Project PSI reference overview

The Project Server Interface (PSI) is the API to use for developing applications that integrate with Project Server 2013 on-premises. This article is an overview of the documented assemblies, namespaces, and services in the PSI. The Project Server 2013 class library and web service reference in the SDK contains all of the managed code documentation for the PSI and the Microsoft.ProjectServer.Client namespace in Project Server 2013. To develop applications for Project Online, you must use the Microsoft.ProjectServer.Client namespace instead of the PSI.

The PSI in Project Server 2013 has a dual interface. The ASMX interface for web services is defined by discovery and Web Service Description Language (disco and WSDL) files in the https://ServerName/ProjectServerName/_vti_bin/psi/ virtual directory (for example, Projectdisco.aspx and Projectwsdl.aspx). You can access the ASMX interface only through the URL of an on-premises installation of Project Web App (for example, https://ServerName/ProjectServerName/_vti_bin/psi/project.asmx?wsdl). To show the web service in a browser, you must include the ?wsdl URL option. Because the ASMX interface is built using the Windows Communication Foundation (WCF) infrastructure, the .asmx files for Project Server web services do not actually exist in the virtual PSI directory.

The WCF services interface is defined by .svc files in the back-end https://ServerName:32843/GUID/PSI/ virtual directory in the SharePoint Web Services application. The URL of PSI services in the Project Service Application virtual directory (for example, https://ServerName:32843/GUID/PSI/project.svc) includes the .svc files. But, you cannot directly use the back-end URL to set a WCF service reference. To develop an application or component that uses the WCF services of the PSI, you can use a proxy assembly or a proxy file. The Project 2013 SDK download includes proxy files for the WCF services in Project Server 2013, and scripts to get updated WCF proxy files and to compile the files into a proxy assembly for more recent Project Server builds.

The Project Service Application directory name is a GUID value, which is the same as the GUID of the on-premises Project Web App instance. In the Internet Information Services (IIS) Manager window, expand the SharePoint Web Services node, choose the GUID directory name, and then choose Advanced Settings to copy the Virtual Path value.


The ASMX web service interface of the PSI is deprecated in Project Server 2013, but is still supported. New applications should use the WCF interface of the PSI or the CSOM. For more information about deprecated features, see Updates for developers in Project 2013.

New applications, and middleware components that run only on an on-premises installation of Project Server, should use the WCF interface, which is the technology that we recommend for network communications. Legacy applications that use the ASMX interface must use the URL through Project Web App, which checks Project Server permissions.

For more information about the ASMX interface and how to use the WCF interface, see Prerequisites for ASMX-based code samples in Project and Prerequisites for WCF-based code samples in Project.

For developing applications that use the WCF interface, you can use Visual Studio 2010 or Visual Studio 2012. For creating declarative Project Server workflows, you can use SharePoint Designer 2013. Project Server workflows that require access to the PSI or the CSOM can be developed with Visual Studio 2012.

Use the PSI reference

The PSI object model is large, and many classes and members are for internal use only. As a result, it can be confusing to find the topics that you want in the Project Server 2013 class library and web service reference. Most of the reference topics that you will use for development are in the following groups:

  • Primary class methods: Each service in the PSI includes a primary class that is named for the name of the service. For example, the Resource service contains the Resource class, which is in the WebSvcResource namespace. To see a list of the methods that are available in the Resource class, expand the class node in the content pane, and then choose the Resource Methods topic.
  • DataRow properties: Many of the primary class methods use or return a DataSet. Each DataTable object in a DataSet contains data in one or more DataRow objects. In most cases, you need to see only the row properties, not all of the other members of the DataSet, DataTable, or DataRow classes. For example, the ResourceAssignmentDataSet class includes subclasses for the ResourceAssignmentDataTable and the ResourceAssignmentDataSet.ResourceAssignmentRow class. To see a list of properties that are in the ResourceAssignmentRow class, expand the class node in the content pane, and then choose the ResourceAssignmentDataSet.ResourceAssignmentRow Properties topic.

In addition to the service namespaces, the Project Server 2013 class library and web service reference topic links to the three Project Server assemblies that are used in development of third-party solutions for on-premises installations. We provide only minimal documentation for these assemblies. The PSI reference documents the main classes and members in the 23 public services. Six PSI services are for internal use only, and are not documented.


