diff mbox series

[v5,1/4] avocado_qemu: Fix KNOWN_DISTROS map into the LinuxDistro class

Message ID 20210706131729.30749-2-eric.auger@redhat.com (mailing list archive)
State New, archived
Headers show
Series avocado-qemu: New SMMUv3 and intel IOMMU tests | expand

Commit Message

Eric Auger July 6, 2021, 1:17 p.m. UTC
From: Willian Rampazzo <willianr@redhat.com>

As the KNOWN_DISTROS grows, more loosely methods will be created in
the avocado_qemu/__init__.py file.

Let's refactor the code so that KNOWN_DISTROS and related methods are
packaged in a class

Signed-off-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 tests/acceptance/avocado_qemu/__init__.py | 74 +++++++++++++----------
 1 file changed, 42 insertions(+), 32 deletions(-)

Comments

Cleber Rosa July 8, 2021, 1:17 a.m. UTC | #1
On 7/6/21 9:17 AM, Eric Auger wrote:
> From: Willian Rampazzo <willianr@redhat.com>
>
> As the KNOWN_DISTROS grows, more loosely methods will be created in
> the avocado_qemu/__init__.py file.
>
> Let's refactor the code so that KNOWN_DISTROS and related methods are
> packaged in a class
>
> Signed-off-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
> Signed-off-by: Eric Auger <eric.auger@redhat.com>
> ---
>   tests/acceptance/avocado_qemu/__init__.py | 74 +++++++++++++----------
>   1 file changed, 42 insertions(+), 32 deletions(-)
>
> diff --git a/tests/acceptance/avocado_qemu/__init__.py b/tests/acceptance/avocado_qemu/__init__.py
> index 81ac90bebb..af93cd63ea 100644
> --- a/tests/acceptance/avocado_qemu/__init__.py
> +++ b/tests/acceptance/avocado_qemu/__init__.py
> @@ -299,29 +299,43 @@ def ssh_command(self, command):
>                            f'Guest command failed: {command}')
>           return stdout_lines, stderr_lines
>   
> +class LinuxDistro:
> +    """Represents a Linux distribution
>   


I definitely like the idea.


> -#: A collection of known distros and their respective image checksum
> -KNOWN_DISTROS = {
> -    'fedora': {
> -        '31': {
> -            'x86_64':
> -            {'checksum': 'e3c1b309d9203604922d6e255c2c5d098a309c2d46215d8fc026954f3c5c27a0'},
> -            'aarch64':
> -            {'checksum': '1e18d9c0cf734940c4b5d5ec592facaed2af0ad0329383d5639c997fdf16fe49'},
> -            'ppc64':
> -            {'checksum': '7c3528b85a3df4b2306e892199a9e1e43f991c506f2cc390dc4efa2026ad2f58'},
> -            's390x':
> -            {'checksum': '4caaab5a434fd4d1079149a072fdc7891e354f834d355069ca982fdcaf5a122d'},
> +    Holds information of known distros.
> +    """
> +    #: A collection of known distros and their respective image checksum
> +    KNOWN_DISTROS = {
> +        'fedora': {
> +            '31': {
> +                'x86_64':
> +                {'checksum': 'e3c1b309d9203604922d6e255c2c5d098a309c2d46215d8fc026954f3c5c27a0'},
> +                'ppc64':
> +                {'checksum': '7c3528b85a3df4b2306e892199a9e1e43f991c506f2cc390dc4efa2026ad2f58'},
> +                's390x':
> +                {'checksum': '4caaab5a434fd4d1079149a072fdc7891e354f834d355069ca982fdcaf5a122d'},
>               }
>           }
>       }
>   
> +    def __init__(self, name, version, arch):
> +        self.name = name
> +        self.version = version
> +        self.arch = arch


This looks a lot like 
https://github.com/avocado-framework/avocado/blob/f0996dafefa412c77c221c2d1a6fafdcba1c97b7/avocado/utils/distro.py#L34 
, although admittedly, their goals are very different.


