README.md

Audit.HttpClient

HttpClient audit extension for Audit.NET library.

Generate Audit Logs by intercepting HttpClient REST calls. Audit.HttpClient provides the infrastructure to create audit logs for an instance of HttpClient class.

It relies on a message handler to incercept the calls to HttpClient methods.

Install

NuGet Package

To install the package run the following command on the Package Manager Console:

PM> Install-Package Audit.HttpClient

Usage

To enable the audit log for HttpClient, you have to set an AuditHttpClientHandler as a message handler for the HttpClient instance being audited.

This can be done in different ways:

• Call the factory provided by Audit.Http.ClientFactory.Create() method to get a new audit-enabled instance of HttpClient:

var httpClient = Audit.Http.ClientFactory.Create(_ => _
    .IncludeRequestBody()
    .IncludeResponseHeaders()
    .FilterByRequest(req => req.Method.Method == "GET"));

The ClientFactory.Create method is just a shortcut to create a new HttpClient with a custom AuditHttpClientHandler as its message handler.

• If you use ASP .NET dependency injection / HttpClientFactory, you can add the message handler with the extension method AddAuditHandler() on your startup:

using Audit.Http;

public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddHttpClient("GitHub", c =>
        {
            c.BaseAddress = new Uri("https://api.github.com/");
        })
        .AddAuditHandler(audit => audit
            .IncludeRequestBody()
            .IncludeResponseHeaders());
    }
}

Note: AddAuditHandler(config) is a shortcut for AddHttpMessageHandler(() => new AuditHttpClientHandler(config))

• You can also create an audited HttpClient passing the handler to its constructor:

var httpClient = new HttpClient(new AuditHttpClientHandler(_ => _
    .IncludeRequestBody()
    .IncludeResponseHeaders());

Each method call on the audited HttpClient instances will generate an Audit Event.

Configuration

Output

The audit events are stored using a Data Provider. You can use one of the available data providers or implement your own. Please refer to the data providers section on Audit.NET documentation.

Settings

The AuditHttpClientHandler class allows to configure the following settings:

• RequestFilter / FilterByRequest: Set a filter function to determine which events to log depending on the request message. By default all events are logged.
• ResponseFilter / FilterByResponse: Set a filter function to determine which events to log depending on the response message. By default all events are logged.
• EventType: A string that identifies the event type. Default is "{verb} {url}". It can contain the following placeholders:
  • {verb}: Replaced by the Http Verb (GET, POST, ...)
  • {url}: Replaced by the request URL
• IncludeRequestHeaders: Specifies whether the HTTP Request headers should be included on the audit output. Default is false.
• IncludeResponseHeaders: Specifies whether the HTTP Response headers should be included on the audit output. Default is false.
• IncludeContentHeaders: Specifies whether the HTTP Content headers should be included on the audit output. Default is false.
• IncludeRequestBody: Specifies whether the HTTP Request body should be included on the audit output. Default is false.
• IncludeResponseBody: Specifies whether the HTTP Response body should be included on the audit output. Default is false.
• IncludeOptions: Specifies which HTTP Request Options should be included in the audit output. Useful to add contextual information to the HTTP Audit Event. By default, the options are not included.
• CreationPolicy: Allows to set a specific event creation policy. By default the globally configured creation policy is used. See Audit.NET Event Creation Policy section for more information.
• AuditDataProvider: Allows to set a specific audit data provider. By default the globally configured data provider is used. See Audit.NET Data Providers section for more information.
• AuditScopeFactory: Allows to set a specific audit scope factory. By default the globally configured AuditScopeFactory is used.

Output Details

The following table describes the Audit.HttpClient output fields:

HttpAction

Describes an operation call event

Field Name	Type	Description
Method	string	HTTP rest method
Url	string	Request URL
Version	string	Http client version
Exception	string	Exception details when an exception is thrown
Request	Request	Request audit information
Response	Response	Response audit information

Request

Describes a HTTP request

Field Name	Type	Description
QueryString	string	Query string portion of the request URL
Scheme	string	Request scheme (http, https)
Path	string	Path portion of the request URL
Headers	Dictionary	Request headers
Content	Content	Request content

Response

Describes a HTTP response

Field Name	Type	Description
StatusCode	int	Response HTTP status code
Status	string	String representation of the response status code
Reason	string	Response status reason phrase
IsSuccess	bool	Indicates if the HTTP response was successful.
Headers	Dictionary	Request headers
Content	Content	Request content

Content

Describes the content of a HTTP request or response

Field Name	Type	Description
Body	string	Response body content decoded as a string
Headers	Dictionary	Content headers

Output Sample

{
	"EventType": "GET http://google.com/doesnotexists",
	"Environment": {
		"UserName": "Federico",
		"MachineName": "FEDE",
		"DomainName": "FEDE",
		"Culture": "en-US"
	},
	"StartDate": "2019-05-21T23:18:38.3251378Z",
	"EndDate": "2019-05-21T23:18:40.4623427Z",
	"Duration": 2137,
	"Action": {
		"Method": "GET",
		"Url": "http://google.com/doesnotexists",
		"Version": "1.1",
		"Request": {
			"QueryString": "",
			"Scheme": "http",
			"Path": "/doesnotexists",
			"Headers": {
				
			}
		},
		"Response": {
			"Headers": {
				"Date": "Tue, 21 May 2019 23:18:19 GMT",
				"Referrer-Policy": "no-referrer"
			},
			"Content": {
				"Body": "<!DOCTYPE html>\n<html lang=en>\n  <meta charset=utf-8>\n ....",
				"Headers": {
					"Content-Length": "1574",
					"Content-Type": "text/html; charset=UTF-8"
				}
			},
			"StatusCode": 404,
			"Status": "NotFound",
			"Reason": "Not Found",
			"IsSuccess": false
		}
	}
}