fbp-spec
========

A runtime-independent test framework for Flow Based Programming (FBP) component and graphs,
using declarative, data-driven testing.

One can use fbp-spec to do testing at multiple levels,
each approximately corresponding to the different architectural levels of Flow Based Programming:

* Unit (FBP component/subgraph)
* Integration (FBP graph)
* System (FBP runtime)

Status:

In production

* Used by several projects, including Ingress Table and BIG IoT NoFlo bridge
* Tested with several FBP runtimes: NoFlo, MicroFlo, Python example, MsgFlo
* Runners available for contious integration (CLI, Mocha) and interactively (in Flowhub)

Purpose & Scope

Note: fbp-spec is intended for use by application and component-library developers.

The following is considered out-of-scope:

* Testing conformance with the FBP protocol. Instead use fbp-protocol
* Testing an FBP runtime/engine itself. Instead use a testing framework for your particular runtime language/environment.

License

The MIT license

Usage

Installing

Set up fbp-spec as an NPM dependency

npm install --save-dev fbp-spec

or, install it globally. Useful if you just want the commandline tool.

npm install -g fbp-spec

Writing tests

Each declared test suite loads an FBP component (or graph) fixture,
and runs a set of test cases by sending a set of input data
to input ports and verifying the output data against the expected results.

``YAML
name: "Simple example of passing tests"
topic: "core/Repeat"
fixture:
type: 'fbp'
data: |
INPORT=it.IN:IN
OUTPORT=f.OUT:OUT
it(core/Repeat) OUT -> IN f(core/Repeat)

cases:
-
name: 'sending a boolean'
assertion: 'should repeat the same'
inputs:
in: true
expect:
out:
equals: true
-
name: 'sending a number'
assertion: 'should repeat the same'
inputs:
in: 1000
expect:
out:
equals: 1000
`

#### Multiple ports

You can send data to multiple inports and check expectations on multiple ports per testcase:

`YAML
-
name: '1 active track toggled high'
assertion: 'should give value1 color'
inputs:
tracks: 1
animation: [
0, # track idx
"0xEE00EE", # val0
"0xAA00AA", # val1
200, # period
50, # dutycycle
0, # offset
500 ] # duration
clock: 250
expect:
clock:
equals: 250
value:
equals: [0, 0x00AA] # FIXME: truncated
`

#### Sequence of packets

For testing components with state, you can sending multiple input packets
in sequence.

`YAML
-
name: 'sequence of data using spacy notation'
assertion: 'should pass'
inputs:
-
in: true
-
in: false
expect:
-
out:
equals: true
-
out:
equals: false
`

#### Extract data using path

With path you can specify a JSONPath
to extract the piece(s) of data the assertions will be ran against:

`YAML
-
name: 'select single value'
assertion: 'should pass'
inputs:
in: { outer: { inner: { foo: 'bar' } } }
expect:
out:
path: '$.outer.inner.foo'
equals: 'bar'
-
name: 'selecting many correct values'
assertion: 'should pass'
inputs:
in:
outer:
first: { foo: 'bar' }
second: { foo: 'bar' }
expect:
out:
path: '$.outer.*.foo'
equals: 'bar'
`

#### Skipping tests

Setting skip property on a testcase or suite, will cause it to not be ran.
Should contain a message of the reason for skipping.

`YAML
-
name: 'a test that is skipped'
assertion: 'will not be ran'
inputs:
in: 1000
expect:
out:
equals: 1000
skip: 'not implemented yet'
`

#### Using fixtures

One can use testing-specific components in the fixture, to simplify
driving the unit under test with complex inputs and performing complex assertions.

`YAML
fixture:
type: 'fbp'
data: |
INPORT=imagename.IN:NAME
INPORT=testee.PARAM:PARAM
INPORT=reference.IN:REFERENCE
OUTPORT=compare.OUT:SIMILARITY

generate(test/GenerateTestImage) OUT -> IN testee(my/Component)
testee OUT -> ACTUAL compare(test/CompareImage)
reference(test/ReadReferenceImage) OUT -> REFERENCE compare
cases:
-
name: 'testing complex data with custom components fixture'
assertion: 'should pass'
inputs:
name: someimage
param: 100
reference: someimage-100-result
expect:
similarity:
above: 0.99
`

#### Supported assertions

Instead of equals you can use any of the supported assertion predicates. Examples include:

type
above
below
contains
haveKeys
includeKeys

For a full set of assertions, see the schema

#### More

A comprehensive set of examples can be found under ./examples.
For the detailed definition of the dataformat for tests, see schemata/.

