Merge ~jocave/checkbox-support:improved-assertion-parsing into checkbox-support:master

[Jonathan Cave]

Given model assertions created for UC20 have a different format to previous series there was a need to rework the previous simplistic parsing functions. They previously existed in a couple of places where tests (snapd resource, fde tests) used them to identify information about the system.

This makes the parsing somewhat less crude and located in checkbox-support for reuse.

[Sheila Miguez (codersquid)]

I noticed a typo while reading this. See inline.

[Sheila Miguez (codersquid)]

I have a few minor questions.

[Jonathan Cave (jocave)]

Pushed fixes for spelling mistakes

[Sheila Miguez (codersquid)]

lgtm but maybe wait to see if maciej or spineau have any comments?

[Maciej Kisielewski (kissiel)]

I like the heuristics. I like the tests. I like the code. +1 :)

Minor nitpicks inline below.

review: Approve

[Jonathan Cave (jocave)]

Squashed the addition of a docstring in to the first commit

[Sylvain Pineau (sylvain-pineau)]

Nice use of yaml here. +1 (and I also like the tests!)

review: Approve

[Devices Certification Bot (ce-certification-qa)]

The merge was fine but running tests failed.

[xenial] [14:40:53] starting container
Device project added to xenial-testing
[focal] [14:40:58] starting container
Device project added to focal-testing
[xenial] [14:41:04] provisioning container
[focal] [14:41:12] provisioning container
[focal] [14:41:26] Starting tests...
[focal] Found a test script: ./requirements/container-tests-checkbox-support
[xenial] [14:41:29] Starting tests...
[xenial] Found a test script: ./requirements/container-tests-checkbox-support
[focal] [14:42:10] container-tests-checkbox-support: PASS
[focal] [14:42:10] Fixing file permissions in source directory
[focal] [14:42:10] Destroying container
[xenial] [14:42:13] container-tests-checkbox-support: FAIL
[xenial] output: https://paste.ubuntu.com/p/NqKFGhhbhk/
[xenial] [14:42:17] Fixing file permissions in source directory
[xenial] [14:42:18] Destroying container
[bionic] [14:42:26] starting container
Device project added to bionic-testing
[bionic] [14:42:39] provisioning container
[bionic] [14:42:57] Starting tests...
[bionic] Found a test script: ./requirements/container-tests-checkbox-support
[bionic] [14:43:45] container-tests-checkbox-support: FAIL
[bionic] output: https://paste.ubuntu.com/p/pRHrvd8nmS/
[bionic] [14:43:48] Fixing file permissions in source directory
[bionic] [14:43:48] Destroying container

