From: Daan De Meyer Date: Sun, 12 Apr 2020 17:39:51 +0000 (+0200) Subject: man: review of import1(5) X-Git-Tag: v246-rc1~567^2~5 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=b441a1d4bc3102bf7571b53f9f27f5f1e36e7548;p=thirdparty%2Fsystemd.git man: review of import1(5) --- diff --git a/man/org.freedesktop.import1.xml b/man/org.freedesktop.import1.xml index 6a628f46717..71469a9c5ef 100644 --- a/man/org.freedesktop.import1.xml +++ b/man/org.freedesktop.import1.xml @@ -25,18 +25,18 @@ systemd-importd.service8 - is a system service which may be used to import, export and download additional system images, for - running them as local containers using tools such as - systemd-nspawn1 The - service is used as backend for machinectl pull-raw and machinectl - pull-tar and related commands. - This page describes the D-Bus interface. + is a system service which may be used to import, export and download additional system images. These + images can be used by tools such as + systemd-nspawn1 + to run local containers. The service is used as the backend for machinectl pull-raw, + machinectl pull-tar and related commands. This page describes the D-Bus interface. + Note that systemd-importd.service8 is mostly a small companion service for systemd-machined.service8. - Many operations to manipulate local container and VM images are hence available via the systemd-machined bus API, c.f. + Many operations to manipulate local container and VM images are hence available via the systemd-machined D-Bus API, c.f. org.freedesktop.machine1.service5. @@ -116,8 +116,8 @@ node /org/freedesktop/import1 { ImportTar() and ImportRaw() import a system image and place it into /var/lib/machines/. The first argument should be a file descriptor - (opened for reading) referring to the tar or raw file to import. It should reference either a file on - disk or a pipe or socket. When ImportTar() is used the file descriptor should + (opened for reading) referring to the tar or raw file to import. It should reference a file on disk, + a pipe or a socket. When ImportTar() is used the file descriptor should refer to a tar file, optionally compressed with gzip1, bzip21, @@ -126,58 +126,59 @@ node /org/freedesktop/import1 { systemd-importd will detect the used compression scheme (if any) automatically. When ImportRaw() is used the file descriptor should refer to a raw or qcow2 disk image containing an MBR or GPT disk label, also optionally compressed with gzip, bzip2 or xz. In either case, - if the file is specified as file descriptor on disk, progress information is generated for the import - operation (since the size on disk is known then), if a socket or pipe is specified this is not + if the file is specified as a file descriptor on disk, progress information is generated for the import + operation (as in that case we know the total size on disk). If a socket or pipe is specified, progress information is not available. The file descriptor argument is followed by a local name for the image. This should be a name suitable as a hostname and will be used to name the imported image below - /var/lib/machines. A tar import is placed as directory tree or + /var/lib/machines. A tar import is placed as a directory tree or a btrfs8 - subvolume below /var/lib/machines/, under the name specified with no suffix - appended. A raw import is placed as file in /var/lib/machines/ with the - .raw suffix appended. The argument controls whether any - pre-existing image with the same name shall be removed for the operation. If true, it is removed, if - false the operation fails on a name conflict. Finally, the argument controls - whether to create a writable or read-only image. The two calls return immediately after invocation, + subvolume below /var/lib/machines/ under the specified name with no suffix + appended. A raw import is placed as a file in /var/lib/machines/ with the + .raw suffix appended. If the argument is true, any + pre-existing image with the same name is removed before starting the operation. Otherwise, the + operation fails if an image with the same name already exists. Finally, the + argument controls + whether to create a writable or read-only image. Both methods return immediately after starting the import, with the import transfer ongoing. They return a pair of transfer identifier and object path, which may - be used to retrieve progress information about the transfer, or cancel it. The transfer identifier is a + be used to retrieve progress information about the transfer or to cancel it. The transfer identifier is a simple numeric identifier, the object path references an org.freedesktop.import1.Transfer object, see below. Listen for a - TransferRemoved signal for the transfer ID it order to detect when a transfer is + TransferRemoved signal for the transfer ID in order to detect when a transfer is complete. The returned transfer object is useful to determine the current progress or log output of the ongoing import operation. ExportTar() and ExportRaw() implement the reverse operation, and may be used to export a system image in order to place it in a tar or raw image. They - take the machine name to export as first parameter, followed by a file descriptor (opened for writing) + take the machine name to export as their first parameter, followed by a file descriptor (opened for writing) where the tar or raw file will be written. It may