/// <summary>
/// Static class to return new instance of schema object
/// </summary>
/// <param name="jtok">JSON object</param>
/// <param name="names">list of named schemas already read</param>
/// <param name="encspace">enclosing namespace of the schema</param>
/// <returns>new Schema object</returns>
internal static Schema ParseJson(JToken jtok, SchemaNames names, string encspace)
{
if (null == jtok)
{
throw new ArgumentNullException("j", "j cannot be null.");
}
if (jtok.Type == JTokenType.String) // primitive schema with no 'type' property or primitive or named type of a record field
{
string value = (string)jtok;
PrimitiveSchema ps = PrimitiveSchema.NewInstance(value);
if (null != ps)
{
return(ps);
}
NamedSchema schema = null;
if (names.TryGetValue(value, null, encspace, out schema))
{
return(schema);
}
throw new SchemaParseException("Undefined name: " + value);
}
if (jtok is JArray) // union schema with no 'type' property or union type for a record field
{
return(UnionSchema.NewInstance(jtok as JArray, null, names, encspace));
}
if (jtok is JObject) // JSON object with open/close parenthesis, it must have a 'type' property
{
JObject jo = jtok as JObject;
JToken jtype = jo["type"];
if (null == jtype)
{
throw new SchemaParseException("Property type is required");
}
var props = Schema.GetProperties(jtok);
if (jtype.Type == JTokenType.String)
{
string type = (string)jtype;
if (type.Equals("array"))
{
return(ArraySchema.NewInstance(jtok, props, names, encspace));
}
if (type.Equals("map"))
{
return(MapSchema.NewInstance(jtok, props, names, encspace));
}
Schema schema = PrimitiveSchema.NewInstance((string)type, props);
if (null != schema)
{
return(schema);
}
return(NamedSchema.NewInstance(jo, props, names, encspace));
}
else if (jtype.Type == JTokenType.Array)
{
return(UnionSchema.NewInstance(jtype as JArray, props, names, encspace));
}
}
throw new AvroTypeException("Invalid JSON for schema: " + jtok);
}
/// <summary>
/// Checks if this schema can read data written by the given schema. Used for decoding data.
/// </summary>
/// <param name="writerSchema">writer schema</param>
/// <returns>true if this and writer schema are compatible based on the AVRO specification, false otherwise</returns>
public override bool CanRead(Schema writerSchema)
{
return(writerSchema.Tag == Schema.Type.Union || MatchingBranch(writerSchema) >= 0);
}
/// <summary>
/// Returns true if and only if data written using writerSchema can be read using the current schema
/// according to the Avro resolution rules.
/// </summary>
/// <param name="writerSchema">The writer's schema to match against.</param>
/// <returns>True if and only if the current schema matches the writer's.</returns>
public virtual bool CanRead(Schema writerSchema)
{
return(Tag == writerSchema.Tag);
}