review: Needs Fixing

diff --git a/checkbox_support/snap_utils/asserts.py b/checkbox_support/snap_utils/asserts.py
new file mode 100644
index 0000000..1569b22
--- /dev/null
+++ b/checkbox_support/snap_utils/asserts.py
@@ -0,0 +1,69 @@
+# Copyright 2020 Canonical Ltd.
+# All rights reserved.
+#
+# Written by:
+#    Jonathan Cave <[e-mail]>
+
+import yaml
+
+
+def decode(assertion_stream):
+    """Generate individual assertions in yaml format from a stream.
+
+    Multiple assertions are identified in the stream by a double empty line as
+    per the REST API documentation. Signatures are not verified and removed
+    so any data returned should be used only for informational purposes.
+    """
+    count = int(assertion_stream.headers['X-Ubuntu-Assertions-Count'])
+    if count > 0:
+        # split in to individual assertions
+        for assertion in assertion_stream.text.split('\n\n\n\n'):
+            # split to remove signature
+            content = assertion.split('\n\n')[0]
+            if int(yaml.__version__.split('.')[0]) < 5:
+                yield yaml.load(content)
+            else:
+                yield yaml.load(content, Loader=yaml.FullLoader)
+
+
+def model_to_resource(model_assertion):
+    """ Convert assertion yaml to flat dict for resource output."""
+    resource = {}
+    # list keys that can just be copied over
+    wanted_keys = ('type', 'authority-id', 'brand-id', 'model', 'architecture',
+                   'base', 'grade', 'sign-key-sha3-384')
+    for key, val in model_assertion.items():
+        if key in wanted_keys:
+            resource[key] = val
+    # handle other more complicated keys
+    if 'grade' in model_assertion:
+        # is in UC20 format
+        resource['grade'] = model_assertion.get('grade')
+        for snap in model_assertion['snaps']:
+            if snap['type'] in ('kernel', 'gadget'):
+                resource[snap['type']] = snap['name']
+                resource['{}_track'.format(
+                    snap['type'])] = snap['default-channel']
+    else:
+        # older formats
+        for key in ('kernel', 'gadget'):
+            val = model_assertion.get(key)
+            if '=' in val:
+                snap, track = [x.strip() for x in val.split('=')]
+                resource[key] = snap
+                resource['{}_track'.format(key)] = track
+            else:
+                resource[key] = val
+    return resource
+
+
+def serial_to_resource(serial_assertion):
+    """ Convert assertion yaml to flat dict for resource output."""
+    resource = {}
+    # list keys that can just be copied over
+    wanted_keys = ('type', 'authority-id', 'brand-id', 'model', 'serial',
+                   'sign-key-sha3-384')
+    for key, val in serial_assertion.items():
+        if key in wanted_keys:
+            resource[key] = val
+    return resource
diff --git a/checkbox_support/snap_utils/system.py b/checkbox_support/snap_utils/system.py
index 8086a4b..1c029d1 100644
--- a/checkbox_support/snap_utils/system.py
+++ b/checkbox_support/snap_utils/system.py
@@ -4,7 +4,6 @@
 # Written by:
 #    Jonathan Cave <[e-mail]>
 
-import io
 import os
 import re
 import subprocess as sp
@@ -13,6 +12,8 @@ import yaml
 import distro
 
 from checkbox_support.parsers.kernel_cmdline import parse_kernel_cmdline
+from checkbox_support.snap_utils.asserts import decode
+from checkbox_support.snap_utils.asserts import model_to_resource
 from checkbox_support.snap_utils.snapd import Snapd
 
 
@@ -28,44 +29,28 @@ def in_classic_snap():
     snap = os.getenv("SNAP")
     if snap:
         with open(os.path.join(snap, 'meta/snap.yaml')) as f:
-            for l in f.readlines():
-                if l == "confinement: classic\n":
+            for line in f.readlines():
+                if line == "confinement: classic\n":
                     return True
     return False
 
 
 def get_kernel_snap():
-    snap = None
-    assertion_stream = Snapd().get_assertions('model')
-    count = int(assertion_stream.headers['X-Ubuntu-Assertions-Count'])
-    if count > 0:
-        for line in io.StringIO(assertion_stream.text):
-            if line.count(':') == 1:
-                key, val = [x.strip() for x in line.split(':')]
-                if key == 'kernel':
-                    if '=' in val:
-                        snap, _ = [x.strip() for x in val.split('=')]
-                    else:
-                        snap = val
-                    break
-    return snap
+    model = next(decode(Snapd().get_assertions('model')), None)
+    if model:
+        # convert to resource to handle presence of track info
+        resource = model_to_resource(model)
+        return resource.get('kernel')
+    return None
 
 
 def get_gadget_snap():
-    snap = None
-    assertion_stream = Snapd().get_assertions('model')
-    count = int(assertion_stream.headers['X-Ubuntu-Assertions-Count'])
-    if count > 0:
-        for line in io.StringIO(assertion_stream.text):
-            if line.count(':') == 1:
-                key, val = [x.strip() for x in line.split(':')]
-                if key == 'gadget':
-                    if '=' in val:
-                        snap, _ = [x.strip() for x in val.split('=')]
-                    else:
-                        snap = val
-                    break
-    return snap
+    model = next(decode(Snapd().get_assertions('model')), None)
+    if model:
+        # convert to resource to handle presence of track info
+        resource = model_to_resource(model)
+        return resource.get('gadget')
+    return None
 
