feat: add email template implementation for cassandra provider

server/db/providers/cassandradb/email_template.go

@@ -2,10 +2,15 @@ package cassandradb
 
 import (
 	"context"
+	"encoding/json"
+	"fmt"
+	"reflect"
+	"strings"
 	"time"
 
 	"github.com/authorizerdev/authorizer/server/db/models"
 	"github.com/authorizerdev/authorizer/server/graph/model"
+	"github.com/gocql/gocql"
 	"github.com/google/uuid"
 )
 
@@ -18,31 +23,137 @@ func (p *provider) AddEmailTemplate(ctx context.Context, emailTemplate models.Em
 	emailTemplate.Key = emailTemplate.ID
 	emailTemplate.CreatedAt = time.Now().Unix()
 	emailTemplate.UpdatedAt = time.Now().Unix()
+
+	existingEmailTemplate, _ := p.GetEmailTemplateByEventName(ctx, emailTemplate.EventName)
+	if existingEmailTemplate != nil {
+		return nil, fmt.Errorf("Email template with %s event_name already exists", emailTemplate.EventName)
+	}
+
+	insertQuery := fmt.Sprintf("INSERT INTO %s (id, event_name, template,  created_at, updated_at) VALUES ('%s', '%s', '%s', %d, %d)", KeySpace+"."+models.Collections.EmailTemplate, emailTemplate.ID, emailTemplate.EventName, emailTemplate.Template, emailTemplate.CreatedAt, emailTemplate.UpdatedAt)
+	err := p.db.Query(insertQuery).Exec()
+	if err != nil {
+		return nil, err
+	}
+
 	return emailTemplate.AsAPIEmailTemplate(), nil
 }
 
 // UpdateEmailTemplate to update EmailTemplate
 func (p *provider) UpdateEmailTemplate(ctx context.Context, emailTemplate models.EmailTemplate) (*model.EmailTemplate, error) {
 	emailTemplate.UpdatedAt = time.Now().Unix()
+
+	bytes, err := json.Marshal(emailTemplate)
+	if err != nil {
+		return nil, err
+	}
+	// use decoder instead of json.Unmarshall, because it converts int64 -> float64 after unmarshalling
+	decoder := json.NewDecoder(strings.NewReader(string(bytes)))
+	decoder.UseNumber()
+	emailTemplateMap := map[string]interface{}{}
+	err = decoder.Decode(&emailTemplateMap)
+	if err != nil {
+		return nil, err
+	}
+
+	updateFields := ""
+	for key, value := range emailTemplateMap {
+		if key == "_id" {
+			continue
+		}
+
+		if key == "_key" {
+			continue
+		}
+
+		if value == nil {
+			updateFields += fmt.Sprintf("%s = null,", key)
+			continue
+		}
+
+		valueType := reflect.TypeOf(value)
+		if valueType.Name() == "string" {
+			updateFields += fmt.Sprintf("%s = '%s', ", key, value.(string))
+		} else {
+			updateFields += fmt.Sprintf("%s = %v, ", key, value)
+		}
+	}
+	updateFields = strings.Trim(updateFields, " ")
+	updateFields = strings.TrimSuffix(updateFields, ",")
+
+	query := fmt.Sprintf("UPDATE %s SET %s WHERE id = '%s'", KeySpace+"."+models.Collections.EmailTemplate, updateFields, emailTemplate.ID)
+	err = p.db.Query(query).Exec()
+	if err != nil {
+		return nil, err
+	}
+
 	return emailTemplate.AsAPIEmailTemplate(), nil
 }
 
