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Open API Integration

OpenAPI is the name of the initiative behind defining Swagger specification which describe a REST web-API.

Murano is utilizing this format as description to integrate its internal and external Services. It also provided the dynamic documentation support for UI Editor auto-completion & docs.exosite.com/reference/services.

Find information about publishing exchange element on docs.exosite.com/reference/ui/exchange/authoring-elements-guide

Murano Service Definition

Murano Services are Web-Services providing capability through REST HTTP APIs. To expose and describe those APIs Murano uses the Swagger V2 (OpenAPI) standard with a few additional properties described in this page. Malformed schema will be rejected upon creation to avoid later confusion for the user.

Examples

Several example are available and can be used as a base for new services:

Example 1: Minimal Service

This is a simple service definition with x-exosite-health-path and x-exosite-example fields to describe the minimal service.

Link: minimalservice.yaml

Example 2: Storage Service

This is a minimal service definition for a Storage service with custom configuration settings. It demonstrates how to use of the solution lifecycle event: x-exosite-init, x-exosite-info, x-exosite-update & x-exosite-gc.

Link: storageservice.yaml

Example 3: Federated Service

This is a SMS notifications service definition for using some service provider. It is include the x-exosite-config-parameters, x-exosite-userfield, x-exosite-secret-field, x-exosite-restricted and x-exosite-example fields.

Link: sms.yaml

Quick Start

Validation

At each following steps you can run the validation script to test your syntax.

Required dependency

First install nodeJs: https://nodejs.org/en/download/ And install dependencies:

npm i

Validate your schema

npm test

Will validate all schemas in the 'examples' folder. You can provide a source folder as input parameter.

npm test /path/to/folder

TIPS:

Step 1: Start Editing your API swagger v2

The first step is to create a file in yaml format to describing your web service API.

If your web service API implementation is not done yet, have a look to the various tools & frameworks available to help building APIs following swagger specification. Including the official stub code generator.

Otherwise start building your yaml file in your favorite code editor. You may consider using the swagger online editor to help you get started.

Step 2: Murano Required Fields

Once you have a valid swagger description, take the time to go through this document to make sure all required fields and section as described in Schema Definition, including in the nested structures. (e.g. swagger, info, host, paths, etc).

Step 3: Murano Custom Fields

Murano provides several swagger extension tag, it is time to review them and see if your service usage scenario requires them. (e.g. x-exosite-example, x-exosite-init, x-exosite-health-path and so on.)

Step 4: Describe Your Service

The Swagger file is the documentation available to your user. Make sure it is fully document. In particular the description field is always required in any nested structure. See the Service Documentation chapter.

Service Documentation

In Murano, services capabilities are documented through the OpenAPI schema and will be used for dynamic documentation. It is therefore important to provide clear description for each element in the schema.

How to document the Service:

  • info section: This top level information will be the flag of your service in Murano. Make sure the title and description are comprehensive and fully describe your service capability. You are also encouraged to add links to your own documentation and tutorials if you have one
  • description field: A detailed description of the [operation, parameter, etc..], supporting MD tags. This field is always required.
  • summary field: A short one-line plain text description for operations & parameters.

Make some examples:

  • example field: Data structure examples for JSONSchema definition.
  • x-exosite-example field: Scripting example for Operation calls.

Schema Definition

Required Fields

Important: The description field is always required including in nested JSONSchema definitions.

Field Name Type Example Description
swagger string '2.0' Specifies the Swagger Specification version being used. It can be used by the Swagger UI and other clients to interpret the API listing. The value MUST be 2.0.
info object Info Object Service description.
host string 'domain.of.your.service' Used by Murano to make service calls. The external host (name or ip) serving the Service.
paths string Paths Object Defines the Service API capability, called operation.

Murano Specific Fields (Optional)

Field Name Type Example Description
x-exosite-health-path string '/health' Path to health check endpoint. Default basePath. A GET request will be made expecting a 2xx status code.
x-exosite-init string 'someInit' An operationId reference triggered by Murano when a user subscribe to this service.This is concretely done when a service get configured in a given solution including during a solution creation.

