Yapi is the hacker's Postman, Insomnia or Bruno.

Yapi is an OSS command line tool that makes it easy to test APIs from your terminal. Yapi speaks HTTP, gRPC, TCP, GraphQL (and more coming soon).

yapi in action

Heads up! Yapi is early, early alpha software

I use yapi daily in my development workflow. However, yapi is a SUPER young project and will have bugs, missing features and rough edges.

If you download yapi, I would LOVE your feedback on how to make it better. Please open an issue if you have any suggestions or find any bugs!

Elephant in the room, why another API client?

I have a separate blog post going into detail on this, but the short version

I built yapi for me to quickly test APIs without curl incantations, and without%20having%20to%20manually%20encode%20query%20parameters%21.

(I'm also not into having yet another 200 exabyte Electron app on my laptop either...)

I initially did this with a simple bash script that used curl & jq.

Then I was working on other projects using gRPC and TCP, and I saw that I could support them with a little grpcurl and netcat magic.

Eventually I realised that I was building a new tool, and that other people might find it useful too, so I rewrote it in Go, added more features and released it as yapi.

Show me some examples!

POST

This request:

# create-issue.yapi.yml
yapi: v1 # specify yapi version
method: POST # or GET, PUT, DELETE, PATCH, etc.
url: https://api.github.com/repos/jamierpond/yapi/issues
headers:
  Accept: application/vnd.github+json
  Authorization: Bearer ${GITHUB_PAT} # supports environment variables
body: # defaults to JSON body, converted automatically
  title: Help! yapi made me too productive.
  body: Now I can't stop YAPPIN' about yapi!
expect: # supports expected response tests
  status: 201
  assert: # assert using jq syntax
    - .body == "Now I can't stop YAPPIN' about yapi!"

Gives you this response:

yapi run create-issue.yapi.yml
{
  "active_lock_reason": null,
  "assignee": null,
  "assignees": [],
  "author_association": "OWNER",
  "body": "Now I can't stop YAPPIN' about yapi!\n",
  // ...blah blah blah
}

URL: https://api.github.com/repos/jamierpond/yapi/issues
Time: 579.408625ms
Size: 2.3 kB (1 lines, 2288 chars)

[PASS] status check
[PASS] .body == "Now I can't stop YAPPIN' about yapi!"

(Only the JSON goes to stdout, the rest goes to stderr, so is pipeable!)

Yapi supports chaining requests between protocols

Multi-protocol chaining

Yapi makes it easy to chain requests and share data between them, even if they are different protocols.

# multi-protocol-chain.yapi.yml
yapi: v1
chain:
  - name: get_todo # HTTP request
    url: https://jsonplaceholder.typicode.com/todos/1
    method: GET
  - name: grpc_hello # gRPC request
    url: grpc://grpcb.in:9000
    service: hello.HelloService
    rpc: SayHello # Supports reflection if server has it enabled
    plaintext: true
    body:
      greeting: $get_todo.title # use data from previous request
    expect:
      assert:
        - .reply == "hello delectus aut autem" # assert on gRPC response

Run this example in the yapi playground

Integration Testing with yapi

Yapi has built-in support for writing integration tests with expectations and assertions.

yapi: v1
method: GET
url: https://api.github.com/repos/jamierpond/yapi/issues/5
headers:
    Accept: application/vnd.github+json
expect:
    status: 200
    assert:
      - .state == "closed"
      - .closed_by.login == "jamierpond"

Run this example in the yapi playground

Yapi has an LSP Server for IDE Integration

Yapi comes with a Language Server Protocol (LSP) server that provides syntax highlighting, autocompletion and validation for yapi request files in editors that support LSP (Neovim, etc), you can also use the yapi Neovim plugin (still early days).

At some point I'll write the VSCode extension too, please make an issue if you think this is important!

Getting Started with Yapi

To get started with yapi, simply install it using the instructions on the yapi GitHub repository and start creating your first request files!

Contributing to Yapi

Yapi is an open-source project maintained by just me, Jamie. If you find bugs or have feature requests, please open an issue on the yapi GitHub repository. Pull requests are very welcome too!