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Dev Saturday UAE (Workflow SharepOint 2013)

Thanks to all MVPs, MCTs, Community Members ,for Participating in SharePoint Dev meetup.

https://sp2013devmeetup.eventbrite.com

 Allots of People ask Question’s on MSDN SharePoint 2013 forums. how they can host app on their public site. They want to use App Modules for Public facing site which have anonymous right or current user does not have permissions to. something like Elevate Privileges in developer`s term Elevate Privileges in App Module.  What i think Many developer start working API by small tutorials , sample code ,HOL and didn't understand what SharePoint 2013 New API is doing. new App Module is away with normally impersonation confusion and make it very clear for developers there is  no impersonation capability in the SharePoint 2013  API . so if  Elevate Privileges ,impersonation is not there how can  get thing to be done?. SO answer is the "App Only Policy".

The App Only Policy

In a Scenario App have to some work where current user does not have Permission. We will use “The App Only Policy”. When user did not provide any Kind of credential. An Oath access token is present but does not contain user information.  than we will evaluated the  permissions based App instead of user.

Authorization in SharePoint 2013 is divided in to two types of Entities.

 1st Permission for users.

2nd Permission for Apps.

App authorization policies types

 User-only policy—This user-only policy is the authorization policy that was always applied in SharePoint 2010. When the user-only policy is used, the authorization checks take into account only the user identity. An example of when this policy is enforced is when the user is accessing resources directly without using the app.

User + app policy—When the user + app policy is used, the authorization checks take into account both the user identity and the app identity. In particular, when this policy is used, authorization checks succeed only if both the current user and the app have sufficient permissions to perform the action in question.

An example of when this policy is used is when a SharePoint site has an embedded IFRAME that links to a Office Store app, and the app calls back to SharePoint to access SharePoint resources on behalf of the user. That is, when a Office Store app, which does not run in SharePoint Server, wants to act on behalf of the user to get access to the user's resources.

App-only policy—When the app-only policy is used, the content database authorization checks take into account only the app identity. In particular, when this policy is used, an authorization check succeeds only if the current app has sufficient permissions to perform the action in question, regardless of the permissions of the current user (if any).

Oath requires to generate App token. So App- Only Policy can only be used for  Auto Hosted Apps or  Provider Hosted Apps.  

SharePoint hosted Apps cannot use App-only policy.

To request  app to  use App-only policy  your app need to add attribute called “AllowAppOnlyPolicy”  in tag node of AppPermissionRequests with true value.             User Must be Site Collection Administrator for allow use of the app-only policy. 

On Code

Reference and Helpful Links

http://msdn.microsoft.com/en-us/library/fp142384.aspx

http://www.vrdmn.com/2013/01/sharepoint-2013-elevate-user-access.html

http://code.msdn.microsoft.com/office/SharePoint-2013-Make-app-6e3d1ee9

http://code.msdn.microsoft.com/office/SharePoint-2013-Make-app-6e3d1ee9

By Usama Wahab  Khan

To Create Call External Web Service in SharePoint 2013 App.  we need to WebProxy class to execute web Service Request in CSOM.  Let Create external Web service in SharePoint 2013  Sample App. remember SharePoint App Developer environment should configured.

How to: Set up an on-premises development environment for apps for SharePoint

How to: Set up an environment for developing apps for SharePoint on Office 365

You can also  use Office 365 SharePoint Online.

Open Visual Studio and Create SharePoint 2013 Project.

Add your Test or developer  Site URL

Open App.Js File from solution Explorer. Cope the Following from Sample code and Paste into App.js

To Call External URL from App you need to set Permission for that URL in you App Manifest

Add your External Web Service  URL in Side tag in my case i am using free online sample of northwind Database which avaliable on services.odata.org domain name.

Open your default.aspx file in App and SP.runtime.js  and Also Executed SharePOint Ready method  

Define html Container with ID in my case i used message in js code so i defined tab with id

 and Hit F5

Download code Link :http://code.msdn.microsoft.com/SharePoint-Call-External-83b49a85

Related Content

• SP.WebProxy object
• Work with data in SharePoint 2013
• Apps for SharePoint overview
• Hosting options for apps for SharePoint
• Build apps for SharePoint
• How to: Create a basic SharePoint-hosted app (A Must)

 By usama wahab khan

Thanks to Microsoft Certified Trainer Team for Welcome MCT Welcome kit.

