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Couchbase Lite 2 + JsonConvert

The following code sample writes a simple object to a couchbase lite (version 2) database and reads all objects afterwards. This is what you can find in the official documentation here
This is quite a lot of manual typing since every property of every object must be transferred to the MutableObject.
class Program
{
static void Main(string[] args)
{
Couchbase.Lite.Support.NetDesktop.Activate();
const string DbName = "MyDb";
var db = new Database(DbName);
var item = new Item { Name = "test", Value = 5 };
// Serialization HERE
var doc = new MutableDocument();
doc.SetString("Name", item.Name);
doc.SetInt("Value", item.Value);
db.Save(doc);
using (var qry = QueryBuilder.Select(SelectResult.All())
.From(DataSource.Database(db)))
{
foreach (var result in qry.Execute())
{
var resultItem = new Item
{
// Deserialization HERE
Name = result[DbName].Dictionary.GetString("Name"),
Value = result[DbName].Dictionary.GetInt("Value")
};
Console.WriteLine(resultItem.Name);
}
}
Console.ReadKey();
}
class Item
{
public string Name { get; set; }
public int Value { get; set; }
}
}
From my research Couchbase lite uses JsonConvert internally, so there might be a way to simplify all that with the help of JsonConvert.
Anything like:
var json = JsonConvert.SerializeObject(item);
var doc = new MutableDocument(json); // No overload to provide raw JSON
or maybe
var data = JsonConvert.SerializeToDict(item); // JsonConvert does not provide this
var doc = new MutableDocument(data);
Is there or is this some kind of optimization and the preferred approach is by intend?

People ask about this quite often, but Couchbase Lite does not actually store JSON strings in the database. They are stored in a different format so this would not give the benefit that you think (the JSON would need to be reparsed and then broken down into the other format). I'd been pushing for a way to serialize classes directly instead of going through dictionary objects (which seems like the ultimate goal here) but our priority is on things that enterprise clients want and this doesn't seem to be one of them. Note that for it to make it in, it needs to be implemented in C# Java and Objective-C / Swift.

I don't know about JsonConvert but there seems to be a constructor that takes IDictionary<string, object> as argument. So I would try something like this (brain-compiled):
MutableDocument CreateDocument(object data)
{
if (data == null) return null;
var propertyValues = new Dictionary<string, object>();
foreach (var property in data.GetType().GetProperties(BindingFlags.Public | BindingFlags.Instance))
{
propertyValues[property.Name] = property.GetValue(data);
}
return new MutableDocument(propertyValues);
}
See if this works.

return stored proc results as XML

I am writing an interface in a Web service that returns XML output. The output is queried from a MS SQL database by calling stored procedure. While the stored procedure itself is not returning XML, and I don't have any control over it, I need to return the result set as XML.
Right now, I'm using XmlWriter. Is there an easier, elegant way to do this?
StringBuilder sbLog = new StringBuilder();
XmlWriter writer = XmlWriter.Create(sbLog);
writer.WriteStartDocument();
writer.WriteStartElement("LogSet");
while (sqlRdr.Read())
{
writer.WriteStartElement("Log");
writer.WriteStartElement("EntryID");
writer.WriteValue(sqlRdr["EntryID"].ToString());
writer.WriteEndElement();
//and so on

Yeah XDocument is probably a cleaner interface. It would look something like this:
var doc = new XDocument(
new XElement("LogSet",
new XElement("EntryID", sqlRdr["EntryID"].ToString()),
new XElement(...)
)
);
// save it to a file
doc.Save(pathToDoc);
// or just return it
return doc.ToString();

I'm not sure about it's elegance (I guess that partially depends on how many times you need to reproduce this sort of thing in your code), but I wrote an XmlDataReader a while back that converts tabular data in an IDataReader into an Xml result without the need to create a secondary document/string. As WebServices could return an XmlNode (rather than XmlReader) the second class XmlNodeFactory does that conversion.
Here is the Gist for XmlDataReader
And for the XmlNodeFactory
Usage is something like:
[WebMethod]
public XmlNode GetFeaturedItems(string storeId)
{
var xmlReader = new XmlDataReader(
_db.GetFeaturedItems(storeId),
MyXmlNames.FeaturedItemsNamespace)
{
IncludeIndexField = false,
IncludeResultLevel = false,
RootElementName = "FeaturedItems",
RowElementNameFormat = "Item"
};
return XmlNodeFactory.Create(xmlReader);
}

Find differences between two json objects

Are there any libraries in .Net to help compare and find differences between two json objects? I've found some solutions available for JavaScript, but nothing interesting for C#. The point of my question is to create json with changes marked in some way, based on the comparison. So that the user could see where the changes are.

