Tasks endpoint

package.json

@@ -26,6 +26,7 @@
     "express": "^4.17.1",
     "express-pino-logger": "^4.0.0",
     "graphql": "^14.5.7",
+    "graphql-tools": "^4.0.5",
     "helmet": "^3.21.1",
     "http-errors": "^1.7.3",
     "luxon": "^1.19.2",

sql/tasks/count.sql

@@ -0,0 +1 @@
+SELECT count(*) c FROM "tasks" WHERE owner = $1;

sql/tasks/hasNext.sql

@@ -0,0 +1 @@
+SELECT COUNT(*) > 0 r FROM "tasks" WHERE owner = $1 AND "id" > $2;

sql/tasks/hasPrev.sql

@@ -0,0 +1 @@
+SELECT COUNT(*) > 0 r FROM "tasks" WHERE owner = $1 AND "id" < $2;

sql/tasks/list.sql

@@ -9,6 +9,6 @@ SELECT
 FROM
     tasks
 WHERE
-    owner = $1
+    owner = $1 AND ($2 IS NULL OR id > $2) AND ($3 IS NULL OR id < $3)
 ORDER BY created_at ASC
-LIMIT $2 OFFSET $3;
+LIMIT $4;

sql/tasks/listReverse.sql

@@ -0,0 +1,14 @@
+SELECT 
+    id,
+    name,
+    notes,
+    schedule,
+    min_frequency,
+    max_frequency,
+    created_at
+FROM
+    tasks
+WHERE
+    owner = $1 AND ($2 IS NULL OR id > $2) AND ($3 IS NULL OR id < $3)
+ORDER BY created_at DESC
+LIMIT $4;

src/api.ts

@@ -1,127 +0,0 @@
-// Copyright (C) 2019 ModZero <modzero@modzero.xyz>
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Affero General Public License as
-// published by the Free Software Foundation, either version 3 of the
-// License, or (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Affero General Public License for more details.
-//
-// You should have received a copy of the GNU Affero General Public License
-// along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-import { db } from "@kredens/db";
-import { User } from "@kredens/db/models";
-import { ApolloServer, AuthenticationError, gql } from "apollo-server-express";
-import { Kind } from "graphql/language";
-import { GraphQLScalarType, GraphQLScalarTypeConfig } from "graphql/type";
-import { DateTime } from "luxon";
-
-const typeDefs = gql`
-  type Query {
-    "A simple type for getting started"
-    hello: String
-    migrations: [Migration]!
-    user(id: ID): User
-  }
-
-  type Migration {
-    id: ID!
-    name: String!
-    applied_at: DateTime!
-  }
-
-  type User {
-    id: ID!
-    email: String!
-    tasks: [Task]!
-  }
-
-  type Task {
-    id: ID
-    name: String!
-    notes: String
-    schedule: ScheduleType!
-    min_frequency: Int
-    max_frequency: Int
-    created_at: DateTime!
-  }
-
-  scalar DateTime
-
-  enum ScheduleType {
-    ONCE
-    DAILY
-    WEEKLY
-    MONTHLY
-    YEARLY
-  }
-`;
-
-const dateTimeConfig: GraphQLScalarTypeConfig<DateTime, string> = {
-  description: "Date custom scalar type",
-  name: "DateTime",
-  parseValue(value) {
-    return DateTime.fromISO(value as string);
-  },
-  serialize(value) {
-    return (value as DateTime).toISO();
-  },
-  parseLiteral(ast) {
-    if (ast.kind === Kind.STRING) {
-      return DateTime.fromISO(ast.value);
-    }
-
-    return null;
-  }
-};
-
-const resolvers = {
-  DateTime: new GraphQLScalarType(dateTimeConfig),
-  Query: {
-    hello: () => `Hello, world!`,
-    migrations: () => db.migrations.applied(),
-    user: async (
-      parent: any,
-      { id }: { id: string },
-      context: { user?: User }
-    ) => {
-      if (!context.user || context.user.id !== +id) {
-        throw new AuthenticationError(
-          "You cannot query users other than yourself"
-        );
-      }
-      return db.users.details(+id).then(user => user.orNull());
-    }
-  },
-  User: {
-    tasks: (user: User) =>
-      db.tasks.list(user.id).then(tasks =>
-        tasks.map(t => ({
-          ...t,
-          schedule: t.schedule.toUpperCase()
-        }))
-      )
-  }
-};
-
-export function server() {
-  return new ApolloServer({
-    context: async req => {
-      const user = req.req.user;
-
-      if (!user) {
-        throw new AuthenticationError("you must be logged in");
-      }
-
-      return {
-        user
-      };
-    },
-    resolvers,
-    typeDefs
-  });
-}

