JSON Schema - metadata.title/subtitle, harmonization with ReadiumWebPubManifest?

[danielweck]

The main difference (besides the looser type definition) is that OPDS subtitles allow arrays:

https://github.com/opds-community/drafts/blob/4d82fb9a64f35a174a5f205c23ba623ec010d5ec/schema/feed-metadata.schema.json#L22

    "subtitle": {
      "type": [
        "string",
        "array",
        "object"
      ]
},

versus:

https://github.com/readium/webpub-manifest/blob/0976680e25852b8a4c4802a052ba750ab3e89284/schema/metadata.schema.json#L33

    "subtitle": {
      "anyOf": [
        {
          "type": "string"
        },
        {
          "description": "The language in a language map must be a valid BCP 47 tag.",
          "type": "object",
          "patternProperties": {
            "^((?<grandfathered>(en-GB-oed|i-ami|i-bnn|i-default|i-enochian|i-hak|i-klingon|i-lux|i-mingo|i-navajo|i-pwn|i-tao|i-tay|i-tsu|sgn-BE-FR|sgn-BE-NL|sgn-CH-DE)|(art-lojban|cel-gaulish|no-bok|no-nyn|zh-guoyu|zh-hakka|zh-min|zh-min-nan|zh-xiang))|((?<language>([A-Za-z]{2,3}(-(?<extlang>[A-Za-z]{3}(-[A-Za-z]{3}){0,2}))?)|[A-Za-z]{4}|[A-Za-z]{5,8})(-(?<script>[A-Za-z]{4}))?(-(?<region>[A-Za-z]{2}|[0-9]{3}))?(-(?<variant>[A-Za-z0-9]{5,8}|[0-9][A-Za-z0-9]{3}))*(-(?<extension>[0-9A-WY-Za-wy-z](-[A-Za-z0-9]{2,8})+))*(-(?<privateUse>x(-[A-Za-z0-9]{1,8})+))?)|(?<privateUse2>x(-[A-Za-z0-9]{1,8})+))$": {
              "type": "string"
            }
          },
          "additionalProperties": false,
          "minProperties": 1
        }
      ]
},

[danielweck]

Exact same issue with title:

https://github.com/opds-community/drafts/blob/4d82fb9a64f35a174a5f205c23ba623ec010d5ec/schema/feed-metadata.schema.json#L15

https://github.com/readium/webpub-manifest/blob/0976680e25852b8a4c4802a052ba750ab3e89284/schema/metadata.schema.json#L15

[danielweck]

Related issue: https://github.com/opds-community/drafts/issues/25

[HadrienGardeur]

They're a little undefined in the current draft as well, so their current expression in the JSON Schema is consistent with that.

It's not clear if we need all that complexity for the metadata of a feed, or if we need a subtitle either.

[acuna-public]

It's so sad that new draft don't supports Readium manifest which is more user-friendly for develop it :(

[HadrienGardeur]

@acuna-public since OPDS 2.0 is very much based on Readium, it's not clear what you mean by that.

[acuna-public]

@HadrienGardeur I've created an issue here. Please compare the draft and docs, for example links section became as

"links": [
    {"rel": "self", "href": "http://example.com/opds", "type": "application/opds+json"}
  ]

in the docs, but at the draft which link present at the end of the docs as an example it became

"links": {
    "description": "Feed-level links such as search or pagination",
    "type": "array",
    "items": {
         "$ref": "https://readium.org/webpub-manifest/schema/link.schema.json"
    },
    "uniqueItems": true,
    "contains": {
    "properties": {
            "rel": {
                "anyOf": [
                    {
                        "type": "string",
                        "const": "self"
                    },
                    {
                        "type": "array",
                        "contains": {
                            "const": "self"
                        }
                    }
                ]
            }
        },
        "required": [
            "rel"
        ]
    }
},

Or I've missed something?

[HadrienGardeur]

Basically this schema means:

• that the definition of the Link Object is based on Readium: https://readium.org/webpub-manifest/schema/link.schema.json
• that each Link Object must be unique (which can't be moved to the Link Object schema)
• that we must have at least one Link Object where the rel value is set to self (that's a requirement for an OPDS Feed)

Could you explain why this is problematic?

[acuna-public]

I believe that it means anywhere, but I don't see it at the docs. I think you don't want to users asked you about any of the item so you create the docs, isn't it? :) So I've implemented any what described in docs only for cosily support it in future.