Perf Counters exposed as environment variables

The following are 'fake' Environment Variables that don't exist if you enumerate them, but return their value if you look them up individually. The value is dynamic and can change on every lookup.

• WEBSITE_COUNTERS_ASPNET - Returns a JSON object containing the ASP.NET perf counters.
• WEBSITE_COUNTERS_APP - Returns a JSON object containing sandbox counters.
• WEBSITE_COUNTERS_CLR - Returns a JSON object containing CLR counters.
• WEBSITE_COUNTERS_ALL - Returns a JSON object containing the combination of the other three.

Here is an example of what you would get by evaluating WEBSITE_COUNTERS_ALL:

{
  "aspNet": {
    "applicationRestarts": 0,
    "applicationsRunning": 0,
    "requestsDisconnected": 0,
    "requestExecutionTime": 0,
    "requestsRejected": 0,
    "requestsQueued": 0,
    "wpsRunning": 0,
    "wpsRestarts": 0,
    "requestWaitTime": 0,
    "requestsCurrent": 0,
    "globalAuditSuccess": 0,
    "globalAuditFail": 0,
    "globalEventsError": 0,
    "globalEventsHttpReqError": 0,
    "globalEventsHttpInfraError": 0,
    "requestsInNativeQueue": 0,
    "anonymousRequests": 0,
    "totalCacheEntries": 0,
    "totalCacheTurnoverRate": 0,
    "totalCacheHits": 0,
    "totalCacheMisses": 0,
    "totalCacheRatioBase": 0,
    "apiCacheEntries": 0,
    "apiCacheTurnoverRate": 0,
    "apiCacheHits": 0,
    "apiCacheMisses": 0,
    "apiCacheRatioBase": 0,
    "outputCacheEntries": 0,
    "outputCacheTurnoverRate": 0,
    "outputCacheHits": 0,
    "outputCacheMisses": 0,
    "outputCacheRatioBase": 0,
    "compilations": 0,
    "debuggingRequests": 0,
    "errorsPreProcessing": 0,
    "errorsCompiling": 0,
    "errorsDuringRequest": 0,
    "errorsUnhandled": 0,
    "errorsTotal": 0,
    "pipelines": 0,
    "requestBytesIn": 0,
    "requestBytesOut": 0,
    "requestsExecuting": 0,
    "requestsFailed": 0,
    "requestsNotFound": 0,
    "requestsNotAuthorized": 0,
    "requestsInApplicationQueue": 0,
    "requestsTimedOut": 0,
    "requestsSucceded": 0,
    "requestsTotal": 0,
    "sessionsActive": 0,
    "sessionsAbandoned": 0,
    "sessionsTimedOut": 0,
    "sessionsTotal": 0,
    "transactionsAborted": 0,
    "transactionsCommitted": 0,
    "transactionsPending": 0,
    "transactionsTotal": 0,
    "sessionStateServerConnections": 0,
    "sessionSqlServerConnections": 0,
    "eventsTotal": 0,
    "eventsApp": 0,
    "eventsError": 0,
    "eventsHttpReqError": 0,
    "eventsHttpInfraError": 0,
    "eventsWebReq": 0,
    "auditSuccess": 0,
    "auditFail": 0,
    "memberSuccess": 0,
    "memberFail": 0,
    "formsAuthSuccess": 0,
    "formsAuthFail": 0,
    "viewstateMacFail": 0,
    "appRequestExecTime": 0,
    "appRequestDisconnected": 0,
    "appRequestsRejected": 0,
    "appRequestWaitTime": 0,
    "cachePercentMachMemLimitUsed": 0,
    "cachePercentMachMemLimitUsedBase": 0,
    "cachePercentProcMemLimitUsed": 0,
    "cachePercentProcMemLimitUsedBase": 0,
    "cacheTotalTrims": 0,
    "cacheApiTrims": 0,
    "cacheOutputTrims": 0,
    "appCpuUsed": 0,
    "appCpuUsedBase": 0,
    "appMemoryUsed": 0,
    "requestBytesInWebsockets": 0,
    "requestBytesOutWebsockets": 0,
    "requestsExecutingWebsockets": 0,
    "requestsFailedWebsockets": 0,
    "requestsSucceededWebsockets": 0,
    "requestsTotalWebsockets": 0
  },
  "app": {
    "userTime": 65625000,
    "kernelTime": 38750000,
    "pageFaults": 175585,
    "processes": 2,
    "processLimit": 32,
    "threads": 37,
    "threadLimit": 512,
    "connections": 0,
    "connectionLimit": 300,
    "sections": 3,
    "sectionLimit": 256,
    "namedPipes": 2,
    "namedPipeLimit": 128,
    "readIoOperations": 2485,
    "writeIoOperations": 859,
    "otherIoOperations": 38155,
    "readIoBytes": 7715020,
    "writeIoBytes": 5850202,
    "otherIoBytes": 1899661,
    "privateBytes": 19206144,
    "handles": 2408,
    "contextSwitches": 365042,
    "remoteOpens": 3196,
    "remoteWrites": 47,
    "remoteWriteKBs": 952
  },
  "clr": {
    "bytesInAllHeaps": 0,
    "gcHandles": 0,
    "gen0Collections": 0,
    "gen1Collections": 0,
    "gen2Collections": 0,
    "inducedGC": 0,
    "pinnedObjects": 0,
    "committedBytes": 0,
    "reservedBytes": 0,
    "timeInGC": 0,
    "timeInGCBase": 0,
    "allocatedBytes": 0,
    "gen0HeapSize": 0,
    "gen1HeapSize": 0,
    "gen2HeapSize": 0,
    "largeObjectHeapSize": 0,
    "currentAssemblies": 0,
    "currentClassesLoaded": 0,
    "exceptionsThrown": 0,
    "appDomains": 0,
    "appDomainsUnloaded": 0
  }
}