将字符向量套回到原始数据帧

Question

I am using the lapply function to call Spotify's API. I have a column of albumids and I want to retrieve the track names from each albumid. The way I did this was by separating the albumid into a character vector and then running and using the lapply function to call each value in the character vector. The problem with this is that I cannot put this back into the original dataframe.

Here is an example:

I have a dataframe that looks like this:

df
               Artist ID Artist Name     Album Name              Album IDs
1 5lDUVqxXYEOAf12p0N2kVT Jared Dylan       We Can't 16PsUE4xzqxIvmNIlwQzmK
2 5lDUVqxXYEOAf12p0N2kVT Jared Dylan Love Is a Game 4NYvHAON7Zo4KC2BMn5rlI
3 5lDUVqxXYEOAf12p0N2kVT Jared Dylan Enjoy the View 5AipKv8MFdERzk9xxEN3OK
4 5lDUVqxXYEOAf12p0N2kVT Jared Dylan  Luna Loves Me 3u4XXqFOiltaNXyKAhkzGN
5 5lDUVqxXYEOAf12p0N2kVT Jared Dylan       Symphony 0x5PQLx5tFNEpfhQnXhU8t
6 5lDUVqxXYEOAf12p0N2kVT Jared Dylan    In Panic EP 02mIkCCHDYzJWDzh0DDs5g

I then created a character vector from the Album IDs column like below:

spotify<-df$`Album IDs`

Then I created a function to retrieve the trackids, artistid, artist name, and track names for each Album ID:

get.tracks <- function(spotify){
  albumTracksURL <- paste("https://api.spotify.com/v1/albums/", spotify, "/tracks?limit=50", sep="")
  getTracks <- GET(albumTracksURL, add_headers(Authorization = HeaderValue))
  albumTracks <- jsonlite::fromJSON(toJSON(content(getTracks)))

  ids <- data.frame(matrix(unlist(albumTracks$items$id), 
                       nrow=albumTracks$total, byrow=T),stringsAsFactors=FALSE)

  names <- data.frame(matrix(unlist(albumTracks$items$name), 
                         nrow=albumTracks$total, byrow=T),stringsAsFactors=FALSE)
  artists<-albumTracks$items$artists
  artists1<-do.call(rbind, lapply(artists, function(x) do.call(cbind, lapply(x[c('id', 'name')], toString))))

  result <- cbind(ids, names, artists1)

  colnames(result) <- c("ID", "NAME", "ARTIST ID", "ARTIST NAME")

  return(result)
}

df <- lapply(spotify, get.tracks)

result <- do.call(rbind, df)
result_final<-result

Here is what this result looks like:

result_final

                       ID             NAME              ARTIST ID ARTIST NAME
1  2YjOdgzqMIokknjOLS9ksc         We Can't 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
2  5zSJepyr4V94yICIwhEBNK   Love Is a Game 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
3  4o7qeWp4eQflplPVtoiJhM   Enjoy the View 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
4  4LtSJDlu8UvM4hNlJsSj31    Luna Loves Me 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
5  4a91BtkczDVQdgKWUiwuyy         Symphony 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
6  36XHtu9IgcoUEylPDYfPpr         In Panic 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
7  6LEgJv1ClgvjDzmr7WG4hE         Mistakes 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
8  5GxzbBprsHtk05qQeATGZR Ready, Set, Stun 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
9  1PHIPb4HyaatPqQfw2t288   Drive Me Crazy 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
10 6M9hgVrs4oj4YCFdXod1u4  Always Faithful 5lDUVqxXYEOAf12p0N2kVT Jared Dylan

The problem with this is that I cannot relate it back to the original dataframe since there is no primary key (albumid). I think I need to do a for-loop or a different apply function on the original df instead of separating it out as a character vector but I do not know how to do that. The goal is to make the final result look like this below:

                Artist.ID Artist.Name     Album.Name              Album.IDs                     ID             NAME              ARTIST.ID ARTIST.NAME
1  5lDUVqxXYEOAf12p0N2kVT Jared Dylan       We Can't 16PsUE4xzqxIvmNIlwQzmK 2YjOdgzqMIokknjOLS9ksc         We Can't 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
2  5lDUVqxXYEOAf12p0N2kVT Jared Dylan Love Is a Game 4NYvHAON7Zo4KC2BMn5rlI 5zSJepyr4V94yICIwhEBNK   Love Is a Game 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
3  5lDUVqxXYEOAf12p0N2kVT Jared Dylan Enjoy the View 5AipKv8MFdERzk9xxEN3OK 4o7qeWp4eQflplPVtoiJhM   Enjoy the View 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
4  5lDUVqxXYEOAf12p0N2kVT Jared Dylan  Luna Loves Me 3u4XXqFOiltaNXyKAhkzGN 4LtSJDlu8UvM4hNlJsSj31    Luna Loves Me 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
5  5lDUVqxXYEOAf12p0N2kVT Jared Dylan       Symphony 0x5PQLx5tFNEpfhQnXhU8t 4a91BtkczDVQdgKWUiwuyy         Symphony 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
6  5lDUVqxXYEOAf12p0N2kVT Jared Dylan    In Panic EP 02mIkCCHDYzJWDzh0DDs5g 36XHtu9IgcoUEylPDYfPpr         In Panic 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
7  5lDUVqxXYEOAf12p0N2kVT Jared Dylan    In Panic EP 02mIkCCHDYzJWDzh0DDs5g 6LEgJv1ClgvjDzmr7WG4hE         Mistakes 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
8  5lDUVqxXYEOAf12p0N2kVT Jared Dylan    In Panic EP 02mIkCCHDYzJWDzh0DDs5g 5GxzbBprsHtk05qQeATGZR Ready, Set, Stun 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
9  5lDUVqxXYEOAf12p0N2kVT Jared Dylan    In Panic EP 02mIkCCHDYzJWDzh0DDs5g 1PHIPb4HyaatPqQfw2t288   Drive Me Crazy 5lDUVqxXYEOAf12p0N2kVT Jared Dylan
10 5lDUVqxXYEOAf12p0N2kVT Jared Dylan    In Panic EP 02mIkCCHDYzJWDzh0DDs5g 6M9hgVrs4oj4YCFdXod1u4  Always Faithful 5lDUVqxXYEOAf12p0N2kVT Jared Dylan

Answer 1

At the end of your function get.tracks add a column for album.

...
colnames(result) <- c("ID", "NAME", "ARTIST ID", "ARTIST NAME")
result$`Album IDs` <- spotify
return(result)

Then you can merge back into the original using Album IDs as the key.