| public static GetOptionalString ( JToken j, string field ) : string | ||
| j | JToken | |
| field | string | |
| return | string | |
/// <summary>
/// Static function to return new instance of EnumSchema
/// </summary>
/// <param name="jtok">JSON object for enum schema</param>
/// <param name="names">list of named schema already parsed in</param>
/// <param name="encspace">enclosing namespace for the enum schema</param>
/// <returns>new instance of enum schema</returns>
internal static EnumSchema NewInstance(JToken jtok, PropertyMap props, SchemaNames names, string encspace)
{
SchemaName name = NamedSchema.GetName(jtok, encspace);
var aliases = NamedSchema.GetAliases(jtok, name.Space, name.EncSpace);
JArray jsymbols = jtok["symbols"] as JArray;
if (null == jsymbols)
{
throw new SchemaParseException("Enum has no symbols: " + name);
}
List <string> symbols = new List <string>();
IDictionary <string, int> symbolMap = new Dictionary <string, int>();
int i = 0;
foreach (JValue jsymbol in jsymbols)
{
string s = (string)jsymbol.Value;
if (symbolMap.ContainsKey(s))
{
throw new SchemaParseException("Duplicate symbol: " + s);
}
symbolMap[s] = i++;
symbols.Add(s);
}
return(new EnumSchema(name, aliases, symbols, symbolMap, props, names,
JsonHelper.GetOptionalString(jtok, "doc")));
}
/// <summary>
/// Parses the given JSON object to create a Protocol object
/// </summary>
/// <param name="jtok">JSON object</param>
/// <returns>Protocol object</returns>
private static Protocol Parse(JToken jtok)
{
string name = JsonHelper.GetRequiredString(jtok, "protocol");
string space = JsonHelper.GetOptionalString(jtok, "namespace");
string doc = JsonHelper.GetOptionalString(jtok, "doc");
var names = new SchemaNames();
JToken jtypes = jtok["types"];
var types = new List <Schema>();
if (jtypes is JArray)
{
foreach (JToken jtype in jtypes)
{
var schema = Schema.ParseJson(jtype, names, space);
types.Add(schema);
}
}
var messages = new Dictionary <string, Message>();
JToken jmessages = jtok["messages"];
if (null != jmessages)
{
foreach (JProperty jmessage in jmessages)
{
var message = Message.Parse(jmessage, names, space);
messages.Add(message.Name, message);
}
}
return(new Protocol(name, space, doc, types, messages));
}
/// <summary>
/// Creates a new field for the record
/// </summary>
/// <param name="jfield">JSON object for the field</param>
/// <param name="pos">position number of the field</param>
/// <param name="names">list of named schemas already read</param>
/// <param name="encspace">enclosing namespace of the records schema</param>
/// <returns>new Field object</returns>
private static Field createField(JToken jfield, int pos, SchemaNames names, string encspace)
{
var name = JsonHelper.GetRequiredString(jfield, "name");
var doc = JsonHelper.GetOptionalString(jfield, "doc");
var jorder = JsonHelper.GetOptionalString(jfield, "order");
Field.SortOrder sortorder = Field.SortOrder.ignore;
if (null != jorder)
{
sortorder = (Field.SortOrder)Enum.Parse(typeof(Field.SortOrder), jorder);
}
var aliases = Field.GetAliases(jfield);
var props = Schema.GetProperties(jfield);
var defaultValue = jfield["default"];
JToken jtype = jfield["type"];
if (null == jtype)
{
throw new SchemaParseException($"'type' was not found for field: name at '{jfield.Path}'");
}
var schema = Schema.ParseJson(jtype, names, encspace);
return(new Field(schema, name, aliases, pos, doc, defaultValue, sortorder, props));
}
/// <summary>
/// Parses the messages section of a protocol definition
/// </summary>
/// <param name="jmessage">messages JSON object</param>
/// <param name="names">list of parsed names</param>
/// <param name="encspace">enclosing namespace</param>
/// <returns></returns>
internal static Message Parse(JProperty jmessage, SchemaNames names, string encspace)
{
string name = jmessage.Name;
string doc = JsonHelper.GetOptionalString(jmessage.Value, "doc");
bool? oneway = JsonHelper.GetOptionalBoolean(jmessage.Value, "one-way");
PropertyMap props = Schema.GetProperties(jmessage.Value);
RecordSchema schema = RecordSchema.NewInstance(Schema.Type.Record, jmessage.Value as JObject, props, names, encspace);
JToken jresponse = jmessage.Value["response"];
var response = Schema.ParseJson(jresponse, names, encspace);
JToken jerrors = jmessage.Value["errors"];
UnionSchema uerrorSchema = null;
if (null != jerrors)
{
Schema errorSchema = Schema.ParseJson(jerrors, names, encspace);
if (!(errorSchema is UnionSchema))
{
throw new AvroException("");
}
uerrorSchema = errorSchema as UnionSchema;
}
return(new Message(name, doc, schema, response, uerrorSchema, oneway));
}
/// <summary>
/// Parses the name and namespace from the given JSON schema object then creates
/// SchemaName object including the given enclosing namespace
/// </summary>
/// <param name="jtok">JSON object to read</param>
/// <param name="encspace">enclosing namespace</param>
/// <returns>new SchemaName object</returns>
protected static SchemaName GetName(JToken jtok, string encspace)
