fix: fix sourcemap errors with node v18 (#2596)

Recent node v18 turned on an implementation of `fetch()` by default.
The 'source-map@0.7.3' dep used for sourcemap handling incorrectly
uses the presence of `fetch` to decide it is in a browser env.

This change inlines the load-source-map dep so we can update it to
use the *beta* source-map@0.8.0-beta.0 which includes a fix.

Fixes: #2589

Author: trentm

NOTICE.md

@@ -109,3 +109,33 @@ THE SOFTWARE.
 
 Parts of "lib/instrumentation/run-context" have been adapted from or influenced
 by TypeScript code in `@opentelemetry/context-async-hooks`.
+
+## load-source-map
+
+- **path:** [lib/load-source-map.js](lib/load-source-map.js)
+- **author:** Espen Hovlandsdal
+- **project url:** https://github.com/rexxars/load-source-map
+- **original file:** https://github.com/rexxars/load-source-map/blob/v2.0.0/lib/index.js
+- **license:** MIT License (MIT), http://opensource.org/licenses/MIT
+
+The MIT License (MIT)
+
+Copyright (c) 2017 Espen Hovlandsdal
+
+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.

lib/load-source-map.js

@@ -0,0 +1,84 @@
+'use strict'
+
+// This is a copy of load-source-map@2.0.0. It is inlined in elastic-apm-node
+// solely to update its `source-map` dependency to fix
+//   https://github.com/elastic/apm-agent-nodejs/issues/2589
+// If/when there is a new release of load-source-map with
+//   https://github.com/rexxars/load-source-map/pull/6
+// then we could move back to using load-source-map as a dependency.
+
+var fs = require('fs')
+var path = require('path')
+var SourceMapConsumer = require('source-map').SourceMapConsumer
+
+var INLINE_SOURCEMAP_REGEX = /^data:application\/json[^,]+base64,/
+var SOURCEMAP_REGEX = /(?:\/\/[@#][ \t]+sourceMappingURL=([^\s'"]+?)[ \t]*$)|(?:\/\*[@#][ \t]+sourceMappingURL=([^*]+?)[ \t]*(?:\*\/)[ \t]*$)/
+var READ_FILE_OPTS = { encoding: 'utf8' }
+
+module.exports = function readSourceMap (filename, cb) {
+  fs.readFile(filename, READ_FILE_OPTS, function (err, sourceFile) {
+    if (err) {
+      return cb(err)
+    }
+
+    // Look for a sourcemap URL
+    var sourceMapUrl = resolveSourceMapUrl(sourceFile, path.dirname(filename))
+    if (!sourceMapUrl) {
+      return cb()
+    }
+
+    // If it's an inline map, decode it and pass it through the same consumer factory
+    if (isInlineMap(sourceMapUrl)) {
+      return onMapRead(null, decodeInlineMap(sourceMapUrl))
+    }
+
+    // Load actual source map from given path
+    fs.readFile(sourceMapUrl, READ_FILE_OPTS, onMapRead)
+
+    function onMapRead (readErr, sourceMap) {
+      if (readErr) {
+        readErr.message = 'Error reading sourcemap for file "' + filename + '":\n' + readErr.message
+        return cb(readErr)
+      }
+
+      try {
+        (new SourceMapConsumer(sourceMap))
+          .then(function onConsumerReady (consumer) {
+            return cb(null, consumer)
+          }, onConsumerError)
+      } catch (parseErr) {
+        onConsumerError(parseErr)
+      }
+    }
+
+    function onConsumerError (parseErr) {
+      parseErr.message = 'Error parsing sourcemap for file "' + filename + '":\n' + parseErr.message
+      return cb(parseErr)
+    }
+  })
+}
+
+function resolveSourceMapUrl (sourceFile, sourcePath) {
+  var lines = sourceFile.split(/\r?\n/)
+  var sourceMapUrl = null
+  for (var i = lines.length - 1; i >= 0 && !sourceMapUrl; i--) {
+    sourceMapUrl = lines[i].match(SOURCEMAP_REGEX)
+  }
+
+  if (!sourceMapUrl) {
+    return null
+  }
+
+  return isInlineMap(sourceMapUrl[1])
+    ? sourceMapUrl[1]
+    : path.resolve(sourcePath, sourceMapUrl[1])
+}
+
+function isInlineMap (url) {
+  return INLINE_SOURCEMAP_REGEX.test(url)
+}
+
+function decodeInlineMap (data) {
+  var rawData = data.slice(data.indexOf(',') + 1)
+  return Buffer.from(rawData, 'base64').toString()
+}

lib/stacktraces.js

@@ -14,7 +14,7 @@ const asyncCache = require('async-cache')
 const afterAllResults = require('after-all-results')
 const errorCallsites = require('error-callsites')
 const errorStackParser = require('error-stack-parser')
-const loadSourceMap = require('load-source-map')
+const loadSourceMap = require('./load-source-map')
 const LRU = require('lru-cache')
 
 const fileCache = asyncCache({

package.json

@@ -94,7 +94,6 @@
     "fast-safe-stringify": "^2.0.7",
     "http-headers": "^3.0.2",
     "is-native": "^1.0.1",
-    "load-source-map": "^2.0.0",
     "lru-cache": "^6.0.0",
     "measured-reporting": "^1.51.1",
     "monitor-event-loop-delay": "^1.0.0",
@@ -108,6 +107,7 @@
     "semver": "^6.3.0",
     "set-cookie-serde": "^1.0.0",
     "shallow-clone-shim": "^2.0.0",
+    "source-map": "^0.8.0-beta.0",
     "sql-summary": "^1.0.1",
     "traceparent": "^1.0.0",
     "traverse": "^0.6.6",