Go-Soap

Go-Soap is an open-source library for handling SOAP requests and responses in Go.

Features

• Easy to understand functions for making SOAP requests
• Ability to add headers
• Able to parse responses into dynamic objects for easy data retrieval

Installation

You can install Soap using Go modules:

go get github.com/ben-meeker/go-soap

Getting Started

Please see the examples folder for working builds that use this library

1. In your Go code, import the Soap package:

   import (
       "github.com/ben-meeker/go-soap"
   )

2. Create a struct to house relevant data

   type FahrenheitToCelsius struct {
       Fahrenheit float64
       Celsius    float64
   }

3. Create a new XML file template using the struct field name inside curly braces as variable placeholders. You can also dotwalk by using the following syntax, if your structs are nested: {InputValues.Fahrenheit} (see examples folder)

   <?xml version="1.0" encoding="utf-8"?>
   <soap12:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap12="http://www.w3.org/2003/05/soap-envelope">
   <soap12:Body>
     <FahrenheitToCelsius xmlns="https://www.w3schools.com/xml/">
        <Fahrenheit>{Fahrenheit}</Fahrenheit>
     </FahrenheitToCelsius>
   </soap12:Body>
   </soap12:Envelope>

4. Set your endpoint URL

   const url string = "https://www.w3schools.com/xml/tempconvert.asmx"

5. Use the GetTemplate function to load your template into Go

   template, err := soap.GetTemplate("fahrenheit_to_celsius.xml")
   if err != nil {
       fmt.Println(err)
    }

   This will return an error if unable to fetch the template provided

6. Create headers in a type map[string]string

   headers := make(map[string]string)
    headers["Content-Type"] = "application/soap+xml; charset=utf-8"

7. Use the SoapCall function to make the request

   res, err := soap.SoapCall(url, headers, template, values)
    if err != nil {
    	panic(err)
    }

   This will look at the number of paramters provided, and compare it to the number of parameters detected in your template designated by the %v placeholder. If they do not match, or there is an error making the request, the function will return an error.

8. Use the ParseXMLResponse function to create a readable object from the XML response

   xmlRes, err := soap.ParseXMLResponse(res)
    if err != nil {
    	fmt.Println(err)
    }

   This will parse the data into a series of XMLObject that contain a Contents field of type map[string]any . This may contain another XMLObject if nesting has occured, or will have a value designated by the key value

9. To view the structure of the response, print the Structure field of your XMLResponse object

    fmt.Println(xmlRes.Structure)

10. To access a value from the object, use the syntax below to drill down to the location, and access it using .Value this will always be a string

celsiusString := xmlRes.Body.Children["soap:Envelope"].Children["soap:Body"].Children["FahrenheitToCelsiusResponse"].Children["FahrenheitToCelsiusResult"].Value

11. Use the strconv package to convert your value to a type that matches your struct and assign it to a field

values.Celsius, err = strconv.ParseFloat(celsiusString, 64)
 if err != nil {
 	fmt.Println(err)
 }
 fmt.Println(values)

Full code:

 package main

import (
   "fmt"
   "strconv"

   "github.com/ben-meeker/soap" // Will be go-soap on non-local imports
)

// Create struct to fill request body with
// Fields must be exported or available in package, or you will get an error
// populating them into the template
type FahrenheitToCelsius struct {
   Fahrenheit float64
   Celsius    float64
}

func main() {
   // Set endpoint URL
   const url string = "https://www.w3schools.com/xml/tempconvert.asmx"

   // Retrieve farenheit_to_celsius.xml template
   template, err := soap.GetTemplate("fahrenheit_to_celsius.xml")
   if err != nil {
      fmt.Println(err)
   }

   // Set values based on template requirements
   // In this case, the only required value is fahrenheit
   values := FahrenheitToCelsius{
      Fahrenheit: 75,
   }

   // Set headers
   headers := make(map[string]string)
   headers["Content-Type"] = "application/soap+xml; charset=utf-8"

   // Make SOAP call with standard content/type
   res, err := soap.SoapCall(url, headers, template, values)
   if err != nil {
      // Handle error
      panic(err)
   }

   // Parse XML response
   xmlRes, err := soap.ParseXMLResponse(res)
   if err != nil {
      fmt.Println(err)
   }

   // View structure of XML response
   fmt.Println(xmlRes.Structure)

   // Get value from XML response                         // Reference Children          // Key                                    // Value will always be a string
   celsiusString := xmlRes.Body.Children["soap:Envelope"].Children["soap:Body"].Children["FahrenheitToCelsiusResponse"].Children["FahrenheitToCelsiusResult"].Value
   // Convert value type to match struct
   values.Celsius, err = strconv.ParseFloat(celsiusString, 64)
   if err != nil {
      // Handle error
      fmt.Println(err)
   }
   fmt.Println(values)
}

Contribute

If you want to contribute to this project, feel free to open a PR or an issue.