mongoose/UserManual.md

# Overview

Mongoose is small and easy to use web server. It is self-contained, and does
not require any external software to run.

On Windows, mongoose iconifies itself to the system tray icon when started.
Right-click on the icon pops up a menu, where it is possible to stop
mongoose, or configure it, or install it as Windows service. The easiest way
to share a folder on Windows is to copy `mongoose.exe` to a folder,
double-click the exe, and launch a browser at
[http://localhost:8080](http://localhost:8080). Note that 'localhost' should
be changed to a machine's name if a folder is accessed from other computer.

On UNIX and Mac, mongoose is a command line utility. Running `mongoose` in
terminal, optionally followed by configuration parameters
(`mongoose [OPTIONS]`) or configuration file name
(`mongoose [config_file_name]`) starts the
web server. Mongoose does not detach from terminal. Pressing `Ctrl-C` keys
would stop the server.

When started, mongoose first searches for the configuration file.
If configuration file is specified explicitly in the command line, i.e.
`mongoose path_to_config_file`, then specified configuration file is used.
Otherwise, mongoose would search for file `mongoose.conf` in the same directory
where binary is located, and use it. Configuration file can be absent.


Configuration file is a sequence of lines, each line containing
command line argument name and it's value. Empty lines, and lines beginning
with `#`, are ignored. Here is the example of `mongoose.conf` file:

    document_root c:\www
    listening_ports 8080,8043s
    ssl_certificate c:\mongoose\ssl_cert.pem

When configuration file is processed, mongoose process command line arguments,
if they are specified. Command line arguments therefore can override
configuration file settings. Command line arguments must start with `-`.
For example, if `mongoose.conf` has line
`document_root /var/www`, and mongoose has been started as
`mongoose -document_root /etc`, then `/etc` directory will be served as
document root, because command line options take priority over
configuration file. Configuration options section below provide a good
overview of Mongoose features.

Mongoose can also be used to modify `.htpasswd` passwords file:

    mongoose -A <htpasswd_file> <realm> <user> <passwd>

Unlike other web servers, mongoose does not require CGI scripts be located in
a special directory. CGI scripts can be anywhere. CGI (and SSI) files are
recognized by the file name pattern. Mongoose uses shell-like glob
patterns. Pattern match starts at the beginning of the string, so essentially
patterns are prefix patterns. Syntax is as follows:

     **      Matches everything
     *       Matches everything but slash character, '/'
     ?       Matches any character
     $       Matches the end of the string
     |       Matches if pattern on the left side or the right side matches.

All other characters in the pattern match themselves. Examples:

    **.cgi$      Any string that ends with .cgi
    /foo         Any string that begins with /foo
    **a$|**b$    Any string that ends with a or b

# Configuration Options

Below is a list of configuration options Mongoose understands. Every option
is followed by it's default value. If default value is not present, then
it is empty.

### cgi_pattern `**.cgi$|**.pl$|**.php$`
All files that match `cgi_pattern` are treated as CGI files. Default pattern
allows CGI files be anywhere. To restrict CGIs to a certain directory,
use `/path/to/cgi-bin/**.cgi` as pattern. Note that full file path is
matched against the pattern, not the URI.

### cgi_environment
Extra environment variables to be passed to the CGI script in
addition to standard ones. The list must be comma-separated list
of name=value pairs, like this: `VARIABLE1=VALUE1,VARIABLE2=VALUE2`.

### put\_delete\_passwords_file
Passwords file for PUT and DELETE requests. Without it, PUT and DELETE requests
will fail.

### cgi_interpreter
Path to an executable to use as CGI interpreter for __all__ CGI scripts
regardless script extension. If this option is not set (which is a default),
Mongoose looks at first line of a CGI script,
[shebang line](http://en.wikipedia.org/wiki/Shebang_(Unix)), for an interpreter.

For example, if both PHP and perl CGIs are used, then
`#!/path/to/php-cgi.exe` and `#!/path/to/perl.exe` must be first lines of the
respective CGI scripts. Note that paths should be either full file paths,
or file paths relative to the current working directory of mongoose server.
If mongoose is started by mouse double-click on Windows, current working
directory is a directory where mongoose executable is located.

If all CGIs use the same interpreter, for example they are all PHP, then
`cgi_interpreter` can be set to the path to `php-cgi.exe` executable and
shebang line in the CGI scripts can be omitted.
Note that PHP scripts must use `php-cgi.exe` executable, not `php.exe`.

### protect_uri
Comma separated list of URI=PATH pairs, specifying that given
URIs must be protected with respected password files. Paths must be full
file paths.

### authentication_domain `mydomain.com`
Authorization realm used in `.htpasswd` authorization.

### ssi_pattern `**.shtml$|**.shtm$`
All files that match `ssi_pattern` are treated as SSI.
Unknown SSI directives are silently ignored. Currently, two SSI
directives are supported, `<!--#include ...>` and
`<!--#exec command>`. Note that `<!--#include ...>` directive supports
three path specifications:

    <!--#include virtual="path">  Path is relative to web server root
    <!--#include file="path">     Path is relative to web server working dir
    <!--#include "path">          Path is relative to current document

### throttle
Limit download speed for clients.  `throttle` is a comma-separated
list of key=value pairs, where key could be:

    *                   limit speed for all connections
    x.x.x.x/mask        limit speed for specified subnet
    uri_prefix_pattern  limit speed for given URIs

The value is a floating-point number of bytes per second, optionally
followed by a `k` or `m` character, meaning kilobytes and
megabytes respectively. A limit of 0 means unlimited rate. The
last matching rule wins. Examples:

    *=1k,10.0.0.0/8=0   limit all accesses to 1 kilobyte per second,
                        but give connections from 10.0.0.0/8 subnet
                        unlimited speed

    /downloads/=5k      limit accesses to all URIs in `/downloads/` to
                        5 kilobytes per secods. All other accesses are unlimited

### access\_log\_file
Path to a file for access logs. Either full path, or relative to current
working directory. If absent (default), then accesses are not logged.