either reference a file on disk or a pipe/socket. The third argument specifies in which compression format to write the image. It takes one of uncompressed, xz, bzip2 or gzip, depending on which compression scheme is required. The image written to the specified file descriptor will be a tar file in case of ExportTar() or a raw disk image in case of ExportRaw(). Note that currently raw disk images may not be - exported as tar files, and vice versa, however this restriction might be lifted eventually. The call - returns a transfer identifier and object path for canceling or tracking the export operation, similar - to ImportTar() or ImportRaw() described above. + exported as tar files, and vice versa. This restriction might be lifted eventually. The call + returns a transfer identifier and object path for cancelling or tracking the export operation, similar + to ImportTar() or ImportRaw() as described above. PullTar() and PullRaw() may be used to download, verify - and import a system image from a web site. They take an URL argument, that should reference a tar or + and import a system image from a URL. They take an URL argument which should point to a tar or raw file on the http:// or https:// protocols, possibly compressed with xz, bzip2 or gzip. The second argument is a local name for the image. It should be - suitable as hostname, similar to the matching argument of the ImportTar() and - ImportRaw() calls above. The third argument indicates the verification mode for + suitable as a hostname, similar to the matching argument of the ImportTar() and + ImportRaw() methods above. The third argument indicates the verification mode for the image. It may be one of no, checksum, - signature. no turns of any kind of verification of the image; + signature. no turns off any kind of verification of the image; checksum looks for a SHA256SUM file next to the downloaded - image, and verifies any SHA256 hash value in that file again the image; signature + image and verifies any SHA256 hash value in that file against the image; signature does the same but also tries to authenticate the SHA256SUM file via gpg8 first. The last argument indicates whether to replace a possibly pre-existing image with the same local name (if true), or whether to fail (if false). Like the import - and export calls above these calls return a pair of transfer identifier and object path for the ongoing + and export calls above, these calls return a pair of transfer identifier and object path for the ongoing download. ListTransfers() returns a list of ongoing import, export or download - operations, as created with the six calls described above. It returns an array of structures, which + operations as created with the six calls described above. It returns an array of structures which consist of the numeric transfer identifier, a string indicating the operation (one of import-tar, import-raw, export-tar, export-raw, pull-tar or pull-raw), a string @@ -187,18 +188,18 @@ node /org/freedesktop/import1 { the transfer object path. CancelTransfer() may be used to cancel an ongoing import, export or download - operation. Simply specify the transfer identifier to cancel. + operation. Simply specify the transfer identifier to cancel the ongoing operation. Signals - The TransferNew signal is generated each time a new transfer is added with - the import, export or download calls described above. It carries the transfer ID and object path just - created. + The TransferNew signal is generated each time a new transfer is started with + the import, export or download calls described above. It carries the transfer ID and object path that + have just been created. - The TransferRemoved signal is sent each time a transfer was completed, - canceled or failed. It also carries the transfer ID and object path, followed by a string indicating + The TransferRemoved signal is sent each time a transfer finishes, + is canceled or fails. It also carries the transfer ID and object path, followed by a string indicating the result of the operation, which is one of done (on success), canceled or failed. @@ -255,17 +256,17 @@ node /org/freedesktop/import1/transfer/_1 { The Id property exposes the numeric transfer ID of the transfer object. - The Local, Remote, Type properties + The Local, Remote and Type properties expose the local container name of this transfer, the remote source (in case of download: the URL, in - case of import/export a string describing the file descriptor passed in), and the type of operation - (see the Manager's ListTransfer() call above for an explanation of the possible + case of import/export: a string describing the file descriptor passed in), and the type of operation + (see the Manager's ListTransfer() method above for an explanation of the possible values). - The Verify property exposes the selected verification setting, and is only + The Verify property exposes the selected verification setting and is only defined for download operations (see above). - The Progress property exposes the current progress of the transfer, as a value - between 0.0 and 1.0. To show a progress bar on screen it recommend to query this value in regular + The Progress property exposes the current progress of the transfer as a value + between 0.0 and 1.0. To show a progress bar on screen we recommend to query this value in regular intervals, for example every 500 ms or so.