 
 def get_bootloader():
diff --git a/checkbox_support/snap_utils/tests/asserts_data/MODEL_FOCAL_DESKTOP.txt b/checkbox_support/snap_utils/tests/asserts_data/MODEL_FOCAL_DESKTOP.txt
new file mode 100644
index 0000000..c16f1b3
--- /dev/null
+++ b/checkbox_support/snap_utils/tests/asserts_data/MODEL_FOCAL_DESKTOP.txt
@@ -0,0 +1,19 @@
+type: model
+authority-id: generic
+series: 16
+brand-id: generic
+model: generic-classic
+classic: true
+timestamp: 2017-07-27T00:00:00.0Z
+sign-key-sha3-384: d-JcZF9nD9eBw7bwMnH61x-bklnQOhQud1Is6o_cn2wTj8EYDi9musrIT9z2MdAa
+
+AcLBXAQAAQoABgUCWYuXiAAKCRAdLQyY+/mCiST0D/0XGQauzV2bbTEy6DkrR1jlNbI6x8vfIdS8
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+l+6AMtrS4gDGHktOhwfmOMWqmhvR/INF+TjaWbsB6g==
\ No newline at end of file
diff --git a/checkbox_support/snap_utils/tests/asserts_data/MODEL_UC18.txt b/checkbox_support/snap_utils/tests/asserts_data/MODEL_UC18.txt
new file mode 100644
index 0000000..b213dc4
--- /dev/null
+++ b/checkbox_support/snap_utils/tests/asserts_data/MODEL_UC18.txt
@@ -0,0 +1,23 @@
+type: model
+authority-id: canonical
+series: 16
+brand-id: canonical
+model: ubuntu-core-18-amd64
+architecture: amd64
+base: core18
+display-name: Ubuntu Core 18 (amd64)
+gadget: pc=18
+kernel: pc-kernel=18
+timestamp: 2018-08-13T09:00:00+00:00
+sign-key-sha3-384: 9tydnLa6MTJ-jaQTFUXEwHl1yRx7ZS4K5cyFDhYDcPzhS7uyEkDxdUjg9g08BtNn
+
+AcLBXAQAAQoABgUCW37NBwAKCRDgT5vottzAEut9D/4u9lD3lFWXoHx1VQT+mUCROcFHdXQBY/PJ
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+NG54bznx12KgOT3+YiHtfE95WiXUcJUrEXAgfVBVoA==
\ No newline at end of file
diff --git a/checkbox_support/snap_utils/tests/asserts_data/MODEL_UC20.txt b/checkbox_support/snap_utils/tests/asserts_data/MODEL_UC20.txt
new file mode 100644
index 0000000..ee19f86
--- /dev/null
+++ b/checkbox_support/snap_utils/tests/asserts_data/MODEL_UC20.txt
@@ -0,0 +1,43 @@
+type: model
+authority-id: canonical
+revision: 1
+series: 16
+brand-id: canonical
+model: ubuntu-core-20-amd64-dangerous
+architecture: amd64
+base: core20
+grade: dangerous
+snaps:
+  -
+    default-channel: 20/edge
+    id: UqFziVZDHLSyO3TqSWgNBoAdHbLI4dAH
+    name: pc
+    type: gadget
+  -
+    default-channel: 20/edge
+    id: pYVQrBcKmBa0mZ4CCN7ExT6jH8rY1hza
+    name: pc-kernel
+    type: kernel
+  -
+    default-channel: latest/edge
+    id: DLqre5XGLbDqg9jPtiAhRRjDuPVa5X1q
+    name: core20
+    type: base
+  -
+    default-channel: latest/edge
+    id: PMrrV4ml8uWuEUDBT8dSGnKUYbevVhc4
+    name: snapd
+    type: snapd
+timestamp: 2020-04-29T11:18:00.0Z
+sign-key-sha3-384: 9tydnLa6MTJ-jaQTFUXEwHl1yRx7ZS4K5cyFDhYDcPzhS7uyEkDxdUjg9g08BtNn
+
+AcLBXAQAAQoABgUCWYuXiAAKCRAdLQyY+/mCiST0D/0XGQauzV2bbTEy6DkrR1jlNbI6x8vfIdS8
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+4/vYyfyvEYavhF0kQ6QGg8Cqr0EaMyw0x9/zWEO/Ll9fH/8nv9qcQq8N4AbebNvNxtGsCmJuXpSe
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+l+6AMtrS4gDGHktOhwfmOMWqmhvR/INF+TjaWbsB6g==
\ No newline at end of file
diff --git a/checkbox_support/snap_utils/tests/asserts_data/SERIAL_FOCAL_DESKTOP.txt b/checkbox_support/snap_utils/tests/asserts_data/SERIAL_FOCAL_DESKTOP.txt
new file mode 100644
index 0000000..c42add8
--- /dev/null
+++ b/checkbox_support/snap_utils/tests/asserts_data/SERIAL_FOCAL_DESKTOP.txt