This event is usually used for service to setup namespace for the user solution. Example: create a new database.
x-exosite-info string 'someInfo' An operationId reference triggered by Murano to retrieve a subscription informations to return to the users.
x-exosite-update string 'someUpdate' An operationId reference triggered by Murano when a user update the service configuration for this solution.
x-exosite-gc string 'someGc' An operationId reference triggered by Murano when a user un-subscribe to this service. Including when the related solution is deleted.
x-exosite-token string 'mysecrettoken' Token used when this service is trying to make a call to dispatcher public API. Include a header: authorization: <service-alias> <token-value> when making a request to public dispatcher API.
x-exosite-config-parameters [object] [Config Parameters Object] An array of parameters (JSON schema) defining the data set in the service Configuration parameters field for this serviceconfig.(Service configuration parameters are used as default value during operation call from Lua script)

Optional Fields

Field Name Type Example Description
basePath string '/' Concatenated to host by Murano for service calls
schemes [https] ['https'] Used by Murano for service calls along with host & basePath. Must be https.
consumes [string] ['application/json'] A list of MIME types the APIs can consume. Currently only 'application/json' (default) and 'application/x-www-form-urlencoded' is supported.
produces [string] ['application/json'] A list of MIME types the APIs can produce. Currently only 'application/json' (default) is supported.
definitions object Definitions Object An object to hold data types produced and consumed by operations.
parameters object Parameters Definitions Object An object to hold parameters that can be used across operations. This property does not define global parameters for all operations.
responses object Responses Definitions Object Expected results of the service calls.
securityDefinitions object Security Definitions Object Security scheme definitions that can be used across the specification.
security [object] [Security Requirement Object] Security auth to enforce for all service operations, need to be matched with the item name defined in securityDefinitions section.
tags [object] [Tag Object] A list of tags used by the specification with additional metadata. The order of the tags can be used to reflect on their order by the parsing tools. Not all tags that are used by the Operation Object must be declared. The tags that are not declared may be organized randomly or based on the tools' logic. Each tag name in the list MUST be unique.
externalDocs object External Documentation Object Additional external documentation.

Info Object

The object provides metadata about the API. Reference: the official Info Object documentation.

Info Object Example:

title: Swagger Sample App
description: This is a sample server Petstore server.
termsOfService: http://swagger.io/terms/
contact:
  name: API Support
  url: http://www.swagger.io/support
  email: [email protected]
license:
  name: Apache 2.0
  url: http://www.apache.org/licenses/LICENSE-2.0.html
version: "1.0.1"
Required Fields
Field Name Type Example Description
title string Swagger Sample App The title of the application.
description string This is a sample server Petstore server. A full description of the service. Can contain HTML tags.
contact object Contact Object The contact information for the exposed API.
version string 1.0.0 Provides the version of the application API.
Optional Fields
Field Name Type Example Description
termOfService string http://swagger.io/terms/ The Terms of Service for the API.
license object License Object The license information for the exposed API.

Paths Object

Holds the relative paths to the individual endpoints. The path is appended to the basePath in order to construct the full URL. Reference: the official Paths Object documentation.

Paths Object Example:

/pets:
  get:
    description: Returns all pets from the system that the user has access to
    produces:
    - application/json
    responses:
      '200':
        description: A list of pets.
        schema:
          type: array
          items:
            $ref: '#/definitions/pet'
Required Fields
Field Pattern Type Example Description
/{path} object Path Item Object A relative path to an individual endpoint. The field name MUST begin with a slash. The path is appended to the basePath in order to construct the full URL. Path templating is allowed.

Path Item Object

Paths and underlying operations defines the features exposed to Murano and allow user Lua scripts to make service calls. Reference: official Path Item Object documentation.

Path Item Object Example:

get:
  description: Returns pets based on ID
  summary: Find pets by ID
  operationId: getPetsById
  produces:
  - application/json
  - text/html
  responses:
    '200':
      description: pet response
      schema:
        type: array
        items:
          $ref: '#/definitions/Pet'
    default:
      description: error payload
      schema:
        $ref: '#/definitions/ErrorModel'
parameters:
- name: id
  in: path
  description: ID of pet to use
  required: true
  type: array
  items:
    type: string
  collectionFormat: csv
Optional Fields
Field Pattern Type Example Description
$ref string '#/definitions/Pet' Allows for an external definition of this path item. The referenced structure MUST be in the format of a Path Item Object. If there are conflicts between the referenced definition and this Path Item's definition, the Path Item’s definition prevails.
get object Operation Object A definition of a GET operation on this path.
put object Operation Object A definition of a PUT operation on this path.
post object Operation Object A definition of a POST operation on this path.
delete object Operation Object A definition of a DELETE operation on this path.
options object Operation Object A definition of a OPTIONS operation on this path.
head object Operation Object A definition of a HEAD operation on this path.
patch object Operation Object A definition of a PATCH operation on this path.
parameters [object] [Parameter Object / Reference Object] Common set of parameters for all operations in this path.
Important: At least one of path parameters or operation parameters is required.

