Neo4j GraphQL 库（graphql--neo4j-graphql-2.5.5.tar.gz）

# neo-push Example blog site built with Neo4j GraphQL & React.js. This application showcases features of Neo4j GraphQL such as; 1. Nested Mutations 2. @auth directive 3. OGM(Object Graph Mapper) There are only two custom resolvers in the server; sign up plus sign in. The lack of custom logic is showcasing how quickly developers can build, both powerful and secure, applications ontop of Neo4j. Its worth nothing this entire application contains zero 'raw' cypher. All interaction's with the database are done through the generated GraphQL Schema via either the OGM or Apollo Server.   **Diagram from https://arrows.app/** ```graphql type User { id: ID! @id email: String! password: String! createdBlogs: [Blog] @relationship(type: "HAS_BLOG", direction: OUT) authorsBlogs: [Blog] @relationship(type: "CAN_POST", direction: OUT) password: String! @private createdAt: DateTime @timestamp(operations: [CREATE]) updatedAt: DateTime @timestamp(operations: [UPDATE]) } type Blog { id: ID! @id name: String! creator: User @relationship(type: "HAS_BLOG", direction: IN) authors: [User] @relationship(type: "CAN_POST", direction: IN) posts: [Post] @relationship(type: "HAS_POST", direction: OUT) createdAt: DateTime @timestamp(operations: [CREATE]) updatedAt: DateTime @timestamp(operations: [UPDATE]) } type Post { id: ID! @id title: String! content: String! blog: Blog @relationship(type: "HAS_POST", direction: IN) comments: [Comment] @relationship(type: "HAS_COMMENT", direction: OUT) author: User @relationship(type: "WROTE", direction: IN) createdAt: DateTime @timestamp(operations: [CREATE]) updatedAt: DateTime @timestamp(operations: [UPDATE]) } type Comment { id: ID! @id author: User @relationship(type: "COMMENTED", direction: IN) content: String! post: Post @relationship(type: "HAS_COMMENT", direction: IN) createdAt: DateTime @timestamp(operations: [CREATE]) updatedAt: DateTime @timestamp(operations: [UPDATE]) } ``` > Schema above simplified for clarity. ## Getting Started If you want to run this Blog locally follow the steps below. When it comes to [Configure environment variables](#how-to-configure-environment-variables-?) you will need a [running Neo4j instance](#how-to-start-neo4j-?) to point to. ### How to configure environment variables ? Each client and server folders contains a `./env.example` file. Copy this file, to the same directory, at `./.env` and adjust configuration to suit your local machine although the defaults may be fine. ### How to start Neo4j ? There are many ways to get started with neo4j such as; [Neo4j Sandbox](https://neo4j.com/sandbox/), [Neo4j Desktop](https://neo4j.com/developer/neo4j-desktop/) or [Docker](https://neo4j.com/developer/docker/). ### Steps Clone the repo; ``` $ git clone https://github.com/neo4j/graphql ``` Install ``` $ cd graphql && yarn install ``` => [Configure environment variables](#how-to-configure-environment-variables-) <= Run Seeder on; ``` $ yarn run neo-push:seed ``` > Checkout the seeder its using the OGM **Once seeded used the default credentials to log in** 1. Email: admin@admin.com 2. Password: password Run the webpack and graphql servers with; ``` $ yarn run neo-push ``` Navigate to http://localhost:4000 and sign up!  ## Authentication This application has two custom resolvers; sign in and sign up. In the resolvers we return a [JWT](https://jwt.io/). This JWT is stored in local storage on the client. The contents of the JWT is something like; ``` { "sub": "1234-4321-abcd-dcba", # user.id "iat": { ... } } ``` the `.sub` property is the users id. We use `NEO4J_GRAPHQL_JWT_SECRET` env var on the sever to configure the secret. > Note to keep things simple... This application has no JWT expiry or refreshing mechanism. Patterns you would implement outside of `@neo4j/graphql` so we deemed it less important in this showcase. When the client is making a request to server we attach the JWT in the `authorization` header of the request, the same header `@neo4j/graphql` looks at. ## Users At the core of the app but to keep things simple the UI doesn't have any profile page ect ect. ## Blogs Before you can create a post you must create a blog. Users can have many blogs with many post. Each blog can have an array of authors, whom can post to the blog. ### Dashboard Once logged in users are directed to the dashboard page;  ```graphql query myBlogs($id: ID, $offset: Int, $limit: Int, $hasNextBlogsoffset: Int) { myBlogs: blogs( where: { OR: [{ creator: { id: $id } }, { authors: { id: $id } }] } options: { limit: $limit, offset: $offset, sort: { createdAt: DESC } } ) { id name creator { id email } createdAt } hasNextBlogs: blogs( where: { OR: [{ creator: { id: $id } }, { authors: { id: $id } }] } options: { limit: 1 offset: $hasNextBlogsoffset sort: { createdAt: DESC } } ) { id createdAt } } ``` ### Pagination ⚠ Page info such as Relay spec is not supported in the current version of `@neo4j/graphql` so with the **My Blogs** and **Recently Updated Blogs** we query twice asking for the next item, to determine if there is a next page. Using this technique we can paginate the blog lists. > Image showing pagination with limit of 1, in the app its default to 10. >  ### Create Blog From the dashboard you can create a blog.  ```graphql mutation($name: String!, $sub: ID) { createBlogs( input: [ { name: $name creator: { connect: { where: { node: { id: $sub } } } } } ] ) { blogs { id name createdAt } } } ``` ### Edit Blog If your the creator of a blog you can edit its name.  ```graphql mutation editBlog($id: ID, $name: String) { updateBlogs(where: { id: $id }, update: { name: $name }) { blogs { id } } } ``` ### Assign Author If you are the creator of a blog you can assign other users as an author. You can also revoke too!  ```graphql mutation assignBlogAuthor($blog: ID, $authorEmail: String) { updateBlogs( where: { id: $blog } connect: { authors: { where: { node: { email: $authorEmail } } } } ) { blogs { authors { email } } } } ``` ```graphql mutation revokeBlogAuthor($blog: ID, $authorEmail: String) { updateBlogs( where: { id: $blog } disconnect: { authors: { where: { email: $authorEmail } } } ) { blogs { authors { email } } } } ``` ### Delete Blog If you are the creator of a blog you can delete it.  ```graphql mutation deleteBlog($id: ID) { deleteComments(where: { post: { blog: { id: $id } } }) { nodesDeleted } deletePosts(where: { blog: { id: $id } }) { nodesDeleted } deleteBlogs(where: { id: $id }) { nodesDeleted } } ``` ## Posts Users can have many posts with many comments. Blog creators and authors can edit the post. Blog creators and authors of the post can delete it. ### Create Post Once you have a blog. Either the creator or authors can create a post.  > Posts support markdown ```graphql mutation createPost($title: String!, $content: String!, $user: ID, $blog: ID) { cre