ducky/subscriptions
2015-09-27
Parent:f1a22fc2321d
ducky/subscriptions/postgres.go
Add comments, move ChangingSystemProperties to the api package. Add comments to all our exported types and variables in subscription.go, both to make golint happy and because it's good to have comments. Move the subscriptions.ChangingSystemProperties helper to api.changingSystemProperties, because it returns API-specific strings and there's no real reason it has to be in the subscriptions package--everything it needs to work on is exported.
| paddy@1 | 1 package subscriptions |
| paddy@1 | 2 |
| paddy@1 | 3 import ( |
| paddy@1 | 4 "database/sql" |
| paddy@1 | 5 ) |
| paddy@1 | 6 |
| paddy@1 | 7 // NewPostgres returns a usable Postgres instance, if and only |
| paddy@1 | 8 // if error is nil. If error is not nil, the returned Postgres |
| paddy@1 | 9 // instance should not be used. |
| paddy@1 | 10 func NewPostgres(conn string) (Postgres, error) { |
| paddy@1 | 11 db, err := sql.Open("postgres", conn) |
| paddy@1 | 12 if err != nil { |
| paddy@1 | 13 return Postgres{}, err |
| paddy@1 | 14 } |
| paddy@1 | 15 return Postgres{db}, nil |
| paddy@1 | 16 } |
| paddy@1 | 17 |
| paddy@1 | 18 // Postgres represents a thin wrapper around *sql.DB, so we can |
| paddy@1 | 19 // inherit its methods but also define our own (so we can fulfill |
| paddy@1 | 20 // our subscriptionStore interface on Postgres). Note that the |
| paddy@1 | 21 // value of a Postgres variable contains a _pointer_ to an sql.DB |
| paddy@1 | 22 // pool of connections, so it's not necessary to use the address of |
| paddy@1 | 23 // the Postgres variable itself (though there shouldn't be any harm |
| paddy@1 | 24 // in doing so). |
| paddy@1 | 25 type Postgres struct { |
| paddy@1 | 26 *sql.DB |
| paddy@1 | 27 } |