Operation Object

Describes a single API operation on a path. Reference: official Operation Object documentation.

Operation Object Example:

tags:
- pet
summary: Updates a pet in the store with form data
description: ""
operationId: updatePetWithForm
consumes:
- application/json
produces:
- application/json
parameters:
- name: petId
  in: path
  description: ID of pet that needs to be updated
  required: true
  type: string
- name: name
  in: query
  description: Name of the object to fetch
  required: false
  type: string
- name: status
  in: body
  description: Updated status of the pet
  required: true
  schema:
    type: array
    items:
      type: string
responses:
  '200':
    description: Pet updated.
  '405':
    description: Invalid input
security:
- petstore_auth:
  - write:pets
  - read:pets
x-exosite-hidden: false
x-exosite-restricted: false
Required Fields
Field name Type Example Description
operationId string 'myfunction' Service operation reference, must be unique within the service. Used by in Lua script along with service Alias to make service calls.Eg. Servicealias.myfunction(parameters)
description string Something description A verbose explanation of the operation behavior. Used in the documentation.
parameters [object] [Parameter Object / Reference Object] Operation specific parameters.
responses object Responses Object Expected results of the service calls.
At least one response type is required.
Murano Specific Fields(Optional)
Field name Type Example Description
x-exosite-hidden boolean false If set to true: hide this operation from documentation.
x-exosite-restricted boolean false If set to true: prevent this operation from being exposed in Lua scripting

For example, this option is used to restrict life-cycle operations like initialize or delete the user namespace.
x-exosite-example string: Lua -- Example of Lua
script using the Operation

local parameters = {myparameter = "value"}
Local result = Myservice.myoperation(parameters)		 Provide an example of the usage of the operation call.
The value is required to be a valid Lua script string.

Important: A known bug requires to put a double return carriage after each Lua comment.
x-exosite-timeout integer[1000..30000] 10000 Operation timeout in ms.
Default value: 10sec.

Parameter Object

Describes a single operation parameter. Reference: official Parameter Object documentation.

Parameter Object Example (Body Parameters):

name: user
in: body
description: users to add to the system
required: true
schema:
  description: List of users
  type: array
  items:
    description: user id
    type: string

In this case the top level body element is an array. Following case show embedded field.

name: user
in: body
description: body content
required: true
schema:
  description: Request data
  type: object
  properties:
    users:
      description: List of users
      type: array
      items:
        description: user id
        type: string

Parameter Object Example (Header Parameters):

name: user
in: header
description: user id
type: string

Parameter Object Example (Path Parameters):

name: user
in: path
description: user id
type: string # default
# required: true -> Path parameters are always required

Or a list with:

name: user
in: path
description: User list
type: array
items:
  description: user id
  type: string
collectionFormat: csv # default

Parameter Object Example (Optional Query Parameters):

name: id
in: query
description: list of ids
required: false # default
type: array
items:
  description: user id
  type: string
collectionFormat: multi
Required Fields
Field name Type Example Description
name string id The name of the parameter as provided from Lua scripting. Used by Murano for building service calls requests.
Important: Must be unique per operation. Keep in mind potential Path, Security and Operation parameters collision.
in string path The location of the parameter. Possible values are "query", "header", "path" or "body". Used by Murano to build the service calls http requests.
Important: "formData" is currently not supported by Murano.
description string Something description A description of the parameter.
Murano Specific Fields(Optional)
Field name Type Example Description
x-exosite-hidden boolean false If set to true: hide this parameter from documentation.
x-exosite-restricted boolean false If set to true: prevent this parameter to be available from Lua scripting. The value will get set from the service configuration parameters.