Classes in the client-side object model (CSOM) can be used independently from the other Project Server assemblies and services. You can use the Microsoft.ProjectServer.Client namespace in a remote development environment from the Project Server computer, and develop apps that integrate with Project Online or with an on-premises installation of Project Server. But, the CSOM contains a subset of the functionality of the complete PSI. The CSOM enables development of the most common scenarios for Project Server integration. For more information, see What the CSOM does and does not do and Microsoft.ProjectServer.Client.

For development of most applications that use the PSI, you do not have to develop on a Project Server computer, or set references to Project Server assemblies in the global assembly cache. You can copy the necessary Project Server assemblies to your development computer. Project Server 2013 installs the following assemblies in [Program Files] \Microsoft Office Servers\15.0\Bin:

  • Microsoft.Office.Project.Server.Events.Receivers.dll
  • Microsoft.Office.Project.Server.Library.dll
  • Microsoft.Office.Project.Server.Workflow.dll

Namespaces for the PSI services have arbitrary names created for a PSI proxy assembly, ProjectServerServices.dll, which is generated for the purpose of documentation. In the PSI reference, each service namespace has a placeholder name (such as [Project web service]) and a web reference (such as https://ServerName/ProjectServerName/_vti_bin/psi/Project.asmx?wsdl).

Project Server assemblies and namespaces

Many assemblies are installed when you install Project Server; only four of the Project Server assemblies are documented. Third-party developers generally use only a few classes and members in those assemblies. The undocumented Project Server assemblies include namespaces and classes that Project Server uses internally, such as classes for Project Web App, the business entities, and the data access layer (DAL). When you set a reference in Visual Studio to one of the documented Project Server assemblies, you can see all of the namespaces, classes, and members in the Visual Studio Object Browser.


Many members of the documented Project Server namespaces are used only internally and have minimal documentation.

When developing for Project Online, you can use only the CSOM to access Project Server functionality. You do not have access to the PSI services or the other Project Server assemblies.

The Project Server 2013 class library and web service reference for the PSI includes namespaces from the following assemblies:

  • Microsoft.Office.Project.Server.Library.dll This assembly contains one documented namespace and three undocumented namespaces, as follows:

  • The Microsoft.Office.Project.Server.Library namespace includes many enumerations, and class fields and properties that are frequently used in on-premises applications for Project Server. For example, developers typically use enumerations such as CustomField.Type, and the PSClientError, PSErrorInfo, and Filter classes.

The Microsoft.Office.Project.Server.Library namespace also includes the following seven property classes, which include over 3,200 subclasses:

  • AssignmentProperties
  • CalendarProperties
  • ConstraintProperties
  • LookupTableProperties
  • ProjectProperties
  • ResourceProperties
  • TaskProperties

The property classes are used internally and are not documented. The property classes are used for serialization between Project Professional 2013 and Project Server. When you work with the Microsoft.Office.Project.Server.Library namespace in Visual Studio, the Object Browser shows all of the property classes, which makes it more difficult to find classes that are useful for third-party development. Because third-party developers do not have to use the property classes, the SDK does not document them.

  • Microsoft.Office.Project.Server.DataServices The classes and members of this namespace are used internally by the OData service in Project Online for access to the reporting tables in the Project database. The DataServices classes are not documented.

  • Microsoft.Office.Project.Server.Administration The class and members of this namespace are used internally for diagnostic logging, and are not documented.

  • Microsoft.Office.Project.Server.Base The classes and members of this namespace are used internally as base classes and are not documented.

  • Microsoft.Office.Project.Server.Library.FilterSchema This namespace is used internally to generate filter schemas and is not documented.

  • Microsoft.Office.Project.Server.Workflow.dll This assembly is used for legacy Project Server 2010 workflows that can still work in Project Server 2013. For creating new workflows, you should use SharePoint Designer 2013, or you can also use Visual Studio 2012 with the Microsoft.ProjectServer.Client.WorkflowActivities class. The Microsoft.Office.Project.Server.Workflow.dll assembly includes the following three namespaces:

  • Microsoft.Office.Project.Server.Workflow This namespace includes classes that are used for Project Server workflow activities. Activities include reading, comparing, and updating project properties. Other classes manage workflows and include workflow call-backs when projects are changed.

  • Microsoft.Office.Project.PWA This namespace includes an internal proxy for the PSI, for use with Project Web App and with custom workflow activities; it is not documented.

    A custom workflow activity requires a reference to Microsoft.Office.Project.PWA to access all of the classes in the PSI services. For example, the Microsoft.Office.Project.PWA.PSI class includes the ProjectWebService property, which gets a proxy for the WebSvcProject namespace.

