CF-OPENAPI

#### Main goals:

1) openapi.json linting

2) micro-service startup initialization:
- expose openapi.json through /api/openapi.json endpoint
- expose ReDoc for openapi.json through /api endpoint
- expose openapi.json aggregated from dependency services through /api/admin/openapi.json endpoint
- expose ReDoc for aggregated openapi.json through /api/admin endpoint
- fetch dependency services' openapi.json specs on startup
- push openapi.push event with micro-service openapi.json on startup
- listen to openapi.push event for dependency services
- endpoints generation from openapi.json
- scope acl through generated endpoints
- abac acl through generated endpoints

Usage

$3

npm i @codefresh-io/cf-openapi

yarn add @codefresh-io/cf-openapi

$3

If you want to lint the openapi.json file:

``shell
npm i -g @codefresh-io/cf-openapi-validator

validate and lint using default path ./openapi.json (relative to pwd)

cf-openapi-validator lint

given a path

cf-openapi-validator lint ./some-openapi.json

lint post-processed openapi file (see: ./lib/components/Processor.component.js)

cf-openapi-validator lint -p
`

##### NOTE: node version of env to which installed validator cli should be the same as project required node version

$3

#### Note: this functionality is already integrated into @codefresh-io/service-base

#### Flow:

`js
const express = require('express');

const { openapi } = require('@codefresh-io/cf-openapi');
const eventbus = require('@codefresh-io/eventbus')
const config = require('./service.config');

const app = express();

const publishInterface = (serviceName, spec) => {
return eventbus.publishEvent('openapi.push', {
aggregateId: serviceName,
props: {
spec: JSON.stringify(spec)
}
}, true, true);
};

const subscribeInterface = (handler) => {
eventbus.subscribe('openapi.push', (data) => {
const serviceName = data.aggregateId;
const spec = JSON.parse(data.props.spec);
return Promise.resolve()
.then(() => handler(serviceName, spec));
});
};

openapi.init(config)
openapi.endpoints().addDependenciesSpecMiddleware(dependenciesMiddleware)
openapi.endpoints().register(app)
openapi.dependencies().fetch();
openapi.events().setPublishInterface(publishInterface)
openapi.events().setSubscribeInterface(subscribeInterface)

app.listen(8080);

openapi.events().subscribe();
openapi.events().publish();
`


#### Using multiple instances

Openapi is a "module-singleton" where all components are singletons.
This covers most cases except services which consist of multiple app instances (for example cf-api).

For this exception use next code:

`js
const { openapi: first } = require('@codefresh-io/cf-openapi').getInstance('first');
const { openapi: second } = require('@codefresh-io/cf-openapi').getInstance('second');

first.init(serviceConfig_1)
second.init(serviceConfig_2)
`


#### Config

Config:

`js
{
name: PIPELINE_MANAGER, // service name (required)
root: APP_ROOT, // root path from which openapi.json lookup will be performed
openapi: {
spec: {
specPath: '/api/openapi.json', // default
redocPath: '/api', // default
filename: './openapi.json' // default
},
dependenciesSpec: {
specPath: '/api/admin/openapi.json' // default
redocPath: '/api/admin' // default
}
}
}
`

Use false value to explicitly disable spec or dependenciesSpec:
`js
{
openapi: {
spec: false,
}
}
`

##### Note: since all openapi properties are default the whole openapi property can be omitted

Dependency services are described inside the openapi.json using x-internal-services field:

`json
{
"openapi": "3.0.0",
"info": {},
"x-internal-services": [
"pipeline-manager"
]
}
`

Service names are validated through @codefresh-io/internal-service-config.
See the readme for available service names.




$3

#### Handler

In the regular express application you do:
`js
// path: /app/controllers/some-endpoint.controller.js

class Controller {
handleSomething(req, res, next) {
console.log(req.params.myParam);
// do some logic here
res.send({ /.../ })
}
}

module.exports = new Controller();
`

`js
// path: /app/index.js

const express = require('express');
const someEndpoint = require('./controllers/some-endpoint.controller.js')

const app = express();


app.get('/api/some/endpoint/:myParam', someEndpoint.handleSomething);

app.listen(8080);
`

Using cf-openapi you will do the same routing using openapi.json file located on
the root level of the directory with your app. The root dir will be scanned recursively for
files with .controller.js, .middleware.js and *.condition.js endings
to load the

