Sections must only appear once per config file! why???

Question

hi,

I'm getting the following exeption: "Sections must only appear once per config file. See the help topic for exceptions. "

my configuration file look like this:

<configSections>
    <sectionGroup name="point.System">
      <section name="singleInstanceCache" type="xyz.Point.System.Configuration.SingleInstanceCache, Point.System" />
    </sectionGroup>
    <sectionGroup name="point.Services">
      <sectionGroup name="xServices" type="xyz.Point.Messaging.PointServiceConfiguration.PointServices, Barcap.FIA.Point.Messaging">
        <section name="xService" type="xyz.Point.Messaging.PointServiceConfiguration.PointService, Barcap.FIA.Point.Messaging" />
      </sectionGroup>
    </sectionGroup>
  </configSections>

 <point.Services>
    <xServices>
      <xService name="Service1" type="IService" >
        <endpoints>
          <endpoint aliasName="incoming" endpointName="Subscriber"/>
          <endpoint aliasName="outgoing" endpointName="Publisher"/>
        </endpoints>
      </xService>
      <xService name="BlobService" type="IPortfolioService" >
        <endpoints>
          <endpoint aliasName="incoming" endpointName="Subscriber"/>
          <endpoint aliasName="outgoing" endpointName="Publisher"/>
        </endpoints>
      </xService>
    </xServices>
  </point.Services>

here is the code where i load it:

 /// <summary>
    /// 
    /// </summary>
    public class PointServices : ConfigurationSection
    {
        public static PointServices Get()
        {
            var t = (PointServices)ConfigurationManager.GetSection("point.Services/xServices");

            return null;
        }

        //<summary>
         //Declares a collection element represented in the following configuration sub-section
         //<singleInstances> <add .../> </singleInstances> 
         //</summary>
        [ConfigurationProperty("xServices", IsDefaultCollection = true)]
        [ConfigurationCollection(typeof(PointServices), AddItemName = "xService")]
        public PointServicesCollection Services
        {
            get
            {
                return (PointServicesCollection) base["xServices"];
            }
        }
    }



/// <summary>
    /// 
    /// </summary>
    public class PointService : ConfigurationElement
    {
        [ConfigurationProperty("name",IsRequired = true)]
        public string Name
        {
            get
            {
                return this["name"].ToString();
            }
        }

        [ConfigurationProperty("type", IsRequired = true)]
        public string Type
        {
            get
            {
                return this["type"].ToString();
            }
        }

        [ConfigurationProperty("endpoints", IsRequired = false)]
        [ConfigurationCollection(typeof(EndpointAliasCollection), AddItemName = "endpoint")]
        public EndpointAliasCollection Endpoints
        {

            get { return (EndpointAliasCollection)this["endpoints"]; }
        }
    }

if you have any idea why i'm getting this error, that would be helpful.

Thanks

Answer 1

Where is Point.System in the config file? It might just be complaining because 0 != 1 (to the computer)

Answer 2

You are trying to use a section group as a collection, and sections as items in the collection, which is not what they are intended for, hence the error.

Basically you only need to define point.Services as a section, as it does not need to contain any other sections, then define a collection property to contain configuration elements. You can update the code as follows:

Config:

<configSections>
    <section 
         name="point.Services" 
         type="xyz.Point.Messaging.PointServiceConfiguration.PointServices, Barcap.FIA.Point.Messaging" />
</configSections>

<point.Services>
   <xServices>
      <xService name="Service1" type="IService" >
         <endpoints>
            <endpoint aliasName="incoming" endpointName="Subscriber"/>
            <endpoint aliasName="outgoing" endpointName="Publisher"/>
         </endpoints>
      </xService>
      <xService name="BlobService" type="IPortfolioService" >
         <endpoints>
            <endpoint aliasName="incoming" endpointName="Subscriber"/>
            <endpoint aliasName="outgoing" endpointName="Publisher"/>
         </endpoints>
      </xService>
   </xServices>
</point.Services>

Then the code is:

    public class PointServices : ConfigurationSection
    {
        public static PointServices Get()
        {
            return (PointServices) ConfigurationManager.GetSection("point.Services");
        }

        [ConfigurationProperty("xServices", IsDefaultCollection = true)]
        [ConfigurationCollection(typeof(PointService), AddItemName = "xService")]
        public PointServicesCollection Services
        {
            get
            {
                return (PointServicesCollection) base["xServices"];
            }
        }
    }

    public class PointService : ConfigurationElement
    {
        [ConfigurationProperty("name", IsRequired = true)]
        public string Name
        {
            get
            {
                return this["name"].ToString();
            }
        }

        [ConfigurationProperty("type", IsRequired = true)]
        public string Type
        {
            get
            {
                return this["type"].ToString();
            }
        }

        [ConfigurationProperty("endpoints", IsRequired = false)]
        [ConfigurationCollection(typeof(EndpointAlias), AddItemName = "endpoint")]
        public EndpointAliasCollection Endpoints
        {

            get { return (EndpointAliasCollection) this["endpoints"]; }
        }
    }

To break it down:

• PointServices is a configuration section that maps to <point.Services> section, so the static Get() method reflects this
• PointServices defines a collection property Services which is a PointServiceCollection where the item type is PointService (NOT PointServices) and is mapped to the element name xService
• PointService elements are elements and not sections, again note that the collection property attribute defines the item type, not the container type

Hope that helps.