RESTinstance 1.0.1

Robot Framework test library for (RESTful) JSON APIs

Robot Framework test library for (RESTful) JSON APIs

Advantages

1. RESTinstance relies on Robot Framework’s language-agnostic, clean and minimal syntax, for API tests. It is neither tied to any particular programming language nor development framework. Using RESTinstance requires little, if any, programming knowledge. It builts on long-term technologies with well established communities, such as HTTP, JSON (Schema), Swagger/OpenAPI and Robot Framework.

2. It validates JSON using JSON Schema, guiding you to write API tests to base on properties rather than on specific values (e.g. “email must be valid” vs “email is [e-mail]”). This approach reduces test maintenance when the values responded by the API are prone to change. Although values are not required, you can still test them whenever they make sense (e.g. GET response body from one endpoint, then POST some of its values to another endpoint and verify the results).

3. It generates JSON Schema for requests and responses automatically, and the schema gets more accurate by your tests. Output the schema to a file and reuse it as expectations to test the other methods, as most of them respond similarly with only minor differences. Or extend the schema further to a full Swagger spec (version 2.0, OpenAPI 3.0 also planned), which RESTinstance can test requests and responses against. All this leads to reusability, getting great test coverage with minimum number of keystrokes and very clean tests.

Installation

Pick the one that suits your environment best.

As a Python package

On 3.6, 3.7 and 2.7, you can install and upgrade from PyPi:

pip install --upgrade RESTinstance

This also installs Robot Framework if you do not have it already.

As a Docker image

RESTinstance Docker image contains Python 3.6 and the latest Robot Framework:

docker pull asyrjasalo/restinstance

Usage

There is a step-by-step tutorial in the making, best accompanied with keyword documentation.

Quick start

1. Create two new (empty) directories tests and results.

2. Create a new file tests/YOURNAME.robot with content:

*** Settings ***
Library         REST    https://jsonplaceholder.typicode.com
Documentation   Test data can be read from variables and files.
...             Both JSON and Python type systems are supported for inputs.
...             Every request creates a so-called instance. Can be `Output`.
...             Most keywords are effective only for the last instance.
...             Initial schemas are autogenerated for request and response.
...             You can make them more detailed by using assertion keywords.
...             The assertion keywords correspond to the JSON types.
...             They take in either path to the property or a JSONPath query.
...             Using (enum) values in tests optional. Only type is required.
...             All the JSON Schema validation keywords are also supported.
...             Thus, there is no need to write any own validation logic.
...             Not a long path from schemas to full Swagger/OpenAPI specs.
...             The persistence of the created instances is the test suite.
...             Use keyword `Rest instances` to output the created instances.


*** Variables ***
${json}         { "id": 11, "name": "Gil Alexander" }
&{dict}         name=Julie Langford


*** Test Cases ***
GET an existing user, notice how the schema gets more accurate
    GET         /users/1                  # this creates a new instance
    Output schema   response body
    Object      response body             # values are fully optional
    Integer     response body id          1
    String      response body name        Leanne Graham
    [Teardown]  Output schema             # note the updated response schema

GET existing users, use JSONPath for very short but powerful queries
    GET         /users?_limit=5           # further assertions are to this
    Array       response body
    Integer     $[0].id                   1           # first id is 1
    String      $[0]..lat                 -37.3159    # any matching child
    Integer     $..id                     maximum=5   # multiple matches
    [Teardown]  Output  $[*].email        # outputs all emails as an array

POST with valid params to create a new user, can be output to a file
    POST        /users                    ${json}
    Integer     response status           201
    [Teardown]  Output  response body     ${OUTPUTDIR}/new_user.demo.json

PUT with valid params to update the existing user, values matter here
    PUT         /users/2                  { "isCoding": true }
    Boolean     response body isCoding    true
    PUT         /users/2                  { "sleep": null }
    Null        response body sleep
    PUT         /users/2                  { "pockets": "", "money": 0.02 }
    String      response body pockets     ${EMPTY}
    Number      response body money       0.02
    Missing     response body moving      # fails if property moving exists

PATCH with valid params, reusing response properties as a new payload
    &{res}=     GET   /users/3
    String      $.name                    Clementine Bauch
    PATCH       /users/4                  { "name": "${res.body['name']}" }
    String      $.name                    Clementine Bauch
    PATCH       /users/5                  ${dict}
    String      $.name                    ${dict.name}

DELETE the existing successfully, save the history of all requests
    DELETE      /users/6                  # status can be any of the below
    Integer     response status           200    202     204
    Rest instances  ${OUTPUTDIR}/all.demo.json  # all the instances so far

3. Chose Python installation? Let’s go (not that language):

robot --outputdir results tests/

If you chose the Docker method instead (recall the story about red and blue pill here, if you want), this is quaranteed to work in most environments:

docker run --rm -ti --env HOST_UID=$(id -u) --env HOST_GID=$(id -g) \
  --env HTTP_PROXY --env HTTPS_PROXY --network host \
  --volume "$PWD/tests":/home/robot/tests \
  --volume "$PWD/results":/home/robot/results \
  asyrjasalo/restinstance tests/

Tip: If you prefer installing from source, pip install --editable . and verify the installation with robot README.rst

Contributing

Bug reports and feature requests are tracked in GitHub.