{
String n = JsonHelper.GetOptionalString(jtok, "name"); // Changed this to optional string for anonymous records in messages
String ns = JsonHelper.GetOptionalString(jtok, "namespace");
return(new SchemaName(n, ns, encspace));
}
/// <summary>
/// Static function to return a new instance of the named schema
/// </summary>
/// <param name="jo">JSON object of the named schema</param>
/// <param name="props">dictionary that provides access to custom properties</param>
/// <param name="names">list of named schemas already read</param>
/// <param name="encspace">enclosing namespace of the named schema</param>
/// <returns></returns>
internal static NamedSchema NewInstance(JObject jo, PropertyMap props, SchemaNames names, string encspace)
{
string type = JsonHelper.GetRequiredString(jo, "type");
string doc = JsonHelper.GetOptionalString(jo, "doc");
switch (type)
{
case "fixed":
return(FixedSchema.NewInstance(jo, props, names, encspace));
case "enum":
return(EnumSchema.NewInstance(jo, props, names, encspace));
case "record":
return(RecordSchema.NewInstance(Type.Record, jo, props, names, encspace));
case "error":
return(RecordSchema.NewInstance(Type.Error, jo, props, names, encspace));
default:
NamedSchema result;
if (names.TryGetValue(type, null, encspace, doc, out result))
{
return(result);
}
return(null);
}
}
/// <summary>
/// Static function to return new instance of the fixed schema class
/// </summary>
/// <param name="jtok">JSON object for the fixed schema</param>
/// <param name="names">list of named schema already parsed in</param>
/// <param name="encspace">enclosing namespace of the fixed schema</param>
/// <returns></returns>
internal static FixedSchema NewInstance(JToken jtok, PropertyMap props, SchemaNames names, string encspace)
{
SchemaName name = NamedSchema.GetName(jtok, encspace);
var aliases = NamedSchema.GetAliases(jtok, name.Space, name.EncSpace);
return(new FixedSchema(name, aliases, JsonHelper.GetRequiredInteger(jtok, "size"), props, names,
JsonHelper.GetOptionalString(jtok, "doc")));
}
/// <summary>
/// Static function to return new instance of the record schema
/// </summary>
/// <param name="type">type of record schema, either record or error</param>
/// <param name="jtok">JSON object for the record schema</param>
/// <param name="props">dictionary that provides access to custom properties</param>
/// <param name="names">list of named schema already read</param>
/// <param name="encspace">enclosing namespace of the records schema</param>
/// <returns>new RecordSchema object</returns>
internal static RecordSchema NewInstance(Type type, JToken jtok, PropertyMap props, SchemaNames names, string encspace)
{
bool request = false;
JToken jfields = jtok["fields"]; // normal record
if (null == jfields)
{
jfields = jtok["request"]; // anonymous record from messages
if (null != jfields)
{
request = true;
}
}
if (null == jfields)
{
throw new SchemaParseException("'fields' cannot be null for record");
}
if (jfields.Type != JTokenType.Array)
{
throw new SchemaParseException("'fields' not an array for record");
}
var name = GetName(jtok, encspace);
var aliases = NamedSchema.GetAliases(jtok, name.Space, name.EncSpace);
var fields = new List <Field>();
var fieldMap = new Dictionary <string, Field>();
var fieldAliasMap = new Dictionary <string, Field>();
var result = new RecordSchema(type, name, aliases, props, fields, request, fieldMap, fieldAliasMap, names,
JsonHelper.GetOptionalString(jtok, "doc"));
int fieldPos = 0;
foreach (JObject jfield in jfields)
{
string fieldName = JsonHelper.GetRequiredString(jfield, "name");
Field field = createField(jfield, fieldPos++, names, name.Namespace); // add record namespace for field look up
fields.Add(field);
addToFieldMap(fieldMap, fieldName, field);
addToFieldMap(fieldAliasMap, fieldName, field);
if (null != field.aliases) // add aliases to field lookup map so reader function will find it when writer field name appears only as an alias on the reader field
{
foreach (string alias in field.aliases)
{
addToFieldMap(fieldAliasMap, alias, field);
}
}
}
return(result);
}
/// <summary>
/// Static function to return new instance of the fixed schema class
/// </summary>
/// <param name="jtok">JSON object for the fixed schema</param>
/// <param name="props">dictionary that provides access to custom properties</param>
/// <param name="names">list of named schema already parsed in</param>
/// <param name="encspace">enclosing namespace of the fixed schema</param>
/// <returns></returns>
internal static FixedSchema NewInstance(JToken jtok, PropertyMap props, SchemaNames names, string encspace)
{
SchemaName name = NamedSchema.GetName(jtok, encspace);
var aliases = NamedSchema.GetAliases(jtok, name.Space, name.EncSpace);
try
{
return(new FixedSchema(name, aliases, JsonHelper.GetRequiredInteger(jtok, "size"), props, names,
JsonHelper.GetOptionalString(jtok, "doc")));
}
catch (Exception e)
{
throw new SchemaParseException($"{e.Message} at '{jtok.Path}'", e);
}
}
