Implement Context Diff option in eos_config module

changelogs/fragments/off_box_diff_enhancement.yaml

@@ -0,0 +1,3 @@
+---
+minor_changes:
+  - eos_config - Implement off-box-diff optional feature.

docs/arista.eos.eos_config_module.rst

@@ -132,6 +132,58 @@ Parameters
                         <div>The ordered set of commands to push on to the command stack if a change needs to be made.  This allows the playbook designer the opportunity to perform configuration commands prior to pushing any changes without affecting how the set of commands are matched against the system.</div>
                 </td>
             </tr>
+            <tr>
+                <td colspan="2">
+                    <div class="ansibleOptionAnchor" id="parameter-"></div>
+                    <b>context_diff</b>
+                    <a class="ansibleOptionLink" href="#parameter-" title="Permalink to this option"></a>
+                    <div style="font-size: small">
+                        <span style="color: purple">dictionary</span>
+                    </div>
+                </td>
+                <td>
+                </td>
+                <td>
+                        <div>Specify the off-box diff options</div>
+                </td>
+            </tr>
+                                <tr>
+                    <td class="elbow-placeholder"></td>
+                <td colspan="1">
+                    <div class="ansibleOptionAnchor" id="parameter-"></div>
+                    <b>context_lines</b>
+                    <a class="ansibleOptionLink" href="#parameter-" title="Permalink to this option"></a>
+                    <div style="font-size: small">
+                        <span style="color: purple">integer</span>
+                    </div>
+                </td>
+                <td>
+                </td>
+                <td>
+                        <div>Specify The number of context lines, by default it includes all lines.</div>
+                </td>
+            </tr>
+            <tr>
+                    <td class="elbow-placeholder"></td>
+                <td colspan="1">
+                    <div class="ansibleOptionAnchor" id="parameter-"></div>
+                    <b>enable</b>
+                    <a class="ansibleOptionLink" href="#parameter-" title="Permalink to this option"></a>
+                    <div style="font-size: small">
+                        <span style="color: purple">boolean</span>
+                    </div>
+                </td>
+                <td>
+                        <ul style="margin: 0; padding: 0"><b>Choices:</b>
+                                    <li>no</li>
+                                    <li>yes</li>
+                        </ul>
+                </td>
+                <td>
+                        <div>Enable off box diff</div>
+                </td>
+            </tr>
+
             <tr>
                 <td colspan="2">
                     <div class="ansibleOptionAnchor" id="parameter-"></div>
@@ -397,6 +449,16 @@ Examples
           filename: backup.cfg
           dir_path: /home/user
 
+    - name: Get the full context diff
+      arista.eos.eos_config:
+        src: candidate.cfg
+        backup: true
+        context_diff:
+          enable: true
+        backup_options:
+          filename: backup.cfg
+          dir_path: /home/user
+
 
 
 Return Values
@@ -445,6 +507,23 @@ Common return values are documented `here <https://docs.ansible.com/ansible/late
                         <div style="font-size: smaller; color: blue; word-wrap: break-word; word-break: break-all;">[&#x27;hostname switch01&#x27;, &#x27;interface Ethernet1&#x27;, &#x27;no shutdown&#x27;]</div>
                 </td>
             </tr>
+            <tr>
+                <td colspan="1">
+                    <div class="ansibleOptionAnchor" id="return-"></div>
+                    <b>context_diff</b>
+                    <a class="ansibleOptionLink" href="#return-" title="Permalink to this return value"></a>
+                    <div style="font-size: small">
+                      <span style="color: purple">string</span>
+                    </div>
+                </td>
+                <td>when user opt for off-box-diff through context_diff option.</td>
+                <td>
+                            <div>The diff between candidate and target config.</div>
+                    <br/>
+                        <div style="font-size: smaller"><b>Sample:</b></div>
+                        <div style="font-size: smaller; color: blue; word-wrap: break-word; word-break: break-all;">&#x27; --- +++ @@ -1,7 +1,7 @@ ! Command: show running-config -! device: arista (vEOS, EOS-4.24.6M) +! device: candidate-arista-11 (vEOS, EOS-4.24.6M)&#x27;</div>
+                </td>
+            </tr>
             <tr>
                 <td colspan="1">
                     <div class="ansibleOptionAnchor" id="return-"></div>

plugins/module_utils/network/eos/utils/utils.py

@@ -10,6 +10,8 @@
 
 __metaclass__ = type
 
+import difflib
+
 
 def get_interface_number(name):
     digits = ""
@@ -82,3 +84,11 @@ def numerical_sort(string_int_list):
         as_int_list.append(int(vlan))
     as_int_list.sort()
     return list(set(as_int_list))
+
+
+def unified_diff(content1, content2, count):
+    """
+    Provide the unified diff in context to number of lines specified with count
+    """
+    unified_diff = difflib.unified_diff(content1, content2, n=count, lineterm="\n")
+    return "\n".join(unified_diff)

plugins/modules/eos_config.py

@@ -140,6 +140,16 @@
       false, the command is issued without the all keyword
     type: bool
     default: false
+  context_diff:
+    description: Specify the off-box diff options
+    type: dict
+    suboptions:
+      enable:
+        description: Enable off box diff
+        type: bool
+      context_lines:
+        description: Specify The number of context lines, by default it includes all lines.
+        type: int
   save_when:
     description:
     - When changes are made to the device running-configuration, the changes are not
@@ -272,6 +282,16 @@
     backup_options:
       filename: backup.cfg
       dir_path: /home/user
+
+- name: Get the full context diff
+  arista.eos.eos_config:
+    src: candidate.cfg
+    backup: true
+    context_diff:
+      enable: true
+    backup_options:
+      filename: backup.cfg
+      dir_path: /home/user
 """
 
