Bug#1095450: `fwupdmgr --json update` outputs invalid JSON

[Lee Garrett <debian@rocketjump.eu>]

Package: fwupd
Version: 2.0.5-1
Severity: minor
X-Debbugs-Cc: debian@rocketjump.eu

Hi,

at least one command outputs invalid JSON despite the --json flag:

randall@batou:~$ fwupdmgr --json get-devices | jsonlint
<stdin>: ok
randall@batou:~$ fwupdmgr --json update | jsonlint
<stdin>:1:0: Error: Unknown identifier: 'Devices'
   |  At line 1, column 0, offset 0 (AT-START)
<stdin>:1:8: Error: Unexpected text after end of JSON value
   |  At line 1, column 8, offset 8
<stdin>: has errors
randall@batou:~$ fwupdmgr --json update
Devices with no available firmware updates:
 • USB3.1 Hub
 • USB3.1 Hub
 • MZVLB1T0HBLR-000L7
 • Prometheus
 • Prometheus IOTA Config
 • System Firmware
 • ThinkPad USB-C Dock Gen2
 • ThinkPad USB-C Dock Gen2 PD Controller
 • ThinkPad USB-C Dock Gen2 USB Audio
 • Thunderbolt host controller
 • UEFI Device Firmware
 • UEFI Device Firmware
 • UEFI Device Firmware
 • UEFI Device Firmware
 • UEFI Device Firmware
 • USB2.0 Hub
 • USB2.0 Hub
{
  "Error" : {
    "Domain" : "FwupdError",
    "Code" : 9,
    "Message" : "No updatable devices"
  }
}

would be nice if the "update" command would output valid JSON, and maybe we
could add some autopkgtest to test it?

Greets,
Lee

-- System Information:
Debian Release: trixie/sid
  APT prefers testing
  APT policy: (990, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 6.12.11-amd64 (SMP w/8 CPU threads; PREEMPT)
Kernel taint flags: TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages fwupd depends on:
ii  libarchive13t64             3.7.4-1.1
ii  libblkid1                   2.40.4-2
ii  libc6                       2.40-6
ii  libcbor0.10                 0.10.2-2
ii  libcurl3t64-gnutls          8.11.1-1+b1
ii  libdrm-amdgpu1              2.4.123-1
ii  libdrm2                     2.4.123-1
ii  libflashrom1                1.4.0-3
ii  libfwupd3                   2.0.5-1
ii  libglib2.0-0t64             2.82.4-2
ii  libgnutls30t64              3.8.8-2
ii  libjcat1                    0.2.0-2+b3
ii  libjson-glib-1.0-0          1.10.6+ds-1
ii  liblzma5                    5.6.3-1+b1
ii  libmbim-glib4               1.30.0-1+b2
ii  libmbim-proxy               1.30.0-1+b2
ii  libmm-glib0                 1.22.0-3+b2
ii  libpolkit-gobject-1-0       126-2
ii  libprotobuf-c1              1.5.1-1
ii  libqmi-glib5                1.34.0-2+b2
ii  libqmi-proxy                1.34.0-2+b2
ii  libsqlite3-0                3.46.1-1
ii  libsystemd0                 257.2-3
ii  libtss2-esys-3.0.2-0t64     4.1.3-1.2
ii  libusb-1.0-0                2:1.0.27-2
ii  libxmlb2                    0.3.21-1
ii  shared-mime-info            2.4-5+b2
ii  systemd [systemd-sysusers]  257.2-3
ii  zlib1g                      1:1.3.dfsg+really1.3.1-1+b1

Versions of packages fwupd recommends:
ii  bolt                               0.9.8-1
ii  dbus [default-dbus-system-bus]     1.16.0-1
ii  fwupd-amd64-signed [fwupd-signed]  1:1.7+1
ii  jq                                 1.7.1-3+b1
ii  python3                            3.13.1-2
pn  secureboot-db                      <none>
ii  udisks2                            2.10.1-11

Versions of packages fwupd suggests:
pn  gir1.2-fwupd-2.0  <none>

-- Configuration Files:
/etc/fwupd/fwupd.conf [Errno 13] Permission denied: '/etc/fwupd/fwupd.conf'

-- no debconf information