Javascript :)  

   // ---------- Start workflow ---------- 
    function StartWorkflow() { 
      var errorMessage = "An error occured when starting the workflow."; 
      var subscriptionId = "", itemId = "", redirectUrl = ""; 
 
      var urlParams = GetUrlParams(); 
      if (urlParams) { 
        //itemGuid = urlParams["ItemGuid"]; 
        itemId = urlParams["ID"]; 
        redirectUrl = urlParams["Source"]; 
        subscriptionId = urlParams["TemplateID"]; 
      } 
 
      if (subscriptionId == null || subscriptionId == "") { 
        // Cannot load the workflow subscription without a subscriptionId, so workflow cannot be started. 
        alert(errorMessage + "  Could not find the workflow subscription id."); 
        RedirFromInitForm(redirectUrl); 
      } 
      else { 
        // Set workflow in-arguments/initiation parameters 
        var wfParams = new Object(); 
 
        // get reviewer loginname 
        var html = $("#ctl00_PlaceHolderMain_docReviewerUser_upLevelDiv"); 
        wfParams['DocReviewerLoginName'] = $("#divEntityData", html).attr("key"); 
        // get editor loginname 
        var html = $("#ctl00_PlaceHolderMain_docEditorUser_upLevelDiv"); 
        wfParams['DocEditorLoginName'] = $("#divEntityData", html).attr("key"); 
 
        // Get workflow subscription and then start the workflow 
        var context = SP.ClientContext.get_current(); 
        var wfManager = SP.WorkflowServices.WorkflowServicesManager.newObject(context, context.get_web()); 
        var wfDeployService = wfManager.getWorkflowDeploymentService(); 
        var subscriptionService = wfManager.getWorkflowSubscriptionService(); 
 
        context.load(subscriptionService); 
        context.executeQueryAsync( 
 
            function (sender, args) { // Success 
              var subscription = null; 
              // Load the workflow subscription 
              if (subscriptionId) 
                subscription = subscriptionService.getSubscription(subscriptionId); 
              if (subscription) { 
                if (itemId != null && itemId != "") { 
                  // Start list workflow 
                  wfManager.getWorkflowInstanceService().startWorkflowOnListItem(subscription, itemId, wfParams); 
                } 
                else { 
                  // Start site workflow 
                  wfManager.getWorkflowInstanceService().startWorkflow(subscription, wfParams); 
                } 
                context.executeQueryAsync( 
                    function (sender, args) { 
                      // Success 
                      RedirFromInitForm(redirectUrl); 
                    }, 
                    function (sender, args) { 
                      // Error 
                      alert(errorMessage + "  " + args.get_message()); 
                      RedirFromInitForm(redirectUrl); 
                    } 
                ) 
              } 
              else { 
                // Failed to load the workflow subscription, so workflow cannot be started. 
                alert(errorMessage + "  Could not load the workflow subscription."); 
                RedirFromInitForm(redirectUrl); 
              } 
            }, 
            function (sender, args) { // Error 
              alert(errorMessage + "  " + args.get_message()); 
              RedirFromInitForm(redirectUrl); 
            } 
        ) 
      } 
    } 
 
    // ---------- Redirect from page ---------- 
    function RedirFromInitForm(redirectUrl) { 
      window.location = redirectUrl; 
    } 
 
    // ---------- Returns an associative array (object) of URL params ---------- 
    function GetUrlParams() { 
      var urlParams = null; 
      if (urlParams == null) { 
        urlParams = {}; 
        var parts = window.location.href.replace(/[?&]+([^=&]+)=([^&]*)/gi, function (m, key, value) { 
          urlParams[key] = decodeURIComponent(value); 
        }); 
      } 
      return urlParams; 
    } 

C#

var WSM = new WorkflowServicesManager(web);
var wfSubscriptionService = WSM .GetWorkflowSubscriptionService();
//get all workflows associated with the list
var subscriptions =  wfSubscriptionService .EnumerateSubscriptionsByList(listId);
//run all workflows associated with the list
foreach (var workflowSubscription in subscriptions)
{    
   //initiation parameters    
   var inputParameters = new Dictionary();    
   inputParameters.Add("WFProperty", "Value"); 
   WSM .GetWorkflowInstanceService().StartWorkflowOnListItem(workflowSubscription, itemId, inputParameters);
}

Start: Set up and configure SharePoint 2013 Workflow Manager

Reference :

http://code.msdn.microsoft.com/office/SharePoint-2013-Approval-f5ac5eb2