For example, this option is used to restrict credential parameters to be given from the script code and inforce the service configuration parameter.
x-exosite-from domain / solution_id / business_id domain / solution_id / business_id Populate this parameter from a user context value.
This option is generally used along with "x-exosite-restricted: true" to prevent user for overriding his context and potentially accessing other user data.
x-exosite-expand-body-parameters boolean true Default=true, for a body parameter of type=object, a value set to false would force the body parameter to be explicitly given from script call.
Example:
x-exosite-expand-body-parameters: true (default)
Keystore.set({key = "xxx", body = "value"})
x-exosite-expand-body-parameters: false
Keystore.set({key = "xxx", value = {value = "value"}})

Responses Object

A container for the expected responses of an operation. The container maps a HTTP response code to the expected response. It is not expected from the documentation to necessarily cover all possible HTTP response codes, since they may not be known in advance. However, it is expected from the documentation to cover a successful operation response and any known errors.

The default can be used as the default response object for all HTTP codes that are not covered individually by the specification.

The Responses Object must contain at least one response code, which must be the response for a successful operation call.

Reference: official Responses Object documentation

Responses Object Example:

'200':
  description: a pet to be returned
  schema:
    $ref: '#/definitions/Pet'
default:
  description: Unexpected error
  schema:
    $ref: '#/definitions/ErrorModel'
Required Fields
Field name Type Example Description
default object Response Object / Reference Object The documentation of responses other than the ones declared for specific HTTP response codes. It can be used to cover undeclared
{HTTP Status Code} object Response Object / Reference Object Any HTTP status code can be used as the property name (one property per HTTP status code). Describes the expected response for that HTTP status code.

Response Object

Describes a single response from an API Operation. Reference: official Response Object documentation.

Response Object Example:

description: A simple string response
schema:
  type: string
Required Fields
Field name Type Example Description
description string A simple string response A description of the response. Used in the documentation.
Optional Fields
Field name Type Example Description
schema object Schema Object JSON-Schema defining the response data. If this field does not exist, it means no content is returned as part of the response.

Security Definitions Object

A declaration of the security schemes available to be used in the specification. This does not enforce the security schemes on the operations and only serves to provide the relevant details for each scheme.

Reference: official Security Definitions Object documentation.

Security Definitions Object Example:

api_key:
  type: apiKey
  name: api_key
  in: header
Patterned Fields
Field Pattern Type Example Description
{name} object Security Scheme Object A single security scheme definition, mapping a "name" to the scheme it defines.

Security Scheme Object

Allows the definition of a security scheme that can be used by the operations. Supported schemes are basic authentication and an API key (either as a header or as a query parameter). (OAuth2 currently not supported.)

Important: Murano do not support "flow", "authorizationUrl", "tokenUrl" and "scopes" fields.

Reference: official Security Scheme Object documentation.

Fixed Fields
Field Pattern Type Example Validity Description
type string basic / apiKey / bearer Any Required. The type of the security scheme. Valid values are:
"Basic" for https://tools.ietf.org/html/rfc7617.
"bearer" for https://tools.ietf.org/html/rfc6750.
"apiKey" for a direct token transmission.
description string Description something Any A short description for security scheme.
name string api_key apiKey / bearer Required. The name of the header or query parameter to be used.
For "bearer" type the name of the parameter containing the value.
in string header apiKey Required. The location of the API key. Valid values are "query" or "header".
Murano Specific Fields
Field Pattern Type Example Validity Description
x-exosite-user-field string someAccount basic Required. Defines the parameter name providing the user credential value.
x-exosite-secret-field string someSecret basic Required. Defines the parameter name providing the secret credential value.
x-exosite-prefix string token apiKey A string to prefix in the header content.
E.g. X-secret: token <user token>
x-exosite-from string token apiKey Required. The parameter name containing the token value to add in the Authentication header or query parameter.
Basic

Standard Basic Authentication.

Example:

type: basic
x-userField: <account>
x-secretField: <secret>
APIKey

Flexible API Key (Token) authentication:

Example:

type: apiKey
name: secretHeader
in: header
x-exosite-prefix: Token
x-exosite-from: secret

Will generate header:

secretHeader: Token <value of secret parameter>
Bearer

For simplicity Murano added a custom authentication scheme following the Bearer standard, similar as Swagger V3.0 however missing in the version 2.0.

