Defining a blog service

Let's begin by defining our blog service in a Thrift file.

What you need

No preparation is required for this step. Do check that you've prepared the prerequisites.

1. Create a Thrift file

Create a Thrift file, blog.thrift in the {project_root}/src/main/thrift folder as follows. You can see the full version of the file here.

blog.thrift

namespace java example.armeria.blog.thrift

tip

See Sample service structure for the overall folder structure.

2. Define a service

Let's define our blog service in the blog.thrift file. We'll add structs, an exception, and service methods.

1. Add the BlogPost struct.

blog.thrift

struct BlogPost {
  1: i32 id;
  2: string title;
  3: string content;
  4: i64 createdAt;
  5: i64 modifiedAt;
}

2. Add structs for request and response objects as follows.

blog.thrift

struct CreateBlogPostRequest {
  1: string title;
  2: string content;
}

struct GetBlogPostRequest {
  1: i32 id;
}

struct ListBlogPostsRequest {
  1: bool descending;
}

struct ListBlogPostsResponse {
  1: list<BlogPost> blogs;
}

struct UpdateBlogPostRequest {
  1: i32 id;
  2: string title;
  3: string content;
}

struct DeleteBlogPostRequest {
  1: i32 id;
}

3. Add the BlogNotFoundException.

blog.thrift

exception BlogNotFoundException {
  1: string reason
}

4. Add a service with methods for create, read, update, and delete operations.

blog.thrift

service BlogService {
  BlogPost createBlogPost(1:CreateBlogPostRequest request),

  BlogPost getBlogPost(1:GetBlogPostRequest request) throws (1:BlogNotFoundException e),

  ListBlogPostsResponse listBlogPosts(1:ListBlogPostsRequest request),

  BlogPost updateBlogPost(1:UpdateBlogPostRequest request) throws (1:BlogNotFoundException e),

  void deleteBlogPost(1:DeleteBlogPostRequest request) throws (1:BlogNotFoundException e),
}

3. Compile the Thrift file

Compile the blog.thrift file to generate Java code. You can refer to the full build.gradle file for generating code with Gradle Thrift Plugin.

./gradlew compileThrift

You'll see the generated Java code in the {project_root}/build/generated-sources/thrift/gen-java/example/armeria/blog/thrift/ folder.

Next step

In this step, we've defined a Thrift file for our service and generated Java code. Next, we'll run a service and test the connection.