DB "canary" added - with fail/restart when connection dropped

[weathermon.git] / bin / weather-lcd

diff --git a/bin/weather-lcd b/bin/weather-lcd
index 8bf8ce56aa48c60a01bcd6aa9858e6985c6b3dde..d3283ca588677f44ef1b67292be6c69fdb432ff8 100755 (executable)
--- a/bin/weather-lcd
+++ b/bin/weather-lcd
@@ -19,7 +19,7 @@ graph_duration = uci.get(config_name,"display","graph_duration")
 if graph_duration and not(weather_db == "") then
   pcall(function ()
       local dbdriver = require "luasql.sqlite3"
-      local env = assert(dbdriver.sqlite3())
+      env = assert(dbdriver.sqlite3())
       log_con = assert(env:connect(weather_db))
     end)  
 end
@@ -155,14 +155,13 @@ function setup_pages(conn)
         write_command(conn,"screen_add "..pageid)
         write_command(conn,"screen_set "..pageid.." -cursor off -name "..pagetitle.." -duration "..graph_duration)
         write_command(conn,"widget_add "..pageid.." "..pageid..".title title")
-        write_command(conn,"widget_add "..pageid.." "..pageid..".max string")
-        write_command(conn,"widget_add "..pageid.." "..pageid..".min string")
-        for k = 3,height-1 do
-          write_command(conn,"widget_add "..pageid.." "..pageid..".place"..trim(tostring(k)).." string")
-        end
-        for k=1,width do
-          write_command(conn,"widget_add "..pageid.." "..pageid..".bar"..trim(tostring(k)).." vbar")
-        end
+        if height>2 then
+          write_command(conn,"widget_add "..pageid.." "..pageid..".max string")
+          write_command(conn,"widget_add "..pageid.." "..pageid..".min string")
+          for k = 3,height-1 do
+            write_command(conn,"widget_add "..pageid.." "..pageid..".place"..trim(tostring(k)).." string")
+          end
+        end  
         write_command(conn,"widget_set "..pageid.." "..pageid..".title \"".. pagetitle.."\"")
       end
     end
@@ -194,15 +193,16 @@ function process_graphs()
       local sensor = def["sensor"]
       local param  = def["param"]
       local pageid = sensor.."."..param
-      local cur = assert (log_con:execute(string.format("select hour,avg(value) val from (select strftime('%%Y-%%m-%%d %%H',time_stamp)||':00' hour,value from log where sensor='%s' and param='%s') group by hour order by hour desc limit 24",sensor,param)))
-      local row = cur:fetch ({}, "a")
+      local sqlcur = assert (log_con:execute(string.format("select hour,avg(value) val from (select strftime('%%Y-%%m-%%d %%H',time_stamp)||':00' hour,value from log where sensor='%s' and param='%s') group by hour order by hour desc limit 24",sensor,param)))
+      local row = sqlcur:fetch ({}, "a")
       local vals = {}
       local maxval = -99999999
       local minval =  99999999
+      local len
       for k=width,1,-1 do
         if row then
           val = row["val"] * def["scale"]
-          row = cur:fetch ({}, "a")
+          row = sqlcur:fetch ({}, "a")
         else
           val = nil  
         end  
@@ -210,17 +210,25 @@ function process_graphs()
         if val and (val > maxval) then maxval = val; end
         if val and (val < minval) then minval = val; end
       end          
+      sqlcur:close()
       minval = math.floor(minval)
-      local minvalstr = trim(tostring(minval))
       maxval = math.ceil(maxval)
-      local maxvalstr = trim(tostring(maxval))
-      local len = math.max(string.len(minvalstr),string.len(maxvalstr))
-      write_command(conn,"widget_set "..pageid.." "..pageid..".max "..trim(tostring(width-string.len(maxvalstr)+1)).." 2 "..maxvalstr)
-      for k = 3,height-1 do
-        write_command(conn,"widget_set "..pageid.." "..pageid..".place"..trim(tostring(k)).." "..trim(tostring(width-len+1)).." "..k.." \" "..string.rep("-",len-1).."\"")
-      end
-      write_command(conn,"widget_set "..pageid.." "..pageid..".min "..trim(tostring(width-string.len(minvalstr)+1)).." "..height.." "..minvalstr)
+      if height>2 then
+        local minvalstr = trim(tostring(minval))
+        local maxvalstr = trim(tostring(maxval))
+        len = math.max(string.len(minvalstr),string.len(maxvalstr))
+        write_command(conn,"widget_set "..pageid.." "..pageid..".max "..trim(tostring(width-string.len(maxvalstr)+1)).." 2 "..maxvalstr)
+        write_command(conn,"widget_set "..pageid.." "..pageid..".min "..trim(tostring(width-string.len(minvalstr)+1)).." "..height.." "..minvalstr)
+        for k = 3,height-1 do
+          write_command(conn,"widget_set "..pageid.." "..pageid..".place"..trim(tostring(k)).." "..trim(tostring(width-len+1)).." "..k.." \" "..string.rep("-",len-1).."\"")
+        end
+      else
+        len = 0
+      end    
       local m = width
+      for k=1,width do
+        write_command(conn,"widget_del "..pageid.." "..pageid..".bar"..trim(tostring(k)))
+      end
       for k = width-len,1,-1 do
         val = vals[m]
         if val then
@@ -228,12 +236,10 @@ function process_graphs()
         else
           h = 0
         end  
+        write_command(conn,"widget_add "..pageid.." "..pageid..".bar"..trim(tostring(k)).." vbar")
         write_command(conn,"widget_set "..pageid.." "..pageid..".bar"..trim(tostring(k)).." "..k.." "..height.." "..h)
         m = m - 1
       end
-      for k= m,1,-1 do
-        write_command(conn,"widget_set "..pageid.." "..pageid..".bar"..trim(tostring(k)).." 0 0 0")
-      end
     end
   end
 end
@@ -246,14 +252,19 @@ setup_pages(conn)
 
 while true do
 
-  vals = process_file()
-  process_vals(vals)
+--  pcall( function ()
 
-  if log_con then
-    process_graphs()
-  end  
+      vals = process_file()
+      process_vals(vals)
+
+      if weather_db then
+        process_graphs()
+      end  
       
-  os.execute("inotifywait -e MODIFY \""..weather_file.."\"")
-  socket.sleep(3)
+      os.execute("inotifywait -e MODIFY \""..weather_file.."\"")
+  
+--    end)
+
+    socket.sleep(3)
   
 end