spec: add specs for SOAP policy

spec/policy/soap/policy_spec.lua

@@ -0,0 +1,81 @@
+describe('policy', function()
+  describe('.rewrite', function()
+    local test_service
+    local context
+    local soap_policy
+
+    before_each(function()
+      -- Called in the code, but in busted there is no request. Mocking.
+      ngx.req.get_method = function() return 'GET' end
+
+      -- Initialize a service that mocks get_usage() so we do not need to
+      -- configure all the things we need to apply the real matching of
+      -- mapping rules.
+      -- We mock this get_usage() so it returns a different result depending
+      -- on the SOAP action we pass so we can distinguish whether it comes
+      -- from the SOAPAction header or the Content-Type one.
+      test_service = {
+        get_usage = function(_, method, soap_action_uri)
+          if method == 'GET' and soap_action_uri == '/soap_action_ctype' then
+            return { hits = 2 }
+          elseif method == 'GET' and soap_action_uri == '/soap_action_header' then
+            return { hits = 3 }
+          else
+            return {}
+          end
+        end
+      }
+
+      context = { service = test_service }
+
+      soap_policy = require('apicast.policy.soap').new()
+    end)
+
+    describe('when the SOAP action is in the SOAPAction header', function()
+      it('saves the metrics to increase in the context', function()
+        ngx.req.get_headers = function() return { SOAPAction = '/soap_action_header' } end
+
+        soap_policy:rewrite(context)
+
+        assert.same({ hits = 3 }, context.add_to_usage)
+      end)
+    end)
+
+    describe('when the SOAP action is in the Content-Type header', function()
+      it('saves the metrics to increase in the context', function()
+        ngx.req.get_headers = function()
+          return { ["Content-Type"] = "application/soap+xml?action=/soap_action_ctype" }
+        end
+
+        soap_policy:rewrite(context)
+
+        assert.same({ hits = 2 }, context.add_to_usage)
+      end)
+    end)
+
+    describe('when the SOAP action is in the SOAPAction and the Content-Type headers', function()
+      it('saves the metrics to increase in the context, ctype takes precedence', function()
+        ngx.req.get_headers = function()
+          return {
+            SOAPAction = '/soap_action_header',
+            ["Content-Type"] = "application/soap+xml?action=/soap_action_ctype"
+          }
+        end
+
+        soap_policy:rewrite(context)
+
+        assert.same({ hits = 2 }, context.add_to_usage)
+      end)
+    end)
+
+    describe('when the SOAP action is not specified', function()
+      it('does not save anything in the context', function()
+        ngx.req.get_headers = function() return {} end
+
+        soap_policy:rewrite(context)
+
+        assert.is_nil(context.add_to_usage)
+      end)
+    end)
+  end)
+end)