topic Re: Is it possible to completely move away from .NET to JavaScript? in ArcGIS JavaScript Maps SDK Questions

Is it possible to completely move away from .NET to JavaScript?

ChrisSergent — Fri, 26 Dec 2014 21:45:31 GMT

I am a .NET developer and I code web apps against databases. I have been able to move my GIS .NET development to the Esri JS API except for the proxy information, but is there a secure way to use JavaScript for interaction with just a database?

Ideally Esri will make the new data layer editable and that would take all limitations away as long as I could relate data geographically. That will take care of some, but probably not all. Any ideas? Or should I stick with .NET for talking to the server securely?

Thanks.

Re: Is it possible to completely move away from .NET to JavaScript?

PaulCrickard — Sun, 28 Dec 2014 00:00:41 GMT

Use .NET to write out some DB queries as JSON -I use MVC4. Then use AJAX on client side to grab the JSON and handle the parsing using a library linq.js.

Re: Is it possible to completely move away from .NET to JavaScript?

ChrisSergent — Tue, 30 Dec 2014 15:26:13 GMT

It's not looking like I can move away from .NET completely. Thanks for the input. I found it helpful.

Re: Is it possible to completely move away from .NET to JavaScript?

JoshHevenor — Tue, 30 Dec 2014 16:07:06 GMT

You can access your database through ArcGIS Server services. You're not personally writing SQL anymore but you're not using .NET anymore either.

As long as your website and arcgis server are on the same machine (or you're using the webadaptor) you might not need the proxy either.

Re: Is it possible to completely move away from .NET to JavaScript?

ChrisSergent — Tue, 30 Dec 2014 16:14:51 GMT

I'm not sure how I would write to a database outside of feature editing and some of my tables that I want to edit may not have GIS information in them.

Re: Is it possible to completely move away from .NET to JavaScript?

JohnHeinnickel — Sat, 10 Jan 2015 23:55:08 GMT

I wouldn't recommend accessing a database from client side JavaScript if the reason you're attempting to do so through a proxy is so you can have an encrypted channel between the browser and the client. Clientside Javascript is inherently vulnerable, so the encrypted channel is attempting to use a padlock to keep anyone from getting into a paper bag.

If someone wants to get at your database and can't get through the encyrpted channel,they'll just modify your code or inject their own by targetting the browser.

If you are hooked on the idea of a JavaScript-based access layer, I'd suggest using NodeJS server side. If you practice "safe selects" and do not trust any input you get from the client, you can retain control over what queries actually get invoked.

The malicious user who hacked your browser code and passed their own queries over the SQL channel would still be able to pass you their own crafted messages, but as long as you don't accept any input that would imply unsupported things happening, you are still safer this way because the database server cannot apply heuristics to discern safe from evil anywhere near as well as your own application code can.

Re: Is it possible to completely move away from .NET to JavaScript?

zhongrenGu — Sun, 11 Jan 2015 03:21:06 GMT

you can use arc SDE with you arcgis server to work,they can edit and save you data at the same times

Re: Is it possible to completely move away from .NET to JavaScript?

ChristophSpoerri — Sun, 11 Jan 2015 21:40:55 GMT

Hi Chris,

On the server side you may still need some .net, in order to provide the necessary DB and security interaction. I would propose you take a look at the Web API framework from Microsoft. It provides the necessary components to create a secure REST API, which you can then easily consume with a javascript client (we use angular js here ).

Cheers, Chris

Re: Is it possible to completely move away from .NET to JavaScript?

ChrisSergent — Mon, 12 Jan 2015 17:36:52 GMT

One question on that. Can the REST Services be published as editable?

Re: Is it possible to completely move away from .NET to JavaScript?

PaulCrickard — Mon, 12 Jan 2015 18:03:24 GMT

Sure can. If you set the feature to editable, all the properties can be edited. Can even add files/images. See my post on a ESRI REST API JavaScript class.

JavaScript Class for ESRI REST API | Architecture and Planning

Re: Is it possible to completely move away from .NET to JavaScript?

ChrisSergent — Mon, 12 Jan 2015 18:16:20 GMT

It looks like this is just for the Esri REST API. I have some non-spatial data in a DB2 database that I am trying to evaluate if it can be edited through web services. It looks like I would need to consume non-geospatial data through .NET web services.

Re: Is it possible to completely move away from .NET to JavaScript?

PaulCrickard — Mon, 12 Jan 2015 19:08:04 GMT

Try this tutorial for regular DB work.

Build RESTful API's with ASP.NET Web API | The ASP.NET Site

or this:

EF Database First with ASP.NET MVC: Creating the Web Application and Data Models | The ASP.NET Site

Re: Is it possible to completely move away from .NET to JavaScript?

ChrisSergent — Mon, 12 Jan 2015 20:32:50 GMT

Looks like I might need to learn AngularJS, ASP.NET MVC and maybe C#; still program in VB.NET. It looks like we could serve web services on the client using this though, but the rest services still need to be built with .NET. This provides me with a start. Time to start self-training.

Re: Is it possible to completely move away from .NET to JavaScript?

PaulCrickard — Mon, 12 Jan 2015 23:58:26 GMT

you can also use classic ASP to create a RESTish url. I just query a DB and spit out JSON manually. when you go to the URL for this script you get a JSON string that you can grab using AJAX in JavaScript from the client side.

set myconn_ = server.createobject("adodb.connection")

connection_ = "Provider=sqloledb; Data Source=xxxx; Initial Catalog=xxx;User Id=xxx; Password=xxx;Network Library=DBMSSOCN"

myconn_.open (connection_)

set result_ = server.createobject("adodb.recordset")

sql = "Select distinct Division, projectname, project_status, objectid from xxx.projects"

set result_ = myconn_.execute(sql)

Response.ContentType = "application/json"

response.write("[")

while not result_.EOF

response.write("{""division"":""" & result_("Division")&""",""objectid"":"""& result_("objectid") &""",""name"":"""& result_("ProjectName") &""",""pid"":"""& result_("Project_Status") &"""},")

result_.movenext()

wend

response.write(" {""division"":"" " & 9 &""",""objectid"":"""& 9 &" "",""name"":"""& 9 &" "",""status"":"""& 9 &"""}]")

result_.close

myconn_.close

set result_ = Nothing

set myconn_ = Nothing

response.end

Re: Is it possible to completely move away from .NET to JavaScript?

PaulCrickard — Tue, 13 Jan 2015 00:00:10 GMT

REST would have a url like someserver/product/1

or someserver/products/delete/5

The ASP solution requires a url like someserver/products.asp and someserver/products/delete.asp

Re: Is it possible to completely move away from .NET to JavaScript?

ChrisSergent — Tue, 13 Jan 2015 14:33:44 GMT

If it's ASP, I would rather use ASP.NET. I was just looking for a way to create regular HTML pages.

Re: Is it possible to completely move away from .NET to JavaScript?

DaveHighness1 — Thu, 22 Jan 2015 19:06:47 GMT

I've used Classic ASMX services with ScriptServices to create JSON and XML services to be consumed by AJAX web site with many different client side Javascript Libraries; Dojo, ExtJs, JQuery, etc. I like the classic ASMX services because they are fairly simple, to the point and easily customizable. You have full access to ASP.Net Security objects within the ASMX. I don't have a link to any website or blog with really good examples but if you Google you should find plenty of information.

I could slam together some example code if you desire.