@@ -0,0 +1,30 @@
+type: serial
+authority-id: generic
+brand-id: generic
+model: generic-classic
+serial: 12345678-1234-1234-1234-b4f4dc4a1f9a
+device-key:
+    AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+    AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+    AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+    AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+    AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+    AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+    AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+    AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+    AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+    AAAAAAAAAAAAAAAAAAAAAAAA
+device-key-sha3-384: AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+timestamp: 2020-03-03T16:27:34.048105Z
+sign-key-sha3-384: wrfougkz3Huq2T_KklfnufCC0HzG7bJ9wP99GV0FF-D3QH3eJtuSRlQc2JhrAoh1
+
+AcLBUgQAAQoABgUCXl6FdgAAtGsQAHSDiPo5MmtZt/Itv0dD2BR+eZ4D66SzzGLUPJv5wa8G1Ji2
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+QOddARNK0QkdYwo4Kj0FpMKxyTOW
\ No newline at end of file
diff --git a/checkbox_support/snap_utils/tests/test_asserts.py b/checkbox_support/snap_utils/tests/test_asserts.py
new file mode 100644
index 0000000..741a101
--- /dev/null
+++ b/checkbox_support/snap_utils/tests/test_asserts.py
@@ -0,0 +1,138 @@
+# Copyright 2020 Canonical Ltd.
+# All rights reserved.
+#
+# Written by:
+#    Jonathan Cave <[e-mail]>
+
+from requests.models import Response
+import unittest
+from unittest.mock import Mock
+
+from pkg_resources import resource_filename
+
+from checkbox_support.snap_utils.asserts import decode
+from checkbox_support.snap_utils.asserts import model_to_resource
+from checkbox_support.snap_utils.asserts import serial_to_resource
+
+model_focal_desktop = 'snap_utils/tests/asserts_data/MODEL_FOCAL_DESKTOP.txt'
+serial_focal_desktop = 'snap_utils/tests/asserts_data/SERIAL_FOCAL_DESKTOP.txt'
+model_uc18 = 'snap_utils/tests/asserts_data/MODEL_UC18.txt'
+model_uc20 = 'snap_utils/tests/asserts_data/MODEL_UC20.txt'
+
+
+def create_mock_response(assert_path):
+    mock_response = Mock(spec=Response)
+    mock_response.status_code = 400
+    mock_response.headers = {'X-Ubuntu-Assertions-Count': 1}
+    with open(resource_filename('checkbox_support', assert_path), 'r') as f:
+        mock_response.text = f.read()
+    return mock_response
+
+
+class TestModelAsserts(unittest.TestCase):
+
+    def test_decode_focal(self):
+        assertion_stream = create_mock_response(model_focal_desktop)
+        iter = decode(assertion_stream)
+        a = next(iter)
+        self.assertIn('type', a)
+        self.assertEqual(a['type'], 'model')
+        self.assertIn('model', a)
+        self.assertEqual(a['model'], 'generic-classic')
+        with self.assertRaises(StopIteration):
+            next(iter)
+
+    def test_decode_uc18(self):
+        assertion_stream = create_mock_response(model_uc18)
+        iter = decode(assertion_stream)
+        a = next(iter)
+        self.assertIn('type', a)
+        self.assertEqual(a['type'], 'model')
+        self.assertIn('model', a)
+        self.assertEqual(a['model'], 'ubuntu-core-18-amd64')
+        with self.assertRaises(StopIteration):
+            next(iter)
+