using Microsoft.XmlDiffPatch;
using Newtonsoft.Json;
Convert each json to xml and use MS XmlDiff libary. Available on nuget. Differences are given in another xml doc which here I write to the console. This is suitable for unit testing for example.
public bool CompareJson(string expected, string actual)
{
var expectedDoc = JsonConvert.DeserializeXmlNode(expected, "root");
var actualDoc = JsonConvert.DeserializeXmlNode(actual, "root");
var diff = new XmlDiff(XmlDiffOptions.IgnoreWhitespace |
XmlDiffOptions.IgnoreChildOrder);
using (var ms = new MemoryStream())
using (var writer = new XmlTextWriter(ms, Encoding.UTF8))
{
var result = diff.Compare(expectedDoc, actualDoc, writer);
if (!result)
{
ms.Seek(0, SeekOrigin.Begin);
Console.WriteLine(new StreamReader(ms).ReadToEnd());
}
return result;
}
}

I have used different JSON objects than those in your example but it will apply to your case correctly.
private static string GetJsonDiff(string action, string existing, string modified, string objectType)
{
// convert JSON to object
JObject xptJson = JObject.Parse(modified);
JObject actualJson = JObject.Parse(existing);
// read properties
var xptProps = xptJson.Properties().ToList();
var actProps = actualJson.Properties().ToList();
// find differing properties
var auditLog = (from existingProp in actProps
from modifiedProp in xptProps
where modifiedProp.Path.Equals(existingProp.Path)
where !modifiedProp.Value.ToString().Equals(existingProp.Value.ToString())
select new AuditLog
{
Field = existingProp.Path,
OldValue = existingProp.Value.ToString(),
NewValue = modifiedProp.Value.ToString(),
Action = action, ActionBy = GetUserName(),
ActionDate = DateTime.UtcNow.ToLongDateString(),
ObjectType = objectType
}).ToList();
return JsonConvert.SerializeObject(auditLog);
}

I think your best bet is to use JSON.NET to create two JSON objects, then recursively loop through the tree, comparing each node to see if it exists and is equal while you go.

I think the best way to go here is to create objects using newtonsoft json.http://www.nuget.org/packages/newtonsoft.json/
So, you will have two objects of the same type, which you can easily compare and mark the differences.

private IEnumerable<JProperty> JSONCompare(string expectedJSON, string actualJSON)
{
// convert JSON to object
JObject xptJson = JObject.Parse(expectedJSON);
JObject actualJson = JObject.Parse(actualJSON);
// read properties
var xptProps = xptJson.Properties().ToList();
var actProps = actualJson.Properties().ToList();
// find missing properties
var missingProps = xptProps.Where(expected => actProps.Where(actual => actual.Name == expected.Name).Count() == 0);
return missingProps;
}

Parsing large json

I'm trying to parse a json file and then operate on it to insert data into a SQL Server 2008 Database.
Example:
var sr = new StreamReader("C:\\path to file\file.json");
var json = JsonSerializer.SerializeToString(sr);
var o = JsonObject.Parse(json);
But I always get this error at the second line - "Timeouts are not supported on this stream."
The Json file looks like this:
"main":{
"prg": [
{
"Id": 1,
"name": "A&E",
more fields
}
"prg": [
{
"Id": 2,
"name": "asda",
more fields
}
}
I need to make something like this
foreach (prg in main)
entity.id = prg.id
entity.name = prg.name
How can I do this and why I get that timeout exception?
EDIT: To better understand my question this is how I do for an XML file
XmlDocument sourceDoc = new XmlDocument();
sourceDoc.Load(SourcesElement2); // where SourcesElement2 is the path to my XML
XmlNodeList prg = sourceDoc.GetElementsByTagName("prg");
foreach (XmlNode item in prg)
{
entity.Name= item.SelectSingleNode("name").InnerText;
...
}
I have converted the XML to Json and I want to do same thing. For every "prg" node in the Json File insert a new item in the database
EDIT2:
This is what I've done.
using (
StreamReader stream =
File.OpenText(
"C:\\path\\Sources.json")
)
{
JObject sources = (JObject) JToken.ReadFrom(new JsonTextReader(stream));
var a = sources["on"];
var b = a["sources"];
var c = b["prgs"];
foreach (var item in c)
{
var d= item.SelectToken("prg");
// Here d is null
}
I have the same question as the one from above. For every "prg" node in the Json File insert a new item in the database. How can I do this ? ( path to prg is on/sources/prgs/ )

I don't think you want to serialize the stream.
JsonSerializer.SerializeToString(sr)
You want to deserialize from the stream.
JsonSerializer.Deserialize
You might want to use JsonReader for performance reasons.
Your XML example load the whole file in the memory - you don't want to do that for large documents. reader.Read() pattern is better suited for processing large files.

