Apply migrations when tink-server boots (#296)

## Description

It will be nice to have the tink-server capable of applying migrations
if necessary. The idea to self-apply migrations will may look unusual
but it is an easy way to distribute software capable of migrating
database schema without having to run any external procedures.
## Why is this needed

Fixes: #295 

## How Has This Been Tested?

```console
$ docker run -d -it -e  POSTGRES_PASSWORD=tinkerbell -e POSTGRES_USER=tinkerbell -p 5432:5432 postgres
# PGPASSWORD=tinkerbell PGUSER=tinkerbell PGSSLMODE=disable PACKET_VERSION=v1 PACKET_ENV=ga ROLLBAR_TOKEN=ignored go run cmd/tink-server/main.go
{"level":"info","ts":1600772721.3009,"caller":"tink-server/main.go:30","msg":"starting version devel","service":"github.com/tinkerbell/tink"}
migrations  1
records  0
{"level":"info","ts":1600772721.309925,"caller":"tink-server/main.go:54","msg":"Your database schema is not up to date. Please apply migrations running tink-server with env var ONLY_MIGRATION set.","service":"github.com/tinkerbell/tink"}
{"level":"info","ts":1600772721.310011,"caller":"metrics/metrics.go:58","msg":"initializing label values","service":"github.com/tinkerbell/tink"}
```

As suggested you should run tink-server with ONLY_MIGRATION=true

```
$ ONLY_MIGRATION=true PGPASSWORD=tinkerbell PGUSER=tinkerbell PGSSLMODE=disable PACKET_VERSION=v1 PACKET_ENV=ga ROLLBAR_TOKEN=ignored go run cmd/tink-server/main.go
{"level":"info","ts":1600772853.779405,"caller":"tink-server/main.go:30","msg":"starting version devel","service":"github.com/tinkerbell/tink"}
{"level":"info","ts":1600772853.779805,"caller":"tink-server/main.go:40","msg":"Applying migrations. This process will end when migrations will take place.","service":"github.com/tinkerbell/tink"}
{"level":"info","ts":1600772853.819854,"caller":"tink-server/main.go:45","msg":"Running migrations if necessary","service":"github.com/tinkerbell/tink","num_applied_migrations":1}
```

## How are existing users impacted? What migration steps/scripts do we need?

They are not impacted by this change.

## Checklist:

I have:

- [ ] updated the documentation and/or roadmap (if required)
- [ ] added unit or e2e tests
- [ ] provided instructions on how to upgrade

cmd/tink-server/main.go

@@ -7,6 +7,7 @@ import (
 	"syscall"
 
 	"github.com/packethost/pkg/log"
+	"github.com/tinkerbell/tink/db"
 	rpcServer "github.com/tinkerbell/tink/grpc-server"
 	httpServer "github.com/tinkerbell/tink/http-server"
 )
@@ -20,7 +21,6 @@ var (
 
 func main() {
 	log, err := log.Init("github.com/tinkerbell/tink")
-
 	if err != nil {
 		panic(err)
 	}
@@ -32,7 +32,30 @@ func main() {
 	errCh := make(chan error, 2)
 	facility := os.Getenv("FACILITY")
 
-	cert, modT := rpcServer.SetupGRPC(ctx, logger, facility, errCh)
+	tinkDB := db.Connect(logger)
+
+	_, onlyMigration := os.LookupEnv("ONLY_MIGRATION")
+	if onlyMigration {
+		logger.Info("Applying migrations. This process will end when migrations will take place.")
+		numAppliedMigrations, err := tinkDB.Migrate()
+		if err != nil {
+			log.Fatal(err)
+			panic(err)
+		}
+		log.With("num_applied_migrations", numAppliedMigrations).Info("Migrations applied successfully")
+		os.Exit(0)
+	}
+
+	numAvailableMigrations, err := tinkDB.CheckRequiredMigrations()
+	if err != nil {
+		log.Fatal(err)
+		panic(err)
+	}
+	if numAvailableMigrations != 0 {
+		log.Info("Your database schema is not up to date. Please apply migrations running tink-server with env var ONLY_MIGRATION set.")
+	}
+
+	cert, modT := rpcServer.SetupGRPC(ctx, logger, facility, tinkDB, errCh)
 	httpServer.SetupHTTP(ctx, logger, cert, modT, errCh)
 