Running tests with fbp-spec commandline tool

The simplest and most universal way of running tests is with the fbp-spec commandline tool.

$ fbp-spec --address ws://localhost:3333 examples/multisuite-failandpass.yaml

MultiSuite, failing tests
sending a boolean with wrong expect
should fail: ✗ Error: expected true to deeply equal false
sending a number with wrong expect
should fail: ✗ Error: expected 1000 to deeply equal 1003
MultiSuite, passing tests
sending a boolean
should repeat the same: ✓
sending a number
should repeat the same: ✓

The --command options can be used to specify a command which will start the runtime under test:

fbp-spec --command "python2 protocol-examples/python/runtime.py"

It sets the exit status to non-zero on failure, so is suitable for integrating into a Makefile or similar.

Running tests by integrating with Mocha

Mocha iss a popular test runner framework for JavaScript/CoffeeScript on browser and node.js.

Since fbp-spec communicates with your runtime over a network protocol,
you can use this also when your project is not JavaScript-based.
The Mocha runner is for instance used in microflo-core
to test C++ components for microcontrollers & embedded devices.

You can have your fbp-spec tests run in Mocha by calling the fbpspec.mocha.run() function, in a file which is
executed with the standard Mocha runner. Eg. mocha --reporter spec tests/fbpspecs.js

// fbpspecs.js
fbpspec = require('fbp-spec');

rt = {
protocol: "websocket",
address: "ws://localhost:3569",
secret: "py3k", // Optional. If needed to connect/authenticate to runtime
command: 'python2 protocol-examples/python/runtime.py' // Optional. Can be used to start runtime automatically
};
fbpspec.mocha.run(rt, './examples/simple-passing.yaml', { starttimeout: 1000 });

The tests can be specified as a list of files, or directories.
You can use the standard grep option of Mocha to run only some tests.

For CoffeScript example, see ./spec/mocha.js.

Running tests interactively in Flowhub

Flowhub IDE (version 0.11 and later) has integrated support for fbp-spec. No installation is required.

* Open existing project, or create a new one
* Open a component, and write/copypaste in a test in the Tests panel
* Ensure you have a runtime set up, and connected

When you make changes to your project (components,graphs) or tests, Flowhub will now automatically (re-)run your tests.
You can see the status in the top-right corner. Clicking on it brings up more details.

Generating tests programatically

The test-format defined by fbp-spec is fairly generic and versatile. It is intended primarily as
a format one directly specifies tests in, but can also be generated from other sources.

Sometimes data-driven testing, one does a large amount of very similar tests,
with multiple test-cases per set of input data.
By capturing only the unique parts of testcases in a specialied data-structure (JSON, YAML, etc),
and then transforming this into standard fbp-spec files with some code, adding/removing
cases becomes even easier.
For instance in imgflo-server, testcases
can be defined by providing a name, an URL and a reference result (a file with naming convention based on name).

Similarly, one can generate testcases using fuzzing, schema-based, model-based or similar tools.

Integrating test runner in an application

The test runner code is accessible as a JavaScript library,
and can be integrated into other apps (like Flowhub does).
See examples of commandline and webappp usage.

Add supporting for a new runtime

You need to implement the FBP network protocol.
At least the protocol:runtime, protocol:graph, and protocol:network` capabilities are required.

All transports supported by fbp-protocol-client)
are supported by fbp-spec, including WebSocket, WebRTC, and iframe/postMessage.

fbp-spec is intended to be used with flow-based and dataflow-programming,
but might be useful also outside these programming paradigms. Try it out!

Writing a test runner in another language

As long as you stay compatible with the fbp-spec testformat
and FBP protocol,
you can implement a compatible runner in any programming language.

You can consider the fbp-spec code (in CoffeeScript) as a reference implementation.