Map service log codes

This topic lists codes for log messages that you'll see when working with map services. Each list of codes is followed by one or more examples showing how a log file would look with some of the messages.

This topic has two main parts:

• MapServer messages - A set of errors, warnings, and detailed messages written by the map service
• Carto messages - A set of detailed messages about the map drawing. Carto messages are available when Info:Detailed logging level is enabled.

MapServer messages

This following table lists log messages generated by ArcGIS Server map services and explains some of their common causes. Detailed log messages range from code 10000 - 10799 while errors and warnings range from 10800 - 10999.

Example

This example explains error messages you might see if you sent a query to a map service using a non-existent field name.

Two errors are returned. One, using code 10837 is generated by MapServer. Code 10837 is a generic code used by MapServer for all errors generated by the geodatabase. The text of the message will be "GeoDatabase Error :" followed whatever text the geodatabase provides. In this example the geodatabase generated text is "A column was specified that does not exist."

Another error message, code 100005, is also reported for the same issue. This message is system generated message. This redundancy is expected.

Carto messages

When logging is set at Info:Detailed map services provide messages from two sources: methods from the MapServer and methods from Carto. Carto is the package of objects that actually draws the map. The Carto messages refer to actual sub-processes that occur within a map server context when a client calls ExportMapImage.

Example: Connect to a map service (ArcMap client)

This example explains detailed messages you might see when connecting to a map service in ArcMap. The logs have been edited to highlight specific MapServer related messages and to remove Info2 messages.

When ArcMap connects to a map service (HTTP connection) seven requests are made: GetDefaultMapName, GetServerInfo, IsFixedScaleMap, GetSupportedImageReturnTypes and GetLegendInfo. The first request is GetDefaultMapName.

GetDefaultMapName returns the name of the active map in the map service. In this example it took MapServer 0.00032 seconds to complete the GetDefaultMapName request. The next request is GetServerInfo.

GetServerInfo returns information about the present state of the map, such as which layers are visible (turned on). In this example it took MapServer 0.06732 seconds to complete this request. Next is GetCacheDescriptionInfo.

GetCacheDescriptionInfo returns cache description information for a given map. This includes cache control info, tile cache info, tile image info, and cache type info. In this example it took MapServer 0.0003 seconds to complete this request. After making a GetCacheDescriptionInfo request, ArcMap makes a HasSingleFusedMapCache request.

HasSingleFusedMapCache determines if the map service has a fused cache. In this example it took MapServer 0.0003 seconds to complete this request. The next request is IsFixedScaleMap.

IsFixedScaleMap determines if the map service has a cache. This could be either a fused or multilayer cache. In this example it took MapServer 0.00032 seconds to complete this request. The next request is GetSupportedImageReturnTypes.

GetSupportedImageReturnTypes provides the list of supported image formats. In this example it took MapServer 0.00032 seconds to complete this request. The final request is GetLegendInfo.

GetLegendInfo returns the legend information for each layer. Each layer that supports a legend has a start and a completed messaged logged with the time it takes to package the legend information for that layer.

Example: ExportMapImage

This example explains detailed log messages that you might see when you request a dynamic map image from a map service using the ExportMapImage method. The logs have been edited to highlight specific MapServer related messages and to remove Info2 messages.

There are nine parts to the ExportMapImage process. In order, these include:

1. Receipt of request
2. Preparation of the map
3. The Geography phase - drawing of each map layer
4. The Annotation phase - drawing of graphics, labeling and annotation
5. Selection Drawing
6. Graphic Selection
7. After draw - drawing of custom features
8. Image generation
9. Process completed and result sent

After the ExportMapImage request is received by the server, the first step is to prepare the map.

Preparation includes applying the MapDescription to the map and setting up the map to draw. This includes applying any necessary geotransformations or applying a selection to any of the layers. In this example the preparation took 0.14895 seconds. The next step is to draw the map. Drawing the map encompasses a number of phases.

The first phase is the geography phase.

This is the phase in which the features of individual layers draw. Here is an example for a layer named "Layer #3".

Layer #3 is a feature layer. Therefore, a query against the database is executed (code 103021). The elapsed time for this query is 0.00332 seconds. This time is included in the elapsed time for the entire draw (code 103001). Do not add this time to the "End of layer draw (code 103001) time. The count of features being drawn, that is, the number of features within the specified map extent, for this layer is reported as 51. Also, notice that the type of renderer is reported within the method. In this example, Layer #3 is using a unique value renderer.

When the layer is a non feature layer only the Beginning of layer draw (code 103000) and End of layer draw (code 103001) are reported. Here is an example for a raster layer.

Below is an example of the log messages for a group layer along with the message indicating the end of the geography phase (code 103001).

In this example the group layer, "Group Layer" ahs two member layers: "Group Layer member #1" and "Group Layer member #2". Each member layer is drawn and messages are logged based on layer type as previously described. Notice that the end of group layer draw has a code (103003) different than the end of layer code (103001). The elapsed time for the group layer draw is the sum of the elapsed time of all the member layers within the group layer.

The next phase in drawing the map is the annotation phase. This phase includes drawing graphics, annotations and the labeling of map features.

If there are graphics within the map extent being drawn a count will be reported (code 103020).

In the example above there are 3 graphics within the map extent being drawn and it takes 0.00128 seconds to processes this. It is important to note that even if there are no graphics in the map there will still be a minimal amount of processing that the software will need to do to cycle through each phase.

Next in the annotation phase is "on-the-fly" feature labeling. Any number of layers can be labeled with any number of placement rules defined. Every time a map extent changes feature are labeled anew. This requires the labeling engine to recalculate label positions based on the rules set in the served map document. Each layer in the map that is to be labeled is listed (code 103018) along with a list of layers being used as barriers to label placement.

In this example there are two layers being labeled: "Group Layer member #1" and "Layer #1". None of the layers are used as barriers.

The last three phases are the selection draw phase, the graphics selection draw phase and the custom draw phase. The selection draw refers to any map features that are selected. In the example below there are six features selected. In most cases there will be very little for the map server to process for any of these three phases.

The final step in the ExportMapImage process is the actual image generation.

In this example it took 0.25913 seconds for the image (in this example a PNG) to be generated. The overall ExportMapImage took 1.84224 seconds to process.

It is important to note that there will be a difference how long it takes a MapServer request to process and how long it takes a binary request to be processed for the same request. This is difference is the amount of time it takes for the server to write the response to the stream.

Example: QueryFeatureData

This example shows detailed log messages that you might see when you query data in a map service using the QueryFeatureData method. The logs have been edited to highlight specific MapServer related messages and to remove Info2 messages.