mirror of
https://github.com/twitter/the-algorithm.git
synced 2024-12-23 06:15:32 +00:00
63 lines
1.5 KiB
Markdown
63 lines
1.5 KiB
Markdown
|
# Common thrift types
|
||
|
|
|
||
|
|
GFS uses several thrift datastructures which are common to multiple queries. They are listed below.
|
||
|
|
|
||
|
|
## EdgeType
|
||
|
|
|
||
|
|
`EdgeType` is a thrift enum which specifies which edge types to query for the graph.
|
||
|
|
|
||
|
|
```thrift
|
||
|
|
enum EdgeType {
|
||
|
|
FOLLOWING,
|
||
|
|
FOLLOWED_BY,
|
||
|
|
FAVORITE,
|
||
|
|
FAVORITED_BY,
|
||
|
|
RETWEET,
|
||
|
|
RETWEETED_BY,
|
||
|
|
REPLY,
|
||
|
|
REPLYED_BY,
|
||
|
|
MENTION,
|
||
|
|
MENTIONED_BY,
|
||
|
|
MUTUAL_FOLLOW,
|
||
|
|
SIMILAR_TO, // more edge types (like block, report, etc.) can be supported later.
|
||
|
|
RESERVED_12,
|
||
|
|
RESERVED_13,
|
||
|
|
RESERVED_14,
|
||
|
|
RESERVED_15,
|
||
|
|
RESERVED_16,
|
||
|
|
RESERVED_17,
|
||
|
|
RESERVED_18,
|
||
|
|
RESERVED_19,
|
||
|
|
RESERVED_20
|
||
|
|
}
|
||
|
|
```
|
||
|
|
|
||
|
|
For an example of how this is used, consider the `GetNeighbors` query. If we set the `edgeType` field
|
||
|
|
of the `GfsNeighborsRequest`, the response will contain all the users that the specified user follows.
|
||
|
|
If, on the other hand, we set `edgeType` to be `FollowedBy` it will return all the users who are
|
||
|
|
followed by the specified user.
|
||
|
|
|
||
|
|
## FeatureType
|
||
|
|
|
||
|
|
`FeatureType` is a thrift struct which is used in queries which require two edge types.
|
||
|
|
|
||
|
|
```thrift
|
||
|
|
struct FeatureType {
|
||
|
|
1: required EdgeType leftEdgeType // edge type from source user
|
||
|
|
2: required EdgeType rightEdgeType // edge type from candidate user
|
||
|
|
}(persisted="true")
|
||
|
|
```
|
||
|
|
|
||
|
|
## UserWithScore
|
||
|
|
|
||
|
|
The candidate generation queries return lists of candidates together with a computed score for the
|
||
|
|
relevant feature. `UserWithScore` is a thrift struct which bundles together a candidate's ID with
|
||
|
|
the score.
|
||
|
|
|
||
|
|
```thrift
|
||
|
|
struct UserWithScore {
|
||
|
|
1: required i64 userId
|
||
|
|
2: required double score
|
||
|
|
}
|
||
|
|
```
|