src/api/index.ts

@@ -0,0 +1,36 @@
+// Copyright (C) 2019 ModZero <modzero@modzero.xyz>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import resolvers from "@kredens/api/resolvers";
+import typeDefs from "@kredens/api/typeDefs";
+import { ApolloServer, AuthenticationError } from "apollo-server-express";
+
+export function server() {
+  return new ApolloServer({
+    context: async req => {
+      const user = req.req.user;
+
+      if (!user) {
+        throw new AuthenticationError("you must be logged in");
+      }
+
+      return {
+        user
+      };
+    },
+    resolvers,
+    typeDefs
+  });
+}

src/api/resolvers.ts

@@ -0,0 +1,226 @@
+// Copyright (C) 2019 ModZero <modzero@modzero.xyz>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import { db } from "@kredens/db";
+import * as models from "@kredens/db/models";
+import { IResolvers } from "graphql-tools";
+import { Kind } from "graphql/language";
+import { GraphQLScalarType, GraphQLScalarTypeConfig } from "graphql/type";
+import { DateTime } from "luxon";
+import { Maybe } from "monet";
+
+const dateTimeConfig: GraphQLScalarTypeConfig<DateTime, string> = {
+  name: "DateTime",
+  description: "Date custom scalar type",
+  serialize(value) {
+    return (value as DateTime).toISO();
+  },
+  parseValue(value) {
+    return DateTime.fromISO(value as string);
+  },
+  parseLiteral(ast) {
+    if (ast.kind === Kind.STRING) {
+      return DateTime.fromISO(ast.value);
+    }
+
+    return null;
+  }
+};
+
+interface Context {
+  user?: models.User;
+}
+
+interface Node {
+  ID: string;
+}
+
+interface User extends Node {
+  email?: string;
+  tasks?: Connection<Task>;
+}
+
+type ScheduleType = "ONCE" | "DAILY" | "WEEKLY" | "MONTHLY" | "YEARLY";
+
+interface Task extends Node {
+  name: string;
+  notes?: string;
+  schedule: ScheduleType;
+  minFrequency?: number;
+  maxFrequency?: number;
+  createdAt: DateTime;
+}
+
+interface PaginationArguments {
+  after?: string;
+  first?: number;
+  before?: string;
+  last?: number;
+}
+
+interface PageInfo {
+  hasNextPage: boolean;
+  hasPrevPage: boolean;
+  startCursor?: string;
+  endCursor?: string;
+}
+
+interface Edge<T extends Node> {
+  cursor: string;
+  node?: T;
+}
+
+interface Connection<T extends Node> {
+  edges?: Array<Edge<T>>;
+  pageInfo: PageInfo;
+}
+
+enum NodeKind {
+  User = "USER",
+  Task = "TASK"
+}
+
+const nodeKindFrom = (kind: string) => {
+  const keys = Object.keys(NodeKind).filter(x => NodeKind[x] === kind);
+  return keys.length > 0
+    ? Maybe.some<NodeKind>(NodeKind[keys[0]])
+    : Maybe.none<NodeKind>();
+};
+
+interface ID {
+  kind: NodeKind;
+  id: number;
+}
+
+const getId = (id: string) => {
+  const [kindStr, idStr] = Buffer.from(id, "base64")
+    .toString()
+    .split(":");
+  const kind = nodeKindFrom(kindStr);
+
+  return kind.flatMap<ID>(k => {
+    const actualId = parseInt(idStr, 10);
+
+    return isNaN(actualId)
+      ? Maybe.none()
+      : Maybe.some({ id: actualId, kind: k });
+  });
+};
+
+const getIdOfKind = (id: string, kind: NodeKind) =>
