如何将RichTextField迁移到StreamField?

时间:2019-05-01 19:38:32

标签: wagtail

在我的博客文章模型中,我试图将RichTextField迁移到StreamField。我关注了Wagtail文档“将RichTextFields迁移到StreamField”,包括有关迁移具有修订版本的博客文章的部分。他们没有效果。如何将RichTextField转换为StreamField?

这是针对使用Django 1.11.13,Wagtail 2.1和PostgreSQL的博客的。我有200多个博客文章,其中许多具有“实时+草案”状态,这意味着它们尚未发布。我检查了数据库中的博客文章,看起来它们的正文字段存储为HTML。

我复制了文档中的代码,并更改了所有引用以与自己的项目相关。运行迁移后,我得到了AttributeError,找不到“ raw_text”。所以我创建了一个异常来传递它。我应用了迁移,一切顺利。

然后在models.py中,将类的body属性从RichTextField更改为带有RichFieldBlock的StreamField。我还将其内容面板从FieldPanel更改为StreamFieldPanel。我应用了此迁移,并以OK结束。

当我在Wagtail admin中查看一些帖子时,所有具有Live + Draft状态的帖子都转换为StreamFields内的RichTextBlocks,但是它们的内容被包装在名为{'rich_text':''}的JSON对象中。 JSON对象的样式与编辑器中其余文本的样式不同。当我实时查看这些帖子时,没有显示任何数据,我认为是因为模板无法读取JSON。所有具有“实时”状态的博客帖子也都将RichTextField转换为StreamField,但是其内容为空。他们的数据已从编辑器中删除。当我查看他们的直播时,他们一片空白。但是,当我在数据库中检查它们时,它们的主体字段仍然包含我看到的以前的HTML。

这是管理员中的实时+草稿帖子:

This is a Live+Draft post in admin

这是管理员的实时帖子:

This is a Live post in admin

在运行两次迁移并看到奇数数据之后,我尝试安装数据库的新副本,但这并不能改善问题。

template.html:

<section>
    {{ page.body }}
</section>
在运行转换迁移之前,

models.py:

class BlogPost(Page):

    body = RichTextField(blank=True)

    content_panels = Page.content_panels + [
            FieldPanel('body'),
        ]

migration.py,我在page_to_streamfield()函数中添加了AttributeError异常,因为未找到raw_text:

# -*- coding: utf-8 -*-
# Generated by Django 1.11.13 on 2019-05-01 13:46
from __future__ import unicode_literals

import json

from django.core.serializers.json import DjangoJSONEncoder
from django.db import migrations, models

from wagtail.core.rich_text import RichText


def page_to_streamfield(page):
    changed = False
    try:
        if page.body.raw_text and not page.body:
            page.body = [('rich_text', {'rich_text': RichText(page.body.raw_text)})]
            changed = True
    except AttributeError:
        pass
    return page, changed


def pagerevision_to_streamfield(revision_data):
    changed = False
    body = revision_data.get('body')
    if body:
        try:
            json.loads(body)
        except ValueError:
            revision_data['body'] = json.dumps(
                [{
                    "value": {"rich_text": body},
                    "type": "rich_text"
                }],
                cls=DjangoJSONEncoder)
            changed = True
        else:
            # It's already valid JSON. Leave it.
            pass
    return revision_data, changed


def page_to_richtext(page):
    changed = False
    if page.body.raw_text is None:
        raw_text = ''.join([
            child.value['rich_text'].source for child in page.body
            if child.block_type == 'rich_text'
        ])
        page.body = raw_text
        changed = True
    return page, changed


def pagerevision_to_richtext(revision_data):
    changed = False
    body = revision_data.get('body', 'definitely non-JSON string')
    if body:
        try:
            body_data = json.loads(body)
        except ValueError:
            # It's not apparently a StreamField. Leave it.
            pass
        else:
            raw_text = ''.join([
                child['value']['rich_text'] for child in body_data
                if child['type'] == 'rich_text'
            ])
            revision_data['body'] = raw_text
            changed = True
    return revision_data, changed


def convert(apps, schema_editor, page_converter, pagerevision_converter):
    BlogPage = apps.get_model("blog", "BlogPost")
    for page in BlogPage.objects.all():

        page, changed = page_converter(page)
        if changed:
            page.save()

        for revision in page.revisions.all():
            revision_data = json.loads(revision.content_json)
            revision_data, changed = pagerevision_converter(revision_data)
            if changed:
                revision.content_json = json.dumps(revision_data, cls=DjangoJSONEncoder)
                revision.save()


def convert_to_streamfield(apps, schema_editor):
    return convert(apps, schema_editor, page_to_streamfield, pagerevision_to_streamfield)


