripts/qapi/main.py
> > @@ -15,6 +15,7 @@
> > from .common import must_match
> > from .error import QAPIError
> > from .events import gen_events
> > +from .golang import gen_golang
> > from .introspect import gen_introspect
> > from .schema import QAPISchema
> > from .types import gen_types
> > @@ -54,6 +55,7 @@ def generate(schema_file: str,
> > gen_events(schema, output_dir, prefix)
> > gen_introspect(schema, output_dir, prefix, unmask)
> >
> > + gen_golang(schema, output_dir, prefix)
> >
> > def main() -> int:
> > """
> > --
> > 2.41.0
> >