As a next step, in the future, I'd consider separating the data from the 
actual class and having it the LinuxDistro instances, helped by a 
registry.  Something like:


class LinuxDistroRegistry:

    def __init__(self):
       self.distros = set()

    def register(self, linux_distro):

       self.distros.add(linux_distro)

    def query(self, **kwargs):

       ...


registry = LinuxDistroRegistry()

registry.register(LinuxDistro('fedora', '31', 'x86_64', 'deadbeefdeadbeef'))

registry.register(LinuxDistro('fedora', '31', 'aarch64', 
'beefdeadbeefdead'))

checksum = registry.query(name='fedora', version='31', 
arch='x86_64').checksum


> +        try:
> +            self._info = self.KNOWN_DISTROS.get(name).get(version).get(arch)


The `AttributeError` that could be caught at the removed 
`get_known_distro_checksum()` function, could come from any of the 
`.get()`s returning `None`, which in turn would not have a `.get()` 
attribute.

But now, if there's a "name", then a "version", but no "arch" entry, 
this line will set `self._info` to `None`.  This is manifested if you 
try to run a test that tries to find an aarch64 distro, such as:

./tests/venv/bin/avocado run 
tests/acceptance/boot_linux.py:BootLinuxAarch64.test_virt_tcg_gicv2


It will result in:


20:38:18 ERROR| Reproduced traceback from: 
/var/lib/users/cleber/build/qemu/tests/venv/lib64/python3.9/site-packages/avocado/core/test.py:756
20:38:18 ERROR| Traceback (most recent call last):
20:38:18 ERROR|   File 
"/var/lib/users/cleber/build/qemu/tests/acceptance/avocado_qemu/__init__.py", 
line 426, in download_boot
20:38:18 ERROR|     checksum=self.distro.checksum,
20:38:18 ERROR|   File 
"/var/lib/users/cleber/build/qemu/tests/acceptance/avocado_qemu/__init__.py", 
line 334, in checksum
20:38:18 ERROR|     return self._info.get('checksum', None)
20:38:18 ERROR| AttributeError: 'NoneType' object has no attribute 'get'
20:38:18 ERROR|
20:38:18 ERROR| During handling of the above exception, another 
exception occurred:
20:38:18 ERROR|
20:38:18 ERROR| Traceback (most recent call last):
20:38:18 ERROR|   File 
"/var/lib/users/cleber/build/qemu/tests/acceptance/avocado_qemu/__init__.py", 
line 387, in setUp
20:38:18 ERROR|     self.set_up_boot()
20:38:18 ERROR|   File 
"/var/lib/users/cleber/build/qemu/tests/acceptance/avocado_qemu/__init__.py", 
line 455, in set_up_boot
20:38:18 ERROR|     path = self.download_boot()
20:38:18 ERROR|   File 
"/var/lib/users/cleber/build/qemu/tests/acceptance/avocado_qemu/__init__.py", 
line 431, in download_boot
20:38:18 ERROR|     self.cancel('Failed to download/prepare boot image')
20:38:18 ERROR|   File 
"/var/lib/users/cleber/build/qemu/tests/venv/lib64/python3.9/site-packages/avocado/core/test.py", 
line 988, in cancel
20:38:18 ERROR|     raise exceptions.TestCancel(message)
20:38:18 ERROR| avocado.core.exceptions.TestCancel: Failed to 
download/prepare boot image


Cheers,

- Cleber.
Eric Auger July 8, 2021, 8:56 a.m. UTC | #2
Hi Wainer, William, Cleber,