+  getId(id).filter(i => i.kind === kind);
+
+const buildId = (kind: NodeKind, id: number) =>
+  Buffer.from(`${kind}:${id}`).toString("base64");
+
+const scheduleTypeMap: { [id: string]: ScheduleType } = {
+  [models.ScheduleType.Once]: "ONCE",
+  [models.ScheduleType.Daily]: "DAILY",
+  [models.ScheduleType.Weekly]: "WEEKLY",
+  [models.ScheduleType.Monthly]: "MONTHLY",
+  [models.ScheduleType.Yearly]: "YEARLY"
+};
+
+async function userTasks(
+  user: { id: string },
+  args: PaginationArguments
+): Promise<Connection<Task>> {
+  return db.task<Connection<Task>>(async t => {
+    const after =
+      args.after &&
+      Maybe.some(args.before)
+        .flatMap(id => getIdOfKind(id, NodeKind.Task))
+        .some().id;
+    const before =
+      args.before &&
+      Maybe.fromFalsy(args.before)
+        .flatMap(id => getIdOfKind(id, NodeKind.Task))
+        .some().id;
+    const userId = getId(user.id).some().id;
+
+    let rows =
+      args.first || !(args.first || args.last)
+        ? await t.tasks.list(userId, args.first, after, before)
+        : (await t.tasks.listReverse(
+            userId,
+            args.last,
+            after,
+            before
+          )).reverse();
+
+    if (args.first && args.last) {
+      rows = rows.slice(-1 * args.last);
+    }
+
+    return {
+      edges: rows.map(row => ({
+        cursor: buildId(NodeKind.Task, row.id),
+        node: {
+          ID: buildId(NodeKind.Task, row.id),
+          createdAt: row.createdAt,
+          maxFrequency: row.maxFrequency,
+          minFrequency: row.minFrequency,
+          name: row.name,
+          notes: row.notes,
+          schedule: scheduleTypeMap[row.schedule]
+        }
+      })),
+      pageInfo: {
+        hasNextPage:
+          rows.length > 0 ? await t.tasks.hasNext(userId, rows[0].id) : false,
+        hasPrevPage:
+          rows.length > 0
+            ? await t.tasks.hasPrev(userId, rows[rows.length - 1].id)
+            : false,
+        startCursor:
+          rows.length > 0 ? buildId(NodeKind.Task, rows[0].id) : null,
+        endCursor:
+          rows.length > 0
+            ? buildId(NodeKind.Task, rows[rows.length - 1].id)
+            : null
+      }
+    };
+  });
+}
+
+const resolvers: IResolvers<any, Context> = {
+  DateTime: new GraphQLScalarType(dateTimeConfig),
+  Query: {
+    hello: () => `Hello, world!`,
+    migrations: () => db.migrations.applied(),
+    user: async (parent: any, { id }: { id?: string }, context) =>
+      Maybe.fromFalsy(id)
+        .orElse(Maybe.some(buildId(NodeKind.User, context.user.id)))
+        .flatMap(i => getId(i))
+        .filter(i => i.kind === NodeKind.User)
+        .filter(i => i.id === context.user.id)
+        .map(i =>
+          db.users.details(i.id).then(user =>
+            user
+              .map(u => ({
+                email: u.email,
+                id: buildId(NodeKind.User, u.id)
+              }))
+              .orNull()
+          )
+        )
+        .orNull()
+  },
+  User: {
+    tasks: userTasks
+  }
+};
+
+export default resolvers;

