音楽で楽しみましょう！-Let's have fun with music!-

Signed-off-by: Shin'ya Minazuki <shinyoukai@laidback.moe>

api/funquail_api/common/fields.py

@@ -0,0 +1,177 @@
+import django_filters
+from django import forms
+from django.core.serializers.json import DjangoJSONEncoder
+from django.db import models
+from rest_framework import serializers
+
+from . import search
+
+PRIVACY_LEVEL_CHOICES = [
+    ("me", "Only me"),
+    ("followers", "Me and my followers"),
+    ("instance", "Everyone on my instance, and my followers"),
+    ("everyone", "Everyone, including people on other instances"),
+]
+
+
+def get_privacy_field():
+    return models.CharField(
+        max_length=30, choices=PRIVACY_LEVEL_CHOICES, default="instance"
+    )
+
+
+def privacy_level_query(user, lookup_field="privacy_level", user_field="user"):
+    if user.is_anonymous:
+        return models.Q(**{lookup_field: "everyone"})
+
+    return models.Q(**{f"{lookup_field}__in": ["instance", "everyone"]}) | models.Q(
+        **{lookup_field: "me", user_field: user}
+    )
+
+
+class SearchFilter(django_filters.CharFilter):
+    def __init__(self, *args, **kwargs):
+        self.search_fields = kwargs.pop("search_fields")
+        self.fts_search_fields = kwargs.pop("fts_search_fields", [])
+        super().__init__(*args, **kwargs)
+
+    def filter(self, qs, value):
+        if not value:
+            return qs
+        if self.fts_search_fields:
+            query = search.get_fts_query(
+                value, self.fts_search_fields, model=self.parent.Meta.model
+            )
+        else:
+            query = search.get_query(value, self.search_fields)
+        return qs.filter(query)
+
+
+class SmartSearchFilter(django_filters.CharFilter):
+    def __init__(self, *args, **kwargs):
+        self.config = kwargs.pop("config")
+        super().__init__(*args, **kwargs)
+
+    def filter(self, qs, value):
+        if not value:
+            return qs
+        try:
+            cleaned = self.config.clean(value)
+        except forms.ValidationError:
+            return qs.none()
+        return search.apply(qs, cleaned)
+
+
+def get_generic_filter_query(value, relation_name, choices):
+    parts = value.split(":", 1)
+    type = parts[0]
+    try:
+        conf = choices[type]
+    except KeyError:
+        raise forms.ValidationError("Invalid type")
+    related_queryset = conf["queryset"]
+    related_model = related_queryset.model
+    filter_query = models.Q(
+        **{
+            "{}_content_type__app_label".format(
+                relation_name
+            ): related_model._meta.app_label,
+            "{}_content_type__model".format(
+                relation_name
+            ): related_model._meta.model_name,
+        }
+    )
+    if len(parts) > 1:
+        id_attr = conf.get("id_attr", "id")
+        id_field = conf.get("id_field", serializers.IntegerField(min_value=1))
+        try:
+            id_value = parts[1]
+            id_value = id_field.to_internal_value(id_value)
+        except (TypeError, KeyError, serializers.ValidationError):
+            raise forms.ValidationError("Invalid id")
+        query_getter = conf.get(
+            "get_query", lambda attr, value: models.Q(**{attr: value})
+        )
+        obj_query = query_getter(id_attr, id_value)
+        try:
+            obj = related_queryset.get(obj_query)
+        except related_queryset.model.DoesNotExist:
+            raise forms.ValidationError("Invalid object")
+        filter_query &= models.Q(**{f"{relation_name}_id": obj.id})
+
+    return filter_query
+
+
+class GenericRelationFilter(django_filters.CharFilter):
+    def __init__(self, relation_name, choices, *args, **kwargs):
+        self.relation_name = relation_name
+        self.choices = choices
+        super().__init__(*args, **kwargs)
+
+    def filter(self, qs, value):
+        if not value:
+            return qs
+        try:
+            filter_query = get_generic_filter_query(
+                value, relation_name=self.relation_name, choices=self.choices
+            )
+        except forms.ValidationError:
+            return qs.none()
+        return qs.filter(filter_query)
+
+
+class GenericRelation(serializers.JSONField):
+    def __init__(self, choices, *args, **kwargs):
+        self.choices = choices
+        self.encoder = kwargs.setdefault("encoder", DjangoJSONEncoder)
+        super().__init__(*args, **kwargs)
+
+    def to_representation(self, value):
+        if not value:
+            return
+        type = None
+        id = None
+        id_attr = None
+        for key, choice in self.choices.items():
+            if isinstance(value, choice["queryset"].model):
+                type = key
+                id_attr = choice.get("id_attr", "id")
+                id = getattr(value, id_attr)
+                break
+
+        if type:
+            return {"type": type, id_attr: id}
+
+    def to_internal_value(self, v):
+        v = super().to_internal_value(v)
+
+        if not v or not isinstance(v, dict):
+            raise serializers.ValidationError("Invalid data")
+
+        try:
+            type = v["type"]
+            field = serializers.ChoiceField(choices=list(self.choices.keys()))
+            type = field.to_internal_value(type)
+        except (TypeError, KeyError, serializers.ValidationError):
+            raise serializers.ValidationError("Invalid type")
+
+        conf = self.choices[type]
+        id_attr = conf.get("id_attr", "id")
+        id_field = conf.get("id_field", serializers.IntegerField(min_value=1))
+        queryset = conf["queryset"]
+        try:
+            id_value = v[id_attr]
+            id_value = id_field.to_internal_value(id_value)
+        except (TypeError, KeyError, serializers.ValidationError):
+            raise serializers.ValidationError(f"Invalid {id_attr}")
+
+        query_getter = conf.get(
+            "get_query", lambda attr, value: models.Q(**{attr: value})
+        )
+        query = query_getter(id_attr, id_value)
+        try:
+            obj = queryset.get(query)
+        except queryset.model.DoesNotExist:
+            raise serializers.ValidationError("Object not found")
+
+        return obj