Struct actix_web::middleware::Logger

pub struct Logger(_);

Middleware for logging request and response summaries to the terminal.

This middleware uses the log crate to output information. Enable log's output for the "actix_web" scope using env_logger or similar crate.

Default Format

The default Logger uses the following format:

%a "%r" %s %b "%{Referer}i" "%{User-Agent}i" %T

Example Output:
127.0.0.1:54278 "GET /test HTTP/1.1" 404 20 "-" "HTTPie/2.2.0" 0.001074

Usage

use actix_web::{middleware::Logger, App};

// access logs are printed with the INFO level so ensure it is enabled by default
env_logger::init_from_env(env_logger::Env::new().default_filter_or("info"));

let app = App::new()
    // .wrap(Logger::default())
    .wrap(Logger::new("%a %{User-Agent}i"));

Format

Variable	Description
%%	The percent sign
%a	Peer IP address (or IP address of reverse proxy if used)
%t	Time when the request started processing (in RFC 3339 format)
%r	First line of request (Example: GET /test HTTP/1.1)
%s	Response status code
%b	Size of response in bytes, including HTTP headers
%T	Time taken to serve the request, in seconds to 6 decimal places
%D	Time taken to serve the request, in milliseconds
%U	Request URL
%{r}a	"Real IP" remote address *
%{FOO}i	request.headers["FOO"]
%{FOO}o	response.headers["FOO"]
%{FOO}e	env_var["FOO"]
%{FOO}xi	Custom request replacement labelled "FOO"

Security

* "Real IP" remote address is calculated using ConnectionInfo::realip_remote_addr()

If you use this value, ensure that all requests come from trusted hosts. Otherwise, it is trivial for the remote client to falsify their source IP address.

Implementations

impl Logger

pub fn new(format: &str) -> Logger

Create Logger middleware with the specified format.

pub fn exclude<T: Into<String>>(self, path: T) -> Self

Ignore and do not log access info for specified path.

pub fn exclude_regex<T: Into<String>>(self, path: T) -> Self

Ignore and do not log access info for paths that match regex.

pub fn custom_request_replace(
    self,
    label: &str,
    f: impl Fn(&ServiceRequest) -> String + 'static
) -> Self

Register a function that receives a ServiceRequest and returns a String for use in the log line. The label passed as the first argument should match a replacement substring in the logger format like %{label}xi.

It is convention to print "-" to indicate no output instead of an empty string.

Example

Logger::new("example %{JWT_ID}xi")
    .custom_request_replace("JWT_ID", |req| parse_jwt_id(req.headers().get("Authorization")));

Trait Implementations

impl Debug for Logger

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Logger

pub fn default() -> Logger

Create Logger middleware with format:

%a "%r" %s %b "%{Referer}i" "%{User-Agent}i" %T

impl<S, B> Transform<S, ServiceRequest> for Logger where
    S: Service<ServiceRequest, Response = ServiceResponse<B>, Error = Error>,
    B: MessageBody, 

type Response = ServiceResponse<StreamLog<B>>

Responses given by the service.

type Error = Error

Errors produced by the service.

type InitError = ()

Errors produced while building a transform service.

type Transform = LoggerMiddleware<S>

The TransformService value created by this factory

type Future = Ready<Result<Self::Transform, Self::InitError>>

The future response value.

pub fn new_transform(&self, service: S) -> Self::Future

Creates and returns a new Transform component, asynchronously

pub fn map_init_err<F, E>(self, f: F) -> TransformMapInitErr<Self, S, Req, F, E> where
    F: Fn(Self::InitError) -> E + Clone, 

Map this transform's factory error to a different error, returning a new transform service factory.