Issue
I am currently developing a web app which uses the Facebook Graph API.
What I would like to achieve is to get all posts of a user.
However, this is not that easy since I have to paginate the results.
At the moment I am struggeling with promises.
What I try to achieve is to fill an array with the post objects.
Therefore I use promises and recursion which does not work as expected.
My code currently looks as follows:
// Here I retrieve the user with his or her posts,
// just the first 25 due to pagination
if (accessToken) {
return new Promise(resolve => {
FB.api('/me?fields=id,name,posts&access_token=' + accessToken, response => {
this.get('currentUser').set('content', response);
resolve()
})
})
}
// Returns all posts of a given user
function getAllPostsOfUser(posts, postsArr) {
// Process each post of the current pagination level
for (var post of posts.data) {
// Only store meaningful posts
if (post !== undefined && post.message !== undefined) {
postsArr.push(post)
}
}
// Further posts are retrievalable via paging.next which is an url
if (posts.data.length !== 0 && posts.paging.next !== undefined) {
FB.api(posts.paging.next, response => {
getAllPostsOfUser(response, postsArr)
resolve()
})
}
return postsArr
}
var posts = getAllPostsOfUser(this.get('currentUser').content.posts, [])
// I want to use all the posts here
console.log(posts)
The problem I have is that I want to use the posts where the console.log is placed but when I log the posts array a lot of posts are missing.
I am sure that I did something wrong with the promises but I do not know what.
I would be glad if anyone could guide me to a solution.
Thank you in advance.
Solution
Try this:
function getAllPosts() {
return new Promise((resolve, reject) => {
let postsArr = [];
function recursiveAPICall(apiURL) {
FB.api(apiURL, (response) => {
if (response && response.data) {
//add response to posts array (merge arrays), check if there is more data via paging
postsArr = postsArr.concat(response.data);
if (response.paging && response.paging.next) {
recursiveAPICall(response.paging.next);
} else {
resolve(postsArr);
}
} else {
reject();
}
});
}
recursiveAPICall("/me/posts?fields=message&limit=100");
});
}
getAllPosts()
.then((response) => {
console.log(response);
})
.catch((e) => {
console.log(e);
});
Not tested, just a quick example I came up with. It returns a promise and uses a recursive function to get all entries. BTW, you don't need to add the Access Token. If you are logged in, the SDK will use it internally.
Answered By - andyrandy Answer Checked By - Robin (PHPFixing Admin)
Posts
