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iisnode web.config reference

Nabil Redmann edited this page May 3, 2021 · 1 revision
<configuration>
  <system.webServer>

    <!-- indicates that the hello.js file is a node.js application 
    to be handled by the iisnode module -->

    <handlers>
      <add name="iisnode" path="hello.js" verb="*" modules="iisnode" />
    </handlers>

    <!-- 
      the iisnode section configures the behavior of the node.js IIS module 
      setting values below are defaults
    
    * node_env - determines the environment (production, development, staging, ...) in which 
      child node processes run; if nonempty, is propagated to the child node processes as their NODE_ENV
      environment variable; the default is the value of the IIS worker process'es NODE_ENV
      environment variable

    * nodeProcessCommandLine - command line starting the node executable; in shared
      hosting environments this setting would typically be locked at the machine scope.

    * interceptor - fully qualified file name of a node.js application that will run instead of an actual application
      the request targets; the fully qualified file name of the actual application file is provided as the first parameter
      to the interceptor application; default interceptor supports iisnode logging
      
    * nodeProcessCountPerApplication - number of node.exe processes that IIS will start per application;
      setting this value to 0 results in creating one node.exe process per each processor on the machine
      
    * maxConcurrentRequestsPerProcess - maximum number of reqeusts one node process can 
      handle at a time
      
    * maxNamedPipeConnectionRetry - number of times IIS will retry to establish a named pipe connection with a
      node process in order to send a new HTTP request
      
    * namedPipeConnectionRetryDelay - delay in milliseconds between connection retries

    * maxNamedPipeConnectionPoolSize - maximum number of named pipe connections that will be kept in a connection pool; 
      connection pooling helps improve the performance of applications that process a large number of short lived HTTP requests
      
    * maxNamedPipePooledConnectionAge - age of a pooled connection in milliseconds after which the connection is not reused for
      subsequent requests
    
    * asyncCompletionThreadCount - size of the IO thread pool maintained by the IIS module to process asynchronous IO; setting it
      to 0 (default) results in creating one thread per each processor on the machine
    
    * initialRequestBufferSize - initial size in bytes of a memory buffer allocated for a new HTTP request
    
    * maxRequestBufferSize - maximum size in bytes of a memory buffer allocated per request; this is a hard limit of 
      the serialized form of HTTP request or response headers block

    * watchedFiles - semi-colon separated list of files that will be watched for changes; a change to a file causes the application to recycle;
      each entry consists of an optional directory name plus required file name which are relative to the directory where the main application entry point 
      is located; wild cards are allowed in the file name portion only; for example: "*.js;node_modules\foo\lib\options.json;app_data\*.config.json"
      
    * uncFileChangesPollingInterval - applications are recycled when the underlying *.js file is modified; if the file resides
      on a UNC share, the only reliable way to detect such modifications is to periodically poll for them; this setting 
      controls the polling interval
      
    * gracefulShutdownTimeout - when a node.js file is modified, all node processes handling running this application are recycled;
      this setting controls the time (in milliseconds) given for currently active requests to gracefully finish before the 
      process is terminated; during this time, all new requests are already dispatched to a new node process based on the fresh version 
      of the application
    
    * loggingEnabled - controls whether stdout and stderr streams from node processes are captured and made available over HTTP
    
    * logDirectory - directory name relative to the main application file that will store files with stdout and stderr captures; 
      individual log file names have unique file names; log files are created lazily (i.e. when the process actually writes something
      to stdout or stderr); an HTML index of all log files is also maintained as index.html in that directory;
      by default, if your application is at http://foo.com/bar.js, logs will be accessible at http://foo.com/iisnode;
      SECURITY NOTE: if log files contain sensitive information, this setting should be modified to contain enough entropy to be considered
      cryptographically secure; in most situations, a GUID is sufficient
      
    * debuggingEnabled - controls whether the built-in debugger is available
      
    * debuggerPortRange - range of TCP ports that can be used for communication between the node-inspector debugger and the debugee; iisnode
      will round robin through this port range for subsequent debugging sessions and pick the next available (free) port to use from the range
      
    * debuggerPathSegment - URL path segment used to access the built-in node-inspector debugger; given a node.js application at 
      http://foo.com/bar/baz.js, the debugger can be accessed at http://foo.com/bar/baz.js/{debuggerPathSegment}, by default
      http://foo.com/bar/baz.js/debug
    
    * debugHeaderEnabled - boolean indicating whether iisnode should attach the iisnode-debug HTTP response header with 
      diagnostics information to all responses

    * maxLogFileSizeInKB - maximum size of a single log file in KB; once a log file exceeds this limit a new log file is created

    * maxTotalLogFileSizeInKB - maximum total size of all log files in the logDirectory; once exceeded, old log files are removed
    
    * maxLogFiles - maximum number of log files in the logDirectory; once exceeded, old log files are removed
    
    * devErrorsEnabled - controls how much information is sent back in the HTTP response to the browser when an error occurrs in iisnode; 
      when true, error conditions in iisnode result in HTTP 200 response with the body containing error details; when false,
      iisnode will return generic HTTP 5xx responses

    * flushResponse - controls whether each HTTP response body chunk is immediately flushed by iisnode; flushing each body chunk incurs 
      CPU cost but may improve latency in streaming scenarios

    * enableXFF - controls whether iisnode adds or modifies the X-Forwarded-For request HTTP header with the IP address of the remote host

    * promoteServerVars - comma delimited list of IIS server variables that will be propagated to the node.exe process in the form of 
      x-iisnode-<server_variable_name> HTTP request headers; for a list of IIS server variables available see 
      http://msdn.microsoft.com/en-us/library/ms524602(v=vs.90).aspx; for example "AUTH_USER,AUTH_TYPE"
      
    * configOverrides - optional file name containing overrides of configuration settings of the iisnode section of web.config; 
      the format of the file is a small subset of YAML: each setting is represented as a <key>: <value> on a separate line 
      and comments start with # until the end of the line, e.g. 
            # This is a sample iisnode.yml file
            nodeProcessCountPerApplication: 2
            maxRequestBufferSize: 8192 # increasing from the default
            # maxConcurrentRequestsPerProcess: 512 - commented out setting

    -->
    
    <iisnode      
      node_env="%node_env%"
      nodeProcessCountPerApplication="1"
      maxConcurrentRequestsPerProcess="1024"
      maxNamedPipeConnectionRetry="100"
      namedPipeConnectionRetryDelay="250"      
      maxNamedPipeConnectionPoolSize="512"
      maxNamedPipePooledConnectionAge="30000"
      asyncCompletionThreadCount="0"
      initialRequestBufferSize="4096"
      maxRequestBufferSize="65536"
      watchedFiles="*.js;node.conf"
      uncFileChangesPollingInterval="5000"
      gracefulShutdownTimeout="60000"
      loggingEnabled="true"
      logDirectory="iisnode"
      debuggingEnabled="true"
      debugHeaderEnabled="false"
      debuggerPortRange="5058-6058"
      debuggerPathSegment="debug"
      maxLogFileSizeInKB="128"
      maxTotalLogFileSizeInKB="1024"
      maxLogFiles="20"
      devErrorsEnabled="true"
      flushResponse="false"
      enableXFF="false"
      promoteServerVars=""
      configOverrides="node.conf"
     />

    <!--     
    
    One more setting that can be modified is the path to the node.exe executable:
    
    <iisnode
      nodeProcessCommandLine="&quot;%programfiles%\nodejs\node.exe&quot;" 
      interceptor="&quot;%programfiles%\iisnode\interceptor.js&quot;" />
    
    -->

    
  </system.webServer>
</configuration>
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