On 7/8/21 3:17 AM, Cleber Rosa wrote:
>
> On 7/6/21 9:17 AM, Eric Auger wrote:
>> From: Willian Rampazzo <willianr@redhat.com>
>>
>> As the KNOWN_DISTROS grows, more loosely methods will be created in
>> the avocado_qemu/__init__.py file.
>>
>> Let's refactor the code so that KNOWN_DISTROS and related methods are
>> packaged in a class
>>
>> Signed-off-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
>> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>> ---
>>   tests/acceptance/avocado_qemu/__init__.py | 74 +++++++++++++----------
>>   1 file changed, 42 insertions(+), 32 deletions(-)
>>
>> diff --git a/tests/acceptance/avocado_qemu/__init__.py
>> b/tests/acceptance/avocado_qemu/__init__.py
>> index 81ac90bebb..af93cd63ea 100644
>> --- a/tests/acceptance/avocado_qemu/__init__.py
>> +++ b/tests/acceptance/avocado_qemu/__init__.py
>> @@ -299,29 +299,43 @@ def ssh_command(self, command):
>>                            f'Guest command failed: {command}')
>>           return stdout_lines, stderr_lines
>>   +class LinuxDistro:
>> +    """Represents a Linux distribution
>>   
>
>
> I definitely like the idea.
>
>
>> -#: A collection of known distros and their respective image checksum
>> -KNOWN_DISTROS = {
>> -    'fedora': {
>> -        '31': {
>> -            'x86_64':
>> -            {'checksum':
>> 'e3c1b309d9203604922d6e255c2c5d098a309c2d46215d8fc026954f3c5c27a0'},
>> -            'aarch64':
>> -            {'checksum':
>> '1e18d9c0cf734940c4b5d5ec592facaed2af0ad0329383d5639c997fdf16fe49'},
>> -            'ppc64':
>> -            {'checksum':
>> '7c3528b85a3df4b2306e892199a9e1e43f991c506f2cc390dc4efa2026ad2f58'},
>> -            's390x':
>> -            {'checksum':
>> '4caaab5a434fd4d1079149a072fdc7891e354f834d355069ca982fdcaf5a122d'},
>> +    Holds information of known distros.
>> +    """
>> +    #: A collection of known distros and their respective image
>> checksum
>> +    KNOWN_DISTROS = {
>> +        'fedora': {
>> +            '31': {
>> +                'x86_64':
>> +                {'checksum':
>> 'e3c1b309d9203604922d6e255c2c5d098a309c2d46215d8fc026954f3c5c27a0'},
>> +                'ppc64':
>> +                {'checksum':
>> '7c3528b85a3df4b2306e892199a9e1e43f991c506f2cc390dc4efa2026ad2f58'},
>> +                's390x':
>> +                {'checksum':
>> '4caaab5a434fd4d1079149a072fdc7891e354f834d355069ca982fdcaf5a122d'},
>>               }
>>           }
>>       }
>>   +    def __init__(self, name, version, arch):
>> +        self.name = name
>> +        self.version = version
>> +        self.arch = arch
>
>
> This looks a lot like
> https://github.com/avocado-framework/avocado/blob/f0996dafefa412c77c221c2d1a6fafdcba1c97b7/avocado/utils/distro.py#L34
> , although admittedly, their goals are very different.
>
>
> As a next step, in the future, I'd consider separating the data from
> the actual class and having it the LinuxDistro instances, helped by a
> registry.  Something like:
>
>
> class LinuxDistroRegistry:
>
>    def __init__(self):
>       self.distros = set()
>
>    def register(self, linux_distro):
>
>       self.distros.add(linux_distro)
>
>    def query(self, **kwargs):
>
>       ...
>
>
> registry = LinuxDistroRegistry()
>
> registry.register(LinuxDistro('fedora', '31', 'x86_64',
> 'deadbeefdeadbeef'))
>
> registry.register(LinuxDistro('fedora', '31', 'aarch64',
> 'beefdeadbeefdead'))
>
> checksum = registry.query(name='fedora', version='31',
> arch='x86_64').checksum
>
>
>> +        try:
>> +            self._info =
>> self.KNOWN_DISTROS.get(name).get(version).get(arch)
>
>
> The `AttributeError` that could be caught at the removed
> `get_known_distro_checksum()` function, could come from any of the
> `.get()`s returning `None`, which in turn would not have a `.get()`
> attribute.
>
> But now, if there's a "name", then a "version", but no "arch" entry,
> this line will set `self._info` to `None`.  This is manifested if you
> try to run a test that tries to find an aarch64 distro, such as:
>
> ./tests/venv/bin/avocado run
> tests/acceptance/boot_linux.py:BootLinuxAarch64.test_virt_tcg_gicv2
>
>
> It will result in:
>
>
> 20:38:18 ERROR| Reproduced traceback from:
> /var/lib/users/cleber/build/qemu/tests/venv/lib64/python3.9/site-packages/avocado/core/test.py:756
> 20:38:18 ERROR| Traceback (most recent call last):
> 20:38:18 ERROR|   File
> "/var/lib/users/cleber/build/qemu/tests/acceptance/avocado_qemu/__init__.py",
> line 426, in download_boot
> 20:38:18 ERROR|     checksum=self.distro.checksum,
> 20:38:18 ERROR|   File
> "/var/lib/users/cleber/build/qemu/tests/acceptance/avocado_qemu/__init__.py",
> line 334, in checksum
> 20:38:18 ERROR|     return self._info.get('checksum', None)
> 20:38:18 ERROR| AttributeError: 'NoneType' object has no attribute 'get'
> 20:38:18 ERROR|
> 20:38:18 ERROR| During handling of the above exception, another
> exception occurred:
> 20:38:18 ERROR|
> 20:38:18 ERROR| Traceback (most recent call last):
> 20:38:18 ERROR|   File
> "/var/lib/users/cleber/build/qemu/tests/acceptance/avocado_qemu/__init__.py",
> line 387, in setUp
> 20:38:18 ERROR|     self.set_up_boot()
> 20:38:18 ERROR|   File
> "/var/lib/users/cleber/build/qemu/tests/acceptance/avocado_qemu/__init__.py",
> line 455, in set_up_boot
> 20:38:18 ERROR|     path = self.download_boot()
> 20:38:18 ERROR|   File
> "/var/lib/users/cleber/build/qemu/tests/acceptance/avocado_qemu/__init__.py",
> line 431, in download_boot
> 20:38:18 ERROR|     self.cancel('Failed to download/prepare boot image')
> 20:38:18 ERROR|   File
> "/var/lib/users/cleber/build/qemu/tests/venv/lib64/python3.9/site-packages/avocado/core/test.py",
> line 988, in cancel
> 20:38:18 ERROR|     raise exceptions.TestCancel(message)
> 20:38:18 ERROR| avocado.core.exceptions.TestCancel: Failed to
> download/prepare boot image

