redesign structure, add get endpoint

internal/application/application.go

@@ -1,8 +1,8 @@
 package application
 
 import (
-	"vegan-barcode/internal/application/utils"
 	"vegan-barcode/internal/database"
+	"vegan-barcode/internal/utils"
 
 	"github.com/sirupsen/logrus"
 )

internal/application/handlers.go

@@ -1,11 +1,19 @@
 package application
 
-import "github.com/gin-gonic/gin"
+import (
+	"net/http"
 
-func (application *Application) GetClaimsHandler(c *gin.Context) {
+	"github.com/gin-gonic/gin"
+)
+
+func (a *Application) GetClaimsHandler(c *gin.Context) {
 	system := c.DefaultQuery("system", "upc")
 	barcode := c.Query("barcode")
 
-	application.GetClaims(system, barcode)
-	// TODO: 404 when claims are not found
+	productClaims, err := a.GetClaims(system, barcode)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, nil)
+		return
+	}
+	c.JSON(http.StatusOK, productClaims)
 }

internal/application/routes.go

@@ -4,7 +4,6 @@ import (
 	"github.com/gin-gonic/gin"
 )
 
-// TODO: Service should get moved somewhere else. Not sure on naming.
 func (application *Application) bindRoutes() {
 
 	router := gin.Default()

internal/application/services.go

@@ -1,5 +1,19 @@
 package application
 
-func (application *Application) GetClaims(system string, barcode string) {
-	application.db.FindClaimsByBarcode(system, barcode)
+import (
+	"vegan-barcode/internal/models"
+)
+
+func (a *Application) GetClaims(system string, barcode string) (*models.ProductClaims, error) {
+	id, err := a.db.FindProductIDByBarcode(system, barcode)
+	if err != nil {
+		return nil, err
+	}
+
+	claims, err := a.db.FindClaimsByProductID(id)
+	if err != nil {
+		return nil, err
+	}
+
+	return &models.ProductClaims{Id: id, Claims: claims}, nil
 }

internal/database/claims.go

@@ -2,9 +2,53 @@ package database
 
 import (
 	"context"
+	"vegan-barcode/internal/models"
 )
 
-func (database *Database) FindClaimsByBarcode(system string, barcode string) {
+func (database *Database) FindClaimsByProductID(product_id int) (claims []models.Claim, err error) {
 	ctx := context.Background()
-	database.db.Exec(ctx, "SELECT * FROM user_claims")
+	err = database.db.Query(ctx, claims, `SELECT
+    cluster,
+    id,
+    worker_type,
+    evidence_type,
+    evidence,
+    category,
+    polarity,
+    created_at,
+    created_by
+FROM (
+    SELECT
+        cluster,
+        id,
+        worker_type,
+        evidence_type,
+        evidence,
+        category,
+        polarity,
+        created_at,
+        created_by,
+        ROW_NUMBER() OVER (PARTITION BY category ORDER BY created_at DESC) AS rn
+    FROM (
+        (
+            SELECT "user" as cluster, id, product_id, null as worker_type, evidence_type, evidence, unnest(claim) as category, true as polarity, created_at, created_by FROM user_claims
+            UNION ALL
+            SELECT "automated" as cluster, id, product_id, worker_type, null as evidence_type, evidence, unnest(claim) as category, true as polarity, created_at, null as created_by FROM automated_claims
+        )
+        UNION ALL
+        (
+            SELECT "user" as cluster, id, product_id, null as worker_type, evidence_type, evidence, unnest(counter_claim) as category, false as polarity, created_at, created_by FROM user_claims
+            UNION ALL
+            SELECT "automated" as cluster, id, product_id, worker_type, null as evidence_type, evidence, unnest(counter_claim) as category, false as polarity, created_at, null as created_by FROM automated_claims
+        )
+    )
+    WHERE product_id = ?
+)
+WHERE rn = 1
+ORDER BY created_at;
+`, product_id)
+	if err != nil {
+		return claims, err
+	}
+	return
 }

internal/database/database.go

@@ -16,6 +16,7 @@ var UserClaimsTable = ksql.NewTable("user_claims", "id")
 
 var AutomatedClaimsTable = ksql.NewTable("automated_claims", "id")
 
