为了使您的帖子具有默认图像，您需要设置帖子缩略图。在执行此操作时，您需要设置媒体的ID，但这并不明显。

我的大部分工作都是用Python完成的，因此对我来说，以下内容很有帮助：

Step 1. 获取所有媒体的列表，以便了解ID

##
## Retrieve a list of media

# curl -X OPTIONS -i http://demo.wp-api.org/wp-json/wp/v2/posts
import json
import pycurl
import re
from io import BytesIO
import pandas as pd
import datetime
import urllib3


wpUrl = "https://MyWordPRessSite.COM</wp-json/wp/v2/media?page={}"

bContinue = True
page=1
while bContinue == True:
    buffer = BytesIO()
    c = pycurl.Curl()
    c.setopt(pycurl.SSL_VERIFYPEER, 0)
    c.setopt(c.WRITEDATA, buffer)
    c.setopt(c.HTTPHEADER,[\'Content-Type: application/json\'])

    myUrl = wpUrl.format(page)
    #print(myUrl)
    c.setopt(c.URL,myUrl)
    c.perform()

    page+= 1
    if buffer != None:
        myData = json.loads(buffer.getvalue())
        for foo in myData:
            print("MediaID ={}, caption = {}, alt_text={}".format(foo["id"], foo["caption"], foo[\'alt_text\']))
            #print(foo)
        if len(myData) <= 0:
            bContinue = False
    else:
        bContinue = False
    c.close()

######################################################
# Create A Post
######################################################
from wordpress_xmlrpc import Client, WordPressPost
from wordpress_xmlrpc.methods.posts import NewPost

#authenticate
wp_url = "https://info-qa.cloudquant.com/xmlrpc.php"
wp_username = "My_User_ID_on_WP"
wp_password = "My_PWD_on_WP"


wp = Client(wp_url, wp_username, wp_password)

#post and activate new post
post = WordPressPost()
post.title = \'3 Post\'
post.content = \'<h1>heading 1</h1>Tayloe was here<br><small>here too!</small><p>New para.\'
post.post_status = \'draft\'
post.thumbnail = 50  # The ID of the image determined in Step 1
post.slug = "123abc"
post.terms_names = {
  \'post_tag\': [\'MyTag\'],
  \'category\': [\'Category\']
}
wp.call(NewPost(post))

我发现了我的问题，只是把它传给别人，以防有人用谷歌搜索到这个。

你需要像这样传递图像id

{缩略图：123}

将123替换为您的图像id。

我想所有额外的数据都会自动填充。