Add functionality to export retrospective as PDF

Author: Mewbi

go.mod

@@ -19,6 +19,7 @@ require (
 	github.com/bytedance/sonic/loader v0.2.4 // indirect
 	github.com/cloudwego/base64x v0.1.5 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/go-pdf/fpdf v0.9.0 // indirect
 	github.com/gorilla/context v1.1.2 // indirect
 	github.com/gorilla/securecookie v1.1.2 // indirect
 	github.com/gorilla/sessions v1.4.0 // indirect

go.sum

@@ -32,6 +32,8 @@ github.com/go-openapi/spec v0.20.14 h1:7CBlRnw+mtjFGlPDRZmAMnq35cRzI91xj03HVyUi/
 github.com/go-openapi/spec v0.20.14/go.mod h1:8EOhTpBoFiask8rrgwbLC3zmJfz4zsCUueRuPM6GNkw=
 github.com/go-openapi/swag v0.22.9 h1:XX2DssF+mQKM2DHsbgZK74y/zj4mo9I99+89xUmuZCE=
 github.com/go-openapi/swag v0.22.9/go.mod h1:3/OXnFfnMAwBD099SwYRk7GD3xOrr1iL7d/XNLXVVwE=
+github.com/go-pdf/fpdf v0.9.0 h1:PPvSaUuo1iMi9KkaAn90NuKi+P4gwMedWPHhj8YlJQw=
+github.com/go-pdf/fpdf v0.9.0/go.mod h1:oO8N111TkmKb9D7VvWGLvLJlaZUQVPM+6V42pp3iV4Y=
 github.com/go-playground/assert/v2 v2.2.0 h1:JvknZsQTYeFEAhQwI4qEt9cyV5ONwRHC+lYKSsYSR8s=
 github.com/go-playground/assert/v2 v2.2.0/go.mod h1:VDjEfimB/XKnb+ZQfWdccd7VUvScMdVu0Titje2rxJ4=
 github.com/go-playground/locales v0.14.1 h1:EWaQ/wswjilfKLTECiXz7Rh+3BjFhfDFKv/oXslEjJA=

internal/server/server.go

@@ -715,8 +715,9 @@ func (ct *Controller) voteAnswer(c *gin.Context) {
 //	@Accept		json
 //	@Produce	json
 //	@Produce	text/markdown
+//	@Produce	application/pdf
 //	@Param		export	body		types.RetrospectiveExportRequest	true	"Export Retrospective"
-//	@Success	200		{object}	types.Retrospective					"Retrospective Object (JSON) or Markdown file"
+//	@Success	200		{object}	types.Retrospective					"Retrospective Object (JSON), Markdown file, or PDF file"
 //	@Failure	400		{string}	string								"Invalid input"
 //	@Failure	404		{string}	string								"Not Found"
 //	@Failure	500		{string}	string								"Internal error"
@@ -751,11 +752,20 @@ func (ct *Controller) exportRetrospective(c *gin.Context) {
 	filename := fmt.Sprintf("retrospective-%s", strings.ReplaceAll(retro.Name, " ", "_"))
 	switch input.ExportType {
 	case types.ExportTypeMarkdown:
-
 		markdown := ct.service.ConvertRetrospectiveToMarkdown(c, retro)
 		c.Header("Content-Type", "text/markdown")
 		c.Header("Content-Disposition", fmt.Sprintf("attachment; filename=\"%s.md\"", filename))
 		c.String(http.StatusOK, markdown)
+	case types.ExportTypePDF:
+		pdfBytes, err := ct.service.ConvertRetrospectiveToPDF(c, retro)
+		if err != nil {
+			ct.logger.Error("error converting retrospective to PDF", zap.Error(err))
+			c.JSON(http.StatusInternalServerError, gin.H{"error": "error generating PDF"})
+			return
+		}
+		c.Header("Content-Type", "application/pdf")
+		c.Header("Content-Disposition", fmt.Sprintf("attachment; filename=\"%s.pdf\"", filename))
+		c.Data(http.StatusOK, "application/pdf", pdfBytes)
 	default:
 		c.Header("Content-Type", "application/json")
 		c.Header("Content-Disposition", fmt.Sprintf("attachment; filename=\"%s.json\"", filename))

