[tests] Add a unit test to check for templates' versions

This test checks that there is no compatibility issue with the nodes
saved in the template files. It fails when an upgrade of a templates is
needed. Any template can still be opened even if its nodes are not up-to-
date, as they will be automatically upgraded.

tests/test_templatesVersion.py

@@ -0,0 +1,58 @@
+#!/usr/bin/env python
+# coding:utf-8
+
+from meshroom.core.graph import Graph
+from meshroom.core import pipelineTemplates, Version
+from meshroom.core.node import CompatibilityIssue, CompatibilityNode
+
+import json
+import meshroom
+
+
+def test_templateVersions():
+    """
+    This test checks that there is no compatibility issue with the nodes saved in the template files.
+    It fails when an upgrade of a templates is needed. Any template can still be opened even if its
+    nodes are not up-to-date, as they will be automatically upgraded.
+    """
+
+    assert len(pipelineTemplates) >= 1
+
+    for _, path in pipelineTemplates.items():
+        with open(path) as jsonFile:
+            fileData = json.load(jsonFile)
+
+        graphData = fileData.get(Graph.IO.Keys.Graph, fileData)
+
+        assert isinstance(graphData, dict)
+
+        header = fileData.get(Graph.IO.Keys.Header, {})
+        assert header.get("template", False)
+        nodesVersions = header.get(Graph.IO.Keys.NodesVersions, {})
+
+        for _, nodeData in graphData.items():
+            nodeType = nodeData["nodeType"]
+            assert nodeType in meshroom.core.nodesDesc
+
+            nodeDesc = meshroom.core.nodesDesc[nodeType]
+            currentNodeVersion = meshroom.core.nodeVersion(nodeDesc)
+
+            inputs = nodeData.get("inputs", {})
+            outputs = nodeData.get("outputs", {})
+            version = nodesVersions.get(nodeType, None)
+
+            compatibilityIssue = None
+
+            if version and currentNodeVersion and Version(version).major != Version(currentNodeVersion).major:
+                compatibilityIssue = CompatibilityIssue.VersionConflict
+            else:
+                for attrName, value in inputs.items():
+                    if not CompatibilityNode.attributeDescFromName(nodeDesc.inputs, attrName, value):
+                        compatibilityIssue = CompatibilityIssue.DescriptionConflict
+                        break
+                for attrName, value in outputs.items():
+                    if not CompatibilityNode.attributeDescFromName(nodeDesc.outputs, attrName, value):
+                        compatibilityIssue = CompatibilityIssue.DescriptionConflict
+                        break
+
+            assert compatibilityIssue is None