Neo4J Support

.gitignore

@@ -6,3 +6,4 @@ cli/migrate
 .godoc.pid
 vendor/
 .vscode/
+.idea/

.travis.yml

@@ -36,6 +36,11 @@ before_install:
   # Install golangci-lint
   - curl -sfL https://install.goreleaser.com/github.com/golangci/golangci-lint.sh | sh -s -- -b $(go env GOPATH)/bin v1.22.2
   - echo "TRAVIS_GO_VERSION=${TRAVIS_GO_VERSION}"
+  # Install seabolt for Neo4j
+  - sudo apt-get install -y libssl1.0.0
+  - wget https://github.com/neo4j-drivers/seabolt/releases/download/v1.7.4/seabolt-1.7.4-Linux-ubuntu-$(lsb_release -rs).deb
+  - sudo dpkg -i seabolt-1.7.4-Linux-ubuntu-$(lsb_release -rs).deb
+  - rm seabolt-1.7.4-Linux-ubuntu-$(lsb_release -rs).deb
 
 install:
   - go get github.com/mattn/goveralls

Dockerfile

@@ -3,12 +3,20 @@ ARG VERSION
 
 RUN apk add --no-cache git gcc musl-dev
 
+# dependencies for neo4j
+RUN apk add --update --no-cache ca-certificates cmake make g++ libressl-dev openssl-dev git curl pkgconfig
+
+# build seabolt for neo4j driver
+RUN git clone -b 1.7 https://github.com/neo4j-drivers/seabolt.git /seabolt
+WORKDIR /seabolt/build
+RUN cmake -D CMAKE_BUILD_TYPE=Release -D CMAKE_INSTALL_LIBDIR=lib .. && cmake --build . --target install
+
 WORKDIR /go/src/github.com/golang-migrate/migrate
 
 COPY . ./
 
 ENV GO111MODULE=on
-ENV DATABASES="postgres mysql redshift cassandra spanner cockroachdb clickhouse mongodb sqlserver firebird"
+ENV DATABASES="postgres mysql redshift cassandra spanner cockroachdb clickhouse mongodb sqlserver firebird neo4j"
 ENV SOURCES="file go_bindata github github_ee aws_s3 google_cloud_storage godoc_vfs gitlab"
 
 RUN go build -a -o build/migrate.linux-386 -ldflags="-s -w -X main.Version=${VERSION}" -tags "$DATABASES $SOURCES" ./cmd/migrate

Makefile

@@ -1,5 +1,6 @@
 SOURCE ?= file go_bindata github github_ee aws_s3 google_cloud_storage godoc_vfs gitlab
 DATABASE ?= postgres mysql redshift cassandra spanner cockroachdb clickhouse mongodb sqlserver firebird
+DATABASE_TEST ?= $(DATABASE) sqlite neo4j
 VERSION ?= $(shell git describe --tags 2>/dev/null | cut -c 2-)
 TEST_FLAGS ?=
 REPO_OWNER ?= $(shell cd .. && basename "$$(pwd)")
@@ -8,11 +9,11 @@ COVERAGE_DIR ?= .coverage
 
