implement api/cart

backend/prepare.sql

@@ -42,9 +42,12 @@ CREATE TABLE IF NOT EXISTS carts (
 CREATE TABLE IF NOT EXISTS cart_items (
     id INTEGER PRIMARY KEY,
     cart INTEGER NOT NULL,
+    product INTEGER NOT NULL,
     amount INTEGER NOT NULL,
 
-    FOREIGN KEY(cart) REFERENCES carts(id)
+
+    FOREIGN KEY(cart) REFERENCES carts(id),
+    FOREIGN KEY(product) REFERENCES product(id)
 );
 
 

backend/src/controllers.h

@@ -32,6 +32,8 @@ void route_get_not_found(HttpCtx* ctx);
 
 void route_get_products_all(HttpCtx* ctx);
 
+void route_get_cart_items_from_session(HttpCtx* ctx);
+
 void route_post_users_register(HttpCtx* ctx);
 
 void route_post_sessions_login(HttpCtx* ctx);

backend/src/controllers/carts.c

@@ -0,0 +1,42 @@
+#include "../controllers.h"
+#include "../http_server.h"
+#include "../models_json.h"
+#include "../str_util.h"
+
+void route_get_cart_items_from_session(HttpCtx* ctx)
+{
+    Cx* cx = http_ctx_user_ctx(ctx);
+    const Session* session = middleware_session(ctx);
+    if (!session)
+        return;
+
+
+    CartItemVec cart_items;
+    cart_item_vec_construct(&cart_items);
+
+    DbRes db_res = db_cart_items_with_user_id(cx->db, &cart_items, session->user_id);
+    if (db_res != DbRes_Ok) {
+        RESPOND_BAD_REQUEST(ctx, "Could not find cart for user");
+        return;
+    }
+
+
+    String res;
+    string_construct(&res);
+
+    string_push_str(&res, "{\"ok\":true,\"products\":[");
+    for (size_t i = 0; i < cart_items.size; ++i) {
+        if (i != 0) {
+            string_push_str(&res, ",");
+        }
+        char* json = cart_item_to_json_string(&cart_items.data[i]);
+        string_push_str(&res, json);
+        free(json);
+    }
+    string_push_str(&res, "]}");
+
+
+    cart_item_vec_destroy(&cart_items);
+    RESPOND_JSON(ctx, 200, "%s", res.data);
+    string_destroy(&res);
+}

backend/src/controllers/sessions.c

@@ -27,7 +27,7 @@ void route_post_sessions_login(HttpCtx* ctx)
     }
 
     User user;
-    DbRes db_res = db_user_from_email(cx->db, &user, req.email);
+    DbRes db_res = db_user_with_email(cx->db, &user, req.email);
     if (db_res == DbRes_NotFound) {
         RESPOND_BAD_REQUEST(ctx, "user with email not found");
         goto l0_return;
@@ -71,7 +71,7 @@ void route_get_sessions_user(HttpCtx* ctx)
         return;
 
     User user;
-    DbRes db_res = db_user_from_id(cx->db, &user, session->user_id);
+    DbRes db_res = db_user_with_id(cx->db, &user, session->user_id);
     if (db_res != DbRes_Ok) {
         RESPOND_BAD_REQUEST(ctx, "user not found");
         return;

backend/src/db.h

@@ -2,9 +2,12 @@
 
 #include "collection.h"
 #include "models.h"
+#include <stdint.h>
 
 DEFINE_VEC(int64_t, Ids, ids, 8)
 DEFINE_VEC(Product, ProductVec, product_vec, 32)
+DEFINE_VEC(CartItem, CartItemVec, cart_item_vec, 32)
+
 
 typedef enum {
     DbRes_Ok,
@@ -17,7 +20,7 @@ typedef struct Db Db;
 /// `user.id` field is ignored.
 DbRes db_user_insert(Db* db, const User* user);
 /// `user` field is an out parameter. 
-DbRes db_user_from_id(Db* db, User* user, int64_t id);
+DbRes db_user_with_id(Db* db, User* user, int64_t id);
 
 
 /// Expects `ids` to be constructed.
@@ -25,7 +28,10 @@ DbRes db_users_with_email(Db* db, Ids* ids, const char* email);
 
 
 /// `user` is an out parameter.
-DbRes db_user_from_email(Db* db, User* user, const char* email);
+DbRes db_user_with_email(Db* db, User* user, const char* email);
 
 /// Expects `vec` to be constructed.
 DbRes db_product_all(Db* db, ProductVec* vec);
+
+DbRes db_cart_items_with_user_id(Db* db, CartItemVec* vec, int64_t user_id);
+

backend/src/db_sqlite.c

@@ -4,6 +4,7 @@
 #include "str_util.h"
 #include <assert.h>
 #include <sqlite3.h>
+#include <stdint.h>
 #include <stdio.h>
 
 static inline char* get_str_safe(sqlite3_stmt* stmt, int col)
@@ -100,7 +101,7 @@ l0_return:
     return res;
 }
 
-DbRes db_user_from_id(Db* db, User* user, int64_t id)
+DbRes db_user_with_id(Db* db, User* user, int64_t id)
 {
     static_assert(sizeof(User) == 40, "model has changed");
 
@@ -118,7 +119,6 @@ DbRes db_user_from_id(Db* db, User* user, int64_t id)
     int step_res = sqlite3_step(stmt);
     if (step_res == SQLITE_DONE) {
         res = DbRes_NotFound;
-        puts("didn't find user");
         goto l0_return;
     } else if (step_res != SQLITE_ROW) {
         fprintf(stderr, "error: %s\n", sqlite3_errmsg(connection));
@@ -173,7 +173,7 @@ l0_return:
     return res;
 }
 
