chore: move 'elastic-apm-http-client' package code into this repo (elastic#3507)

This moves the apm-nodejs-http-client.git code into 
"{lib,test}/apm-client/http-apm-client/..." in this repo. This will
help maintenance of multiple active branches of the APM agent.

The only changes are to rename the export to `HttpApmClient` and adjust
require paths. Some functions were moved from lib/apm-client/http-apm-client.js
to lib/apm-client/apm-client.js to clarify.

Closes: elastic#3506
Co-authored-by: Trent Mick <[email protected]>

Author: 2 people

CHANGELOG.asciidoc

@@ -53,6 +53,9 @@ Notes:
 [float]
 ===== Chores
 
+* Inline the `elastic-apm-http-client` package code into this repo.
+  ({issues}3506[#3506])
+
 
 [[release-notes-3.48.0]]
 ==== 3.48.0 - 2023/07/07

NOTICE.md

@@ -41,6 +41,26 @@ OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 ```
 
+## container-info
+
+- **path:** [lib/container-info.js](lib/container-info.js)
+- **author:** Stephen Belanger
+- **project url:** https://github.com/Qard/container-info
+- **original file:** https://github.com/Qard/container-info/blob/master/index.js
+- **license:** MIT License (MIT), http://opensource.org/licenses/MIT
+
+```
+### Copyright (c) 2018 Stephen Belanger
+
+#### Licensed under MIT License
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+```
+
 ## shimmer
 
 - **path:** [lib/instrumentation/shimmer.js](lib/instrumentation/shimmer.js)

lib/apm-client/apm-client.js

@@ -6,14 +6,17 @@
 
 'use strict'
 
-const ElasticAPMHttpClient = require('elastic-apm-http-client')
-
-const { CENTRAL_CONFIG_OPTS } = require('../config/schema')
+const fs = require('fs')
+const version = require('../../package').version
+const { CENTRAL_CONFIG_OPTS, INTAKE_STRING_MAX_SIZE } = require('../config/schema')
 const { normalize } = require('../config/config')
+const { CloudMetadata } = require('../cloud-metadata')
+const { isLambdaExecutionEnvironment } = require('../lambda')
 const logging = require('../logging')
 
+const { HttpApmClient } = require('./http-apm-client')
 const { NoopApmClient } = require('./noop-apm-client')
-const { getHttpClientConfig } = require('./http-apm-client')
+const { isAzureFunctionsEnvironment, getAzureFunctionsExtraMetadata } = require('../instrumentation/azure-functions')
 
 /**
  * Returns an APM client suited for the configuration provided
@@ -28,7 +31,7 @@ function createApmClient (config, agent) {
     return config.transport(config, agent)
   }
 
-  const client = new ElasticAPMHttpClient(getHttpClientConfig(config, agent))
+  const client = new HttpApmClient(getHttpClientConfig(config, agent))
 
   client.on('config', remoteConf => {
     agent.logger.debug({ remoteConf }, 'central config received')
@@ -104,6 +107,171 @@ function createApmClient (config, agent) {
   return client
 }
 
