Six Degrees - Spotify

An API that uses data collected from the Spotify API to find a connection between two artists.
The Project is inspired by the Small-world Experiment aka Six degrees of separation.

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How it works

Two artists are directly connected if both of them collaborated on the same song. However, most of the time this isn't the case, so the quest becomes to find a third artist that collaborated with the first two in separated occasions.

If such artist does not exist, this process is repeated, adding connections until a path between the two first artists is found, or it is verified that there is no connection between them. A max number of connection can also be specified.

This search is made possible by using the Spotify Web API data from artists and tracks and importing them to a graph database (Neo4J).

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Examples

1. Michael Jackson and Johnny Cash

• Michael Jackson played Say Say Say with Paul McCartney

• Paul McCartney played New Moon Over Jamaica with Johnny Cash

There is a second degree connection between Michael Jackson and Johnny Cash.

2. Lady Gaga and The Strokes

• Lady Gaga played Jewels N' Drugs with T.I.

• T.I. played How I Feel (feat. Eric Bellinger & Killer Mike) with Killer Mike

• Killer Mike played pulling the pin (feat. Mavis Staples & Josh Homme) with Josh Homme

• Josh Homme played Mercy Mercy Me with The Strokes

There is a fourth degree connection between Lady Gaga and The Strokes.

3. Iron Maiden and BTS

Sadly, there is no connection between Iron Maiden and BTS.

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Request

Name	Method	Description
/connection	GET	Searches for a connection between two artists. If there is a path connecting both, returns an array of the nodes that make out the path. The nodes in the array always alternate between artists and tracks.

Search Parameters

Name	Type	Required / Optional	Description
start	string	required	Spotify ID of the first artist in the connection.
end	string	required	Spotify ID of the last artist in the connection.
exclude_artist	string	optional	List of artists ID's to exclude from connection search. Comma Separated.
exclude_track	string	optional	List of tracks ID's to exclude from connection search. Comma Separated.
include_artist	string	optional	List of artists ID's to include in the connection search. Comma Separated.
include_track	string	optional	List of tracks ID's to include in the connection search. Comma Separated.
limit	number	optional	Max number of nodes between start and end.

Return

/connection/?start=3fMbdgg4jU18AjLCKBhRSm&end=6kACVPfCOnqzgfEF5ryl0x

[
    {
        "image": "https://i.scdn.co/image/ab6761610000e5eba2a0b9e3448c1e702de9dc90",
        "followers": 23980363,
        "name": "Michael Jackson",
        "link": "https://open.spotify.com/artist/3fMbdgg4jU18AjLCKBhRSm",
        "id": "3fMbdgg4jU18AjLCKBhRSm",
        "type": "artist"
    },
    {
        "image": "https://i.scdn.co/image/ab67616d0000b27392ed057542e2c0d3b9647c07",
        "link": "https://open.spotify.com/track/1db0gbTSKdRQum8VlbNkiO",
        "name": "Say Say Say - Remastered 2015",
        "albumId": "6zlKkX99NhLW8IRy77bYmb",
        "id": "1db0gbTSKdRQum8VlbNkiO",
        "type": "track"
    },
    {
        "image": "https://i.scdn.co/image/ab6761610000e5eb03bf2fe26e397122faa3d323",
        "followers": 4110946,
        "name": "Paul McCartney",
        "link": "https://open.spotify.com/artist/4STHEaNw4mPZ2tzheohgXB",
        "id": "4STHEaNw4mPZ2tzheohgXB",
        "type": "artist"
    },
    {
        "image": "https://i.scdn.co/image/ab67616d0000b273ade431b5fdd43d4617eccdcf",
        "name": "New Moon Over Jamaica",
        "link": "https://open.spotify.com/track/3R2xNYnwseHB77A9CIHata",
        "albumId": "2ey9jImi467qEu67fvW1kP",
        "id": "3R2xNYnwseHB77A9CIHata",
        "type": "track"
    },
    {
        "image": "https://i.scdn.co/image/ab6761610000e5eb152cf48cf9541c7061570857",
        "followers": 5468648,
        "name": "Johnny Cash",
        "link": "https://open.spotify.com/artist/6kACVPfCOnqzgfEF5ryl0x",
        "id": "6kACVPfCOnqzgfEF5ryl0x",
        "type": "artist"
    }
]