fastify-cloudevents
Version:
Fastify Plugin to serialize events in the CloudEvents standard format
238 lines (225 loc) • 7.86 kB
JavaScript
/*
* Copyright 2018-2022 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* Builder:
* Utility module to export builder functions useful for creating
* values (grouped or not) to use in Cloudevents.
* Should not be used outside of the plugin.
* @module utility
*/
/**
* Get a reference to CloudEvent class definition and related utilities.
* See {@link CloudEvent}.
* @private
*/
const { CloudEvent, CloudEventTransformer } = require('cloudevent')
/**
* Utility function for creating grouped values to use in Cloudevents.
* Should not be used outside of the plugin.
*
* @param {!object} options configuration options
* @return {object} an object with builder functions (configured) to use
* @private
*/
function builder (options = {}) {
const {
pluginName,
pluginVersion,
serverUrl,
serverUrlMode,
baseNamespace,
idGenerator,
includeHeaders,
includeRedundantAttributes,
cloudEventOptions,
cloudEventExtensions
} = options
return {
/**
* Build the value for the source field of the CloudEvent,
* depending on the plugin configuration of options
* `serverUrlMode`, `serverUrl`,
* and the uri part of the current request.
* Note that this is mainly for usage inside the plugin,
* but in some cases could be useful even outside.
*
* @param {string} [url=''] the uri part of the current request
* @return {string} the source value to use, as a string
* @private
*/
buildSourceUrl (url = '') {
let sourceUrl
switch (serverUrlMode) {
case null:
case 'pluginAndRequestSimplified':
sourceUrl = serverUrl + CloudEventTransformer.uriStripArguments(url)
break
case 'pluginAndRequestUrl':
sourceUrl = serverUrl + url
break
case 'pluginServerUrl':
sourceUrl = serverUrl
break
case 'requestUrl':
sourceUrl = url
break
default:
throw new Error(`Illegal value for serverUrlMode: '${serverUrlMode}'`)
}
return sourceUrl
},
/**
* Extract and build the value for the client IP address,
* useful to add into the CloudEvent in a custom attribute inside data,
* otherwise nothing.
*
* @param {!object} request the request
* @return {string} the IP address, as a string or undefined
* @private
*/
buildClientIP (request) {
if (request === undefined || request === null) {
throw new Error('Illegal value for request: undefined or null')
}
return request.ip || undefined
},
/**
* Extract and build the value for the HTTP headers,
* useful to add into the CloudEvent in a custom attribute inside data.
* If plugin flag 'includeHeaders' is enabled, headers will be returned,
* otherwise nothing.
* Note that some config options for builders are used here.
*
* @param {!object} request the request
* @return {string} HTTP request headers, as a string, or undefined
* @private
*/
buildHeaders (request) {
if (request === undefined || request === null) {
throw new Error('Illegal value for request: undefined or null')
}
const headers = (includeHeaders === null || includeHeaders === false) ? undefined : request.headers
return headers
},
/**
* Extract and build values from the given arguments,
* and returns them inside a wrapper object.
*
* @param {!object} request the request
* @return {object} an object containing headers, source URL, the IP address
* @private
*/
buildValues (request) {
const clientIp = this.buildClientIP(request)
const headers = this.buildHeaders(request)
const sourceUrl = this.buildSourceUrl(request.raw.url)
return { clientIp, headers, sourceUrl }
},
/**
* Extract some values from the given arguments,
* and returns them inside a wrapper object
* to be used in a CloudEvent data (sub-)property.
*
* @param {!object} request the request
* @return {object} an object containing extracted attributes
* @private
*/
buildRequestDataForCE (request) {
return {
id: request.id,
headers: this.buildHeaders(request),
clientIp: this.buildClientIP(request),
params: request.params,
query: request.query,
body: request.body,
method: request.raw.method,
url: request.raw.url
}
},
/**
* Extract some values from the given arguments,
* and returns them inside a wrapper object
* to be used in a CloudEvent data (sub-)property.
*
* @param {!object} reply the reply
* @return {object} an object containing extracted attributes
* @private
*/
buildReplyDataForCE (reply) {
return {
statusCode: reply.raw.statusCode,
statusMessage: reply.raw.statusMessage,
finished: reply.raw.finished
}
},
/**
* Extract some values from the given arguments,
* and returns them inside a wrapper object
* to be used in a CloudEvent data (sub-)property.
* Note that some config options for builders are used here.
*
* @param {object} [description=''] the description (maybe related to the event)
* @return {object} an object containing extracted attributes
* @private
*/
buildPluginDataForCE (description = '') {
return {
timestamp: CloudEventTransformer.timestampToNumber(),
description,
name: pluginName,
version: pluginVersion
}
},
/**
* Build a CloudEvent instance from the given arguments,
* useful for simplify plugin hooks.
* If plugin flag 'includeRedundantAttributes' is enabled,
* some redundant attributes will be added to data.
* Note that some config options for builders are used here.
*
* @param {!string} hookName the name of the hook
* @param {!object} request the request
* @param {object} reply the reply
* @param {object} payload the payload
* @return {object} the CloudEvent instance
* @private
*/
buildCloudEventForHook (hookName, request, reply, payload) {
if (!hookName || !request) {
throw new Error('Illegal arguments: mandatory argument undefined or null')
}
const ceData = {
request: this.buildRequestDataForCE(request),
reply: (reply === null) ? undefined : this.buildReplyDataForCE(reply),
payload
}
if (includeRedundantAttributes !== null && includeRedundantAttributes === true) {
ceData.id = request.id
ceData.timestamp = CloudEventTransformer.timestampToNumber()
}
const ce = new CloudEvent(idGenerator.next().value,
`${baseNamespace}.${hookName}`,
this.buildSourceUrl(request.raw.url),
ceData,
cloudEventOptions,
cloudEventExtensions
)
return ce
}
}
}
module.exports = builder