ServiceStack TimeSpan Serialization can't be Cast by SQL to Time(7) - c#

When TimeSpan properties are serialized they end up looking like this: -PT10M, PT30S, or PT6H. My real problem is that in MSSQL I can't use the Cast function to get them to a Time so if there's an easy way to do that I'm open to that solution however I believe the easiest thing will be to figure out how to get ServiceStack to change it's serialization behavior and instead serialize them like this -0:10:00, 0:00:30, or 6:00:00 respectively.
The way I'm serializing them now is to just call MyObject.ToJson().
Is changing the serialization the way to go and if so how can I do that with ServiceStack?
UPDATE
Please ignore the negative time values I'm aware SQL's Time type can only hold positive values. This actually doesn't affect what I'm trying to do at the moment. I have other fields where the time can sometimes be negative so I included them in my question as an example but it's not really relevent to my question.
After some more testing I can confirm that values stored like this like this -0:10:00, 0:00:30, or 6:00:00 deserialize fine. Still, is there a way to force them to serialize to this more easily readable value like this?
Here's almost the same question for Newtonsoft: https://stackoverflow.com/questions/39876232

Related

WorkFront / AtTask API $$TODAYe+6m flaw?

The workfront API isn't returning the same results as our web report:
On our web front-end on workfront one of the reports has a date range from $$TODAYbw to $$TODAYe+6m and it returned about ~500 rows.
I tried the same query on the API like so (formatted for easier reading)
/v7.0/RSALLO/search
?fields=DE:project:Probability,allocationDate,scheduledHours,project:name,project:status,roleID,project:status,role:name
&allocationDate_Mod=between
&allocationDate=$$TODAYbw
&allocationDate_Range=$$TODAYe+6m
&AND:0:project:status_Mod=notin
&AND:0:project:status=CPL
&AND:0:project:status=DED
&AND:0:project:status=REJ
&AND:0:project:status=UZF
&AND:0:project:status=IDA
&AND:0:roleID_Mod=in
&AND:0:roleID=55cb58b8001cc9bc1bd9767e080f6c10
&AND:0:roleID=55cb58b8001cc9bd9fc0f8b03a581493
&AND:0:roleID=55cb58b8001cc9bfaa01243cd6024b6d
&AND:0:roleID=55cb58b8001cc9c0afa399dece405efd
&$$LIMIT=1000
which returned barely any results. Notice the &allocationDate_Range=$$TODAYe+6m line. If I change it to read =$$TODAY+6m without the end of day modifier the API returns ~500 rows.
I went through every filter criteria and it's only the allocationDate range that is going wrong. I found this resource for the date modifiers and in it there is no e+6m example, yet it works on our web front-end report.
Is the API flawed or is the web report doing something extra in the background?
I don't have an exact solution for your problem, but I can confirm that the API does have some difficulty parsing wildcards like you're trying to use and they don't always come up the way we expect. Furthermore, the API doesn't parse things the same way as text mode reporting, so a query that looks great in the latter might return something different in the former.
If I may propose a different solution, since you're already coding this up outside of Workfront then I suggest you simply perform the date calculations on your own and pass explicit datetime objects to Workfront instead of allowing it to use its own logic. I know this doesn't answer the question of "what is a query that will return exactly what I want" but it should give you the correct end result.
For what it's worth, I spent about 15 minutes trying to get an example working on my end and I gave up after it kept returning values which should have been outside of my own date range.

Json.net, deserialize dates out of range

I'm having trouble deserializing dates with Newtonsoft.Json.
I have a class in C#, and complex data types in postgresql. With the row_to_json function of postgresql I have lot of the work done retriving data from database.
Everything works fine, then, when I have an infinity date, I got this error:
{"Could not convert string to DateTime: -infinity. Path 'valid_from', line 1, position 101."}
The code line I use is:
JsonConvert.PopulateObject(l[icont], myclass);
Where l is a list of json strings, icont is a counter and myclass is an instance of my class.
The closest documentation I found to my problem is here, where this problem is considered a bug: https://bugzilla.xamarin.com/show_bug.cgi?id=22955
I have few workarounds in mind:
Use strings for dates in my c# class. I don't like this :-/
Force the postgresql function to return special dates, like 01/01/1800 and 01/01/2200 and manage them. This can be OK because it is not storical data, but it is not... elegant.
How can I workaround this and keep infinity values in db?

How can I create or set JodaTime DateTime objects with/to maximum value?

I am translating some C#-code to Java, and have chosen JodaTime's DateTime class, to replace C#'s System.DateTime.
In C# the DateTime class has a Field called MaxValue and one called MinValue, which returns the biggest and smallest possible value that the DateTime object can hold.
I am trying to achieve the same with the JodaTime api. I have read some suggestions on other posts
This one: Java equivalent of .NET DateTime.MinValue, DateTime.Today answers how to make today's date in JodaTime, but when answering the second half of the question, about Min Values, they turn to Calendar and Date
Likewise I have seen suggestions about passing a maximized long value as constructor parameter, but it was criticized for being dependant on classes that might be changed in the future, and therefor might not be compatible or accurat after API updates.
So, is there a single positively correct way to do this? If not, is there a good way to achieve this?
Java 8 LocalDate has two values. LocalDate.MAX and LocalDate.MIN
LocalDate.MAX - The maximum supported LocalDate, '+999999999-12-31'. This could be used by an application as a "far future" date.
LocalDate.MIN - The minimum supported LocalDate, '-999999999-01-01'. This could be used by an application as a "far past" date.
Note: these do not translate to Long.MIN_VALUE or Long.MAX_VALUE.
I suggest using Java 8 if migrating from C# and how date/time works is important to you, as it has closures AND a new DateTime API based on JodaTime. This new DateTime API is the one you should be using if you are worried about the future of an API.
I think you can assume that Long.MIN_VALUE and Long.MAX_VALUE will never change as they are based on the definition of how a signed 64-bit values work. (How 64-bit values work was standardised before you were born, most likely) You can also assume that Date will not change as it hasn't change much since it was released and since it has been replaced there is even less reason to change it. In theory it might be deprecated, but in reality there is still too much code which uses it.
IMHO, I use long to represent a time in milli-seconds ala System.currentTimeMillis() and I use Long.MIN_VALUE and Long.MAX_VALUE.
If you are concerned about using good API and future proofing your code, I suggest you avoid using Calendar. Not that it is all bad, but there are good reasons to want to replace it.

