Problem: UCS@school Import Error: "None is not of type 'object'"

[fdavid]

TLDR

• Error: None is not of type 'object'
• Cause: Missing "classes" section in the configuration file.
• Fix: Add "classes": {} to your JSON file.
• Verification: Use jq to check syntax and structure.

By including the mandatory classes block, you ensure the configuration passes schema validation and the import job can proceed successfully.

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Problem

When configuring user imports in UCS@school, you may encounter the following error during a test run:

An error occurred while preparing the import job: Schema validation failed for configuration file '/var/lib/ucs-school-import/jobs/2025/102/3_user_import.json': None is not of type 'object'

This error usually indicates that your JSON configuration file is missing a required section.

---

Example

The configuration file (3_user_import.json) looked like this:

{
    "csv": {
        "mapping": {
            "Vorname": "firstname",
            "Nachname": "lastname",
            "Klassen": "school_classes",
            "Schule": "school",
            "Merkmal": "record_uid"
        }
    },
    "scheme": {
        "username": {
            "default": "<school><:umlauts><firstname>[0:3]<lastname>[0:3]<:lower>[COUNTER2]"
        },
        "email": "<:umlauts><firstname>.<lastname>[COUNTER2]@<school>.domain.de",
        "record_uid": "<record_uid>"
    },
    "password_length": 8
}

At first glance, this file looks correct and valid JSON. However, UCS@school performs schema validation on the configuration. In this schema, a section named classes is mandatory — even if you don’t use it.

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Root Cause

The error is triggered because the section "classes" is missing from the configuration.
The UCS@school validation schema expects this block to always exist as an object. If it’s missing, it is treated internally as None, leading to the error message:

None is not of type 'object'

---

Solution

Add the classes section to your configuration file. Even if you don’t need to configure classes, an empty object will satisfy the schema:

{
    "csv": {
        "mapping": {
            "Vorname": "firstname",
            "Nachname": "lastname",
            "Klassen": "school_classes",
            "Schule": "school",
            "Merkmal": "record_uid"
        }
    },
    "scheme": {
        "username": {
            "default": "<school><:umlauts><firstname>[0:3]<lastname>[0:3]<:lower>[COUNTER2]"
        },
        "email": "<:umlauts><firstname>.<lastname>[COUNTER2]@<school>.domain.de",
        "record_uid": "<record_uid>"
    },
    "classes": {},
    "password_length": 8
}

---

Verification

To confirm the syntax and structure of your JSON file, you can use the tool jq:

apt install jq
jq . /var/lib/ucs-school-import/jobs/2025/102/3_user_import.json

If the file is valid JSON, jq will pretty-print it. If not, it will display an error pointing to the invalid part.