---
title: "Integration with External Services via gRPC"
slug: "integration-with-external-services-via-grpc"
updated: 2026-07-27T20:50:08Z
published: 2026-07-27T20:50:08Z
canonical: "documentation.decisions.com/integration-with-external-services-via-grpc"
stale: true
---

> ## Documentation Index
> Fetch the complete documentation index at: https://documentation.decisions.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Integration with External Services via gRPC

## Overview

[gRPC](https://grpc.io/docs/what-is-grpc/) (Remote Procedure Call) is an open-source remote procedure call framework that allows client and server applications to communicate efficiently. It is commonly used in distributed systems, microservices, and server-to-server integrations where performance and structured communication are important.

gRPC uses protocol buffers, also known as `.proto` files, to define available services, methods, and message types. These definitions allow Decisions to understand how to communicate with the external gRPC server and make the available methods usable as Flow steps.

AvailabilitySupport for gRPC external service integrations is available in Decisions version **9.15** and later.

---

## Settings and Results

The following tables describe the settings used to configure a gRPC service and the expected outputs created by the integration.

**Inputs**

| Setting | Description | Data Type |
| --- | --- | --- |
| Name | User-defined name for the gRPC service reference. Steps with this name will be available in the toolbox under **Integration** **> External Services**. | Text |
| Description | Description of what the gRPC Service is intended for. | Text |
| Service URL | Specifies the address where the application will send requests to or receive responses from. | URL/Text. It typically includes the protocol (e.g., http:// or https://) and the domain or IP address of the web service. |
| Service Definition Proto Files | The `.proto` files define the gRPC services, available RPC methods, and message types used by the integration. They provide the structure the client needs to communicate with the gRPC server correctly. | Selection List. The Options are: - From Zip File - From URL |
| Reflection URL | The address of a gRPC server that exposes the gRPC Server Reflection service. It displays if the RPC method is **From URL**. | URL / Text |
| Proto File Directory Zip | A ZIP archive containing a directory of .proto files and any imported dependencies. It displays if the RPC method is **From Zip File**. | File |
| Services to Include | Specifies which gRPC services to include from the provided .proto definitions. | Selection List |
| Additional HTTP Headers | Custom metadata headers to send with every gRPC request. | Key/Value List |
| Authentication Type | Determines how the client authenticates with the gRPC server. | Selection List. The options are: - No Authentication - Use Basic Authentication - Use Windows Auth (Requires Advanced Setup) - Use OAuth |
| Ignore Server Certificate Errors | If enabled, the client accepts invalid or untrusted TLS certificates. This option is not recommended unless used for development or testing. | Boolean (Toggle) |
| Enable Mutual Authentication | Enables mutual TLS, where both the client and server authenticate each other using TLS certificates. If enabled, a P12/PFX Certificate and P12/PFX Password must be provided. | Boolean (Toggle) |

**Outputs**

| Output | Description | Data Type |
| --- | --- | --- |
| gRPC Methods | Flows in the Designer Folder displays the service methods imported from the .proto file(s) as steps. | Service Methods |

---

## Example: Route Guide

The following example utilizes the Route Guide example. It was configured with the open-source instructions found [here](https://grpc.io/docs/languages/go/basics/).

1. Navigate to **Project > Manage > Integrations > External Services**. From the top menu, click **Add gRPC Service**.
2. Provide a name for the service, define the service URL, and upload the .proto files from a zip file. Select RouteGuide (in route_guide.proto) under Services to Include. Hit **S****ave Integration**.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/image-1784925793240.png)
3. After creating the service, go to the Designer Folder and create a Flow. Open the Toolbox and navigate to **Integration > GRPC > GRPC_Service > RouteGuide.** The service methods imported from the .proto file(s) will appear as steps. Drag over any steps to the workspace, and connect the step to the **Start** and **End** steps. ![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/image-1783434309544.png)
4. Click **Debug** on the top action bar to review the output of each step.