C#: Dateformat in C# for Inserting to sql server

I have a textbox with date format dd/MM/yyyy that I want to convert to the format yyyy-MM-dd to insert it into a database.
I tried
Convert.DateTime/DateTime.ParseExact
but it always give me the system's default date format.
I don't know any other method to convert it in C#...
You shouldn't be converting it to a string at all to insert it into your database. (I'm surprised at all the other answers which are recommending this approach.)
Instead, you should be using parameterized SQL, and set the value of the parameter to the DateTime value you've got. You should be using parameterized SQL anyway to avoid SQL injection attacks, and to keep your code and data separate. The fact that it avoids unnecessary string conversions (each of which is a potential pain point) is yet another benefit.
This part of your question suggests you've got a fundamental misconception:
I used Convert.DateTime/DateTime.ParseExact it always give me system date format.
Those methods will give you a DateTime. A DateTime doesn't have a format. When you call ToString you just get the default format for the current culture, but that's not part of the value. It's like with numbers - 16 and 0x10 are the same number, and the int doesn't "know" whether it's in decimal or hex; it's a meaningless concept.
All of this goes beyond your immediate problem, towards trying to keep your code base clean in terms of types. You should keep data in its most appropriate form for as much of the time as you possibly can, and make sure you understand exactly what that data means at all points. Conversions to other types (such as strings) for communication should be done only at API/system boundaries, and avoided even there if possible (e.g. using parameterized SQL as in this case).
There are many methods but none so useful and logical than using Parametrized SQL. Here's the Wikipedia page! For more information on Parametrized SQL statements, Visit this Coding Horror page!
There is actually no need to change it. This is just the display format, but the 'DateTime' object inside stays the same. Depending on how you want to insert, you can just use:
string dateValue = DateTime.Now.ToString("yyyy-MM-dd");
And insert this in your query string.
EDIT
But as Jon Skeet commented, building your query string manually like this should never be done. A cleaner approach like parameterized SQL or utilizing NHibernate should be your first concern.
Hope this works!
DateTime variable= Convert.ToDateTime(your date);
You can format it like this:
string sDateTime = Convert.ToDateTime(txtTextBox.Text).ToString("yyyy-MM-dd");
Edit
There are many ways to skin a cat when it comes to preparing information for entry into a database. My solution here answers the OP directly, however I very much acknowledge that there are better ways to do this.
I'd suggest reading through Jon Skeet's post on this page as well, as he raises some extremely valid points regarding the approach of the OP.
Hope that helps.

c#: tryparse vs convert

Today I read an article where it's written that we should always use TryParse(string, out MMM) for conversion rather than Convert.ToMMM().
I agree with article but after that I got stuck in one scenario.
When there will always be some valid value for the string and hence we can also use Convert.ToMMM() because we don't get any exception from Convert.ToMMM().
What I would like to know here is: Is there any performance impact when we use TryParse because when I know that the out parameter is always going to be valid then we can use Convert.ToMMM() rather TryParse(string, out MMM).
What do you think?
If you know the value can be converted, just use Parse(). If you 'know' that it can be converted, and it can't, then an exception being thrown is a good thing.
EDIT: Note, this is in comparison to using TryParse or Convert without error checking. If you use either of the other methods with proper error checking then the point is moot. I'm just worried about your assumption that you know the value can be converted. If you want to skip the error checking, use Parse and die immediately on failure rather than possibly continuing and corrupting data.
When the input to TryParse/Convert.ToXXX comes from user input, I'd always use TryParse. In case of database values, I'd check why you get strings from the database (maybe bad design?). If string values can be entered in the database columns, I'd also use TryParse as you can never be sure that nobody modifies data manually.
EDIT
Reading Matthew's reply: If you are unsure and would wrap the conversion in a try-catch-block anyway, you might consider using TryParse as it is said to be way faster than doing a try-catch in that case.
There is significant difference regarding the developing approach you use.
Convert: Converting one "primitive" data in to another type and corresponding format using multiple options
Case and point - converting an integer number in to its bit by bit representation. Or hexadecimal number (as string) in to integer, etc...
Error Messages : Conversion Specific Error Message - for problems in multiple cases and at multiple stages of the conversion process.
TryParse: Error-less transfer from one data format to another. Enabling T/F control of possible or not.
Error Messages: NONE
NB: Even after passing the data in to a variable - the data passed is the default of the type we try to parse in to.
Parse: in essence taking some data in one format and transfer it in to another. No representations and nothing fancy.
Error Messages: Format-oriented
P.S. Correct me if I missed something or did not explain it well enough.

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