refactor: add parameter: get-param-value (WIP 3)

DONE:
* create `invalid-string-param-msg`
* fix `invalid-string-param-anom` so it uses `invalid-string-param-msg`
* fix calls to `get-param-value` so they use `validate-string`
("measure" and "reportType")

TODO: make sure `validate-string` is the right validator for "measure"
and "reportType".

There is a chance I will have to create new validators for:
- measure
- report-type

modules/operation-measure-evaluate-measure/src/blaze/fhir/operation/evaluate_measure/middleware/params.clj

@@ -13,6 +13,10 @@
   (format "Invalid parameter `%s` with value `%s`. Should be a date in format YYYY, YYYY-MM or YYYY-MM-DD."
           name value))
 
+(defn- invalid-string-param-msg [name value]
+  (format "Invalid parameter `%s` with value `%s`. Should be a string."
+          name value))
+
 (defn- get-param-value-from-resource [body name]
   (when (identical? :fhir/Parameters (fhir-spec/fhir-type body))
     (some #(when (= name (:name %)) (:value %)) (:parameter body))))
@@ -58,10 +62,9 @@
    :fhir.issue/expression name))
 
 (defn- invalid-string-param-anom
-  ;; TODO: fix this
   [name value]
   (ba/incorrect
-   (invalid-date-param-msg name value)
+   (invalid-string-param-msg name value)
    :fhir/issue "value"
    :fhir/operation-outcome "MSG_PARAM_INVALID"
    :fhir.issue/expression name))
@@ -117,9 +120,9 @@
             period-end (get-required-param-value
                         request "periodEnd" coerce-date validate-date)
             measure (get-param-value
-                     request "measure" (fn [_n v] v))
+                     request "measure" (fn [_n v] v) validate-string)
             report-type (get-param-value
-                         request "reportType" coerce-report-type)
+                         request "reportType" coerce-report-type validate-string)
             subject-ref (coerce-subject-ref-param request)]
     (let [report-type (some-> report-type type/value)]
       (if (and (= :get request-method) (= "subject-list" report-type))