apt-transport-http

APT-TRANSPORT-HTTP(1)                 APT                APT-TRANSPORT-HTTP(1)

NAME
       apt-transport-http - APT transport for downloading via the Hypertext
       Transfer Protocol (HTTP)

DESCRIPTION
       This APT transport allows the use of repositories accessed via the
       Hypertext Transfer Protocol (HTTP). It is available by default and
       probably the most used of all transports. Note that a transport is
       never called directly by a user but used by APT tools based on user
       configuration.

       HTTP is an unencrypted transport protocol meaning that the whole
       communication with the remote server (or proxy) can be observed by a
       sufficiently capable attacker commonly referred to as a "man in the
       middle" (MITM). However, such an attacker can not modify the
       communication to compromise the security of your system, as APT's data
       security model is independent of the chosen transport method. This is
       explained in detail in apt-secure(8). An overview of available
       transport methods is given in sources.list(5).

OPTIONS
       Various options can be set in an apt.conf(5) file to modify its
       behavior, ranging from proxy configuration to workarounds for specific
       server limitations.

   Proxy Configuration
       The environment variable http_proxy is supported for system wide
       configuration. Proxies specific to APT can be configured via the option
       Acquire::http::Proxy. Proxies which should be used only for certain
       hosts can be specified via Acquire::http::Proxy::host. Even more
       fine-grained control can be achieved via proxy autodetection, detailed
       further below. All these options use the URI format
       scheme://[[user][:pass]@]host[:port]/. Supported URI schemes are
       socks5h (SOCKS5 with remote DNS resolution), http and https.
       Authentication details can be supplied via apt_auth.conf(5) instead of
       including it in the URI directly.

       The various APT configuration options support the special value DIRECT
       meaning that no proxy should be used. The environment variable no_proxy
       is also supported for the same purpose.

       Furthermore, there are three settings provided for cache control with
       HTTP/1.1 compliant proxy caches: Acquire::http::No-Cache tells the
       proxy not to use its cached response under any circumstances.
       Acquire::http::Max-Age sets the allowed maximum age (in seconds) of an
       index file in the cache of the proxy.  Acquire::http::No-Store
       specifies that the proxy should not store the requested archive files
       in its cache, which can be used to prevent the proxy from polluting its
       cache with (big) .deb files.

   Automatic Proxy Configuration
       Acquire::http::Proxy-Auto-Detect can be used to specify an external
       command to discover the HTTP proxy to use. The first and only parameter
       is a URI denoting the host to be contacted, to allow for host-specific
       configuration. APT expects the command to output the proxy on stdout as
       a single line in the previously specified URI format or the word DIRECT
       if no proxy should be used. No output indicates that the generic proxy
       settings should be used.

       Note that auto-detection will not be used for a host if a host-specific
       proxy configuration is already set via Acquire::http::Proxy::host.

       See the squid-deb-proxy-client(1) and auto-apt-proxy(1) packages for
       example implementations.

       This option takes precedence over the legacy option name
       Acquire::http::ProxyAutoDetect.

   Connection Configuration
       The option Acquire::http::Timeout sets the timeout timer used by the
       method; this value applies to the connection as well as the data
       timeout.

       The used bandwidth can be limited with Acquire::http::Dl-Limit which
       accepts integer values in kilobytes per second. The default value is 0
       which deactivates the limit and tries to use all available bandwidth.
       Note that this option implicitly disables downloading from multiple
       servers at the same time.

       The setting Acquire::http::Pipeline-Depth can be used to enable HTTP
       pipelining (RFC 2616 section 8.1.2.2) which can be beneficial e.g. on
       high-latency connections. It specifies how many requests are sent in a
       pipeline. APT tries to detect and work around misbehaving webservers
       and proxies at runtime, but if you know that yours does not conform to
       the HTTP/1.1 specification, pipelining can be disabled by setting the
       value to 0. It is enabled by default with the value 10.

       Acquire::http::AllowRedirect controls whether APT will follow
       redirects, which is enabled by default.

       Acquire::http::User-Agent can be used to set a different User-Agent for
       the http download method as some proxies allow access for clients only
       if the client uses a known identifier.

       Acquire::http::SendAccept is enabled by default and sends an Accept:
       text/* header field to the server for requests without file extensions
       to prevent the server from attempting content negotiation.

EXAMPLES
           Acquire::http {
                Proxy::example.org "DIRECT";
                Proxy "socks5h://apt:pass@127.0.0.1:9050";
                Proxy-Auto-Detect "/usr/local/bin/apt-http-proxy-auto-detect";
                No-Cache "true";
                Max-Age "3600";
                No-Store "true";
                Timeout "10";
                Dl-Limit "42";
                Pipeline-Depth "0";
                AllowRedirect "false";
                User-Agent "My APT-HTTP";
                SendAccept "false";
           };

SEE ALSO
       apt.conf(5) apt_auth.conf(5) sources.list(5)

BUGS
       APT bug page[1]. If you wish to report a bug in APT, please see
       /usr/share/doc/debian/bug-reporting.txt or the reportbug(1) command.

AUTHOR
       APT team

NOTES
        1. APT bug page
           http://bugs.debian.org/src:apt

APT 2.0.10                       04 April 2019           APT-TRANSPORT-HTTP(1)