 RETURN = """
@@ -310,6 +330,17 @@
   returned: when backup is true
   type: str
   sample: "22:28:34"
+context_diff:
+  description: The diff between candidate and target config.
+  returned: when user opt for off-box-diff through context_diff option.
+  type: str
+  sample: '''
+    ---
+    +++
+    @@ -1,7 +1,7 @@
+     ! Command: show running-config
+    -! device: arista (vEOS, EOS-4.24.6M)
+    +! device: candidate-arista-11 (vEOS, EOS-4.24.6M)'''
 """
 from ansible.module_utils._text import to_text
 from ansible.module_utils.basic import AnsibleModule
@@ -326,6 +357,7 @@
     load_config,
     run_commands,
 )
+from ansible_collections.arista.eos.plugins.module_utils.network.eos.utils.utils import unified_diff
 
 
 def get_candidate(module):
@@ -375,6 +407,13 @@ def main():
         parents=dict(type="list", elements="str"),
         before=dict(type="list", elements="str"),
         after=dict(type="list", elements="str"),
+        context_diff=dict(
+            type="dict",
+            options=dict(
+                enable=dict(type="bool"),
+                context_lines=dict(type="int"),
+            ),
+        ),
         match=dict(
             default="line",
             choices=["line", "strict", "exact", "none"],
@@ -453,7 +492,6 @@ def main():
 
         candidate = get_candidate(module)
         running = get_running_config(module, contents, flags=flags)
-
         try:
             response = connection.get_diff(
                 candidate=candidate,
@@ -487,12 +525,22 @@ def main():
                 replace=replace,
                 commit=commit,
             )
-
             result["changed"] = True
-
             if module.params["diff_against"] == "session":
                 if "diff" in response:
-                    result["diff"] = {"prepared": response["diff"]}
+                    context_diff = module.params.get("context_diff")
+                    if context_diff and context_diff.get("enable"):
+                        if context_diff.get("context_lines"):
+                            count = context_diff.get("context_lines")
+                        else:
+                            count = max(len(candidate), len(running))
+                        result["context_diff"] = unified_diff(
+                            candidate.split("\n"),
+                            running.split("\n"),
+                            count,
+                        )
+                    else:
+                        result["diff"] = {"prepared": response["diff"]}
                 else:
                     result["changed"] = False
 
@@ -618,7 +666,6 @@ def main():
             result["warnings"].append(msg)
         else:
             result["warnings"] = msg
-
     module.exit_json(**result)
 
 

tests/integration/targets/eos_config/templates/defaults/candidate.j2

@@ -0,0 +1,8 @@
+! Command: show running-config
+!
+interface Ethernet2
+   description "This is candidate config sample"
+   shutdown
+   no switchport
+!
+end

tests/integration/targets/eos_config/tests/cli/backup.yaml

@@ -97,6 +97,22 @@
     that:
       - result.changed == true
 
+- name: get the context diff with backup config
+  become: true
+  register: result
+  arista.eos.eos_config:
+    src: defaults/candidate.j2
+    backup: true
+    context_diff:
+      enable: true
+      context_lines: 10
+    backup_options:
+      filename: running_backup.cfg
+
+- ansible.builtin.assert:
+    that:
+      - result.context_diff is defined
+
 - name: check if the backup file-2 exist
   ansible.builtin.find:
     paths: "{{ role_path }}/backup/backup.cfg"

tests/unit/modules/network/eos/fixtures/eos_candidate.cfg

@@ -0,0 +1,7 @@
+hostname switch02
+!
+interface Ethernet1
+   description test interface
+   no shutdown
+!
+ip routing

tests/unit/modules/network/eos/test_eos_config.py

@@ -299,6 +299,42 @@ def test_eos_config_src_replace(self):
             result["commands"],
         )
 
+    def test_eos_config_context_diff(self):
+        src = load_fixture("eos_candidate.cfg")
+        args = dict(
+            src=src,
+            backup=True,
+            context_diff=dict(enable=True),
+            backup_options=dict(
+                filename="backup.cfg",
+                dir_path="./",
+            ),
+        )
+        set_module_args(args)
+        self.conn.get_diff = MagicMock(
+            return_value=self.cliconf_obj.get_diff(src, self.running_config),
+        )
+        result = self.execute_module(changed=True)
+        self.assertIn("context_diff", result)
+
+    def test_eos_config_context_diff_lines(self):
+        src = load_fixture("eos_candidate.cfg")
+        args = dict(
+            src=src,
+            backup=True,
+            context_diff=dict(enable=True, context_lines=10),
+            backup_options=dict(
+                filename="backup.cfg",
+                dir_path="./",
+            ),
+        )
+        set_module_args(args)
+        self.conn.get_diff = MagicMock(
+            return_value=self.cliconf_obj.get_diff(src, self.running_config),
+        )
+        result = self.execute_module(changed=True)
+        self.assertIn("context_diff", result)
+
     def test_eos_config_lines_block(self):
         lines = ["hostname switch01", "ip domain-name eng.ansible.com"]
         args = dict(lines=lines, replace="block")