internal Dictionary GetBindingDataContract()

in src/WebJobs.Extensions.Http/HttpTriggerAttributeBindingProvider.cs [273:320]
35 lines of code
9 McCabe index (conditional complexity)

            internal Dictionary<string, Type> GetBindingDataContract(HttpTriggerAttribute attribute, ParameterInfo parameter)
            {
                // add contract members for POCO binding properties if binding to a POCO
                var aggregateDataContract = new Dictionary<string, Type>(StringComparer.OrdinalIgnoreCase);
                if (_isUserTypeBinding && _bindingDataProvider?.Contract != null)
                {
                    aggregateDataContract.AddRange(_bindingDataProvider.Contract);
                }

                // Mark that HttpTrigger accepts a return value. 
                aggregateDataContract["$return"] = typeof(object).MakeByRefType();

                // add contract members for any route parameters
                if (!string.IsNullOrEmpty(attribute.Route))
                {
                    var routeParameters = TemplateParser.Parse(attribute.Route).Parameters;
                    var parameters = ((MethodInfo)parameter.Member).GetParameters().ToDictionary(p => p.Name, p => p.ParameterType, StringComparer.OrdinalIgnoreCase);
                    foreach (TemplatePart routeParameter in routeParameters)
                    {
                        // don't override if the contract already includes a name
                        if (!aggregateDataContract.ContainsKey(routeParameter.Name))
                        {
                            // if there is a method parameter mapped to this parameter
                            // derive the Type from that
                            Type type;
                            if (!parameters.TryGetValue(routeParameter.Name, out type))
                            {
                                type = typeof(string);
                            }
                            aggregateDataContract[routeParameter.Name] = type;
                        }
                    }
                }

                // add headers collection to the contract
                if (!aggregateDataContract.ContainsKey(HttpHeadersKey))
                {
                    aggregateDataContract.Add(HttpHeadersKey, typeof(IDictionary<string, string>));
                }

                // add query parameter collection to binding contract
                if (!aggregateDataContract.ContainsKey(HttpQueryKey))
                {
                    aggregateDataContract.Add(HttpQueryKey, typeof(IDictionary<string, string>));
                }

                return aggregateDataContract;
            }