Parts of YAML file do not work when db name is "off"

[CharlesNepote]

I guess this issue is not very important and probably rare.

To reproduce:

• create and populate a db named off.db
• in the yaml file, add any kind of information below databases:\n off:
• the data are not taken into account (because "off" is interpreted as "false")

YAML file:

title: Some title
description_html: |-
  <p>This is an experiment.</p>
databases:
  off:
    tables:
      products_from_owners:
        title: products_from_owners*
        description_html: |-
          <p>Description</p>

The result for http://xxxx.xxx/-/metadata gives:

{
    "title": "Some title",
    "description_html": "<p>This is an experiment.</p>",
    "databases": {
        "false": {
            "tables": {
                "products_from_owners": {
                    "title": "products_from_owners*",
                    "description_html": "<p>Description</p>"
                }
            }
        }
    }
}

=> see the "false" instead of "off".

[simonw]

Oh that's a classic YAML problem, I hadn't realized it would affect Datasette like this!

You should be able to fix it by quoting the off key like this:

title: Some title
description_html: |-
  <p>This is an experiment.</p>
databases:
  "off":
    tables:
      products_from_owners:
        title: products_from_owners*
        description_html: |-
          <p>Description</p>

[simonw]

There's a thread about this here, but it doesn't have any workaround that look to me like they would be worth applying: https://stackoverflow.com/questions/36463531/pyyaml-automatically-converting-certain-keys-to-boolean-values

[simonw]

It's a nasty gotcha though. I'm inclined to add validation to Datasette that fails to start the server with an error if you attempt to start it with metadata that accidentally has a boolean where a database name is expected.

[simonw]

Here's a very old issue that suggests validating metadata:

• Validate metadata.json on startup #260