db: functional tests fail if run twice against same DB

[ericchiang]

I think this has something to do with the migrations table not being dropped.

[ericchiang]

Some steps to reproduce

Window 1:

$ rkt version
rkt version 0.15.0
appc version 0.7.4
$ sudo rkt run --interactive --net=host quay.io/coreos/postgres
...

Window 2:

$ ./git-version 
09d8d8423cac115cfaf22ffde89c62e46a8f6cc9
$ DEX_TEST_DSN=postgres://postgres@localhost/postgres?sslmode=disable ./test
Running tests...
ok      github.com/coreos/dex/connector 0.040s  coverage: 22.7% of statements
ok      github.com/coreos/dex/db    0.068s  coverage: 6.4% of statements
ok      github.com/coreos/dex/integration   3.191s  coverage: 0.0% of statements
ok      github.com/coreos/dex/pkg/crypto    0.008s  coverage: 75.7% of statements
ok      github.com/coreos/dex/pkg/flag  0.002s  coverage: 97.5% of statements
ok      github.com/coreos/dex/pkg/http  0.010s  coverage: 72.1% of statements
ok      github.com/coreos/dex/pkg/net   0.031s  coverage: 71.4% of statements
ok      github.com/coreos/dex/pkg/time  0.007s  coverage: 100.0% of statements
ok      github.com/coreos/dex/pkg/html  0.004s  coverage: 78.9% of statements
ok      github.com/coreos/dex/functional/repo   19.941s coverage: 60.0% of statements
ok      github.com/coreos/dex/server    3.730s  coverage: 48.3% of statements
ok      github.com/coreos/dex/session   0.011s  coverage: 75.3% of statements
ok      github.com/coreos/dex/user  2.625s  coverage: 37.4% of statements
ok      github.com/coreos/dex/user/api  0.007s  coverage: 82.4% of statements
ok      github.com/coreos/dex/user/manager  0.505s  coverage: 68.1% of statements
ok      github.com/coreos/dex/email 0.004s  coverage: 42.8% of statements
Checking gofmt...
Checking govet...
Success
$ DEX_TEST_DSN=postgres://postgres@localhost/postgres?sslmode=disable ./test
Running tests...
ok      github.com/coreos/dex/connector 0.027s  coverage: 22.7% of statements
ERROR: Failed purging : <nil>
ERROR: Failed purging : <nil>
ERROR: Failed purging : <nil>
ERROR: Failed purging : <nil>
ERROR: Failed purging : <nil>
--- FAIL: TestGetPlannedMigrations (0.09s)
    migrate_test.go:40: expected non-empty migrations
FAIL
coverage: 6.4% of statements
FAIL    github.com/coreos/dex/db    0.103s
ok      github.com/coreos/dex/integration   2.922s  coverage: 0.0% of statements
ok      github.com/coreos/dex/pkg/crypto    0.012s  coverage: 75.7% of statements
ok      github.com/coreos/dex/pkg/flag  0.014s  coverage: 97.5% of statements
ok      github.com/coreos/dex/pkg/http  0.007s  coverage: 72.1% of statements
ok      github.com/coreos/dex/pkg/net   0.012s  coverage: 71.4% of statements
ok      github.com/coreos/dex/pkg/time  0.002s  coverage: 100.0% of statements
ok      github.com/coreos/dex/pkg/html  0.004s  coverage: 78.9% of statements
ok      github.com/coreos/dex/functional/repo   19.521s coverage: 60.0% of statements
ok      github.com/coreos/dex/server    3.493s  coverage: 48.3% of statements
ok      github.com/coreos/dex/session   0.003s  coverage: 75.3% of statements
ok      github.com/coreos/dex/user  2.262s  coverage: 37.4% of statements
ok      github.com/coreos/dex/user/api  0.005s  coverage: 82.4% of statements
ok      github.com/coreos/dex/user/manager  0.519s  coverage: 68.1% of statements
ok      github.com/coreos/dex/email 0.005s  coverage: 42.8% of statements
$

Restarting the Postgres database fixes the error.

[ericchiang]

closed in #339