Flat Vert.x YAML Config - yaml

We're wondering if it possible to flat YAML config object? For example, our config files looks like
vertx:
verticle:
instance: 1
metrics:
options:
enabled: true
And we would like to access to our config values with only one operation, for example:
config.getInteger("vertx.verticle.instance")
instead of having to do:
config.getJsonObject("vertx").getJsonObject("verticle").getInteger("integer")
Thanks.

Vert.x supports Json Pointers from RFC6901. You could do:
JsonPointer pointer = JsonPointer.from("/vertx/verticle/instance");
Integer instance = (Integer) pointer.queryJson(config);

While the API doesn't support it directly, it seems easy enough to implement yourself:
public class FlatConfig {
private final JsonObject root;
public FlatConfig(JsonObject root) {
this.root = root;
}
private JsonObject walk(String[] path) {
JsonObject cur = root;
// skip last element since it contains the value
for (int i = 0; i < path.length - 2; i++) {
cur = cur.getJsonObject(path[i]);
}
return cur;
}
public Integer getInteger(String path) {
final String[] splitPath = path.split(".");
return walk(splitPath).getInteger(splitPath[splitPath.length - 1]);
}
}
You can add other methods for retrieving other types as necessary.

Related

Is there a way to avoid the truncation of attached properties when using Appcenter with Xamarin?

Here's my code:
Crashes.TrackError(ex,
new Dictionary<string, string> {
{"RunQuery", "Exception"},
{"sql", s },
{"Device Model", DeviceInfo.Model },
{"Exception", ex.ToString()}
});
Everything works but I find that Appcenter limits the length of the parameters to 125 characters so it's useless for me as I can never see all of the sql or the ex string.
Has anyone found a way to get around this?
I ran into the same problem. My solution was to break my string into groups of 125 character strings and iterate through while logging. I chatted with AppCenter support. They have no way of extending this length currently.
Here is a scrubbed version of my code:
var tokenChunks = LoggingHelper.SplitBy(extremelyLongString, 120);
string title = "Long string here";
var props = new Dictionary<string, string>();
int item = 0;
foreach(string chunk in tokenChunks)
{
string chunkIndex = string.Format("item: {0}", item++);
props.Add(chunkIndex, chunk);
}
Analytics.TrackEvent(title, props);
Where the LoggingHelper class is:
public static class LoggingHelper
{
public static IEnumerable<string> SplitBy(this string str, int chunkLength)
{
if (String.IsNullOrEmpty(str)) throw new ArgumentException();
if (chunkLength < 1) throw new ArgumentException();
for (int i = 0; i < str.Length; i += chunkLength)
{
if (chunkLength + i > str.Length)
chunkLength = str.Length - i;
yield return str.Substring(i, chunkLength);
}
}
}
I should give credit to this post https://stackoverflow.com/a/8944374/117995 by #oleksii for the SplitBy method.

Java - For loop within ArrayList<String> method only returns one element

I am trying to use an ArrayList of string values from one table, modify the strings based on whether or not the string ends with ".tif" or ".tiff", then transfer the resulting strings to a new table. However, when I invoke this method, the new table only receives the first modified string. I'm not sure what is wrong with my logic, the first element of the original table would be checked to see if it satisfies a condition (either ending in ".tif" or ".tiff") then from there that string would be modified, added to the ArrayList fData, then iterate to the next table value. I don't understand why the method doesn't return more than one element contained within fData?
public ArrayList<String> getTableData() {
StringBuilder str = new StringBuilder();
String fString = null;
ArrayList<String> fData = new ArrayList<String>();
while(filePaths != null) {
int size = filePaths.size();
for (int i = 0; i <= size; i++) {
String pathName = filePaths.get(i);
if (pathName.endsWith(".tif")) {
int pathLength = pathName.length();
str = new StringBuilder(filePaths.get(i));
str.insert(pathLength - 4, "_Data");
fString = str.toString();
fData.add(fString);
tableModel2.addRow(new String[] { fString });
return fData;
}
else if (pathName.endsWith(".tiff")) {
int pathLength = pathName.length();
str = new StringBuilder(filePaths.get(i));
str.insert(pathLength - 5, "_Data");
fString = str.toString();
fData.add(fString);
tableModel2.addRow(new String[] { fString });
return fData;
}
}
tableModel2.fireTableDataChanged();
}
return null;
}
`
It appears that you are returning from getTableData() as soon as you do a single replacement. Instead, you should return only after having iterated over every file path.
Remove the return statements inside the loops and instead replace return null at the end with return fData.