 	sigs := make(chan os.Signal, 1)
@@ -49,12 +72,12 @@ func main() {
 	// wait for grpc server to shutdown
 	err = <-errCh
 	if err != nil {
-		logger.Error(err)
+		log.Fatal(err)
 		panic(err)
 	}
 	err = <-errCh
 	if err != nil {
-		logger.Error(err)
+		log.Fatal(err)
 		panic(err)
 	}
 }

db/db.go

@@ -10,6 +10,8 @@ import (
 	"github.com/lib/pq"
 	"github.com/packethost/pkg/log"
 	"github.com/pkg/errors"
+	migrate "github.com/rubenv/sql-migrate"
+	"github.com/tinkerbell/tink/db/migration"
 	pb "github.com/tinkerbell/tink/protos/workflow"
 )
 
@@ -73,6 +75,19 @@ func Connect(lg log.Logger) *TinkDB {
 	return &TinkDB{instance: db}
 }
 
+func (t *TinkDB) Migrate() (int, error) {
+	return migrate.Exec(t.instance, "postgres", migration.GetMigrations(), migrate.Up)
+}
+
+func (t *TinkDB) CheckRequiredMigrations() (int, error) {
+	migrations := migration.GetMigrations().Migrations
+	records, err := migrate.GetMigrationRecords(t.instance, "postgres")
+	if err != nil {
+		return 0, err
+	}
+	return len(migrations) - len(records), nil
+}
+
 // Error returns the underlying cause for error
 func Error(err error) *pq.Error {
 	if pqErr, ok := errors.Cause(err).(*pq.Error); ok {

db/migration/202009171251-init-database.go

@@ -0,0 +1,87 @@
+package migration
+
+import migrate "github.com/rubenv/sql-migrate"
+
+func Get202009171251() *migrate.Migration {
+	return &migrate.Migration{
+		Id: "202009171251-init-database",
+		Up: []string{`
+SET ROLE tinkerbell;
+SELECT 'CREATE DATABASE tinkerbell' WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'tinkerbell');
+
+CREATE TABLE IF NOT EXISTS hardware (
+	id UUID UNIQUE
+	, inserted_at TIMESTAMPTZ
+	, deleted_at TIMESTAMPTZ
+	, data JSONB
+);
+
+CREATE INDEX IF NOT EXISTS idx_id ON hardware (id);
+CREATE INDEX IF NOT EXISTS idx_deleted_at ON hardware (deleted_at NULLS FIRST);
+CREATE INDEX IF NOT EXISTS idxgin_type ON hardware USING GIN (data JSONB_PATH_OPS);
+
+CREATE TABLE IF NOT EXISTS template (
+        id UUID UNIQUE NOT NULL
+        , name VARCHAR(200) UNIQUE NOT NULL
+        , created_at TIMESTAMPTZ
+        , updated_at TIMESTAMPTZ
+        , deleted_at TIMESTAMPTZ
+        , data BYTEA
+
+        CONSTRAINT CK_name CHECK (name ~ '^[a-zA-Z0-9_-]*$')
+);
+
+CREATE INDEX IF NOT EXISTS idx_tid ON template (id);
+CREATE INDEX IF NOT EXISTS idx_tdeleted_at ON template (deleted_at NULLS FIRST);
+
+CREATE TABLE IF NOT EXISTS workflow (
+	id UUID UNIQUE NOT NULL
+	, template UUID NOT NULL
+	, devices JSONB NOT NULL
+	, created_at TIMESTAMPTZ
+	, updated_at TIMESTAMPTZ
+	, deleted_at TIMESTAMPTZ
+);
+
+CREATE INDEX IF NOT EXISTS idx_wid ON workflow (id);
+CREATE INDEX IF NOT EXISTS idx_wdeleted_at ON workflow (deleted_at NULLS FIRST);
+
+CREATE TABLE IF NOT EXISTS workflow_state (
+        workflow_id UUID UNIQUE NOT NULL
+        , current_task_name VARCHAR(200)
+        , current_action_name VARCHAR(200)
+        , current_action_state SMALLINT
+        , current_worker VARCHAR(200)
+        , action_list JSONB
+        , current_action_index int
+        , total_number_of_actions INT
+);
+
+CREATE INDEX IF NOT EXISTS idx_wfid ON workflow_state (workflow_id);
+
+CREATE TABLE IF NOT EXISTS workflow_event (
+        workflow_id UUID NOT NULL
+        , worker_id UUID  NOT NULL
+        , task_name VARCHAR(200)
+        , action_name VARCHAR(200)
+        , execution_time int
+	, message VARCHAR(200)
+	, status SMALLINT
+        , created_at TIMESTAMPTZ
+);
+
+CREATE INDEX IF NOT EXISTS idx_event ON workflow_event (created_at);
+
+CREATE TABLE IF NOT EXISTS workflow_worker_map (
+        workflow_id UUID NOT NULL
+        , worker_id UUID NOT NULL
+);
+
+CREATE TABLE IF NOT EXISTS workflow_data (
+        workflow_id UUID NOT NULL
+        , version INT
+        , metadata JSONB
+        , data JSONB
+);`},
+	}
+}

