# API extensions

The changes below were introduced to the LXD API after the 1.0 API was finalized.

They are all backward compatible and can be detected by client tools by
looking at the api\_extensions field in GET /1.0/.


## storage\_zfs\_remove\_snapshots
A storage.zfs\_remove\_snapshots daemon configuration key was introduced.

It's a boolean that defaults to false and that when set to true instructs LXD
to remove any needed snapshot when attempting to restore another.

This is needed as ZFS will only let you restore the latest snapshot.

## container\_host\_shutdown\_timeout
A boot.host\_shutdown\_timeout container configuration key was introduced.

It's an integer which indicates how long LXD should wait for the container
to stop before killing it.

Its value is only used on clean LXD daemon shutdown. It defaults to 30s.

## container\_syscall\_filtering
A number of new syscalls related container configuration keys were introduced.

 * security.syscalls.blacklist\_default
 * security.syscalls.blacklist\_compat
 * security.syscalls.blacklist
 * security.syscalls.whitelist

See configuration.md for how to use them.

## auth\_pki
This indicates support for PKI authentication mode.

In this mode, the client and server both must use certificates issued by the same PKI.

See lxd-ssl-authentication.md for details.

## container\_last\_used\_at
A last\_used\_at field was added to the /1.0/containers/\<name\> GET endpoint.

It is a timestamp of the last time the container was started.

If a container has been created but not started yet, last\_used\_at field
will be 1970-01-01T00:00:00Z

## etag
Add support for the ETag header on all relevant endpoints.

This adds the following HTTP header on answers to GET:
 - ETag (SHA-256 of user modifiable content)

And adds support for the following HTTP header on PUT requests:
 - If-Match (ETag value retrieved through previous GET)

This makes it possible to GET a LXD object, modify it and PUT it without
risking to hit a race condition where LXD or another client modified the
object in the meantime.

## patch
Add support for the HTTP PATCH method.

PATCH allows for partial update of an object in place of PUT.

## https\_allowed\_credentials
To use LXD API with all Web Browsers (via SPAs) you must send credentials
(certificate) with each XHR (in order for this to happen, you should set
["withCredentials=true"](https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest/withCredentials)
flag to each XHR Request).

Some browsers like Firefox and Safari can't accept server response without
`Access-Control-Allow-Credentials: true` header. To ensure that the server will
return a response with that header, set `core.https_allowed_credentials=true`.

## image\_compression\_algorithm
This adds support for a compression\_algorithm property when creating an image (POST to /1.0/images).

Setting this property overrides the server default value (images.compression\_algorithm).

## directory\_manipulation
This allows for creating and listing directories via the LXD API, and exports
the file type via the X-LXD-type header, which can be either "file" or
"directory" right now.

## container\_cpu\_time
This adds support for retrieving cpu time for a running container.

## storage\_zfs\_use\_refquota
Introduces a new server property "storage.zfs\_use\_refquota" which instructs LXD
to set the "refquota" property instead of "quota" when setting a size limit
on a container. LXD will also then use "usedbydataset" in place of "used"
when being queried about disk utilization.

This effectively controls whether disk usage by snapshots should be
considered as part of the container's disk space usage.

## storage\_lvm\_mount\_options
Adds a new "storage.lvm\_mount\_options" daemon configuration option
which defaults to "discard" and allows the user to set addition mount
options for the filesystem used by the LVM LV.

## network
Network management API for LXD.

This includes:
 * Addition of the "managed" property on /1.0/networks entries
 * All the network configuration options (see configuration.md for details)
 * POST /1.0/networks (see rest-api.md for details)
 * PUT /1.0/networks/<entry> (see rest-api.md for details)
 * PATCH /1.0/networks/<entry> (see rest-api.md for details)
 * DELETE /1.0/networks/<entry> (see rest-api.md for details)
 * ipv4.address property on "nic" type devices (when nictype is "bridged")
 * ipv6.address property on "nic" type devices (when nictype is "bridged")
 * security.mac\_filtering property on "nic" type devices (when nictype is "bridged")

## profile\_usedby
Adds a new used\_by field to profile entries listing the containers that are using it.

## container\_push
When a container is created in push mode, the client serves as a proxy between
the source and target server. This is useful in cases where the target server
is behind a NAT or firewall and cannot directly communicate with the source
server and operate in pull mode.

## container\_exec\_recording
Introduces a new boolean "record-output", parameter to
/1.0/containers/<name>/exec which when set to "true" and combined with
with "wait-for-websocket" set to false, will record stdout and stderr to
disk and make them available through the logs interface.

The URL to the recorded output is included in the operation metadata
once the command is done running.

That output will expire similarly to other log files, typically after 48 hours.
