Enterprise Administration > Implementing Windchill ESI > Implementing Windchill ESI in an SAP Environment > Understanding Windchill ESI Architecture > Windchill ESI Services > Remote Procedure Calls (RPC)
  
Remote Procedure Calls (RPC)
Windchill ESI services provide the following query RPCs:
• GetPart: This RPC obtains information about aWindchill PDMLink part. Optionally, it returns information about alternates of the part or documents that are associated with the part.
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With a certain attribute (under the Part Settings section in the Define Settings and Parameters step of the Create/Edit Distribution Target UI) set on the distribution target, control characteristics associated to a part (and to its alternates when the Publish Alternates attribute is set) are returned as well. This is done regardless of whether the part is released as a standalone object, or in association with an assembly, a change notice, a process plan or a promotion request.
• GetBOM: This RPC obtains information about aWindchill PDMLink assembly. This is represented in the distribution target as a Bill of Materials (BOM). A default or any other type of saved filter can be used for navigating the assembly. One or multiple levels can be specified. An option is available to indicate whether Windchill ESI uses line numbers. If you set certain attributes on the distribution target for the invoked RPC, you can request the following:
◦ Changes since the last retrieval
◦ Alternates of the parts on the product structure
◦ Documents that are associated to the parts on the product structure (or to their alternates)
◦ Parts that may be used as substitutes for components on the product structure
◦ Reference designators associated with the parts
• Get Document: Obtains information about a Windchill PDMLink document (which includes both WTDocuments and CAD documents) or about a CAD document structure. To configure the various options for this RPC, refer to the attributes under the CAD Document Settings section in the Define Settings and Parameters step of the Create/Edit Distribution Target UI
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The fields under theCAD Document Settings section are applicable only to CAD document structures, and have no impact on standalone documents. Also, these settings are used regardless of whether the structure was released as a standalone object, or in association with a Change Notice or a promotion request.
• GetProcessPlan: This RPC obtains information about Windchill MPMLink process plan along with the associated BOM information. To configure the various options for this RPC, refer to the fields provided in the New Distribution Target or Edit Distribution Target windows. You can access these windows by navigating to the Utilities page, and clicking Manage Distribution. The relevant attributes to set are those that appear in the Define Settings and Parameters step of the window, under the process plan settings.
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With a certain attribute (under the Process Plan Settings section in the Define Settings and Parameters step of the Create/Edit Distribution Target UI) set on the distribution target, control characteristics associated to a process plan are returned as well. This is done regardless of whether the process plan is released as a standalone object, or in association with a change notice or a promotion request. Also, with this attribute set to Yes, control characteristics associated to a related operation are returned as well, regardless of the value of the corresponding attribute for parts, even if those control characteristics are also associated to a part.
• GetResource: This RPC obtains information about a Windchill MPMLink resource, such as a Process Material, a Tooling or a Skill. To configure the various options for this RPC, refer to the fields provided in the New Distribution Target or Edit Distribution Target UI. You can access both the New Distribution Target and Edit Distribution Target windows by clicking Site > Utilities > Manage Distribution. In the Define Settings and Parameters step use the attributes provided in the Resource Settings section.
• GetECN: This RPC obtains information about aWindchill PDMLink change order and its related parts and assemblies, documents, CAD document structures, process plans and resources. The optional behaviors are similar to those described for GetPart, GetBOM, GetDocument, GetProcessPlan and GetResource RPCs. However, to configure the options for GetECN, distribution target attributes in the Change Notice Settings section need to be set from the Define Settings and Parameters step brought up by clicking the Utilities > Manage Distribution.
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When processing a related CAD document structure, ESI services make use of the attributes in the CAD Document Settings section instead of those in the Change Notice Settings section.
• GetPromotionRequest: Obtains information about a Windchill PDMLink Promotion Request and its promotables such as parts, assemblies, documents, CAD document structures, process plans and resources. No options that are specific to a promotion request exit. However, when processing a promotable that resides in a promotion request, options that apply to that object type are used.
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Windchill ESI services do not use any of the above described query RPCs by default. They invoke the corresponding getXXX() open APIs to obtain the required product information.
Windchill ESI services provide the following two transaction management RPCs:
• PostResult: This RPC records the result of an attempt to public an object to a distribution target, and when applicable, notifies a suspendedWindchill PDMLink workflow to resume processing by invoking the postEvent() API.
• PostEvent: This RPC notifies a suspendedWindchill PDMLink workflow to resume processing.
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Since the PostResult RPC invokes the postEvent() open API internally, Windchill ESI services do not use the PostEvent RPC by default.