##### NOTE: you need to follow the next rules:
`
1) follow the naming convention: .controller.js, .middleware.js and *.condition.js
2) these files should return an instance of class or an object with functions
`

Here you can see the same routing configuration as in the example above:

`js
// path: /app/openapi.json

{
"openapi": "3.0.0",
"info": {
/.../
},

// this is used as base path for all registered endpints
"x-base-path": "/api",
"paths": {

// will be used as route: app.get('/some/endpoint', someEndpoint.handleSomething),
// "myParam" will be used to get the param by name: req.params.myParam
"/some/endpoint/{myParam}": {
"get": {
"tags": [],

// you always need to specify this (it's for api docs)
"operationId": "some-endpoint",

// this field is also required for skd usage like: sdk.someEndpint.requestHandleSomething()
"x-sdk-interface": "someEndpoint.requestHandleSomething",

"parameters": [
{
"in": "path",
"name": "myParam",
"schema": {
"type": "string"
},
"required": true
}
],

// this property is used to configure routing
"x-endpoint": {

// isEnpoint=false means that method handleSomething() will call res.send() function
// otherwise handleSomething() should return a value
"isEndpoint": false,

"preMiddleware": [],
"postMiddleware": [],

// this means: get some-endpoint.controller.js file and use method handleSomething
"handler": "some-endpoint.handleSomething"
},
"responses": {
/.../
}
}
}
}
}

`

`js
// path: /app/controllers/some-endpoint.controller.js

class Controller {
handleSomething(req, res, next) {
console.log(req.params.myParam);
// do some logic here
res.send({ /.../ })
}
}

// or return the value if isEndpoint is not specified or true
// -- return value will be sent automatically

class Controller {
handleSomething(req) {
console.log(req.params.myParam);
// do some logic here
return { /.../ }
}
}

module.exports = new Controller();
`

`js
// path: /app/index.js

const express = require('express');
const { openapi } = require('@codefresh-io/cf-openapi');
const app = express();

openapi.endpoints().init(app);

app.listen(8080);
`

#### Middleware

If you want to add middleware to your route like:

`js
app.get('/some/endpoint/:myParam',
(req, res, next) => {
console.log(req.params.myParam);
next();
},
someEndpoint.handleSomething,
)
`

You should add logic.middleware.js file:

`js
// path: /app/logic.middleware.js

module.exports = {
logMyParam(req, res, next) {
console.log(req.params.myParam);
next();
}
}
`

and following configuration:
`js
{
/.../
"x-endpoint": {
"preMiddleware": [
"logic.logMyParam"
],
"postMiddleware" [],
"handler": "some-endpoint.handleSomething"
},
/.../
}
`

##### NOTE: same should be applied if you want to use error middleware in postMiddleware array

#### Condition

If you want to add some condition on process env which will disable endpoint:

`js
const { DISABLE_MY_ENDPOINT } = process.env;

if (DISABLE_MY_ENDPOINT !== 'true') {
app.get(/..../)
}
`

Then you should create env.condition.js file:

`js
// path /app/env.condition.js

module.export = {
// should only return true or false
shouldEnableMyEndpoint() {
return process.env.DISABLE_MY_ENDPOINT !== 'true'
}
}
`

and following configuration:

`js
{
/.../
"x-endpoint": {
"preMiddleware": [],
"postMiddleware": [],
"condition": "env.shouldEnableMyEndpoint", // if true -- endpoint will be loaded
"handler": "some-endpoint.handleSomething"
},
/.../
}
`

$3

#### Overview

Cf-openapi lib provides an ability to use scope acl middleware to control
which scopes current request authentication should have to access current endpoint.

##### NOTE: by default this functionality is disabled -- to enable this you must provide a scopeExtractor function

`js
// some custom implementation -- should consume request object
// and return array of strings
function scopeExtractor(request) {
return request.user.scopes;
}

openapi.endpoints().setScopeExtractor()
`

##### NOTE: if you already defined your auth middleware in the preMiddleware -- you should move it to auth.middleware

`js
{
/.../
"x-endpoint": {
"auth": {
"middleware": [
"auth.isAuthenticated"
]
},
"preMiddleware": [],
"postMiddleware": [],
"handler": "some-resource.handleRequest"
}
/.../
}
`

#### Rules

A scope for endpoint consists from and one or more
defined for this resource delimited by : character:

`
Definition: '::'