db/migration/migration.go

@@ -0,0 +1,11 @@
+package migration
+
+import migrate "github.com/rubenv/sql-migrate"
+
+func GetMigrations() *migrate.MemoryMigrationSource {
+	return &migrate.MemoryMigrationSource{
+		Migrations: []*migrate.Migration{
+			Get202009171251(),
+		},
+	}
+}

deploy/docker-compose.yml

@@ -34,11 +34,9 @@ services:
     image: postgres:10-alpine
     restart: unless-stopped
     environment:
-      POSTGRES_DB: tinkerbell
       POSTGRES_PASSWORD: tinkerbell
       POSTGRES_USER: tinkerbell
     volumes:
-      - ./db/tinkerbell-init.sql:/docker-entrypoint-initdb.d/tinkerbell-init.sql:ro
       - postgres_data:/var/lib/postgresql/data:rw
     ports:
       - 5432:5432

go.mod

@@ -13,8 +13,6 @@ require (
 	github.com/go-openapi/strfmt v0.19.3 // indirect
 	github.com/golang/protobuf v1.4.2
 	github.com/google/uuid v1.1.2
-	github.com/gorilla/context v1.1.1 // indirect
-	github.com/gorilla/mux v1.6.2 // indirect
 	github.com/grpc-ecosystem/go-grpc-prometheus v1.2.0
 	github.com/grpc-ecosystem/grpc-gateway v1.14.6
 	github.com/jedib0t/go-pretty v4.3.0+incompatible
@@ -26,18 +24,18 @@ require (
 	github.com/opencontainers/image-spec v1.0.1 // indirect
 	github.com/packethost/pkg v0.0.0-20200903155310-0433e0605550
 	github.com/pkg/errors v0.8.1
-	github.com/prometheus/client_golang v1.1.0
+	github.com/prometheus/client_golang v1.3.0
+	github.com/rubenv/sql-migrate v0.0.0-20200616145509-8d140a17f351
 	github.com/sirupsen/logrus v1.4.2
 	github.com/spf13/cobra v1.0.0
 	github.com/spf13/viper v1.4.0
-	github.com/stretchr/testify v1.3.0
+	github.com/stretchr/testify v1.4.0
 	go.mongodb.org/mongo-driver v1.1.2 // indirect
 	golang.org/x/net v0.0.0-20200324143707-d3edc9973b7e // indirect
 	golang.org/x/sys v0.0.0-20200331124033-c3d80250170d // indirect
-	golang.org/x/time v0.0.0-20191024005414-555d28b269f0 // indirect
 	google.golang.org/genproto v0.0.0-20200526211855-cb27e3aa2013
 	google.golang.org/grpc v1.29.1
 	google.golang.org/protobuf v1.25.0
-	gopkg.in/yaml.v2 v2.2.3
+	gopkg.in/yaml.v2 v2.2.5
 	gotest.tools v2.2.0+incompatible // indirect
 )