shiny-express-formatter

Express Request/Response formatter

Formats requests and responses, and optionally bodies, for logging. When capturing response bodies, it only handles non-streaming requests. It is up to the app to determine what to do with the formatted objects

Example Request

{
  "id": "7d575f6b-cac9-43cc-96f2-7695f909819d",
  "headers": {
    "host": "localhost:3080",
    "connection": "keep-alive",
    "accept": "application/json, text/plain, */*",
    "user-agent": "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/47.0.2526.106 Safari/537.36",
    "referer": "http://localhost:3080/",
    "accept-encoding": "gzip, deflate, sdch",
    "accept-language": "en-US,en;q=0.8"
  },
  "method": "GET",
  "path": "/api/widgets",
  "body": {}
}

Example Response

{
  "headers": {
    "x-powered-by": "Express",
    "content-length": "24",
    "etag": "W/\"I4+1GQyv6zGcoXDQygDf+g==\""
  },
  "requestId": "7d575f6b-cac9-43cc-96f2-7695f909819d",
  "time": 222,
  "status": 200,
  "size": 24,
  "body": {
    "widgets": [],
    "links": []
  }
}

Usage

Include the module

requestFormatter = require('shiny-express-formatter');

Add middleware for formatting requests/responses

app.use(requestFormatter.formatRequests(options));

Ensure any request body parsing middleware (e.g. body-parser) is set prior to using the formatting middleware

Options

• onRequestCaptured: function(requestLogObject). callback to run once request object has been formatted. Useful for capturing request id to set bunyan child loggers. default: do nothing

• onResponseCaptured: function(requestLogObject, responseLogObject). callback to run once request and response objects have been formatted. default: do nothing

• captureRequestBody: boolean|function(req). whether to include the request body in the callback. default: false. If set to a function, returned results will be the boolean that determines whether to capture the body (allows logging only json bodies, for example)

• captureResponseBody: boolean|function(req, res). whether to include the response body in the callback. default: false. If set to a function, returned results will be the boolean that determines whether to capture the body (allows logging only json bodies, for example)

• logRequestHeaders: boolean|function(req). whether to include the request body in the callback. default: true. If set to a function, returned results will be used as headers to log (allows filtering out sensitive headers)

• logResponseHeaders: boolean|function(req, res). whether to include the response body in the callback. default: true. If set to a function, returned results will be used as headers to log (allows filtering out sensitive headers)

possible future work

• add options to create conditions for which types of request/response bodies are captured (e.g. json only)