Shopify API（Python）文件上传出现Processing Error原因排查

尝试通过Python调用Shopify API将图片上传至店铺Files板块，代码参考公开实现编写。代码运行无报错，fileCreate接口返回成功数据：

{'data': {'fileCreate': {'files': [{'alt': 'alt-tag'}], 'userErrors': []}}, 'extensions': {'cost': {'requestedQueryCost': 20, 'actualQueryCost': 20, 'throttleStatus': {'maximumAvailable': 1000.0, 'currentlyAvailable': 980, 'restoreRate': 50.0}}}}

但店铺Files页面显示“1 upload failed -- processing error”，请求排查代码问题。代码如下：

import requests
import os

# Set up Shopify API credentials
shopify_store = 'url-goes-here.myshopify.com' # 实际URL已替换
access_token = 'token-goes-here' # 实际token已替换

# Read the image file
image_path = r'C:\the-actual-filepath-is-here\API-TEST-1.jpg'  # Replace with the actual path to your image file
with open(image_path, 'rb') as file:
    image_data = file.read()

# Create staged upload
staged_upload_url = f"https://{shopify_store}/admin/api/2023-04/graphql.json"
staged_upload_query = '''
mutation stagedUploadsCreate($input: [StagedUploadInput!]!) {
  stagedUploadsCreate(input: $input) {
    stagedTargets {
      resourceUrl
      url
      parameters {
        name
        value
      }
    }
    userErrors {
      field
      message
    }
  }
}
'''
staged_upload_variables = {
    "input": [
        {
            "filename": "API-TEST-1.jpg",
            "httpMethod": "POST",
            "mimeType": "image/jpeg",
            "resource": "FILE"
        }
    ]
}

response = requests.post(
    staged_upload_url,
    json={"query": staged_upload_query, "variables": staged_upload_variables},
    headers={"X-Shopify-Access-Token": access_token}
)

data = response.json()
staged_targets = data['data']['stagedUploadsCreate']['stagedTargets']
target = staged_targets[0]
params = target['parameters']
url = target['url']
resource_url = target['resourceUrl']

# Post image data to the staged target
form_data = {
    "file": image_data
}
headers = {
    param['name']: param['value'] for param in params  # Fix the headers assignment
}
headers["Content-Length"] = str(len(image_data))

response = requests.post(url, files=form_data, headers=headers)  # Use 'files' parameter instead of 'data'

# Create the file in Shopify using the resource URL
create_file_url = f"https://{shopify_store}/admin/api/2023-04/graphql.json"
create_file_query = '''
mutation fileCreate($files: [FileCreateInput!]!) {
  fileCreate(files: $files) {
    files {
      alt
    }
    userErrors {
      field
      message
    }
  }
}
'''
create_file_variables = {
    "files": [
        {
            "alt": "alt-tag",
            "contentType": "IMAGE",
            "originalSource": resource_url
        }
    ]
}

response = requests.post(
    create_file_url,
    json={"query": create_file_query, "variables": create_file_variables},
    headers={"X-Shopify-Access-Token": access_token}
)

data = response.json()
files = data['data']['fileCreate']['files']
alt = files[0]['alt']

出现这个问题的核心原因是上传到临时存储（staged target）时的请求格式错误，具体问题和修复如下：

1. 错误处理StagedUpload返回的Parameters #

Shopify返回的parameters里，一部分是请求头参数，另一部分是表单字段参数，不能全部塞进请求头：

• 以Content-开头的参数属于请求头
• 其他参数（比如key、policy、signature等）属于表单字段

2. 手动设置Content-Length导致冲突 #

使用requests.post的files参数时，requests会自动计算并设置Content-Length，手动设置会导致实际上传内容长度与声明的不匹配，引发处理错误。

3. 文件上传未指定文件名和MIME类型 #

直接传二进制数据时，需要明确指定文件名和MIME类型，让Shopify正确识别文件格式。

修复后的代码（替换上传到staged target的部分） #

# Post image data to the staged target
# 分离header参数和表单参数
headers = {}
form_fields = {}
for param in params:
    if param['name'].startswith('Content-'):
        headers[param['name']] = param['value']
    else:
        form_fields[param['name']] = param['value']

# 构造files参数，指定文件名和MIME类型
files = {
    'file': ('API-TEST-1.jpg', image_data, 'image/jpeg')
}

# 发送请求，不需要手动设置Content-Length
response = requests.post(url, files=files, data=form_fields, headers=headers)

# 检查临时上传是否成功
if response.status_code not in [200, 201]:
    print(f"临时上传失败: {response.text}")
    exit()

额外建议 #

• 调用stagedUploadsCreate后，检查userErrors是否为空，提前排查错误
• 临时上传后，检查响应状态码和内容，确认文件已成功上传到临时存储

内容的提问来源于stack exchange，提问作者king_anton