I am not sufficiently expert on the test infra and python to be really
efficient fixing that. Can anyone help quickly to target the soft
freeze? Otherwise, today I will drop that patch and restore the code I
had in v4, just based on Cleber series. I think the refactoring can
happen later...

Thanks

Eric
>
>
> Cheers,
>
> - Cleber.
>
Cleber Rosa July 8, 2021, 5:34 p.m. UTC | #3
On 7/8/21 4:56 AM, Eric Auger wrote:
>
> I am not sufficiently expert on the test infra and python to be really
> efficient fixing that. Can anyone help quickly to target the soft
> freeze? Otherwise, today I will drop that patch and restore the code I
> had in v4, just based on Cleber series. I think the refactoring can
> happen later...


Hi Eric,


The following diff works for me:


diff --git a/tests/acceptance/avocado_qemu/__init__.py 
b/tests/acceptance/avocado_qemu/__init__.py
index af93cd63ea..b3bed00062 100644
--- a/tests/acceptance/avocado_qemu/__init__.py
+++ b/tests/acceptance/avocado_qemu/__init__.py
@@ -310,6 +310,8 @@ class LinuxDistro:
              '31': {
                  'x86_64':
                  {'checksum': 
'e3c1b309d9203604922d6e255c2c5d098a309c2d46215d8fc026954f3c5c27a0'},
+                'aarch64':
+                {'checksum': 
'1e18d9c0cf734940c4b5d5ec592facaed2af0ad0329383d5639c997fdf16fe49'},
                  'ppc64':
                  {'checksum': 
'7c3528b85a3df4b2306e892199a9e1e43f991c506f2cc390dc4efa2026ad2f58'},
                  's390x':
@@ -323,10 +325,11 @@ def __init__(self, name, version, arch):
          self.version = version
          self.arch = arch
          try:
-            self._info = 
self.KNOWN_DISTROS.get(name).get(version).get(arch)
+            info = self.KNOWN_DISTROS.get(name).get(version).get(arch)
          except AttributeError:
              # Unknown distro
-            self._info = {}
+            info = None
+        self._info = info or {}

      @property
      def checksum(self):


I've tested it with both existing and the newly introduced tests.