Examples:
'builds:read'
'builds:read:status'
'pipelines:write'
`

User scope used to validate his access to an endpoint can be reduced to just resource definition
or parent scope:

`
User scope -> access to endpoint with scope:
'builds' -> 'builds:read'
'builds:read' -> 'builds:read:status'
'pipelines' -> 'pipelines:write'
`

##### ATTENTION: Once scope acl is enabled cf-openapi will automatically go through all paths in the openapi.json which have x-endpoint trying to automatically define endpoint scope following the next rules:

`
1) will be taken from url root
/pipelines/{name} -> resource-name = 'pipelines'
/builds -> resource-name = 'builds'

2) will be taken from request method
get, head, options -> 'read'
post, patch, put, delete -> 'write'
`

##### NOTE: There is another level of implicitness applied from abac acl action property:

`js
{
/.../
"x-endpoint": {
"auth": {
"acl": {
"action": "create"
}
}
}
/.../
}
`

Rules for action property:
`
read -> 'read'
create, update, delete -> 'write'
`

#### Scope condition

If you want scope acl to skip scope validation for some reasons - you should register scopeCondition:

`js
// validate scopes only if user authentication has scopes array
function scopeCondition(request, endpointScope) {
return !!request.user.scopes
}

openapi.endpoints().setScopeCondition(scopeCondition)
`

#### Review existing scopes

If you want to get all collected scopes from openapi.json
and registered by openapi.spec().registerAdditionalEndpoints({...})
-- then do the following:

`js
// scope object splitted by resource and containing descriptions
const scopeObject = openapi.spec().collectScopeObject();

// scope array with all existing scopes
const scopeArray = openapi.spec().collectScopeArray();
`

#### Missing scope handler

Once scope acl notices that user auth has not enough scope to access
this endpoint - an error is passed to express next() function. If you
want to specify the custom error - then you should use missingScopeHandler

`js
function missingScopeHandler(missingScopes) {
return new CustomError({
message: Missing scopes: ${missingScopes},
missingScopes,
})
}

openapi.endpoints().setMissingScopeHandler(missingScopeHandler)
`

#### Explicit scope configuration

If you want to explicitly configure scope for an endpoint then use the following properties:

`js
{
/.../
"x-endpoint": {
"auth": {
"acl": {
"resource": "pipelines" // custom
"scope": "run" // custom , can be "run:"
"disableScopes": false // use true if you want to disable scope acl for this endpoint
}
}
}
/.../
}
`

#### Programmatic scope acl middleware usage with Express.js

If there is still a need to use old router methods on bare express
together with scope acl provided by cf-openapi you can use openapi.endpoints().createGeneralScopeMiddleware()
and openapi.endpoints().createScopeMiddleware() helper methods.

`js
// you still need to define scope extractor
function scopeExtractor(request) {
return request.user.scopes;
}

// register scope extractor
openapi.endpoints().setScopeExtractor(scopeExtractor);

router.get('/pipelines',
auth.isAuthenticated,
openapi.endpoints().createGeneralScopeMiddleware(),
controller.handleRequest,
);
`

In the example above registered route was created with scope 'general'.
So user authentication should be request.user.scopes = ['general', ....].

If you want to declare some custom scopes to validate your endpoints programmatically
you should do the following:

`js
// you still need to define scope extractor
function scopeExtractor(request) {
return request.user.scopes;
}

// register scope extractor
openapi.endpoints().setScopeExtractor(scopeExtractor);

const ADDITIONAL_SCOPES = {
PIPELINES: 'pipelines',
PIPELINES_READ: 'pipelines:read',
PIPELINES_WRITE: 'pipelines:write',
PIPELINES_RUN: 'pipelines:run',
}

// register additional endpoint scopes
openapi.spec().registerAdditionalScopes({
[ADDITIONAL_SCOPES.PIPELINES]: {
[ADDITIONAL_SCOPES.PIPELINES]: 'Full access to pipelines',
[ADDITIONAL_SCOPES.PIPELINES_READ]: 'Read access to pipelines',
[ADDITIONAL_SCOPES.PIPELINES_WRITE]: 'Write access to pipelines',
[ADDITIONAL_SCOPES.PIPELINES_RUN]: 'Run access to pipelines',
}
})

route.post('/pipelines/run',
auth.isAuthenticated,
openapi.endpoints().createScopeMiddleware({ scope: ADDITIONAL_SCOPES.PIPELINES_RUN }),
controller.run,
)
``