def convert_to_richtext(apps, schema_editor):
    return convert(apps, schema_editor, page_to_richtext, pagerevision_to_richtext)


class Migration(migrations.Migration):

    dependencies = [
        # leave the dependency line from the generated migration intact!
        ('blog', 'previous_migration'),
    ]

    operations = [
        migrations.RunPython(
            convert_to_streamfield,
            convert_to_richtext,
        ),
    ]

models.py运行上一次迁移后,我手动将其更改为StreamField并针对此更改运行了第二次迁移:

class BlogPost(Page):

    body = StreamField([
            ('rich_text', blocks.RichTextBlock())
        ], blank=True)

    content_panels = Page.content_panels + [
            StreamFieldPanel('body'),
        ]

我希望在Wagtail管理员的StreamField内看到博客文章的数据,但是它是空白的或包装在JSON对象中。

1 个答案:

答案 0 :(得分:1)

使用此脚本,我能够使用RichTextBlock将RichTextField迁移到StreamField(假定架构类似于Wagtail入门教程的前三章)。我发现通过将其分为不同的步骤可以更轻松地考虑此过程:从备份/进行备份,模式迁移,数据迁移以及管理/模板更改中获得新的数据库。我发现我需要遍历每个BlogPost及其所有关联的PageRevision。编辑实时发布的数据非常简单,但是草稿以序列化JSON的形式存储在两个级别的深度,这很难弄清楚如何进行交互。希望该脚本可以帮助其他人。注意:此脚本不会反向迁移。

0004_convert_data.py

import json
from django.db import migrations
import wagtail.core.fields
from wagtail.core.rich_text import RichText


def convert_data(apps, schema_editor):
    blog_page = apps.get_model('blog', 'BlogPage')
    for post in blog_page.objects.all():
        print('\n', post.title)
        # edit the live post
        if post.body.raw_text and not post.body:
            post.body = [('paragraph', RichText(post.body.raw_text))]
            print('Updated ' + post.title)
            post.save()

        # edit drafts associated with post
        if post.has_unpublished_changes:
            print(post.title + ' has drafts...')
            for rev in post.revisions.all():
                data = json.loads(rev.content_json)
                body = data['body']
                print(body)

                print('This is current JSON:', data, '\n')
                data['body'] = json.dumps([{
                    "type": "paragraph",
                    "value": body
                }])
                rev.content_json = json.dumps(data)
                print('This is updated JSON:', rev.content_json, '\n')

                rev.save()

        print('Completed ' + post.title + '.' + '\n')


class Migration(migrations.Migration):

    dependencies = [
        ('blog', '0003_blogpage_stream'),
    ]

    operations = [
        migrations.AlterField(
            model_name='blogpage',
            name='body',
            field=wagtail.core.fields.StreamField([('paragraph', wagtail.core.blocks.RichTextBlock())], blank=True),
        ),

        migrations.RunPython(convert_data),
    ]

models.py

from django.db import models

from wagtail.core.models import Page
from wagtail.core import blocks
from wagtail.core.fields import RichTextField, StreamField
from wagtail.admin.edit_handlers import FieldPanel, StreamFieldPanel
from wagtail.images.blocks import ImageChooserBlock
from wagtail.search import index


class BlogIndexPage(Page):
    intro = RichTextField(blank=True)

    content_panels = Page.content_panels + [
        FieldPanel('intro', classname="full")
    ]


class BlogPage(Page):
    date = models.DateField("Post date")
    intro = models.CharField(max_length=250)
    # body = RichTextField(blank=True)
    body = StreamField([
        ('paragraph', blocks.RichTextBlock()),
    ], blank=True)
    stream = StreamField([
        ('heading', blocks.CharBlock(classname="full title")),
        ('paragraph', blocks.RichTextBlock()),
        ('image', ImageChooserBlock()),
    ], blank=True)

    search_fields = Page.search_fields + [
        index.SearchField('intro'),
        index.SearchField('body'),
    ]

    content_panels = Page.content_panels + [
        FieldPanel('date'),
        FieldPanel('intro'),
        StreamFieldPanel('body'),
        StreamFieldPanel('stream'),
    ]


templates / blog / blog_page.html

{% extends "base.html" %}

{% load wagtailcore_tags %}

{% block body_class %}template-blogpage{% endblock %}

{% block content %}
    <h1>{{ page.title }}</h1>
    <p class="meta">{{ page.date }}</p>

    <div class="intro">{{ page.intro }}</div>

    {{ page.body }}

    <p><a href="{{ page.get_parent.url }}">Return to blog</a></p>

{% endblock %}