FacebookLikesCollection: Build a collection of Facebook likes to posts and comments
In theclue/facebook.S4: Access to Facebook API V2 via a Set of S4 Classes

Description Usage Arguments Details Value Nesting fields Valid sources Author(s) See Also Examples

Connect to Facebook Graph API, get information from a list of likes to public posts or comments and build a FacebookLikesCollection-class instance.

FacebookLikesCollection(id, token = NULL, parameters = list(),
  fields = c("id", "name", "profile_type"),
  n = getOption("facebook.maxitems"), metadata = FALSE,
  .progress = create_progress_bar(), stop.condition = function(x) {    
  FALSE })

`id`	A character vector or a comma-delimited string of IDs or an existing Facebook Collection of any of the supported types (see below).
`token`	Either a temporary access token created at https://developers.facebook.com/tools/explorer or the OAuth token created with `fbOAuth`. If token `NULL` and `id` is a collection, use the token of the source collection. Otherwise, no query is performed to the Facebook Graph API and an empty collection is returned.
`parameters`	A list of parameters to be added to the Facebook Graph API query. For more information on the accepted parameters, see: https://developers.facebook.com/docs/graph-api/using-graph-api.
`fields`	A character vector with the fields to get for each `id`. If no value for a given field is found, it will be set to `NULL`.
`n`	If `id` is an iterable collection, then `n` is the maximum number of likes to be pulled for each element of the source collection in `id`. It can be set to `Inf` to pull out any available public like and assumes the default value from the value of `facebook.maxitems` global option if missing. If `id` is not a collection or cannot be iterated, the parameter is ignored.
`metadata`	If set to `TRUE`, the metadata for each ID is pulled with the data and the `type` slot is fed accordingly. Please note that setting this to `TRUE` could considerably slow down the execution time, as more queries are needed.
`.progress`	progress_bar object as defined in the plyr package. By default the `none` progress bar is used, which prints nothing to the console. See create_progress_bar for details.
`stop.condition`	anonymous function that is executed for each element of the collection, passed to the function as a list called 'x'. If the function returns `TRUE`, the execution of the query will end up at the end of the current page (even if more pages of data are available). By default, this function will always return `FALSE`.

FacebookLikesCollection is the constructor for the FacebookLikesCollection-class. It returns data about likes to posts or comments but doesn't return the comments or posts themselves.

Since Facebook doesn't provide a key for a single like, the ID slot for this kind of collection doesn't uniquely identify a like on Facebook. The id (the user who put the like) coupled with the parent (the place where she put the like) identifies a unique key for the like.

As a consequence, you cannot build a likes collection starting from atomic IDs, but you must pass an instance of a Facebook Posts Collection or a Facebook Comments Collection built using the construction FacebookPostsCollection or FacebookCommentsCollection as id parameter.

A collection of likes in a FacebookLikesCollection-class object.

Due to the network-graph nature of Facebook data model, you can specify fields details for each field nesting .fields() clauses.

For example, if you need only id and source for the cover field, this is valid among others: cover.fields(id,source).

Following the same philosophy, if you need only id and name for the from node you can use from.fields(id,name).

Instead of a character vector, one of these collections can also be passed as parameter in id:

FacebookPostsCollection-class will build a collection with all the likes to the posts of the source collection
FacebookCommentsCollection-class will build a collection with all the likes to the comments of the source collection
FacebookUsersCollection-class will build a collection with the posts written on the walls of the users in the source collection.
FacebookPhotosCollection-class will build a collection with the likes to the photos in the source collection. The author of the photo may grant the user_photos to the current application to perform this action.
FacebookVideosCollection-class will build a collection with the likes to the videos in the source collection. The author of the photo may grant the user_videos to the current application to perform this action.

Gabriele Baldassarre https://gabrielebaldassarre.com

FacebookCommentsCollection, FacebookPostsCollection, facebook.object.likes, fbOAuth

Other Facebook Collection Constructors: FacebookAlbumsCollection, FacebookCommentsCollection, FacebookConversationsCollection, FacebookEventsCollection, FacebookGroupsCollection, FacebookMessagesCollection, FacebookPagesCollection, FacebookPhotosCollection, FacebookPostsCollection, FacebookReactionsCollection, FacebookUsersCollection, FacebookVideosCollection

## Not run: 
## See examples for fbOAuth to know how token was created.
 load("fb_oauth")
 
## Getting information about two example Facebook Pages
 fb.pages <- FacebookPagesCollection(id = c("9thcirclegames",
                                            "NathanNeverSergioBonelliEditore"),
                                     token = fb_oauth)
 
## Pull the latest 10 posts from each page in a pages collection
 fb.posts <- FacebookPostscollection(id = fb.pages, token = fb_oauth, n = 10)
 
## Pull all the likes from each element of the posts collection
fb.posts.likes <- FacebookLikesCollection(fb.posts, fb_token, n = Inf)
 
## Pull all the available comments from each post of the post collection
 fb.comments <- FacebookPostscollection(id = fb.posts, token = fb_oauth, n = Inf)
 
## Pull all the likes from each element of the comments collections
 fb.comments.likes <- FacebookLikesCollection(id = fb.comments, token = fb_oauth, n = Inf)  
   
## Convert the collection to a data frame
fb.posts.likes.df <- as.data.frame(fb.posts.likes)

# The same as before in a more compact fashion using the pipe operator
# chaining from a Pages then to a Posts Collection and finally building a Likes Collection
fb.posts.likes.pipe <- 
 FacebookPagesCollection(id = c("9thcirclegames",
                                "NathanNeverSergioBonelliEditore"),
                         token = fb_oauth) %>%
     FacebookPostscollection(n = 10) %>%
     FacebookLikesCollection(n = Inf)

## End(Not run)