  • Microsoft.Office.Project.Server.WebServiceProxy This namespace includes internal proxy classes for the primary class in each PSI service. By using the elevated permissions of the workflow user, the workflow can call PSI methods through proxy classes. The proxy classes are not documented.

  • Microsoft.Office.Project.Server.Events.Receivers.dllMicrosoft.Office.Project.Server.Events is the only namespace in this assembly. It includes event receiver and event argument classes for the PSI services and other internal classes.

Developers write event handlers that derive from event receiver classes. Most of the primary classes in the PSI services have a corresponding event receiver class. For example, the ProjectEventReceiver class contains pre-event and post-event receiver methods that correspond to methods in the Project class in the PSI. The OnCreating method and the OnCreated method are the pre-event and post-event receiver methods for the QueueCreateProject method.

Developers typically use the following event receiver classes:

The RulesEventReceiver class and the StatusReportsEventReceiver class are used internally in Project Web App.

  • Microsoft.ProjectServer.Client.dll This assembly contains the CSOM for development with the .NET Framework 4. The assembly is located in %ProgramFiles%\Common Files\Microsoft Shared\Web Server Extensions\15\ISAPI\Microsoft.ProjectServer.Client.dll. Development of apps with the Microsoft.ProjectServer.Client namespace is independent of the on-premises Project Server APIs and services, although the apps can work with either an on-premises or online installation of Project Server. For related CSOM assemblies that can be used for Windows Phone 8, Microsoft Silverlight, or JavaScript with web apps, see Microsoft.ProjectServer.Client.

  • Microsoft.Office.Project.Server.Schema.dll The Project 2013 SDK does not document the Microsoft.Office.Project.Server.Schema namespace, which is in the [Windows]\Microsoft.NET\assembly\GAC_MSIL\Microsoft.Office.Project.Schema\v4.0_15.0.0.0__71e9bce111e9429c\Microsoft.Office.Project.Schema.dll assembly. The namespace contains the definitions of all DataSet, DataTable, and DataRow classes used in the PSI, plus many other similar classes that Project Server uses internally. The public classes in each PSI service are documented in the specific service reference. For example, the DriverDataSet.DriverRow class is documented in the WebSvcDriver namespace.


Applications that use the CSOM, use remote event handlers, or access Project Online do not use the Microsoft.Office.Project.Server.Schema namespace.

In some applications that use full-trust event handlers, where the event handlers are installed on the Project Server computer, it is necessary to set a reference to the Microsoft.Office.Project.Schema.dll assembly. Following are two examples:

  • In a full-trust OnCreated post-event handler for custom fields, you can use the e.CustomFieldInformation event argument with a reference to the Microsoft.Office.Project.Server.Schema namespace for the CustomFieldDataSet and CustomFieldsRow definitions.
  using PSLibrary = Microsoft.Office.Project.Server.Library;
  using Microsoft.Office.Project.Server.Schema;
  . . .
  // Event handler for the OnCreated event of a custom field.
  public override void OnCreated(
      PSLibrary.PSContextInfo contextInfo, 
      CustomFieldsPostEventArgs e)
      // Get information from the event arguments. 
      string userName = contextInfo.UserName.ToString();
      CustomFieldDataSet customFieldDs = e.CustomFieldInformation;
      CustomFieldsRow customFieldRow = customFieldDs.CustomFields.Rows[0];
      string customFieldName = customFieldRow["MD_PROP_NAME"].ToString();
      byte customFieldType = (byte)customFieldRow["MD_PROP_TYPE_ENUM"];
      Guid customFieldUid = (Guid)customFieldRow["MD_PROP_UID"];
      . . .
  • A custom workflow activity can require a reference to Microsoft.Office.Project.Server.Schema for DataSet definitions.

PSI services

The PSI is a set of WCF services and identical ASMX web services for Project Server 2013. To use a service in a Visual Studio project, you set a reference to the URL of the .svc file or the .asmx?wsdl service by using an arbitrary name for the nameservice. The wsdl.exe utility or the svcutil.exe utility then generates proxy source code for that namespace, and the compiler creates a proxy service assembly to include in your application.


The PSI reference includes placeholder nameservice names for the PSI services such as [Admin web service], [Driver web service], and [Project web service]. Each PSI nameservice includes a primary class that contains the web methods for that service. For example, if you set a reference to the Admin service and name it WebSvcAdmin, then in your application the WebSvcAdmin nameservice includes the primary Admin class that has the web methods GetServerCurrency, ListInstalledLanguages, ReadServerVersion, and so on. See Updates for developers in Project 2013 for a list of deprecated PSI services.

