Ls LDP Container using LDFlex

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1

I’m trying to play with LDFlex, but I failed to list items inside a folder.

const data = ldflex['https://linonetwo.solid.authing.cn/public/tiddlywiki/main']
console.log('data', await data['http://www.w3.org/ns/ldp#contains'])
// logs undefined

So how to read what it contains?

2

I tried this:

        const data = ldflex[containerURI]
        const items = await data['ldp:contains'].sparql

which gaves me the sparql:

SELECT ?contains WHERE {
  <https://linonetwo.solid.authing.cn/public/tiddlywiki/main> <http://www.w3.org/ns/ldp#contains> ?contains.
}

I tried it on the following ttl file on the playground https://ci.mines-stetienne.fr/sparql-generate/playground.html :

@prefix : <#>.
@prefix m: <>.
@prefix ldp: <http://www.w3.org/ns/ldp#>.
@prefix terms: <http://purl.org/dc/terms/>.
@prefix XML: <http://www.w3.org/2001/XMLSchema#>.
@prefix st: <http://www.w3.org/ns/posix/stat#>.
@prefix tur: <http://www.w3.org/ns/iana/media-types/text/turtle#>.

m:
    a ldp:BasicContainer, ldp:Container;
    terms:modified "2019-12-24T03:53:21Z"^^XML:dateTime;
    ldp:contains
        <%2524%253A%252FStoryList>, <%2524%253A%252FStoryList.metadata>,
        <Draft%2520of%2520'New%2520Tiddler'%2520by%2520https%253A%252F%252Flinonetwo.solid.authing.cn%252Fprofile%252Fcard%2523me.metadata>,
        m:Test, <Test.metadata>, m:Test123, <Test123.metadata>;
    st:mtime 1577159601.427;
    st:size 4096.

With no result.
And I found that, if I change

@prefix : <#>.
@prefix m: <>.

to

@prefix : <#>.
@prefix m: <https://linonetwo.solid.authing.cn/public/tiddlywiki/main>.

then I’m able to get the result.

So the problem is <>, it should be <https://linonetwo.solid.authing.cn/public/tiddlywiki/main> to let LDFlex work.
Maybe ldflex can add a function that enables me to replace <> with <https://linonetwo.solid.authing.cn/public/tiddlywiki/main> ?

3

I think it’s the missing trailing slash. This works for me in ldflex playground:

data[https://linonetwo.solid.authing.cn/public/tiddlywiki/main/][http://www.w3.org/ns/ldp#contains]

4

Thank you @aveltens ! That is very tricky!

When trust an origin, we should not add slash: I should trust http://localhost:8080, not http://localhost:8080/

Slash problems are so tricky!

5

Yes indeed. It’s helpful to understand the several parts oft an URI. While the origin only consists oft scheme+host+port a ressource is identified with a full URI including path, query and fragment. But even then trailing slashes are easily overlooked…

6

Just to note, we are going to improve the trusted applications in the data browsers by automatically remove the trailing slash when people accidentally add it - https://github.com/solid/mashlib/issues/74

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