Django如何在過濾后在多個模型上注釋關鍵字實例的總數？

Question

好的，所以我有一個“關鍵字”模型，該模型存儲着我的其他4個模型的關鍵字，每個模型都有一個“ key_list”字段，該字段是一個指向“關鍵字”模型的ManyToManyField 。 我的每個模型都有多個關鍵字，我正在搜索它們並成功找到它們，如下所示：

keys_selected='term1$term2$term3$'
keys_selected = keys_selected.rstrip('$')
keys_selected = keys_selected.split('$')
goal = len(keys_selected)
remaining = list()
remaining += Keyword.objects.filter(employee__key_list__key__in=keys_selected).annotate(num_keys=Count('key')).filter(num_keys=goal).distinct()
remaining += Keyword.objects.filter(vendor__key_list__key__in=keys_selected).annotate(num_keys=Count('key')).filter(num_keys=goal).distinct()
remaining += Keyword.objects.filter(application__key_list__key__in=keys_selected).annotate(num_keys=Count('key')).filter(num_keys=goal).distinct()
remaining += Keyword.objects.filter(machine__key_list__key__in=keys_selected).annotate(num_keys=Count('key')).filter(num_keys=goal).distinct()
key_list = list()
for x in remaining:
    if x not in key_list:
        key_list.append(x)

這將返回分配給我的4個模型中包含我選擇的術語的所有條目的所有關鍵字的字典。 這里的想法是創建一個過濾器，以可視方式顯示與我的搜索查詢匹配的對象的key_list中所有關鍵字的key_list 。 我希望將其附加到輸出到上下文的字典中，以便隨后可以調用該值並將其用於字體大小，如下所示：

{% for key in key_list %}
<a href="{% url 'keysearch:index' %}?keys_selected={{ key }}${{ keys_selected }}" style="font-size: {{ key.num_keys }}px;">({{ key }})</a>
{% endfor %}

換句話說，這應該為我的關鍵字創建一個關鍵字“雲”，該關鍵字會過濾並直觀地顯示給定關鍵字在我的模型結果中的出現頻率，但是我完全迷失了如何使該關鍵字僅在我的結果中起作用過濾。 我不知道如何在多個模型中完成此操作。

我的型號供參考：

class Keyword(models.Model):
    key = models.CharField(max_length=2000, unique=True)

    def __str__(self):
        return self.key

    class Meta:
        ordering = ('key',)


class Entries(models.Model):
    name = models.CharField("Name", max_length=200)
    updated = models.DateTimeField("Last Updated", auto_now=True)
    key_list = models.ManyToManyField(Keyword, blank=True, verbose_name="Keywords")
    description = models.TextField("Description", blank=True)

    class Meta:
        abstract = True
        ordering = ('name',)


class Employee(Entries):
    uid = models.SlugField("Employee User ID", max_length=6, unique=True, blank=True)
    manager = models.SlugField("Manager's User ID", max_length=6)

    def __str__(self):
        return self.name


class Vendor(Entries):
    company = models.CharField("Vendor Company", max_length=200)
    email = models.EmailField("Vendor Company Email Address", max_length=254, unique=True)
    vend_man_name = models.CharField("Manager's Name", max_length=200)
    vend_man_email = models.EmailField("Manager's Email Address", max_length=254)

    def __str__(self):
        return self.name


class Application(Entries):
    app_url = models.URLField("Application URL", max_length=800, unique=True)

    def __str__(self):
        return self.name


class Machine(Entries):
    address = models.CharField("Machine Address", max_length=800, unique=True)
    phys_loc = models.TextField("Physical Location", blank=True)

    def __str__(self):
        return self.name

Answer 1

在此處找到了使用groupby的Lauritz V. Thaulow的答案。

我的解決方案（包括他的代碼）：

from django.db.models import Count
from keysearch.models import Employee, Vendor, Application, Machine, Keyword
from itertools import groupby


def unique_keys(input):
    output = []
    for x in input:
        if x not in output:
            output.append(x)
    return output


def canonicalize_dict(x):
    return sorted(x.items(), key=lambda x: hash(x[0]))


def unique_and_count(lst):
    grouper = groupby(sorted(map(canonicalize_dict, lst)))
    return [dict(k + [("count", int(len(list(g)) * 2.3 + 16))]) for k, g in grouper]


def keycount(key_list='', keys_selected=''):
    goal = len(keys_selected)
    key_ref = list()
    db_list = [Employee, Vendor, Application, Machine]
    for db in db_list:
        if keys_selected == '':
            source = db.objects.all()
        else:
            source = db.objects.filter(key_list__key__in=keys_selected).annotate(num_keys=Count('key_list')).filter(num_keys=goal).distinct()
        for entry in source:
            key_ref += entry.key_list.values()
    key_list = unique_and_count(key_ref)
    return key_list

@register.inclusion_tag('keysearch/key_cloud.html')
def key_cloud(keys_selected=''):
    if keys_selected == '':
        key_list = Keyword.objects.all()
        key_list = keycount(key_list, keys_selected)
    else:
        keys_selected = keys_selected.rstrip('$')
        keys_selected = keys_selected.split('$')
        keys_selected = unique_keys(keys_selected)
        goal = len(keys_selected)
        remaining = list()
        remaining += Keyword.objects.filter(employee__key_list__key__in=keys_selected).annotate(num_keys=Count('key')).filter(num_keys=goal)
        remaining += Keyword.objects.filter(vendor__key_list__key__in=keys_selected).annotate(num_keys=Count('key')).filter(num_keys=goal)
        remaining += Keyword.objects.filter(application__key_list__key__in=keys_selected).annotate(num_keys=Count('key')).filter(num_keys=goal)
        remaining += Keyword.objects.filter(machine__key_list__key__in=keys_selected).annotate(num_keys=Count('key')).filter(num_keys=goal)
        key_list = unique_keys(remaining)
        key_list = keycount(key_list, keys_selected)
        keys_selected = "$".join(keys_selected)
        keys_selected += '$'
    context = {'key_list': key_list, 'keys_selected': keys_selected}
    return context

然后在模板中：

{% for key in key_list %}
    <a href="{% url 'keysearch:index' %}?keys_selected={{ key.key }}${{ keys_selected }}" style="font-size: {{ key.count }}px;">({{ key.key }})</a>
{% empty %}
    <div class="w3-card-2 w3-black w3-center w3-rest"><h4>There are no key queries with this combination.</h4></div>
{% endfor %}