Of the 30 total PSI services, authentication, ExchangeSync, OData, P12Upgrade, psiserviceapp, PWA, View, and WinProj are for internal use by Project Web App and Project Professional and are not documented. Although you can create proxy files or a proxy assembly that includes the PSI internal services, the internal services are not for third-party use; the PSI reference does not document those services. The following figure shows the location of the back-end PSI services in Internet Information Services Manager.

Locate the PSI services in IIS

PSI services in IIS Manager

The following are all of the classes that contain web methods in the PSI services:

  • Admin Includes methods that are used in the Project Server Administration pages in Project Web App. Defines fiscal years, manages statusing and currency settings, reporting periods, the audit log, and settings for Active Directory.
  • Archive Includes methods for managing backup and restoration of projects, security categories, custom fields, resources, system settings, views, and the enterprise global project. Reads and updates the archive schedule. Archives all projects or deletes specified archived projects. Saves backup objects to the Archive database tables and restores backed up objects to the Published database tables.
  • authentication Includes methods for internal use only by Project Professional and Project Web App.
  • Calendar Manages enterprise calendar exceptions. Checks out and checks in resource calendars. Creates, deletes, lists all, updates, or returns calendar exceptions.
  • CubeAdmin Manages OLAP cube settings. Gets Analysis Server, database status, and list of cubes. Puts a Cube Build Service request on the queue. Reads and updates calculated member definitions and field settings for dimensions and measures in the cube.
  • CustomFields Manages enterprise custom fields. Includes the check out and check in methods, and the create, read, update, and delete (CRUD) methods for enterprise custom fields.
  • Driver Manages portfolio analysis drivers and driver prioritization for project creation and Demand Management. Includes the CRUD methods for project drivers.
  • Events Manages Project Server event handler associations. Includes the CRUD methods for Project Server event handler associations for a specific event, or for all event handler associations.
  • ExchangeSync This is an internal Project Server service that handles Exchange Server events. Project Web App uses ExchangeSync to synchronize assignments between Project Server and Exchange Server, instead of synchronizing directly with the Outlook client as in Office Project Server 2007. Access to the ExchangeSync service is available only through the ProjectServiceApplication URL. The ExchangeSync classes and members are not supported for third-party development.
  • LoginForms Provides the Login and Logoff methods with Forms-based authentication. Access to the LoginForms service is available only on a front-end Project Web App site.
  • LoginWindows Provides the Login and Logoff methods that are used for Windows authentication with ASMX-based applications for multiple authentication (claims and Forms-based) Project Server 2013 installations. Access to the LoginWindows service is available only on a front-end Project Web App site.


The LoginWindows service is not used in WCF-based applications, or for applications that run on Project Server installations that use only claims authentication or OAuth; in those cases, the Login method always returns false. Claims authentication handles integrated Windows authentication.

  • LookupTable Manages lookup tables, multilanguage lookup tables, and their corresponding code masks. Checks out, checks in, reads, creates, deletes, and updates.

  • Notifications Manages alerts and reminders. Includes methods that get, set, register, and unregister alert results.

  • ObjectLinkProvider Manages web objects and links for documents and list items on SharePoint sites. Creates, deletes, or reads project, project-linked, task, or task-linked web objects.


    The ObjectLinkProvider service is deprecated in Project Server 2013. For more information, see the Deprecated features section in Updates for developers in Project 2013.

  • OData Provides the internal OData interface for the reporting tables and views. Access to the OData service is available only through the back-end ProjectServiceApplication URL. The private OData service in the PSI provides one method, ODataClient.ProcessOdataMessage, which Project Server uses internally to process requests for reporting data. The HTTP requests go through the front-end ProjectData service. For information about the ProjectData service and the OData protocol to read reporting data, see ProjectData - Project OData service reference.

  • P12Upgrade Provides internal methods for the Project Server 2013 installer to upgrade an Office Project Server 2007 installation. Access to the P12Upgrade service is available only through the ProjectServiceApplication URL. The P12Upgrade methods are not supported for third-party development.

  • PortfolioAnalyses Includes the CRUD methods for project dependencies, and for Optimizer, Planner, and Analysis solutions.

  • Project Manages projects. Checks out, checks in, creates, deletes, reads, or updates projects in the Project database draft tables or published tables. Puts a message on the queue for publishing.