Example:

type: bearer
name: <source parameter name>

Will generate header:

authorization: Bearer <value of secret parameter>
Signature

Custom signature security signing the request in a header.

Example:

type: signature
# name: <name of header, default signature>

Will generate header:

signature: Murano <Murano Key>:<signature>

See our complete example.

The <signature> is built as follow:

<signature> = Base64(RSA-SHA256(<host header><url (path with query parameter)><x-exosite-tracking-id header><date header><content-length header, if any>))

Server example:

First you will need to get the Murano public certificate and in order to be called from Murano the service needs a service valid certificate.

const {createServer} = require('https');
const {readFileSync} = require('fs');
const {readCertificateInfo} = require('pem');
const {verify, createPublicKey} = require('crypto');

const key = readFileSync('./server.key.pem');
const cert = readFileSync('./server.cert.pem');
const muranoCa = readFileSync('./murano-services-api-cert.pem');

const clientCertificates = { };
readCertificateInfo(muranoCa, (error, {commonName, validity: {end} = {}} = {}) => {
  if (error) throw error;
  if (end < Date.now()) console.warn(`Certificate ${commonName} is expired.`);
  clientCertificates[commonName] = createPublicKey(muranoCa);
});

const signatureParser = /^Murano (?<keyId>[\w.-]+):(?<signature>[\w/+=]+)$/;
function verifyMurano ({url, headers: {signature: signHeader, host, 'x-exosite-tracking-id': trackingId, date, 'content-length': size = ''}}) {
  if (!signHeader || !trackingId || !date) return false;
  let {groups: {keyId, signature} = {}} = signHeader.match(signatureParser) || {};
  const publicKey = clientCertificates[keyId];

  if (!publicKey || !signature) return console.log("Failed to parse " + signHeader);

  const data = Buffer.from(host + url + trackingId + date + size);
  return verify(null, data, publicKey, Buffer.from(signature, 'base64')) && keyId || console.log("Failed to verify: " + host + url + trackingId + date + size);
}

createServer({key, cert}, (req, res) => {
  res.statusCode = 401;
  const identity = verifyMurano(req);
  if (identity) {
    res.statusCode = 200;
    console.log('Welcome ' + identity);
  }
  res.end();
}).listen(8000);
ClientCA

Validating request from murano using client certificate.

Example:

type: clientCA

See our complete example.

Server example:

First you will need to get the Murano public certificate and in order to be called from Murano the service needs a service valid certificate.

const {createServer} = require('https');
const {readFileSync} = require('fs');

createServer({
  key: readFileSync('./server.key.pem'),
  cert: readFileSync('./server.cert.pem'),
  ca: readFileSync('./murano-services-api-cert.pem'),
  requestCert: true,
  rejectUnauthorized: false
}, (req, res) => {
  res.statusCode = 401;
  if (req.client.authorized) {
    res.statusCode = 200;
    console.log('Welcome ' + req.socket.getPeerCertificate().subject.CN);
  }
  return res.end();
}).listen(8000);

Config Parameters Object

An array of parameters (JSON schema) defining the data set in the service Configuration parameters field for this serviceconfig.

Service configuration parameters allow user to set static values for the service. Murano services page will display dynamically generated forms based on this configuration.
Those parameters can be used used in 2 ways:

  1. Provide default value for Lua script calls to avoid user to explicitly set static configuration like credentials from the scripting environment.
  2. Service initialization. Parameters can be transmitted during service lifecycle events such as ‘x-exosite-init’ or ‘x-exosite-update’ to set user settings within the service.
Required Fields
Field Pattern Type Example Description
name string domain The name of the configuration parameter.
description string Something description A brief description of the configuration parameter.
type string string The type of the configuration parameter.
Optional Fields
Field Pattern Type Example Description
x-exosite-hidden boolean false Declares this configuration parameter to be hidden or not.
x-exosite-restricted boolean false If set to true: prevent this parameter to be filled by user.