+/**
+ * Returns a HTTP client configuration based on agent configuration options
+ *
+ * @param {Object} conf The agent configuration object
+ * @param {Object} agent
+ * @returns {Object}
+ */
+function getHttpClientConfig (conf, agent) {
+  let clientLogger = null
+  if (!logging.isLoggerCustom(agent.logger)) {
+    // https://www.elastic.co/guide/en/ecs/current/ecs-event.html#field-event-module
+    clientLogger = agent.logger.child({ 'event.module': 'apmclient' })
+  }
+  const isLambda = isLambdaExecutionEnvironment()
+
+  const clientConfig = {
+    agentName: 'nodejs',
+    agentVersion: version,
+    agentActivationMethod: agent._agentActivationMethod,
+    serviceName: conf.serviceName,
+    serviceVersion: conf.serviceVersion,
+    frameworkName: conf.frameworkName,
+    frameworkVersion: conf.frameworkVersion,
+    globalLabels: maybePairsToObject(conf.globalLabels),
+    configuredHostname: conf.hostname,
+    environment: conf.environment,
+
+    // Sanitize conf
+    truncateKeywordsAt: INTAKE_STRING_MAX_SIZE,
+    truncateLongFieldsAt: conf.longFieldMaxLength,
+    // truncateErrorMessagesAt: see below
+
+    // HTTP conf
+    secretToken: conf.secretToken,
+    apiKey: conf.apiKey,
+    userAgent: userAgentFromConf(conf),
+    serverUrl: conf.serverUrl,
+    serverCaCert: loadServerCaCertFile(conf.serverCaCertFile),
+    rejectUnauthorized: conf.verifyServerCert,
+    serverTimeout: conf.serverTimeout * 1000,
+
+    // APM Agent Configuration via Kibana:
+    centralConfig: conf.centralConfig,
+
+    // Streaming conf
+    size: conf.apiRequestSize,
+    time: conf.apiRequestTime * 1000,
+    maxQueueSize: conf.maxQueueSize,
+
+    // Debugging/testing options
+    logger: clientLogger,
+    payloadLogFile: conf.payloadLogFile,
+    apmServerVersion: conf.apmServerVersion,
+
+    // Container conf
+    containerId: conf.containerId,
+    kubernetesNodeName: conf.kubernetesNodeName,
+    kubernetesNamespace: conf.kubernetesNamespace,
+    kubernetesPodName: conf.kubernetesPodName,
+    kubernetesPodUID: conf.kubernetesPodUID
+  }
+
+  // `service_node_name` is ignored in Lambda and Azure Functions envs.
+  if (conf.serviceNodeName) {
+    if (isLambda) {
+      agent.logger.warn({ serviceNodeName: conf.serviceNodeName }, 'ignoring "serviceNodeName" config setting in Lambda environment')
+    } else if (isAzureFunctionsEnvironment) {
+      agent.logger.warn({ serviceNodeName: conf.serviceNodeName }, 'ignoring "serviceNodeName" config setting in Azure Functions environment')
+    } else {
+      clientConfig.serviceNodeName = conf.serviceNodeName
+    }
+  }
+
+  // Extra metadata handling.
+  if (isLambda) {
+    // Tell the Client to wait for a subsequent `.setExtraMetadata()` call
+    // before allowing intake requests. This will be called by `apm.lambda()`
+    // on first Lambda function invocation.
+    clientConfig.expectExtraMetadata = true
+  } else if (isAzureFunctionsEnvironment) {
+    clientConfig.extraMetadata = getAzureFunctionsExtraMetadata()
+  } else if (conf.cloudProvider !== 'none') {
+    clientConfig.cloudMetadataFetcher = new CloudMetadata(conf.cloudProvider, conf.logger, conf.serviceName)
+  }
+
+  if (conf.errorMessageMaxLength !== undefined) {
+    // As of v10 of the http client, truncation of error messages will default
+    // to `truncateLongFieldsAt` if `truncateErrorMessagesAt` is not specified.
+    clientConfig.truncateErrorMessagesAt = conf.errorMessageMaxLength
+  }
+
+  return clientConfig
+}
+
+// Return the User-Agent string the agent will use for its comms to APM Server.
+//
+// Per https://github.com/elastic/apm/blob/main/specs/agents/transport.md#user-agent
+// the pattern is roughly this:
+//    $repoName/$version ($serviceName $serviceVersion)
+//
+// The format of User-Agent is governed by https://datatracker.ietf.org/doc/html/rfc7231.
+//    User-Agent = product *( RWS ( product / comment ) )
+// We do not expect `$repoName` and `$version` to have surprise/invalid values.
+// From `validateServiceName` above, we know that `$serviceName` is null or a
+// string limited to `/^[a-zA-Z0-9 _-]+$/`. However, `$serviceVersion` is
+// provided by the user and could have invalid characters.
+//
+// `comment` is defined by
+// https://datatracker.ietf.org/doc/html/rfc7230#section-3.2.6 as:
+//    comment        = "(" *( ctext / quoted-pair / comment ) ")"
+//    obs-text       = %x80-FF
+//    ctext          = HTAB / SP / %x21-27 / %x2A-5B / %x5D-7E / obs-text
+//    quoted-pair    = "\" ( HTAB / SP / VCHAR / obs-text )
+//
+// `commentBadChar` below *approximates* these rules, and is used to replace
+// invalid characters with '_' in the generated User-Agent string. This
+// replacement isn't part of the APM spec.
+function userAgentFromConf (conf) {
+  let userAgent = `apm-agent-nodejs/${version}`
+
+  // This regex *approximately* matches the allowed syntax for a "comment".
+  // It does not handle "quoted-pair" or a "comment" in a comment.
+  const commentBadChar = /[^\t \x21-\x27\x2a-\x5b\x5d-\x7e\x80-\xff]/g
+  const commentParts = []
+  if (conf.serviceName) {
+    commentParts.push(conf.serviceName)
+  }
+  if (conf.serviceVersion) {
+    commentParts.push(conf.serviceVersion.replace(commentBadChar, '_'))
+  }
+  if (commentParts.length > 0) {
+    userAgent += ` (${commentParts.join(' ')})`
+  }
+
+  return userAgent
+}
+
+/**
+ * Reads te server CA cert file and returns a buffer with its contents
+ * @param {string | undefined} serverCaCertFile
+ * @param {any} logger
+ * @returns {Buffer}
+ */
+function loadServerCaCertFile (serverCaCertFile, logger) {
+  if (serverCaCertFile) {
+    try {
+      return fs.readFileSync(serverCaCertFile)
+    } catch (err) {
+      logger.error('Elastic APM initialization error: Can\'t read server CA cert file %s (%s)', serverCaCertFile, err.message)
+    }
+  }
+}
+
+function maybePairsToObject (pairs) {
+  return pairs ? pairsToObject(pairs) : undefined
+}
+
+function pairsToObject (pairs) {
+  return pairs.reduce((object, [key, value]) => {
+    object[key] = value
+    return object
+  }, {})
+}
+
 module.exports = {
-  createApmClient
+  createApmClient,
+  userAgentFromConf
 }