 build-cli: clean
 	-mkdir ./cli/build
-	cd ./cmd/migrate && CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -a -o ../../cli/build/migrate.linux-amd64 -ldflags='-X main.Version=$(VERSION) -extldflags "-static"' -tags '$(DATABASE) $(SOURCE)' .
-	cd ./cmd/migrate && CGO_ENABLED=0 GOOS=linux GOARCH=arm GOARM=7 go build -a -o ../../cli/build/migrate.linux-armv7 -ldflags='-X main.Version=$(VERSION) -extldflags "-static"' -tags '$(DATABASE) $(SOURCE)' .
-	cd ./cmd/migrate && CGO_ENABLED=0 GOOS=linux GOARCH=arm64 go build -a -o ../../cli/build/migrate.linux-arm64 -ldflags='-X main.Version=$(VERSION) -extldflags "-static"' -tags '$(DATABASE) $(SOURCE)' .
-	cd ./cmd/migrate && CGO_ENABLED=0 GOOS=darwin GOARCH=amd64 go build -a -o ../../cli/build/migrate.darwin-amd64 -ldflags='-X main.Version=$(VERSION) -extldflags "-static"' -tags '$(DATABASE) $(SOURCE)' .
-	cd ./cmd/migrate && CGO_ENABLED=0 GOOS=windows GOARCH=amd64 go build -a -o ../../cli/build/migrate.windows-amd64.exe -ldflags='-X main.Version=$(VERSION) -extldflags "-static"' -tags '$(DATABASE) $(SOURCE)' .
+# 	cd ./cmd/migrate && CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -a -o ../../cli/build/migrate.linux-amd64 -ldflags='-X main.Version=$(VERSION) -extldflags "-static"' -tags '$(DATABASE) $(SOURCE)' .
+# 	cd ./cmd/migrate && CGO_ENABLED=0 GOOS=linux GOARCH=arm GOARM=7 go build -a -o ../../cli/build/migrate.linux-armv7 -ldflags='-X main.Version=$(VERSION) -extldflags "-static"' -tags '$(DATABASE) $(SOURCE)' .
+# 	cd ./cmd/migrate && CGO_ENABLED=0 GOOS=linux GOARCH=arm64 go build -a -o ../../cli/build/migrate.linux-arm64 -ldflags='-X main.Version=$(VERSION) -extldflags "-static"' -tags '$(DATABASE) $(SOURCE)' .
+	cd ./cmd/migrate && CGO_ENABLED=1 GOOS=darwin GOARCH=amd64 go build -a -o ../../cli/build/migrate.darwin-amd64 -ldflags='-X main.Version=$(VERSION) -extldflags "-static"' -tags '$(DATABASE) $(SOURCE)' .
+# 	cd ./cmd/migrate && CGO_ENABLED=1 GOOS=windows GOARCH=amd64 go build -a -o ../../cli/build/migrate.windows-amd64.exe -ldflags='-X main.Version=$(VERSION) -extldflags "-static"' -tags '$(DATABASE) $(SOURCE)' .
 	cd ./cli/build && find . -name 'migrate*' | xargs -I{} tar czf {}.tar.gz {}
 	cd ./cli/build && shasum -a 256 * > sha256sum.txt
 	cat ./cli/build/sha256sum.txt
@@ -34,7 +35,7 @@ test:
 
 test-with-flags:
 	@echo SOURCE: $(SOURCE)
-	@echo DATABASE: $(DATABASE)
+	@echo DATABASE_TEST: $(DATABASE_TEST)
 
 	@go test $(TEST_FLAGS) ./...
 

README.md

@@ -29,7 +29,7 @@ Database drivers run migrations. [Add a new database?](database/driver.go)
 * [Cassandra](database/cassandra)
 * [SQLite](database/sqlite3) ([todo #165](https://github.com/mattes/migrate/issues/165))
 * [MySQL/ MariaDB](database/mysql)
-* [Neo4j](database/neo4j) ([todo #167](https://github.com/mattes/migrate/issues/167))
+* [Neo4j](database/neo4j)
 * [MongoDB](database/mongodb)
 * [CrateDB](database/crate) ([todo #170](https://github.com/mattes/migrate/issues/170))
 * [Shell](database/shell) ([todo #171](https://github.com/mattes/migrate/issues/171))

database/driver.go

@@ -13,7 +13,8 @@ import (
 )
 
 var (
-	ErrLocked = fmt.Errorf("can't acquire lock")
+	ErrLocked    = fmt.Errorf("can't acquire lock")
+	ErrNotLocked = fmt.Errorf("can't unlock, as not currently locked")
 )
 
 const NilVersion int = -1
@@ -33,7 +34,7 @@ var drivers = make(map[string]Driver)
 //      All other functions are tested by tests in database/testing.
 //      Saves you some time and makes sure all database drivers behave the same way.
 //   5. Call Register in init().
-//   6. Create a migrate/cli/build_<driver-name>.go file
+//   6. Create a internal/cli/build_<driver-name>.go file
 //   7. Add driver name in 'DATABASE' variable in Makefile
 //
 // Guidelines:
@@ -61,7 +62,7 @@ type Driver interface {
 	// all migrations have been run.
 	Unlock() error
 
-	// Run applies a migration to the database. migration is garantueed to be not nil.
+	// Run applies a migration to the database. migration is guaranteed to be not nil.
 	Run(migration io.Reader) error
 
 	// SetVersion saves version and dirty state.