    • Creates or deletes entities within projects (tasks, resources, assignments, and so on). Gets information about or updates the project team or project site address. Gets project status, a list of projects in the draft tables, all summary tasks, tasks that are available for assignment to a specified resource, or all projects where a resource has assignments.
    • Creates and manages commitments, creates project proposals and projects from SharePoint task lists, and finds project/master project relationships.
  • psiserviceapp Used internally by Project Online. The psiserviceapp classes and members are not supported for third-party development.

  • PWA Contains many methods that are optimized for Project Web App, including the methods for task update approval rules and for managing status reports. The PWA methods are often specialized and somewhat redundant compared to equivalent methods in other PSI services. PWA methods use or return many of the same datasets as the other PSI methods. Access to the PWA service is available only through the ProjectServiceApplication URL. The PWA classes and members are not supported for third-party development.

  • QueueSystem Manages the Project Server queue. Gets job count, job and job group wait time, status of all jobs, specified jobs, jobs owned by the caller, or jobs for specified projects. Manages job correlation and configures the queue.

  • Resource Manages enterprise resources. Checks out, checks in, updates, or creates resources or Project Server users and their authorization settings; finds resources by name or GUID; reads resource or user data and the resource breakdown structure (RBS) and related security information; gets all assignments for a resource; and resets user passwords. The Resource class includes CRUD methods for user delegations.

  • ResourcePlan Manages resource plans. Checks out, checks in, publishes, and includes the CRUD methods for resource plans.

  • Security Includes the CRUD methods for security templates, security categories, organizational and global permissions, and group permissions. The Security class includes methods for project categories.

  • Statusing Manages status updates and assignments. Applies status updates or approvals, submits status updates, sets summary information for submitted updates, deletes approved status updates or approval history for a specified user, or deletes all status information for a set of projects. Creates, gets, or delegates assignments; sets assignment work duration. Gets new assignments for the current user; gets assignment or task transaction history, the timephased actuals, or the summary task hierarchy. Previews or imports timesheet data, or reads a user's working and nonworking schedule. Finds pending status updates, information for submitted updates, or a transaction record of changes in a submitted update. Reads team status.

  • TimeSheet Manages timesheets. Includes the CRUD methods for timesheets, and submits or recalls timesheets. Finds timesheets that are late or pending approval; finds timesheets by date or period. Gets list of timesheet approvers. Preloads timesheet actuals and validates a timesheet line. The TimeSheet class includes the ReadProjectTimesheetLines method and the SubmitTimesheetLines method for reading and submitting timesheets for another resource without requiring impersonation.

    • View The View service is designed for use only within Project Web App. Methods in the View class manage views and view reports and read fields in views. Access to the View service is available only through the ProjectServiceApplication URL. The View methods are not supported for third-party development.
    • WinProj The WinProj service is designed for use only by Project Professional. Third-party developers should not use WinProj methods for programming with Project Server.
      • Some WinProj methods use datasets such as ProjectRelationsDataSet and ResourceDataSet that the Project and Resource services also use, but require specific properties and functions in Project Professional.
      • Access to the WinProj service is available only through the ProjectServiceApplication URL. The WinProj methods are not supported for third-party development.
  • Workflow Includes the CRUD methods for enterprise project types and for managing workflow phases and stages. Runs workflows, sets status information, and manages project detail page (PDP) stages in demand-management workflows. To develop Project Server workflows, developers can use SharePoint Designer 2013 for declarative workflows or use the Office Developer Tools for Visual Studio 2012 for development with .NET Framework 4 and the Microsoft.ProjectServer.Client.WorkflowActivities class in the CSOM.

  • WssInterop Manages project sites. Creates and deletes project sites. Gets information about and updates SharePoint settings and administration sites. Synchronizes and updates the project site memberships and groups.

Each service namespace includes all of the DataSet schema and event handler classes that the service uses. For example, Calendar.svc (or Calendar.asmx?wsdl for the ASMX web service) describes the Calendar service. If you name the reference WebSvcCalendar, the proxy namespace contains the primary Calendar class with the methods CheckInCalendars, CheckOutCalendars, and so on. The WebSvcCalendar proxy namespace also includes the CalendarDataSet class and all of its subclasses.

Some of the PSI services contain duplicate DataSet classes. For example, the Project service and the Statusing service both include the ProjectDataSet class. This is because methods in both the Project service and the Statusing service include references to the ProjectDataSet, and the proxy assemblies that you create when you set references and compile an application include the related datasets. The Project service and Statusing service can require values for different fields in the ProjectDataSet.ProjectRow class.

When you are navigating the namespaces and classes of the PSI reference, for example to see the web methods for the Project service, expand the [Project web service] namespace in the Contents list, and then expand the Project class.

See also