Cheers,

- Cleber.
Eric Auger July 8, 2021, 7:32 p.m. UTC | #4
Hi Cleber,

On 7/8/21 7:34 PM, Cleber Rosa wrote:
>
> On 7/8/21 4:56 AM, Eric Auger wrote:
>>
>> I am not sufficiently expert on the test infra and python to be really
>> efficient fixing that. Can anyone help quickly to target the soft
>> freeze? Otherwise, today I will drop that patch and restore the code I
>> had in v4, just based on Cleber series. I think the refactoring can
>> happen later...
>
>
> Hi Eric,
>
>
> The following diff works for me:
>
>
> diff --git a/tests/acceptance/avocado_qemu/__init__.py
> b/tests/acceptance/avocado_qemu/__init__.py
> index af93cd63ea..b3bed00062 100644
> --- a/tests/acceptance/avocado_qemu/__init__.py
> +++ b/tests/acceptance/avocado_qemu/__init__.py
> @@ -310,6 +310,8 @@ class LinuxDistro:
>              '31': {
>                  'x86_64':
>                  {'checksum':
> 'e3c1b309d9203604922d6e255c2c5d098a309c2d46215d8fc026954f3c5c27a0'},
> +                'aarch64':
> +                {'checksum':
> '1e18d9c0cf734940c4b5d5ec592facaed2af0ad0329383d5639c997fdf16fe49'},
>                  'ppc64':
>                  {'checksum':
> '7c3528b85a3df4b2306e892199a9e1e43f991c506f2cc390dc4efa2026ad2f58'},
>                  's390x':
> @@ -323,10 +325,11 @@ def __init__(self, name, version, arch):
>          self.version = version
>          self.arch = arch
>          try:
> -            self._info =
> self.KNOWN_DISTROS.get(name).get(version).get(arch)
> +            info = self.KNOWN_DISTROS.get(name).get(version).get(arch)
>          except AttributeError:
>              # Unknown distro
> -            self._info = {}
> +            info = None
> +        self._info = info or {}
>
>      @property
>      def checksum(self):
>
>
> I've tested it with both existing and the newly introduced tests.

Thank you for the work! Do you plan to introduce it as a fixup or do I
need to respin?

Thanks

Eric
>
>
> Cheers,
>
> - Cleber.
>
Wainer dos Santos Moschetta July 9, 2021, 7:41 p.m. UTC | #5
On 7/8/21 2:34 PM, Cleber Rosa wrote:
>
> On 7/8/21 4:56 AM, Eric Auger wrote:
>>
>> I am not sufficiently expert on the test infra and python to be really
>> efficient fixing that. Can anyone help quickly to target the soft
>> freeze? Otherwise, today I will drop that patch and restore the code I
>> had in v4, just based on Cleber series. I think the refactoring can
>> happen later...
>
>
> Hi Eric,
>
>
> The following diff works for me:
>
>
> diff --git a/tests/acceptance/avocado_qemu/__init__.py 
> b/tests/acceptance/avocado_qemu/__init__.py
> index af93cd63ea..b3bed00062 100644
> --- a/tests/acceptance/avocado_qemu/__init__.py
> +++ b/tests/acceptance/avocado_qemu/__init__.py
> @@ -310,6 +310,8 @@ class LinuxDistro:
>              '31': {
>                  'x86_64':
>                  {'checksum': 
> 'e3c1b309d9203604922d6e255c2c5d098a309c2d46215d8fc026954f3c5c27a0'},
> +                'aarch64':
> +                {'checksum': 
> '1e18d9c0cf734940c4b5d5ec592facaed2af0ad0329383d5639c997fdf16fe49'},
>                  'ppc64':
>                  {'checksum': 
> '7c3528b85a3df4b2306e892199a9e1e43f991c506f2cc390dc4efa2026ad2f58'},
>                  's390x':
> @@ -323,10 +325,11 @@ def __init__(self, name, version, arch):
>          self.version = version
>          self.arch = arch
>          try:
> -            self._info = 
> self.KNOWN_DISTROS.get(name).get(version).get(arch)
> +            info = self.KNOWN_DISTROS.get(name).get(version).get(arch)
>          except AttributeError:
>              # Unknown distro
> -            self._info = {}
> +            info = None
> +        self._info = info or {}
>
>      @property
>      def checksum(self):
>
>

Thanks for that fix, Cleber.