database/neo4j/README.md

@@ -0,0 +1,11 @@
+# neo4j
+
+`neo4j://user:password@host:port/`
+
+| URL Query  | WithInstance Config | Description |
+|------------|---------------------|-------------|
+| `user` | Contained within `AuthConfig` | The user to sign in as |
+| `password` | Contained within `AuthConfig` | The user's password | 
+| `host` | | The host to connect to. Values that start with / are for unix domain sockets. (default is localhost) |
+| `port` | | The port to bind to. (default is 7687) |
+|  | `MigrationsLabel` | Name of the migrations node label |

database/neo4j/TUTORIAL.md

@@ -0,0 +1,97 @@
+## Create migrations
+Let's create nodes called `Users`:
+```
+migrate create -ext cypher -dir db/migrations -seq create_user_nodes
+```
+If there were no errors, we should have two files available under `db/migrations` folder:
+- 000001_create_user_nodes.down.cypher
+- 000001_create_user_nodes.up.cypher
+
+Note the `cypher` extension that we provided.
+
+In the `.up.cypher` file let's create the table:
+```
+CREATE (u1:User {name: "Peter"})
+CREATE (u2:User {name: "Paul"})
+CREATE (u3:User {name: "Mary"})
+```
+And in the `.down.sql` let's delete it:
+```
+MATCH (u:User) WHERE u.name IN ["Peter", "Paul", "Mary"] DELETE u
+```
+Ideally your migrations should be idempotent. You can read more about idempotency in [getting started](GETTING_STARTED.md#create-migrations)
+
+## Run migrations
+```
+migrate -database ${NEO4J_URL} -path db/migrations up
+```
+Let's check if the table was created properly by running `bin/cypher-shell -u neo4j -p password`, then `neo4j> MATCH (u:User)`
+The output you are supposed to see:
+```
++-----------------------------------------------------------------+
+| u                                                               |
++-----------------------------------------------------------------+
+| (:User {name: "Peter")                                          |
+| (:User {name: "Paul")                                           |
+| (:User {name: "Mary")                                           |
++-----------------------------------------------------------------+
+```
+Great! Now let's check if running reverse migration also works:
+```
+migrate -database ${NEO4J_URL} -path db/migrations down
+```
+Make sure to check if your database changed as expected in this case as well.
+
+## Database transactions
+
+To show database transactions usage, let's create another set of migrations by running:
+```
+migrate create -ext cypher -dir db/migrations -seq add_mood_to_users
+```
+Again, it should create for us two migrations files:
+- 000002_add_mood_to_users.down.cypher
+- 000002_add_mood_to_users.up.cypher
+
+In Neo4j, when we want our queries to be done in a transaction, we need to wrap it with `:BEGIN` and `:COMMIT` commands.
+Migration up:
+```
+:BEGIN
+
+MATCH (u:User)
+SET u.mood = "Cheery"
+
+:COMMIT
+```
+Migration down:
+```
+:BEGIN
+
+MATCH (u:User)
+SET u.mood = null
+
+:COMMIT
+```
+
+## Optional: Run migrations within your Go app
+Here is a very simple app running migrations for the above configuration:
+```
+import (
+	"log"
+
+	"github.com/golang-migrate/migrate/v4"
+	_ "github.com/golang-migrate/migrate/v4/database/neo4j"
+	_ "github.com/golang-migrate/migrate/v4/source/file"
+)
+
+func main() {
+	m, err := migrate.New(
+		"file://db/migrations",
+		"neo4j://neo4j:password@localhost:7687/")
+	if err != nil {
+		log.Fatal(err)
+	}
+	if err := m.Up(); err != nil {
+		log.Fatal(err)
+	}
+}
+```

database/neo4j/examples/migrations/1578421040_create_movies_constraint.down.cypher

@@ -0,0 +1 @@
+DROP CONSTRAINT ON (m:Movie) ASSERT m.Name IS UNIQUE

database/neo4j/examples/migrations/1578421040_create_movies_constraint.up.cypher

@@ -0,0 +1 @@
+CREATE CONSTRAINT ON (m:Movie) ASSERT m.Name IS UNIQUE

database/neo4j/examples/migrations/1578421725_create_movies.down.cypher

@@ -0,0 +1,2 @@
+MATCH (m:Movie)
+DELETE m

database/neo4j/examples/migrations/1578421725_create_movies.up.cypher

@@ -0,0 +1,2 @@
+CREATE (:Movie {name: "Footloose"})
+CREATE (:Movie {name: "Ghost"})