为什么PPTX的缩略图在MS Graph Search中不起作用

如何解决为什么PPTX的缩略图在MS Graph Search中不起作用

我正在使用Microsoft Graph资源管理器在Sharepoint中搜索PPTX文件：

https://graph.microsoft.com/v1.0/sites/MYSITE.sharepoint.com/drive/root/search(q = 'term AND .pptx')?$expand=thumbnails

这很好用，并返回结果，包括缩略图的网址，例如：

    "value": [
        {
         [...],"thumbnails": [
                {
                    "id": "0","large": {
                        "height": 800,"url": "https://westeurope1-mediap.svc.ms/transform/thumbnail?provider=spo&inputFormat=pptx&cs=ZGU4YmM4YjUtZDlmOS00OGIxLWE4YWQtYjc0OGRhNzI1MDY0fFNQTw&docid=https%3A%2F%2Fveodin2%2Esharepoint%2Ecom%2F%5Fapi%2Fv2%2E0%2Fdrives%2Fb%21ZZLBnC7JSUiDFsO07HLwwZiU%5F3PZL3hOreOxO%2D7%2D6OUVoo3IebmnSLCtR%5FGar3MR%2Fitems%2F01D33FTF2VJGLOTD3PG5HJEJTWDA5HQN4T%3Faccess%5Ftoken%3DeyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9%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%2EZ%2D3mJ6UrcrCyvXB0fOJpZgArYqHAShQDVhSb6XaoJY4%26prooftoken%3DeyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiIsIng1dCI6InhYbFQwSUp4MlZCVEJFeVFMdGtFOFY2ZkhwZyJ9%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%2EpHVBmvjFcARCcygYv4ll6zuayGQRDChsHI7%5FNSEic%5F0U8PB9mmrIqE2cw%5FlNLKxVQ0pLlbV%2Dx64K6SlxwC1jSRzUNlsEAuEdMKNxlnKVND81OZoGYFMm3vMjHnFmXXIrv7CRc93NeFcByYwU%2DnqHg%2D2ETvyaUmdQjqdoBXtCVo80Jybj0Tek3f8qnz%2DncexDzAks6nBlgjhEqRi9hTBPWblnhvDZVoeQYb26MCU2pwyhWRe3ziH6M4WuEqT4NaOU9v3UNtK87rG%5Ffg%2DL5DVbWlYb2vywt1jNKFYs535WPHAFOS7h3ior4qHP471xTr4s%5Frgu1%2Dz0o0Ep9S%2DZXaj5kw%26version%3DPublished&width=800&height=800&cb=63627410891","width": 800
                    },[...]
            }
            ]
        }
    ]
}

但是返回的URL不起作用，但会引发错误：

{"error":{

  "code": "generalException","message": "Error from Office Service. Url=https://pptcs.officeapps.live.com/document/export/thumbnail HttpCode=NotFound cert=subject:;thumbprint: ResponseHeaders=Connection: close\r\nDate: Fri,11 Sep 2020 12:25:31 GMT\r\nServer: Microsoft-IIS/10.0\r\nX-Powered-By: ASP.NET\r\n","innererror": {

    "code": "OfficeConversion_ConverterInternal"

  }

}}

在PDF上正常工作。

（在搜索商品ID之后）也明确查询缩略图URL，就像`https://graph.microsoft.com/v1.0/sites/MYSITE.sharepoint.com/drive/items/{item- id} /缩略图