 // ListEmailTemplates to list EmailTemplate
 func (p *provider) ListEmailTemplate(ctx context.Context, pagination model.Pagination) (*model.EmailTemplates, error) {
-	return nil, nil
+	emailTemplates := []*model.EmailTemplate{}
+	paginationClone := pagination
+
+	totalCountQuery := fmt.Sprintf(`SELECT COUNT(*) FROM %s`, KeySpace+"."+models.Collections.EmailTemplate)
+	err := p.db.Query(totalCountQuery).Consistency(gocql.One).Scan(&paginationClone.Total)
+	if err != nil {
+		return nil, err
+	}
+
+	// there is no offset in cassandra
+	// so we fetch till limit + offset
+	// and return the results from offset to limit
+	query := fmt.Sprintf("SELECT id, event_name, template, created_at, updated_at FROM %s LIMIT %d", KeySpace+"."+models.Collections.EmailTemplate, pagination.Limit+pagination.Offset)
+
+	scanner := p.db.Query(query).Iter().Scanner()
+	counter := int64(0)
+	for scanner.Next() {
+		if counter >= pagination.Offset {
+			var emailTemplate models.EmailTemplate
+			err := scanner.Scan(&emailTemplate.ID, &emailTemplate.EventName, &emailTemplate.Template, &emailTemplate.CreatedAt, &emailTemplate.UpdatedAt)
+			if err != nil {
+				return nil, err
+			}
+			emailTemplates = append(emailTemplates, emailTemplate.AsAPIEmailTemplate())
+		}
+		counter++
+	}
+
+	return &model.EmailTemplates{
+		Pagination:     &paginationClone,
+		EmailTemplates: emailTemplates,
+	}, nil
 }
 
 // GetEmailTemplateByID to get EmailTemplate by id
-func (p *provider) GetEmailTemplateByID(ctx context.Context, EmailTemplateID string) (*model.EmailTemplate, error) {
-	return nil, nil
+func (p *provider) GetEmailTemplateByID(ctx context.Context, emailTemplateID string) (*model.EmailTemplate, error) {
+	var emailTemplate models.EmailTemplate
+	query := fmt.Sprintf(`SELECT id, event_name, template, created_at, updated_at FROM %s WHERE id = '%s' LIMIT 1`, KeySpace+"."+models.Collections.EmailTemplate, emailTemplateID)
+	err := p.db.Query(query).Consistency(gocql.One).Scan(&emailTemplate.ID, &emailTemplate.EventName, &emailTemplate.Template, &emailTemplate.CreatedAt, &emailTemplate.UpdatedAt)
+	if err != nil {
+		return nil, err
+	}
+	return emailTemplate.AsAPIEmailTemplate(), nil
 }
 
 // GetEmailTemplateByEventName to get EmailTemplate by event_name
 func (p *provider) GetEmailTemplateByEventName(ctx context.Context, eventName string) (*model.EmailTemplate, error) {
-	return nil, nil
+	var emailTemplate models.EmailTemplate
+	query := fmt.Sprintf(`SELECT id, event_name, template, created_at, updated_at FROM %s WHERE event_name = '%s' LIMIT 1 ALLOW FILTERING`, KeySpace+"."+models.Collections.EmailTemplate, eventName)
+	err := p.db.Query(query).Consistency(gocql.One).Scan(&emailTemplate.ID, &emailTemplate.EventName, &emailTemplate.Template, &emailTemplate.CreatedAt, &emailTemplate.UpdatedAt)
+	if err != nil {
+		return nil, err
+	}
+	return emailTemplate.AsAPIEmailTemplate(), nil
 }
 
 // DeleteEmailTemplate to delete EmailTemplate
-func (p *provider) DeleteEmailTemplate(ctx context.Context, EmailTemplate *model.EmailTemplate) error {
+func (p *provider) DeleteEmailTemplate(ctx context.Context, emailTemplate *model.EmailTemplate) error {
+	query := fmt.Sprintf("DELETE FROM %s WHERE id = '%s'", KeySpace+"."+models.Collections.EmailTemplate, emailTemplate.ID)
+	err := p.db.Query(query).Exec()
+	if err != nil {
+		return err
+	}
+
 	return nil
 }