Add a means of retrieving attribute types

rescrv · Jul 15, 2012 · efd08ec · efd08ec
1 parent a4e03be
commit efd08ec
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Showing 3 changed files with 64 additions and 0 deletions.
diff --git a/hyperclient/hyperclient.cc b/hyperclient/hyperclient.cc
@@ -560,6 +560,34 @@ hyperclient :: loop(int timeout, hyperclient_returncode* status)
     abort();
 }
 
+enum hyperdatatype
+hyperclient :: attribute_type(const char* space, const char* name,
+                              enum hyperclient_returncode* status)
+{
+    if (maintain_coord_connection(status) < 0)
+    {
+        return HYPERDATATYPE_GARBAGE;
+    }
+
+    schema* sc = m_config->get_schema(space);
+
+    if (!sc)
+    {
+        *status = HYPERCLIENT_UNKNOWNSPACE;
+        return HYPERDATATYPE_GARBAGE;
+    }
+
+    uint16_t attrnum = sc->lookup_attr(name);
+
+    if (attrnum == sc->attrs_sz)
+    {
+        *status = HYPERCLIENT_UNKNOWNATTR;
+        return HYPERDATATYPE_GARBAGE;
+    }
+
+    return sc->attrs[attrnum].type;
+}
+
 // XXX If we lose the coord connection, this whole thing fails.
 // It would be better if we could stay alive when the coordinator dies (assuming
 // the config does not change).

diff --git a/hyperclient/hyperclient.h b/hyperclient/hyperclient.h
@@ -670,6 +670,17 @@ int64_t
 hyperclient_loop(struct hyperclient* client, int timeout,
                  enum hyperclient_returncode* status);
 
+/* Retrieve the datatype for the attribute "name" in the space "space".
+ *
+ * This will return a valid attribute, or return HYPERDATATYPE_GARBAGE if either
+ * "space" or "name" do not exist.  If it returns an error, "status" will
+ * indicate the problem.
+ */
+enum hyperdatatype
+hyperclient_attribute_type(struct hyperclient* client,
+                           const char* space, const char* name,
+                           enum hyperclient_returncode* status);
+
 /* Free an array of hyperclient_attribute objects.  This typically corresponds
  * to the value returned by the get call.
  *
@@ -814,6 +825,9 @@ class hyperclient
                       const struct hyperclient_range_query* rn, size_t rn_sz,
                       enum hyperclient_returncode* status, uint64_t* result);
         int64_t loop(int timeout, hyperclient_returncode* status);
+        // Introspect things
+        hyperdatatype attribute_type(const char* space, const char* name,
+                                     enum hyperclient_returncode* status);
 
     private:
         class completedop;

diff --git a/hyperclient/hyperclient_c_wrappers.cc b/hyperclient/hyperclient_c_wrappers.cc
@@ -316,6 +316,28 @@ hyperclient_loop(struct hyperclient* client, int timeout, hyperclient_returncode
     }
 }
 
+enum hyperdatatype
+hyperclient_attribute_type(struct hyperclient* client,
+                           const char* space, const char* name,
+                           enum hyperclient_returncode* status)
+{
+    try
+    {
+        return client->attribute_type(space, name, status);
+    }
+    catch (po6::error& e)
+    {
+        errno = e;
+        *status = HYPERCLIENT_EXCEPTION;
+        return HYPERDATATYPE_GARBAGE;
+    }
+    catch (...)
+    {
+        *status = HYPERCLIENT_EXCEPTION;
+        return HYPERDATATYPE_GARBAGE;
+    }
+}
+
 void
 hyperclient_destroy_attrs(struct hyperclient_attribute* attrs, size_t /*attrs_sz*/)
 {