Acked-by: Wainer dos Santos Moschetta <wainersm@redhat.com>


> I've tested it with both existing and the newly introduced tests.
>
>
> Cheers,
>
> - Cleber.
>
Cleber Rosa July 12, 2021, 1:26 p.m. UTC | #6
On 7/8/21 3:32 PM, Eric Auger wrote:
> Hi Cleber,
>
> On 7/8/21 7:34 PM, Cleber Rosa wrote:
>> On 7/8/21 4:56 AM, Eric Auger wrote:
>>> I am not sufficiently expert on the test infra and python to be really
>>> efficient fixing that. Can anyone help quickly to target the soft
>>> freeze? Otherwise, today I will drop that patch and restore the code I
>>> had in v4, just based on Cleber series. I think the refactoring can
>>> happen later...
>>
>> Hi Eric,
>>
>>
>> The following diff works for me:
>>
>>
>> diff --git a/tests/acceptance/avocado_qemu/__init__.py
>> b/tests/acceptance/avocado_qemu/__init__.py
>> index af93cd63ea..b3bed00062 100644
>> --- a/tests/acceptance/avocado_qemu/__init__.py
>> +++ b/tests/acceptance/avocado_qemu/__init__.py
>> @@ -310,6 +310,8 @@ class LinuxDistro:
>>               '31': {
>>                   'x86_64':
>>                   {'checksum':
>> 'e3c1b309d9203604922d6e255c2c5d098a309c2d46215d8fc026954f3c5c27a0'},
>> +                'aarch64':
>> +                {'checksum':
>> '1e18d9c0cf734940c4b5d5ec592facaed2af0ad0329383d5639c997fdf16fe49'},
>>                   'ppc64':
>>                   {'checksum':
>> '7c3528b85a3df4b2306e892199a9e1e43f991c506f2cc390dc4efa2026ad2f58'},
>>                   's390x':
>> @@ -323,10 +325,11 @@ def __init__(self, name, version, arch):
>>           self.version = version
>>           self.arch = arch
>>           try:
>> -            self._info =
>> self.KNOWN_DISTROS.get(name).get(version).get(arch)
>> +            info = self.KNOWN_DISTROS.get(name).get(version).get(arch)
>>           except AttributeError:
>>               # Unknown distro
>> -            self._info = {}
>> +            info = None
>> +        self._info = info or {}
>>
>>       @property
>>       def checksum(self):
>>
>>
>> I've tested it with both existing and the newly introduced tests.
> Thank you for the work! Do you plan to introduce it as a fixup or do I
> need to respin?


Hi Eric,


Yes, I can add it as a fixup.


Thanks,

- Cleber.
diff mbox series

Patch

diff --git a/tests/acceptance/avocado_qemu/__init__.py b/tests/acceptance/avocado_qemu/__init__.py
index 81ac90bebb..af93cd63ea 100644
--- a/tests/acceptance/avocado_qemu/__init__.py
+++ b/tests/acceptance/avocado_qemu/__init__.py
@@ -299,29 +299,43 @@  def ssh_command(self, command):
                          f'Guest command failed: {command}')
         return stdout_lines, stderr_lines
 