For everyone with the same problem here is what I've done ( NOTE: this is just an example )
By the way, thank you for everyone who tried to answer my question and I'm sorry for my mistakes.
List<string> d = new List<string>();
using (
StreamReader stream =
File.OpenText(
"C:\\path\\Sources.json")
)
{
JObject sources = (JObject) JToken.ReadFrom(new JsonTextReader(stream));
var a = sources["on"];
var b = a["sources"];
var c = b["prgs"];
foreach (JObject item in c["prg"].ToList())
{
d.Add(item.Value<string>("name"));
}
}
//part below is just for testing
foreach (var VARIABLE in d)
{
Console.WriteLine(VARIABLE);
}
Console.ReadLine();

I would approach it by converting that JSON object into a C# class and then applying logic to the C# object and/or use DataTables
[Note: There are solutions online that show you would to easily pass an Object or List<Object> into a DataTable and then pass it "easily" to SQL]
The first step is still your hiccup in either solution, how do I pull in a large JSON string from filesystem?
if you have the JSON, use json2csharp.com and/or jsonutils.com to retrieve the classes in order to Deserialize it to your object.
StreamReader re = new StreamReader(#"C:\path to file\file.json");
JsonTextReader reader = new JsonTextReader(re);
YourClass DeserializedObject = se.Deserialize<YourClass>(reader);
Console.WriteLine(DeserializeObject.SomeProperty);

Best practice create a C# Object which reflect and generate a Serialized string

This question may be asked or answered before but I feel that none of the hits really apply.
I would like to create a little class with attributes which will correspond to name and attributes in a output familiar to xml stream. The class should help the program to create a xml-alike string.
string test = "<graph caption='SomeHeader' attribute9='#someotherinfo'>" +
"<set name='2004' value='37800' color='AFD8F8' />" +
"<set name='2005' value='21900' color='F6BD0F' />" +
"<set name='2006' value='32900' color='8BBA00' />" +
"<set name='2007' value='39800' color='FF8E46' />" +
"</graph>";
I think you got the idea. I have a static amount of known attributes which will be used in the tags. The only Tags here is set and graph.
I would like to do something like this,
Helper o = new Helper()
List<Tag> tag = new List<Tag>();
foreach (var someitem in somedatabaseresult)
{
tag.Add(New Graph() { Caption = someitem.field , attribute9 = someitem.otherField });
foreach (var detail in someitem)
{
tag.Add(new Set() { name = detail.Year, value = detail.Value color = detail.Color });
}
}
o.Generate(); // Which will create the structure of result sample above
// and for future extension..
// o.GenerateXml();
// o.GenerateJson();
Please remember that this code is pesudo, just taken from my head. A result of that I have some ideas but it take a day to code and test what best (or whorse).
What would be best practice to solve this task?
[EDIT]
This mysterious "Helper" is the (unluckily typed) class who contains a list of Graph, a list of Set and also (what I think about) contains all available attributes per Graph/Set object. The work of the foreach-loops above are mentioned to fill the Helper class with the data.
[EDIT2]
Result here,
https://gist.github.com/1233331

Why not just create a couple of classes: Graph and Set. Graph would have a property of List<Set>.
In your foreach you can then create an instance or Graph and add instances of Set to its list.
When you're done use the XML Serializer to serialize the Graph object out to XML. Nice and easy to then output to another format as well if your needs change later e.g. serialize to JSON.
Edit following comment:
From top my head so may not be 100% correct...
var myGraph = BuildMeAGraph();
var serializer = new XmlSerializer(typeof(Graph));
var writer = XmlWriter.Create("myfile.xml");
serializer.Serialize(writer, myGraph);
But something like that should write it out to a file. If you want the XML in memory then write it out to an XMLTextWriter based on a memory stream instead and then you can write the contents to a string variable or do whatever you need with it.

If you want to create an XML, out of the object tree, then I think, you could try this:
XDocument doc = new XDocument
(
somedatabaseresult.Select
( someitem =>
new XElement("graph",
new XAttribute("Caption", ""),
new XAttribute("attribute9", "#something"),
someitem.Select
(detail =>
new XElement("Set",
new XAttribute("name", "2003"),
new XAttribute("value", "34784"),
new XAttribute("color", "#003300")
)
)
);
//save to file as XML
doc.Save("output.xml");
//save to local variable as XML string
string test = doc.ToString();
I wrote the save value for tags, as you've used in your code. However, I think you would like this:
new XAttribute("name", detail.name),
new XAttribute("value", detail.value),
new XAttribute("color", detail.color)
Or whatever value you want to give to each attribute from the object detail.

Use the XmlSerializer.

I'd use the ExpandoObject, but I don't see the reason for what you are doing.