- More histogram work.

- Have LogStash::Search::ElasticSearch#histogram yield an error if one
  occurs
- /api/histogram reports an error now if 'q' param is missing

lib/logstash/search/elasticsearch.rb

@@ -122,14 +122,22 @@ class LogStash::Search::ElasticSearch < LogStash::Search::Base
       result.duration = Time.now - start_time
 
       @logger.info(["Got search results", 
-                   { :query => query.query_string, :duration => data["duration"],
-                     :results => data["hits"]["hits"].size }])
+                   { :query => query.query_string, :duration => data["duration"] }])
       if req.response_header.status != 200
         result.error_message = data["error"] || req.inspect
         @error = data["error"] || req.inspect
       end
 
-      data["facets"]["amazingpants"]["entries"].each do |entry|
+      entries = data["facets"]["amazingpants"]["entries"] rescue nil
+
+      if entries.nil? or !data["error"].nil?
+        # Use the error message if any, otherwise, return the whole
+        # data object as json as the error message for debugging later.
+        result.error_message = (data["error"] rescue false) || data.to_json
+        yield result
+        next
+      end
+      entries.each do |entry|
         # entry is a hash of keys 'total', 'mean', 'count', and 'key'
         hist_entry = LogStash::Search::FacetResult::Histogram.new
         hist_entry.key = entry["key"]

lib/logstash/search/facetresult/histogram.rb

@@ -9,8 +9,8 @@ class LogStash::Search::FacetResult::Histogram < LogStash::Search::FacetResult::
   attr_accessor :total
   attr_accessor :count
 
+  # sometimes a parent call to to_json calls us with args?
   def to_json(*args)
-    p :to_json => args
     return {
       "key" => @key,
       "mean" => @mean,

lib/logstash/web/server.rb

@@ -163,6 +163,11 @@ class LogStash::Web::Server < Sinatra::Base
 
   aget '/api/histogram' do
     headers({"Content-Type" => "text/plain" })
+    if params[:q].nil?
+      status 500
+      body({ "error" => "No query given (missing 'q' parameter)" }.to_json)
+      next
+    end
     format = (params[:format] or "json")
     field = (params[:field] or "@timestamp")
     interval = (params[:interval] or 3600 * 1000)
@@ -175,15 +180,18 @@ class LogStash::Web::Server < Sinatra::Base
       end
 
       begin
-        p results.results.class
         a = results.results.to_json
       rescue => e
+        status 500
+        body e.inspect
+        p :exception => e
         p e
         raise e
       end
+      status 200
       body a
     end # @backend.search
-  end # apost '/api/search'
+  end # aget '/api/histogram'
 
   aget '/*' do
     status 404 if @error