### error\_log\_file
Path to a file for error logs. Either full path, or relative to current
working directory. If absent (default), then errors are not logged.

### enable\_directory\_listing `yes`
Enable directory listing, either `yes` or `no`.

### global\_passwords\_file
Path to a global passwords file, either full path or relative to the current
working directory. If set, per-directory `.htpasswd` files are ignored,
and all requests are authorised against that file.

### index_files `index.html,index.htm,index.cgi,index.shtml,index.php`
Comma-separated list of files to be treated as directory index
files.

### access\_control\_list
Access Control List (ACL) is a comma separated list
of IP subnets, each subnet is prepended by `-` or `+` sign. Plus
means allow, minus means deny. If subnet mask is omitted, like
`-1.2.3.4`, then it means a single IP address. Mask may vary from 0
to 32 inclusive. On each request, full list is traversed, and
last match wins. Default setting is to allow all accesses. Examples:

    -0.0.0.0/0,+192.168/16    deny all acccesses, only allow 192.168/16 subnet

### extra\_mime\_types
Extra mime types to recognize, in form `extension1=type1,exten-
sion2=type2,...`. Extension must include dot.  Example:
`.cpp=plain/text,.java=plain/text`

### listening_ports `8080`
Comma-separated list of ports to listen on. If the port is SSL, a
letter `s` must be appeneded, for example, `80,443s` will open
port 80 and port 443, and connections on port 443 will be SSL-ed.
For non-SSL ports, it is allowed to append letter `r`, meaning 'redirect'.
Redirect ports will redirect all their traffic to the first configured
SSL port. For example, if `listening_ports` is `80r,443s`, then all
HTTP traffic coming at port 80 will be redirected to HTTPS port 443.

It is possible to specify an IP address to bind to. In this case,
an IP address and a colon must be prepended to the port number.
For example, to bind to a loopback interface on port 80 and to
all interfaces on HTTPS port 443, use `127.0.0.1:80,443s`.

### document_root `.`
A directory to serve. By default, currect directory is served. Current
directory is commonly referenced as dot (`.`).

### ssl_certificate
Path to SSL certificate file. This option is only required when at least one
of the `listening_ports` is SSL.

### num_threads `50`
Number of worker threads. Mongoose handles each incoming connection in a
separate thread. Therefore, the value of this option is effectively a number
of concurrent HTTP connections Mongoose can handle.

### run\_as\_user
Switch to given user credentials after startup. Usually, this option is
required when mongoose needs to bind on privileged port on UNIX. To do
that, mongoose needs to be started as root. But running as root is a bad idea,
therefore this option can be used to drop privileges. Example:

    mongoose -listening_ports 80 -run_as_user nobody

### url\_rewrite\_patterns
Comma-separated list of URL rewrites in the form of
`uri_pattern=file_or_directory_path`. When Mongoose receives the request,
it constructs the file name to show by combining `document_root` and the URI.
However, if the rewrite option is used and `uri_pattern` matches the
requested URI, then `document_root` is ignored. Insted,
`file_or_directory_path` is used, which should be a full path name or
a path relative to the web server's current working directory. Note that
`uri_pattern`, as all mongoose patterns, is a prefix pattern.

This makes it possible to serve many directories outside from `document_root`,
redirect all requests to scripts, and do other tricky things. For example,
to redirect all accesses to `.doc` files to a special script, do:

    mongoose -url_rewrite_patterns **.doc$=/path/to/cgi-bin/handle_doc.cgi

Or, to imitate user home directories support, do:

    mongoose -url_rewrite_patterns /~joe/=/home/joe/,/~bill=/home/bill/

### hide\_files\_patterns
A pattern for the files to hide. Files that match the pattern will not
show up in directory listing and return `404 Not Found` if requested. Pattern
must be for a file name only, not including directory name.

# Common Problems
- PHP doesn't work - getting empty page, or 'File not found' error. The
  reason for that is wrong paths to the interpreter. Remember that with PHP,
  correct interpreter is `php-cgi.exe` (`php-cgi` on UNIX). Solution: specify
  full path to the PHP interpreter, e.g.:
    `mongoose -cgi_interpreter /full/path/to/php-cgi`

# Embedding
Embedding Mongoose is easy. Somewhere in the application code, `mg_start()`
function must be called. That starts the web server in a separate thread.
When it is not needed anymore, `mg_stop()` must be called.  Application code
can pass configuration options to `mg_start()`, and also specify callback
functions that Mongoose should call at certain events.
[hello.c](https://github.com/valenok/mongoose/blob/master/examples/hello.c)
provides a minimalistic example.

Common pattern is to implement `begin_request` callback, and serve static files
from memory, and/or construct dynamic replies on the fly. Here is
my [embed.c](https://gist.github.com/valenok/4714740) gist
that shows how to easily any data can be embedded
directly into the executable. If such data needs to be encrypted, then
encrypted database or encryption dongles would be a better choice.


# Other Resources
- Presentation made by Arnout Vandecappelle at FOSDEM 2011 on 2011-02-06
  in Brussels, Belgium, called
  "Creating secure web based user interfaces for Embedded Devices"
  ([pdf](http://mind.be/content/110206_Web-ui.pdf) |
   [odp](http://mind.be/content/110206_Web-ui.odp))
- Linux Journal article by Michel J.Hammel, 2010-04-01, called
  [Mongoose: an Embeddable Web Server in C](http://www.linuxjournal.com/article/10680)