+// Struct used in dependency injection can be replaced with a mock for testing.
 type Database struct {
 	db *ksql.DB
 }

internal/database/models.go

@@ -2,6 +2,7 @@ package database
 
 import (
 	"time"
+	"vegan-barcode/internal/models"
 )
 
 type Product struct {
@@ -11,54 +12,23 @@ type Product struct {
 	Created_at time.Time `ksql:"created_at,timeNowUTC"`
 }
 
-type WorkerType int
-
-const (
-	Barnivore WorkerType = iota
-)
-
-type EvidenceType int
-
-const (
-	ManufactureWebsite EvidenceType = iota
-	IngredientsList
-)
-
-type Claim int
-
-const (
-	ContainsMeat Claim = iota
-	ContainsFish
-	ContainsEggs
-	ContainsMilk
-	ContainsHoney
-	ContainsWax
-	ContainsFur
-	ContainsLeather
-	ContainsAnimalFibers
-	ContainsWool
-	ContainsFeathers
-	AnimalTesting
-	MonkeySlavery
-)
-
 type AutomatedClaim struct {
-	id            int        `ksql:"id"`
-	product_id    int        `ksql:"product_id"`
-	worker_type   WorkerType `ksql:"worker_type"`
-	evidence      struct{}   `ksql:"evidence,json"`
-	claim         Claim      `ksql:"claim"`
-	counter_claim Claim      `ksql:"counter_claim"`
-	created_at    time.Time  `ksql:"created_at,timeNowUTC"`
+	id            int               `ksql:"id"`
+	product_id    int               `ksql:"product_id"`
+	worker_type   models.WorkerType `ksql:"worker_type"`
+	evidence      struct{}          `ksql:"evidence,json"`
+	claim         models.ClaimType  `ksql:"claim"`
+	counter_claim models.ClaimType  `ksql:"counter_claim"`
+	created_at    time.Time         `ksql:"created_at,timeNowUTC"`
 }
 
 type UserClaim struct {
-	id            int          `ksql:"id"`
-	product_id    int          `ksql:"product_id"`
-	evidence_type EvidenceType `ksql:"evidence_type"`
-	evidence      struct{}     `ksql:"evidence,json"`
-	claim         Claim        `ksql:"claim"`
-	counter_claim Claim        `ksql:"counter_claim"`
-	created_at    time.Time    `ksql:"created_at,timeNowUTC"`
-	created_by    string       `ksql:"created_by"`
+	id            int                 `ksql:"id"`
+	product_id    int                 `ksql:"product_id"`
+	evidence_type models.EvidenceType `ksql:"evidence_type"`
+	evidence      struct{}            `ksql:"evidence,json"`
+	claim         models.ClaimType    `ksql:"claim"`
+	counter_claim models.ClaimType    `ksql:"counter_claim"`
+	created_at    time.Time           `ksql:"created_at,timeNowUTC"`
+	created_by    string              `ksql:"created_by"`
 }

internal/database/products.go

@@ -0,0 +1,14 @@
+package database
+
+import "context"
+
+func (d *Database) FindProductIDByBarcode(system string, barcode string) (id int, err error) {
+
+	ctx := context.Background()
+
+	err = d.db.QueryOne(ctx, &id, "SELECT id FROM products WHERE system = ? AND barcode = ?", system, barcode)
+	if err != nil {
+		return -1, err
+	}
+	return
+}

internal/models/models.go

@@ -0,0 +1,61 @@
+package models
+
+import (
+	"time"
+)
+
+type ClaimType int
+
+const (
+	ContainsMeat ClaimType = iota
+	ContainsFish
+	ContainsEggs
+	ContainsMilk
+	ContainsHoney
+	ContainsWax
+	ContainsFur
+	ContainsLeather
+	ContainsAnimalFibers
+	ContainsWool
+	ContainsFeathers
+	AnimalTesting
+	MonkeySlavery
+)
+
+type WorkerType int
+
+const (
+	Barnivore WorkerType = iota
+)
+
+type EvidenceType int
+
+const (
+	ManufactureWebsite EvidenceType = iota
+	IngredientsList
+)
+
+type ClusterType int
+
+const (
+	User ClusterType = iota
+	Automated
+)
+
+// Generic claim type for combining both automated and user claims.
+type Claim struct {
+	Id            int
+	Worker_type   WorkerType
+	Evidence_type EvidenceType
+	Evidence      struct{}
+	Category      ClaimType
+	Polarity      bool
+	Created_at    time.Time
+	Created_by    string
+	Cluster       ClusterType
+}
+
+type ProductClaims struct {
+	Id     int
+	Claims []Claim
+}