Blob store upload returns HTTP 405 error when using POST instead of PUT – Lucidworks

Issue

When attempting to upload a file to the Fusion blob store using the POST method, the request fails with the following error:

{
  "type": "RESTError",
  "httpStatusCode": 405,
  "error": "ERR-0003",
  "message": "A web application error occurred",
  "details": "HTTP 405 Method Not Allowed",
  "localizedMessage": "HTTP 405 Method Not Allowed",
  "httpStatusMessage": "Method Not Allowed"
}

Even after assigning POST and PUT permissions in the relevant API roles, the upload continues to fail.

Diagnosis

This issue typically occurs when:

The upload attempt uses the POST HTTP method instead of the required PUT method.
The blob is uploaded to the global namespace (/api/blobs/...) but is expected to appear in an app-scoped UI (e.g., /api/apps/<appname>/blobs/...).
The blob appears to upload successfully (returns 200 OK), but is not visible in the blob store UI under a specific app scope.

To confirm:

Review the HTTP response code.
Check the Allow response header to verify supported methods.
Attempt to retrieve the uploaded file using the /manifest endpoint to verify its existence.

Environment

Fusion 5.x (Managed Fusion, Lucidworks-hosted)

Applies to deployments using the blob store service via app-scoped or global API endpoints.

Cause

The Fusion blob store service does not accept POST for uploads. Instead, it requires the use of the PUT method with the file as a binary body and a Content-Type header.

Additionally, uploads to the global blob namespace (/api/blobs/...) will not appear in the blob store UI of a specific app (e.g., entsearch), which expects blobs to be uploaded under the app-scoped path (/api/apps/<appname>/blobs/...).

Resolution

Use the PUT method to upload files and ensure uploads are scoped correctly based on UI or API expectations.

Upload using PUT with correct content headers

Replace {{host}} and {{appname}} with your deployment-specific values.

Global scope (not visible in app UI):

curl -T FOND_BRETT_TEST.csv \
  -H "Content-Type: text/csv" \
  "https://{{host}}/api/blobs/FOND_BRETT_TEST?resourceType=file"

App-scoped (UI-visible):

curl -T FOND_BRETT_TEST.csv \
  -H "Content-Type: text/csv" \
  "https://{{host}}/api/apps/{{appname}}/blobs/FOND_BRETT_TEST?resourceType=file"

Verify blob visibility using the manifest endpoint

App-scoped check:

curl -X GET \
  "https://{{host}}/api/apps/{{appname}}/blobs/FOND_BRETT_TEST/manifest"

Global scope check (if not using app-scoped path):

curl -X GET \
  "https://{{host}}/api/blobs/FOND_BRETT_TEST/manifest"

Update API roles if necessary

Ensure the following permissions are assigned to the appropriate roles:

For global scope uploads:
- PUT:/blobs/**
- GET:/blobs/**
For app-scoped uploads:
- PUT:/apps/{{appname}}/blobs/**
- GET:/apps/{{appname}}/blobs/**

Once the correct method and path are used, and role permissions are in place, files should upload successfully and appear in the appropriate blob store UI.