+class LinuxDistro:
+    """Represents a Linux distribution
 
-#: A collection of known distros and their respective image checksum
-KNOWN_DISTROS = {
-    'fedora': {
-        '31': {
-            'x86_64':
-            {'checksum': 'e3c1b309d9203604922d6e255c2c5d098a309c2d46215d8fc026954f3c5c27a0'},
-            'aarch64':
-            {'checksum': '1e18d9c0cf734940c4b5d5ec592facaed2af0ad0329383d5639c997fdf16fe49'},
-            'ppc64':
-            {'checksum': '7c3528b85a3df4b2306e892199a9e1e43f991c506f2cc390dc4efa2026ad2f58'},
-            's390x':
-            {'checksum': '4caaab5a434fd4d1079149a072fdc7891e354f834d355069ca982fdcaf5a122d'},
+    Holds information of known distros.
+    """
+    #: A collection of known distros and their respective image checksum
+    KNOWN_DISTROS = {
+        'fedora': {
+            '31': {
+                'x86_64':
+                {'checksum': 'e3c1b309d9203604922d6e255c2c5d098a309c2d46215d8fc026954f3c5c27a0'},
+                'ppc64':
+                {'checksum': '7c3528b85a3df4b2306e892199a9e1e43f991c506f2cc390dc4efa2026ad2f58'},
+                's390x':
+                {'checksum': '4caaab5a434fd4d1079149a072fdc7891e354f834d355069ca982fdcaf5a122d'},
             }
         }
     }
 
+    def __init__(self, name, version, arch):
+        self.name = name
+        self.version = version
+        self.arch = arch
+        try:
+            self._info = self.KNOWN_DISTROS.get(name).get(version).get(arch)
+        except AttributeError:
+            # Unknown distro
+            self._info = {}
 
-def get_known_distro_checksum(distro, distro_version, arch):
-    try:
-        return KNOWN_DISTROS.get(distro).get(distro_version).get(arch).get('checksum')
-    except AttributeError:
-        return None
+    @property
+    def checksum(self):
+        """Gets the cloud-image file checksum"""
+        return self._info.get('checksum', None)
+
+    @checksum.setter
+    def checksum(self, value):
+        self._info['checksum'] = value
 
 
 class LinuxTest(Test, LinuxSSHMixIn):
@@ -332,24 +346,24 @@  class LinuxTest(Test, LinuxSSHMixIn):
     """
 
     timeout = 900
-    distro_checksum = None
+    distro = None
     username = 'root'
     password = 'password'
 
     def _set_distro(self):
-        distro = self.params.get(
+        distro_name = self.params.get(
             'distro',
             default=self._get_unique_tag_val('distro'))
-        if not distro:
-            distro = 'fedora'
-        self.distro = distro
+        if not distro_name:
+            distro_name = 'fedora'
 
         distro_version = self.params.get(
             'distro_version',
             default=self._get_unique_tag_val('distro_version'))
         if not distro_version:
             distro_version = '31'
-        self.distro_version = distro_version
+
+        self.distro = LinuxDistro(distro_name, distro_version, self.arch)
 
         # The distro checksum behaves differently than distro name and
         # version. First, it does not respect a tag with the same
@@ -358,13 +372,9 @@  def _set_distro(self):
         # order of precedence is: parameter, attribute and then value
         # from KNOWN_DISTROS.
         distro_checksum = self.params.get('distro_checksum',
-                                          default=self.distro_checksum)
-        if not distro_checksum:
-            distro_checksum = get_known_distro_checksum(self.distro,
-                                                        self.distro_version,
-                                                        self.arch)
+                                          default=None)
         if distro_checksum:
-            self.distro_checksum = distro_checksum
+            self.distro.checksum = distro_checksum
 
     def setUp(self, ssh_pubkey=None, network_device_type='virtio-net'):
         super(LinuxTest, self).setUp()
@@ -406,14 +416,14 @@  def download_boot(self):
         self.log.info('Downloading/preparing boot image')
         # Fedora 31 only provides ppc64le images
         image_arch = self.arch
-        if self.distro == 'fedora':
+        if self.distro.name == 'fedora':
             if image_arch == 'ppc64':
                 image_arch = 'ppc64le'
 
         try:
             boot = vmimage.get(
-                self.distro, arch=image_arch, version=self.distro_version,
-                checksum=self.distro_checksum,
+                self.distro.name, arch=image_arch, version=self.distro.version,
+                checksum=self.distro.checksum,
                 algorithm='sha256',
                 cache_dir=self.cache_dirs[0],
                 snapshot_dir=self.workdir)