-DbRes db_user_from_email(Db* db, User* user, const char* email)
+DbRes db_user_with_email(Db* db, User* user, const char* email)
 {
     static_assert(sizeof(User) == 40, "model has changed");
 
@@ -263,3 +263,65 @@ l0_return:
     DISCONNECT;
     return res;
 }
+
+
+DbRes db_cart_items_with_user_id(Db* db, CartItemVec* vec, int64_t user_id) {
+    static_assert(sizeof(Cart) == 16, "model has changed");
+    static_assert(sizeof(CartItem) == 32, "model has changed");
+
+    sqlite3* connection;
+    CONNECT;
+    DbRes res;
+
+    sqlite3_stmt* stmt;
+    int sqlite_res = sqlite3_prepare_v2(connection,
+        "SELECT id "
+        " FROM carts WHERE user = ?",
+        -1, &stmt, NULL);
+    if (sqlite_res != SQLITE_OK) {
+        fprintf(stderr, "error: %s\n  at %s:%d\n", sqlite3_errmsg(connection),
+            __func__, __LINE__);
+        res = DbRes_Error;
+        goto l0_return;
+    }
+    sqlite3_bind_int64(stmt, 1, user_id);
+
+    int step_res = sqlite3_step(stmt);
+    if (step_res == SQLITE_DONE) {
+        res = DbRes_NotFound;
+        goto l0_return;
+    } else if (step_res != SQLITE_ROW) {
+        fprintf(stderr, "error: %s\n", sqlite3_errmsg(connection));
+        res = DbRes_Error;
+        goto l0_return;
+    }
+    int64_t cart_id = GET_INT(0);
+
+    sqlite_res = sqlite3_prepare_v2(
+        connection, "SELECT id, cart, product, amount FROM cart_items WHERE cart = ?", -1, &stmt, NULL);
+    sqlite3_bind_int64(stmt, 1, cart_id);
+
+    while ((sqlite_res = sqlite3_step(stmt)) == SQLITE_ROW) {
+        CartItem cart_item = {
+            .id = GET_INT(0),
+            .cart_id = GET_INT(1),
+            .product_id = GET_INT(2),
+            .amount = GET_INT(3),
+        };
+        cart_item_vec_push(vec, cart_item);
+    }
+    if (sqlite_res != SQLITE_DONE) {
+        fprintf(stderr, "error: %s\n", sqlite3_errmsg(connection));
+        res = DbRes_Error;
+        goto l0_return;
+    }
+
+    res = DbRes_Ok;
+l0_return:
+    if (stmt)
+        sqlite3_finalize(stmt);
+    DISCONNECT;
+    return res;
+
+}
+

backend/src/main.c

@@ -43,6 +43,8 @@ int main(void)
 
     http_server_get(server, "/api/products/all", route_get_products_all);
 
+    http_server_get(server, "/api/cart", route_get_cart_items_from_session);
+
     http_server_post(server, "/api/users/register", route_post_users_register);
     http_server_post(server, "/api/sessions/login", route_post_sessions_login);
     http_server_post(

backend/src/models.c

@@ -47,7 +47,7 @@ void cart_destroy(Cart* m)
 
 void cart_item_destroy(CartItem* m)
 {
-    static_assert(sizeof(CartItem) == 24, "model has changed");
+    static_assert(sizeof(CartItem) == 32, "model has changed");
 
     (void)m;
 }
@@ -170,7 +170,7 @@ char* cart_to_json_string(const Cart* m)
 
 char* cart_item_to_json_string(const CartItem* m)
 {
-    static_assert(sizeof(CartItem) == 24, "model has changed");
+    static_assert(sizeof(CartItem) == 32, "model has changed");
 
     String string;
     string_construct(&string);
@@ -178,9 +178,10 @@ char* cart_item_to_json_string(const CartItem* m)
         "{"
         "\"id\":%ld,"
         "\"cart_id\":%ld,"
+        "\"product_id\":%ld,"
         "\"amount\":%ld"
         "}",
-        m->id, m->cart_id, m->amount);
+        m->id, m->cart_id, m->product_id, m->amount);
 
     char* result = string_copy(&string);
     string_destroy(&string);
@@ -354,11 +355,12 @@ int cart_from_json(Cart* m, const JsonValue* json)
 
 int cart_item_from_json(CartItem* m, const JsonValue* json)
 {
-    static_assert(sizeof(CartItem) == 24, "model has changed");
+    static_assert(sizeof(CartItem) == 32, "model has changed");
 
     ObjField fields[] = {
         { "id", JsonType_Number },
         { "cart_id", JsonType_Number },
+        { "product_id", JsonType_Number },
         { "amount", JsonType_Number },
     };
     if (!obj_conforms(json, fields, sizeof(fields) / sizeof(fields[0])))
@@ -366,6 +368,7 @@ int cart_item_from_json(CartItem* m, const JsonValue* json)
     *m = (CartItem) {
         .id = GET_INT("id"),
         .cart_id = GET_INT("cart_id"),
+        .product_id = GET_INT("product_id"),
         .amount = GET_INT("amount"),
     };
     return 0;

backend/src/models.h

@@ -39,6 +39,7 @@ typedef struct {
 typedef struct {
     int64_t id;
     int64_t cart_id;
+    int64_t product_id;
     int64_t amount;
 } CartItem;