Dynamically choose which properties to get using Linq

I have an MVC application with a dynamic table on one of the pages, which the users defines how many columns the table has, the columns order and where to get the data from for each field.
I have written some very bad code in order to keep it dynamic and now I would like it to be more efficient.
My problem is that I don't know how to define the columns I should get back into my IEnumerable on runtime. My main issue is that I don't know how many columns I might have.
I have a reference to a class which gets the field's text. I also have a dictionary of each field's order with the exact property It should get the data from.
My code should look something like that:
var docsRes3 = from d in docs
select new[]
{
for (int i=0; i<numOfCols; i++)
{
gen.getFieldText(d, res.FieldSourceDic[i]);
}
};
where:
docs = List from which I would like to get only specific fields
res.FieldSourceDic = Dictionary in which the key is the order of the column and the value is the property
gen.getFieldText = The function which gets the entity and the property and returns the value
Obviously, it doesn't work.
I also tried
StringBuilder fieldsSB = new StringBuilder();
for (int i = 0; i < numOfCols; i++)
{
string field = "d." + res.FieldSourceDic[i] + ".ToString()";
if (!string.IsNullOrEmpty(fieldsSB.ToString()))
{
fieldsSB.Append(",");
}
fieldsSB.Append(field);
}
var docsRes2 = from d in docs
select new[] { fieldsSB.ToString() };
It also didn't work.
The only thing that worked for me so far was:
List<string[]> docsRes = new List<string[]>();
foreach (NewOriginDocumentManagment d in docs)
{
string[] row = new string[numOfCols];
for (int i = 0; i < numOfCols; i++)
{
row[i] = gen.getFieldText(d, res.FieldSourceDic[i]);
}
docsRes.Add(row);
}
Any idea how can I pass the linq the list of fields and it'll cut the needed data out of it efficiently?
Thanks, Hoe I was clear about what I need....
Try following:
var docsRes3 = from d in docs
select (
from k in res.FieldSourceDic.Keys.Take(numOfCols)
select gen.getFieldText(d, res.FieldSourceDic[k]));
I got my answer with some help from the following link:
http://www.codeproject.com/Questions/141367/Dynamic-Columns-from-List-using-LINQ
First I created a string array of all properties:
//Creats a string of all properties as defined in the XML
//Columns order must be started at 0. No skips are allowed
StringBuilder fieldsSB = new StringBuilder();
for (int i = 0; i < numOfCols; i++)
{
string field = res.FieldSourceDic[i];
if (!string.IsNullOrEmpty(fieldsSB.ToString()))
{
fieldsSB.Append(",");
}
fieldsSB.Append(field);
}
var cols = fieldsSB.ToString().Split(',');
//Gets the data for each row dynamically
var docsRes = docs.Select(d => GetProps(d, cols));
than I created the GetProps function, which is using my own function as described in the question:
private static dynamic GetProps(object d, IEnumerable<string> props)
{
if (d == null)
{
return null;
}
DynamicGridGenerator gen = new DynamicGridGenerator();
List<string> res = new List<string>();
foreach (var p in props)
{
res.Add(gen.getFieldText(d, p));
}
return res;
}

What does ExpressionVisitor.Visit<T> Do?

Before someone shouts out the answer, please read the question through.
What is the purpose of the method in .NET 4.0's ExpressionVisitor:
public static ReadOnlyCollection<T> Visit<T>(ReadOnlyCollection<T> nodes, Func<T, T> elementVisitor)
My first guess as to the purpose of this method was that it would visit each node in each tree specified by the nodes parameter and rewrite the tree using the result of the elementVisitor function.
This does not appear to be the case. Actually this method appears to do a little more than nothing, unless I'm missing something here, which I strongly suspect I am...
I tried to use this method in my code and when things didn't work out as expected, I reflectored the method and found:
public static ReadOnlyCollection<T> Visit<T>(ReadOnlyCollection<T> nodes, Func<T, T> elementVisitor)
{
T[] list = null;
int index = 0;
int count = nodes.Count;
while (index < count)
{
T objA = elementVisitor(nodes[index]);
if (list != null)
{
list[index] = objA;
}
else if (!object.ReferenceEquals(objA, nodes[index]))
{
list = new T[count];
for (int i = 0; i < index; i++)
{
list[i] = nodes[i];
}
list[index] = objA;
}
index++;
}
if (list == null)
{
return nodes;
}
return new TrueReadOnlyCollection<T>(list);
}
So where would someone actually go about using this method? What am I missing here?
Thanks.
It looks to me like a convenience method to apply an aribitrary transform function to an expression tree, and return the resulting transformed tree, or the original tree if there is no change.
I can't see how this is any different of a pattern that a standard expression visitor, other than except for using a visitor type, it uses a function.
As for usage:
Expression<Func<int, int, int>> addLambdaExpression= (a, b) => a + b;
// Change add to subtract
Func<Expression, Expression> changeToSubtract = e =>
{
if (e is BinaryExpression)
{
return Expression.Subtract((e as BinaryExpression).Left,
(e as BinaryExpression).Right);
}
else
{
return e;
}
};
var nodes = new Expression[] { addLambdaExpression.Body }.ToList().AsReadOnly();
var subtractExpression = ExpressionVisitor.Visit(nodes, changeToSubtract);
You don't explain how you expected it to behave and why therefore you think it does little more than nothing.

How to get the position() of an XElement?

Any XPath like /NodeName/position() would give you the position of the Node w.r.t it's parent node.
There is no method on the XElement (Linq to XML) object that can get the position of the Element. Is there?
Actually NodesBeforeSelf().Count doesn't work because it gets everything even of type XText
Question was about XElement object.
So I figured it's
int position = obj.ElementsBeforeSelf().Count();
that should be used,
Thanks to Bryant for the direction.
You could use the NodesBeforeSelf method to do this:
XElement root = new XElement("root",
new XElement("one",
new XElement("oneA"),
new XElement("oneB")
),
new XElement("two"),
new XElement("three")
);
foreach (XElement x in root.Elements())
{
Console.WriteLine(x.Name);
Console.WriteLine(x.NodesBeforeSelf().Count());
}
Update: If you really just want a Position method, just add an extension method.
public static class ExMethods
{
public static int Position(this XNode node)
{
return node.NodesBeforeSelf().Count();
}
}
Now you can just call x.Position(). :)
Actually in the Load method of XDocument you can set a load option of SetLineInfo, you can then typecast XElements to IXMLLineInfo to get the line number.
you could do something like
var list = from xe in xmldoc.Descendants("SomeElem")
let info = (IXmlLineInfo)xe
select new
{
LineNum = info.LineNumber,
Element = xe
}
static int Position(this XNode node) {
var position = 0;
foreach(var n in node.Parent.Nodes()) {
if(n == node) {
return position;
}
position++;
}
return -1;
}

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