internal/service/convert.go

@@ -1,11 +1,15 @@
 package service
 
 import (
-	"api/types"
+	"bytes"
 	"context"
 	"fmt"
 	"sort"
 	"strings"
+
+	"api/types"
+
+	"github.com/go-pdf/fpdf"
 )
 
 func (s *Service) ConvertRetrospectiveToMarkdown(ctx context.Context, retro *types.Retrospective) string {
@@ -44,3 +48,73 @@ func (s *Service) ConvertRetrospectiveToMarkdown(ctx context.Context, retro *typ
 
 	return sb.String()
 }
+
+func (s *Service) ConvertRetrospectiveToPDF(ctx context.Context, retro *types.Retrospective) ([]byte, error) {
+	pdf := fpdf.New("P", "mm", "A4", "")
+	pdf.SetMargins(20, 20, 20)
+	pdf.AddPage()
+
+	// Title
+	pdf.SetFont("Arial", "B", 24)
+	pdf.Cell(0, 12, "Simple Retro")
+	pdf.Ln(16)
+
+	// Subtitle (retrospective name)
+	pdf.SetFont("Arial", "B", 18)
+	pdf.Cell(0, 10, retro.Name)
+	pdf.Ln(12)
+
+	// Description
+	if retro.Description != "" {
+		pdf.SetFont("Arial", "", 12)
+		pdf.MultiCell(0, 6, retro.Description, "", "", false)
+		pdf.Ln(4)
+	}
+
+	// Created at
+	pdf.SetFont("Arial", "I", 10)
+	pdf.SetTextColor(128, 128, 128)
+	pdf.Cell(0, 6, "Created on "+retro.CreatedAt.Format("January 2, 2006 at 3:04 PM"))
+	pdf.Ln(10)
+	pdf.SetTextColor(0, 0, 0)
+
+	// Separator line
+	pdf.Line(20, pdf.GetY(), 190, pdf.GetY())
+	pdf.Ln(8)
+
+	// Questions and answers
+	for _, question := range retro.Questions {
+		// Question title
+		pdf.SetFont("Arial", "B", 14)
+		pdf.MultiCell(0, 8, question.Text, "", "", false)
+		pdf.Ln(4)
+
+		// Sort answers by position
+		answers := make([]types.Answer, len(question.Answers))
+		copy(answers, question.Answers)
+		sort.Slice(answers, func(i, j int) bool {
+			return answers[i].Position < answers[j].Position
+		})
+
+		pdf.SetFont("Arial", "", 11)
+		for _, answer := range answers {
+			var text string
+			if answer.Votes > 0 {
+				text = fmt.Sprintf("  - %s (%d votes)", answer.Text, answer.Votes)
+			} else {
+				text = fmt.Sprintf("  - %s", answer.Text)
+			}
+			pdf.MultiCell(0, 6, text, "", "", false)
+			pdf.Ln(1)
+		}
+		pdf.Ln(6)
+	}
+
+	var buf bytes.Buffer
+	err := pdf.Output(&buf)
+	if err != nil {
+		return nil, err
+	}
+
+	return buf.Bytes(), nil
+}

types/retrospective.go

@@ -15,6 +15,7 @@ const (
 
 	ExportTypeJSON     ExportType = "JSON"
 	ExportTypeMarkdown ExportType = "MARKDOWN"
+	ExportTypePDF      ExportType = "PDF"
 )
 
 type Retrospective struct {

types/validations.go

@@ -121,7 +121,7 @@ func (r RetrospectiveExportRequest) Validate() error {
 	}
 
 	switch r.ExportType {
-	case ExportTypeJSON, ExportTypeMarkdown:
+	case ExportTypeJSON, ExportTypeMarkdown, ExportTypePDF:
 		return nil
 	default:
 		return fmt.Errorf("invalid export type")