For example, this option is used to restrict the parameter value to an internally provided value like "solution_id".
x-exosite-from domain / solution_id / business_id domain / solution_id / business_id Populate this parameter from a user context value.
This option is generally used along with "x-exosite-restricted: true" to prevent user for overriding his context and potentially accessing other user data.
required boolean false Determines whether this configuration parameter is mandatory for the service to be usable from Murano scripting.
format string password Set to password format for obscuring the sensitive data like password and secret token. The real data will not be returned from backend.
encrypt boolean true Determines if the configuration parameter is encrypted before storing in the database or if it is stored as cleartext.

Example - Dark Sky Weather Service Integration

As an example service please take a look at this small Dark Sky weather service integration: https://github.com/exosite/darksky_service/blob/master/darksky.yaml. Notice that the service specification has four main sections.

API Information

This Sections includes a summary of the integration along with attendant information about where more information can be found what format and encoding expectations a consumer of this service should expect.

info:
  version:      "0.2"
  title:        Dark Sky Weather Service Integration
  description:  |
                ## Use Dark Sky to get weather forecasts and historical weather data.
                This is a Murano Service integration with
                [Dark Sky](https://darksky.net) to allow your Murano solution
                to get weather forecasts and historical weather data. [Powered by Dark Sky](https://darksky.net/poweredby/)
  contact:
    name:       Exosite Support
    email:      [email protected]

Service Configuration Parameters

This is a special section Exosite extended from Swagger to make service configurations available through the Murano UI. Services like this Dark Sky service need to be configured with an API token in order to function.

x-exosite-config-parameters:
  - name:         auth_token
    description:  Dark Sky Authentication Token
    type:         string
    format:       password
    required:     true

Paths

This is the real body of the service specification where the endpoints of the Dark Sky service are defined and combined into a Murano solution scripting environment operation.

paths:
  /{auth_token}/{lat_and_long_or_time}:

    > parameters:

    get:
      tags:
        - calls
      operationId:  forecast
      summary:      Make a request to Dark Sky
      description:  Fetch a weather forecast or get historical weather data based of input latitude and longitude
      x-exosite-example:    


                    --#ENDPOINT GET /darksky/weather
                    weather_data = Darksky.forecast({lat_and_long_or_time = '44.977753,93.265011'})
      > parameters:

Definitions

The definitions section can be used by reference objects in order re-use specification code. If elements of the spec are copied and pasted more than once, they can be set here and reused.

Define a Token to Access Dispatcher

We allow services, which are published on Exosite Marketplace, to access dispatcher APIs using a security Token as defined in below steps.

Step 1: define x-exosite-token

In schema, add a attribute called x-exosite-token, the value needs to be a secure token provided when accessing the Murano Service API.

An example (refer to this minimalservice.yaml):

# ...
################################################################################
#                            API Information                                   #
################################################################################
# ...
x-exosite-token: "myprivatetoken"
# ...

Once the service swagger has been published and processed, the token will be removed and will not be accessible from Murano anymore. So you MUST keep it securely saved. If you forget it you can overload the current token by updating the service swagger definition.

Step 2: call dispatcher

Add the authorization header with value <service alias> <token value> (Example: authorization: minimalservice myprivatetoken) for all calls to the Murano Service API endpoints.

  • 2.1 call Event Trigger

    base_url = https://service-api.hosted.exosite.io

    GET/POST <base_url>/api/v1/trigger/:context_id/:service_alias/:event_type

    • context_id: the solution_id
    • service_alias: which service you want to call, eg: tsdb
    • event_type: which event to call, eg: export

  • 2.2 call Service Logs / Metrics

    GET/POST <base_url>/ws/service/:service/log

    GET/POST <base_url>/ws/service/:service/metric/:metric

    If you want to use metric, please remember to define the x-exosite-usage-metrics along with x-exosite-token, if you don't define this, your connection to the metric endpoint will get rejected.

    An example of metrics definition:

    x-exosite-usage-metrics:
  bandwidth:
    name: Data size downloaded
    description: The number of bytes downloaded over a calendar month by devices of this product.
    type: counter
    unit: byte
    categories:
      in: Data uploaded
      out: Data downloaded
  size:
    name: Data size stored
    description: The number of bytes stored for this product.
    type: gauge
    unit: byte

About

Use Open-API swagger format to publish Murano Exchange services.

docs.exosite.com/reference/ui/exchange/authoring-elements-guide/#openapi-integration-service

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