We do respect pull request(er)s. Please mention if you do not want to be listed below as contributors.

A CircleCI job is created automatically for your GitHub pull requests as well.

Local development

On Linux distros and on OS X, may make rules ease repetitive workflows:

$ make help
all                  Run test, build, install and atest (default)
atest                Run acceptance tests
atest_py2            Run acceptance tests on Python 2
black                Reformat source code in-place
build                Build source dist and wheel
check-manifest       Run check-manifest for MANIFEST.in completeness
clean                Remove .venvs, builds, dists, and caches
dc                   Start docker-composed test API on background
dc_rm                Stop and remove docker-composed test API
flake8               Run flake8 for static code analysis
install              Install package from source tree, as --editable
install_pypi         Install the latest PyPI release
install_test         Install the latest test.pypi.org release
libdoc               Regenerate library keyword documentation
mypy                 Run mypy for static type checking
publish_pypi         Publish dists to PyPI
publish_test         Publish dists to test.pypi.org
pur                  Update requirements-dev for locked versions
pyroma               Run pyroma for Python packaging best practices
retest               Run failed tests only, if none, run all
test                 Run tests, installs requirements(-dev) first
uninstall            Uninstall the package, regardless of its origin

Running make runs rules test, build, install and atest at once, and uses separate virtualenvs .venvs/dev/ and .venvs/release/ to ensure that no (user or system level) dependencies interfere with the process.

If make is not available, you can setup for development with:

virtualenv --no-site-packages .venvs/dev
source .venvs/dev/bin/activate
pip install --editable .

To recreate the keyword documentation from source (equals to make libdoc):

python -m robot.libdoc REST docs/index.html

Acceptance tests

The testapi/ is built on mountebank. You can monitor requests and responses at localhost:2525

To start it with docker-compose (daemonized) and run all acceptance tests:

make atest

This uses rfdocker underneath to build a yet another container for tests. Host directories tests/ and results/ are accessed inside the container via the respective Docker volumes. Same arguments are accepted as for robot.

To run only specific test suite(s):

RUN_ARGS="--network=host --env HTTP_PROXY --env HTTPS_PROXY" ./rfdocker tests/output.robot

Host network is used to minimize divergence between different host OSes. It may or may not be necessary to pass any of RUN_ARGS in your environment, but there should be no downside either (on OS X --network=host is required).

If Docker (Compose) is not available, you can use npm’s npx to install mountebank npm package and start the very same test API (keep --localOnly for security):

npx mountebank --localOnly  --allowInjection --configfile testapi/apis.ejs

And run tests on Python:

python -m robot --outputdir results tests/

Docker releases

The Docker image is built with (included) rfdocker (regarding the changed parts) each time make atest is run.

To push it to your Docker registry as “latest” (remember to docker login):

./release_docker https://your.docker.registry.com/restinstance

For Docker Hub, just org/username will do:

./release_docker {{organization}}/restinstance

Credits

RESTinstance is under Apache License 2.0 and was originally written by Anssi Syrjäsalo.

It was first presented at the first RoboCon, 2018.

Contributors:

• jjwong for helping with keyword documentation and examples (also check RESTinstance_starter_project)

• Przemysław “sqilz” Hendel for using and testing RESTinstance in early phase (also check RESTinstance-wrapper)

• Vinh “vinhntb” Nguyen, #52.

• Stavros “stdedos” Ntentos, #75.

We use following Python excellence under the hood:

• Flex, by Piper Merriam, for Swagger 2.0 validation

• GenSON, by Jon “wolverdude” Wolverton, for JSON Schema generator

• jsonpath-ng, by Tomas Aparicio and Kenneth Knowles, for handling JSONPath queries

• jsonschema, by Julian Berman, for JSON Schema validator

• pygments, by Georg Brandl et al., for JSON syntax coloring, in terminal Output

• requests, by Kenneth Reitz et al., for making HTTP requests

See requirements.txt for all the direct run time dependencies.

REST your mind, OSS got your back.