Manage Friends using Solid

Build a Solid App
1

Hi! I’m currently in a work team and we are developing an application using Solid. We want to add a friendship system that allows the user to introduce the webID of one of his friends and the friend will be added in Solid. We are using the libraries @inrupt/solid-client and “@inrupt/vocab-common-rdf”

Until now I´m trying to store the webIDs as foaf:knows in the profile/card section of the user. The code with which i’m working is the following:

export async function addFriend(webID:string, friend:Friend): Promise<{ error: boolean, errorMessage: string }> {
    let profile = webID.split("#")[0]; //just in case there is extra information in the url
    // get the dataset from the url
    let dataSet = await getSolidDataset(profile, {fetch: fetch});  
  
    let dataSetThing = getThing(dataSet, webID) as Thing;

    try {
      let existsFriend = getUrlAll(dataSetThing, FOAF.knows)
      if (existsFriend.some((url) => url === friend.webID)){
        return{error:true,errorMessage:"You are already friends with this user!"}
      }
      else{
        // We create the friend
      let newFriend = buildThing(dataSetThing)
      .addUrl(FOAF.knows, friend.webID as string)
      .build();

      // insert friend in dataset
      dataSet = setThing(dataSet, dataSetThing);
      dataSet = await saveSolidDatasetAt(webID, dataSet, {fetch: fetch})
      return{error:false,errorMessage:""}
      }
    } catch (error){
      return{error:true,errorMessage:"Not a valid webId!"}
    }
}

This code does not break but no webIDs are added when looking at the source code of the profile/card.

Does anybody know where do I have the problem or another way in which this can be solved?
If you want to take a look, here is our GitHub repository: GitHub - Arquisoft/lomap_en2a: LoMap Software architecture group en2a course 2022_23
This piece of code is in the filter-patri branch.

Thank you very much in advance!

2

On the first look it seems fine. Have you checked what it actually stores? e.g. console.log(dataSet) before you save it and then also take a look at the network requests in the browser dev tools to see what is actually stored at the saveSolidDatasetAt call.

3

Oh, and you never use the newFriend variable?

4

We made it work! We used the browser to debug the flow of the eecution and apparently we were not grabbing the :me section of the profile card. But now is working.

Thank you very much! :grinning:

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