Openman

A postman to openapi spec conversion tool, which automatically

• Converts your postman collection (2.1) to OpeanAPI Spec (3.0.0)
• Mocks your openapi collection to generate responses from postman examples

Other than these, this tool can easily handle ignored fields in responses (explained below)

NOTE Please use postman collection ver 2.1 export (and not 2.0 or earlier). This library only support postman collection 2.1

Installation

NOTE This repo needs you to have python 3.5+ installed

PIP

pip install openman

Manual

To install, simple clone this repo

git clone https://github.com/codeasashu/openman.git

and install

python setup.py install

Quick Start

This tool can be used as a python package or as a standalone cli.

To start, simply type openman --help and it will display help

Usage: openman [OPTIONS] COMMAND [ARGS]...

  Convert or mock your postman collection to openapi schema

Options:
  --help  Show this message and exit.

Commands:
  convert
  mock

Convert postman to openapi spec

Easy!! Just use convert command (default output is yaml)

openman convert postman-collection.json spec.yaml

Or, you can output to json by

openman convert -f json postman-collection.json spec.yaml

Mocking spec

I am using the some cherry on top of the awesome project Connexion

Basically, I am using postman example as mock responses, given the request has matching parameters (query, headers etc.). Even if they do not match, this tool gives out the mock responses for provided schema.

openman mock spec.yaml

Ignore schema

Sometimes, your api responses have some data which varies. For instance, consider this response for the api POST /user:

{
    "result": {
        "timestamp": 1572696732,
        "username": "abc",
        "tags": {
            "tag1" : "something",
            "tag3": "somethig else"
        },
        "some-changing-key": "whatever"
    }
}

You do want to record the username, timestamp fields, but what about some-changing-key field? What about fields inside tags? You want to keep the tags key as it will always be included in response, but do not want to keep some-changing-key as it may or maynot appear in responses.

Sometimes you may want to ignore only the values of a key, while sometimes you want the key value pair to be ignored alltogether

For such cases, you may not want to document them. For such purpose, Ignore file is used.

In ignore file, you can document the fields you want the openman to ignore. It uses the jsonpath-rw library and uses its syntax (which is quite easy to learn).

To ignore only values but keep the keys, simple use the jsonpath-rw syntax that points to the key. For ex- $.result.tags.[*] will find everything inside tags field in result object.

To ignore both key and values, simply use the above method, i.e. write your jsonpath-rw regex that matches the path, and append :a to it. For example, if you want to delete everything inside tag including tag field itself, you can do so by: $.result.tags.[*]:a

Taking above example, you want to ignore following fields:

• everything inside tags (ignore value but NOT the key tags)
• some-changing-key field (ignore both key and value)

You can define them in a file ignore.yaml as such:

schema:
   /user:
     post:
       200:
         - '$.result.tags.[*]' //Ignore everything inside tags field
         - '$.result.some-changing-key:a' //Ignore 'some-changing-key'. Note the leading :a 

and then you can convert your postman collection to openapi spec without these fields:

openman -i ignore.yaml postman-collection.json spec.yaml

PS: Leading :a in jsonpath-rw syntax with ignore both the key and values, otherwise only values are ignored.

Change spec format

The default output conversion format is yaml. However, you can easily change the format to json by:

openman -f json postman-collection.json spec.json