+    def test_decode_uc20(self):
+        assertion_stream = create_mock_response(model_uc20)
+        iter = decode(assertion_stream)
+        a = next(iter)
+        self.assertIn('type', a)
+        self.assertEqual(a['type'], 'model')
+        self.assertIn('model', a)
+        self.assertEqual(a['model'], 'ubuntu-core-20-amd64-dangerous')
+        with self.assertRaises(StopIteration):
+            next(iter)
+
+    def test_model_to_resource_uc18(self):
+        assertion_stream = create_mock_response(model_uc18)
+        iter = decode(assertion_stream)
+        a = next(iter)
+        correct_resource = {
+            'type': 'model',
+            'authority-id': 'canonical',
+            'brand-id': 'canonical',
+            'model': 'ubuntu-core-18-amd64',
+            'architecture': 'amd64',
+            'base': 'core18',
+            'sign-key-sha3-384': '9tydnLa6MTJ-jaQTFUXEwHl1yRx7ZS4K5cyFDhYDcPzhS7uyEkDxdUjg9g08BtNn',
+            'kernel': 'pc-kernel',
+            'kernel_track': '18',
+            'gadget': 'pc',
+            'gadget_track': '18'
+        }
+        self.assertDictEqual(correct_resource, model_to_resource(a))
+        with self.assertRaises(StopIteration):
+            next(iter)
+
+    def test_model_to_resource_uc20(self):
+        assertion_stream = create_mock_response(model_uc20)
+        iter = decode(assertion_stream)
+        a = next(iter)
+        correct_resource = {
+            'type': 'model',
+            'authority-id': 'canonical',
+            'brand-id': 'canonical',
+            'model': 'ubuntu-core-20-amd64-dangerous',
+            'architecture': 'amd64',
+            'base': 'core20',
+            'grade': 'dangerous',
+            'sign-key-sha3-384': '9tydnLa6MTJ-jaQTFUXEwHl1yRx7ZS4K5cyFDhYDcPzhS7uyEkDxdUjg9g08BtNn',
+            'gadget': 'pc',
+            'gadget_track': '20/edge',
+            'kernel': 'pc-kernel',
+            'kernel_track': '20/edge'
+        }
+        self.assertDictEqual(correct_resource, model_to_resource(a))
+        with self.assertRaises(StopIteration):
+            next(iter)
+
+
+class TestSerialAsserts(unittest.TestCase):
+
+    def test_decode_focal(self):
+        assertion_stream = create_mock_response(serial_focal_desktop)
+        iter = decode(assertion_stream)
+        a = next(iter)
+        self.assertIn('type', a)
+        self.assertEqual(a['type'], 'serial')
+        self.assertIn('serial', a)
+        self.assertEqual(a['serial'], '12345678-1234-1234-1234-b4f4dc4a1f9a')
+        with self.assertRaises(StopIteration):
+            next(iter)
+
+    def test_serial_to_resource_focal(self):
+        assertion_stream = create_mock_response(serial_focal_desktop)
+        iter = decode(assertion_stream)
+        a = next(iter)
+        correct_resource = {
+            'type': 'serial',
+            'authority-id': 'generic',
+            'brand-id': 'generic',
+            'model': 'generic-classic',
+            'serial': '12345678-1234-1234-1234-b4f4dc4a1f9a',
+            'sign-key-sha3-384': 'wrfougkz3Huq2T_KklfnufCC0HzG7bJ9wP99GV0FF-D3QH3eJtuSRlQc2JhrAoh1'
+        }
+        self.assertDictEqual(correct_resource, serial_to_resource(a))
+        with self.assertRaises(StopIteration):
+            next(iter)