Exporting only a specific set of pages in Go with Net/HTTP

In this guide, we'll show you how to export only a specific set of pages from a document using Go and the Net/HTTP library to convert them to PDF using PDFShift's API.

When you're converting a document, you might want to export only a specific set of pages from a document. This can be done by setting the pages parameter to the request.

It behaves exactly like the page parameter you can see when you print a document from your browser.

It accepts the following pattern:

A number, such as 2. This will print the page 2
A range, such as 2-4. This will print the pages 2 to 4 (2, 3 and 4)
A list, such as 2,4,5,9. This will print the pages 2, 4, 5 and 9

This way, you can only export the pages that you really need and get immediately the result you want in the PDF, without having to edit it.

Here's an example:

package main

import (
    "bytes"
    "encoding/base64"
    "encoding/json"
    "fmt"
    "io/ioutil"
    "net/http"
)

func main() {
    // You can get an API key at https://pdfshift.io
    apiKey := "sk_xxxxxxxxxxxx"

    params := map[string]interface{}{
        "source": "https://en.wikipedia.org/wiki/PDF",
        "pages":  "2-4",
    }

    // Marshal the parameters into JSON
    jsonParams, err := json.Marshal(params)
    if err != nil {
        fmt.Println("Error marshaling JSON:", err)
        return
    }

    // Create a new HTTP client
    client := &http.Client{}

    // Create a new request
    req, err := http.NewRequest("POST", "https://api.pdfshift.io/v3/convert/pdf", bytes.NewBuffer(jsonParams))
    if err != nil {
        fmt.Println("Error creating request:", err)
        return
    }

    // Set request headers
    req.Header.Set("Content-Type", "application/json")

    // Set basic authentication header
    auth := "api:" + apiKey
    req.Header.Set("Authorization", "Basic "+base64.StdEncoding.EncodeToString([]byte(auth)))

    // Perform the request
    resp, err := client.Do(req)
    if err != nil {
        fmt.Println("Error performing request:", err)
        return
    }
    defer resp.Body.Close()

    // Read response body
    body, err := ioutil.ReadAll(resp.Body)
    if err != nil {
        fmt.Println("Error reading response body:", err)
        return
    }

    // Check response status code
    if resp.StatusCode >= 400 {
        fmt.Printf("Request failed with status code %d: %s\n", resp.StatusCode, string(body))
        return
    }

    // Save the PDF document
    err = ioutil.WriteFile("result.pdf", body, 0644)
    if err != nil {
        fmt.Println("Error saving PDF document:", err)
        return
    }

    fmt.Println("The PDF document was generated and saved to result.pdf")
}

For further details on the pages property and its usage, please refer to our dedicated documentation.

We hope this guide was helpful. If you have any questions or noticed any issues on the code above,
feel free to drop us a line.