{"version":3,"file":"utils.js","sources":["../../../../src/transports/utils.ts"],"sourcesContent":["import { isNativeFetch, logger } from '@sentry/utils';\n\nimport { WINDOW } from '../helpers';\n\nlet cachedFetchImpl: FetchImpl | undefined = undefined;\n\nexport type FetchImpl = typeof fetch;\n\n/**\n * A special usecase for incorrectly wrapped Fetch APIs in conjunction with ad-blockers.\n * Whenever someone wraps the Fetch API and returns the wrong promise chain,\n * this chain becomes orphaned and there is no possible way to capture it's rejections\n * other than allowing it bubble up to this very handler. eg.\n *\n * const f = window.fetch;\n * window.fetch = function () {\n *   const p = f.apply(this, arguments);\n *\n *   p.then(function() {\n *     console.log('hi.');\n *   });\n *\n *   return p;\n * }\n *\n * `p.then(function () { ... })` is producing a completely separate promise chain,\n * however, what's returned is `p` - the result of original `fetch` call.\n *\n * This mean, that whenever we use the Fetch API to send our own requests, _and_\n * some ad-blocker blocks it, this orphaned chain will _always_ reject,\n * effectively causing another event to be captured.\n * This makes a whole process become an infinite loop, which we need to somehow\n * deal with, and break it in one way or another.\n *\n * To deal with this issue, we are making sure that we _always_ use the real\n * browser Fetch API, instead of relying on what `window.fetch` exposes.\n * The only downside to this would be missing our own requests as breadcrumbs,\n * but because we are already not doing this, it should be just fine.\n *\n * Possible failed fetch error messages per-browser:\n *\n * Chrome:  Failed to fetch\n * Edge:    Failed to Fetch\n * Firefox: NetworkError when attempting to fetch resource\n * Safari:  resource blocked by content blocker\n */\nexport function getNativeFetchImplementation(): FetchImpl {\n  if (cachedFetchImpl) {\n    return cachedFetchImpl;\n  }\n\n  /* eslint-disable @typescript-eslint/unbound-method */\n\n  // Fast path to avoid DOM I/O\n  if (isNativeFetch(WINDOW.fetch)) {\n    return (cachedFetchImpl = WINDOW.fetch.bind(WINDOW));\n  }\n\n  const document = WINDOW.document;\n  let fetchImpl = WINDOW.fetch;\n  // eslint-disable-next-line deprecation/deprecation\n  if (document && typeof document.createElement === 'function') {\n    try {\n      const sandbox = document.createElement('iframe');\n      sandbox.hidden = true;\n      document.head.appendChild(sandbox);\n      const contentWindow = sandbox.contentWindow;\n      if (contentWindow && contentWindow.fetch) {\n        fetchImpl = contentWindow.fetch;\n      }\n      document.head.removeChild(sandbox);\n    } catch (e) {\n      __DEBUG_BUILD__ &&\n        logger.warn('Could not create sandbox iframe for pure fetch check, bailing to window.fetch: ', e);\n    }\n  }\n\n  return (cachedFetchImpl = fetchImpl.bind(WINDOW));\n  /* eslint-enable @typescript-eslint/unbound-method */\n}\n\n/** Clears cached fetch impl */\nexport function clearCachedFetchImplementation(): void {\n  cachedFetchImpl = undefined;\n}\n"],"names":[],"mappings":";;;AAIA,IAAA,eAAA,GAAA,SAAA,CAAA;;AAIA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA;AACA,SAAA,4BAAA,GAAA;AACA,EAAA,IAAA,eAAA,EAAA;AACA,IAAA,OAAA,eAAA,CAAA;AACA,GAAA;AACA;AACA;AACA;AACA;AACA,EAAA,IAAA,aAAA,CAAA,MAAA,CAAA,KAAA,CAAA,EAAA;AACA,IAAA,QAAA,eAAA,GAAA,MAAA,CAAA,KAAA,CAAA,IAAA,CAAA,MAAA,CAAA,EAAA;AACA,GAAA;AACA;AACA,EAAA,MAAA,QAAA,GAAA,MAAA,CAAA,QAAA,CAAA;AACA,EAAA,IAAA,SAAA,GAAA,MAAA,CAAA,KAAA,CAAA;AACA;AACA,EAAA,IAAA,QAAA,IAAA,OAAA,QAAA,CAAA,aAAA,KAAA,UAAA,EAAA;AACA,IAAA,IAAA;AACA,MAAA,MAAA,OAAA,GAAA,QAAA,CAAA,aAAA,CAAA,QAAA,CAAA,CAAA;AACA,MAAA,OAAA,CAAA,MAAA,GAAA,IAAA,CAAA;AACA,MAAA,QAAA,CAAA,IAAA,CAAA,WAAA,CAAA,OAAA,CAAA,CAAA;AACA,MAAA,MAAA,aAAA,GAAA,OAAA,CAAA,aAAA,CAAA;AACA,MAAA,IAAA,aAAA,IAAA,aAAA,CAAA,KAAA,EAAA;AACA,QAAA,SAAA,GAAA,aAAA,CAAA,KAAA,CAAA;AACA,OAAA;AACA,MAAA,QAAA,CAAA,IAAA,CAAA,WAAA,CAAA,OAAA,CAAA,CAAA;AACA,KAAA,CAAA,OAAA,CAAA,EAAA;AACA,MAAA,CAAA,OAAA,gBAAA,KAAA,WAAA,IAAA,gBAAA;AACA,QAAA,MAAA,CAAA,IAAA,CAAA,iFAAA,EAAA,CAAA,CAAA,CAAA;AACA,KAAA;AACA,GAAA;AACA;AACA,EAAA,QAAA,eAAA,GAAA,SAAA,CAAA,IAAA,CAAA,MAAA,CAAA,EAAA;AACA;AACA,CAAA;AACA;AACA;AACA,SAAA,8BAAA,GAAA;AACA,EAAA,eAAA,GAAA,SAAA,CAAA;AACA;;;;"}