src/api/typeDefs.ts

@@ -0,0 +1,79 @@
+// Copyright (C) 2019 ModZero <modzero@modzero.xyz>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import { gql } from "apollo-server-express";
+
+export default gql`
+  type Query {
+    "A simple type for getting started"
+    node(id: ID!): Node
+    hello: String
+    migrations: [Migration]!
+    user(id: ID): User
+  }
+
+  interface Node {
+    id: ID!
+  }
+
+  type Migration implements Node {
+    id: ID!
+    name: String!
+    appliedAt: DateTime!
+  }
+
+  type User implements Node {
+    id: ID!
+    email: String!
+    tasks(after: String, first: Int, before: String, last: Int): TaskConnection
+  }
+
+  type Task implements Node {
+    id: ID!
+    name: String!
+    notes: String
+    schedule: ScheduleType!
+    minFrequency: Int
+    maxFrequency: Int
+    createdAt: DateTime!
+  }
+
+  type TaskConnection {
+    edges: [TaskEdge]
+    pageInfo: PageInfo!
+  }
+
+  type TaskEdge {
+    cursor: String!
+    node: Task
+  }
+
+  type PageInfo {
+    hasNextPage: Boolean!
+    hasPrevPage: Boolean!
+    startCursor: String
+    endCursor: String
+  }
+
+  scalar DateTime
+
+  enum ScheduleType {
+    ONCE
+    DAILY
+    WEEKLY
+    MONTHLY
+    YEARLY
+  }
+`;

src/db/models.ts

@@ -18,7 +18,7 @@ import { DateTime } from "luxon";
 export interface Migration {
   id: number;
   name: string;
-  applied_at: DateTime;
+  appliedAt: DateTime;
 }
 
 export interface User {
@@ -26,7 +26,13 @@ export interface User {
   email: string;
 }
 
-export type ScheduleType = "once" | "daily" | "weekly" | "monthly" | "yearly";
+export enum ScheduleType {
+  Once = "once",
+  Daily = "daily",
+  Weekly = "weekly",
+  Monthly = "monthly",
+  Yearly = "yearly"
+}
 
 export interface Task {
   id: number;
@@ -34,9 +40,9 @@ export interface Task {
   name: string;
   notes?: string;
   schedule: ScheduleType;
-  min_frequency?: number;
-  max_frequency?: number;
-  created_at: DateTime;
+  minFrequency?: number;
+  maxFrequency?: number;
+  createdAt: DateTime;
 }
 
 export interface Session {

src/db/repos/migrations.ts

@@ -48,12 +48,10 @@ export class MigrationRepository {
   }
 
   public async applied(): Promise<Migration[]> {
-    return this.db.map<Migration>(sql.applied, [], row => {
-      return {
-        applied_at: row.applied_at as DateTime,
-        id: +row.id,
-        name: row.name
-      };
-    });
+    return this.db.map(sql.applied, [], row => ({
+      appliedAt: row.applied_at as DateTime,
+      id: +row.id,
+      name: row.name
+    }));
   }
 }

src/db/repos/tasks.ts

@@ -17,6 +17,19 @@ import { ScheduleType, Task } from "@kredens/db/models";
 import { tasks as sql } from "@kredens/db/sql";
 import { IDatabase, IMain } from "pg-promise";
 
+function rowToTask(row: any): Task {
+  return {
+    createdAt: row.created_at,
+    id: +row.id,
+    maxFrequency: +row.maxFrequency,
+    minFrequency: +row.minFrequency,
+    name: row.name,
+    notes: row.notes,
+    owner: +row.owner,
+    schedule: row.schedule as ScheduleType
+  };
+}
+
 export class TaskRepository {
   private db: IDatabase<any>;
 
@@ -24,9 +37,33 @@ export class TaskRepository {
     this.db = db;
   }
 
-  public async list(owner: number): Promise<Task[]> {
-    return this.db
-      .manyOrNone<Task>(sql.list, [owner, 10, 0])
-      .then(rows => (rows ? rows : []));
+  public async list(
+    owner: number,
+    limit?: number,
+    after?: number,
+    before?: number
+  ): Promise<Task[]> {
+    return this.db.map(sql.list, [owner, after, before, limit || 10], row =>
+      rowToTask(row)
+    );
+  }
+
+  public async listReverse(
+    owner: number,
+    limit?: number,
+    after?: number,
+    before?: number
+  ): Promise<Task[]> {
+    return this.db.map(sql.list, [owner, after, before, limit || 10], row =>
+      rowToTask(row)
+    );
+  }
+
+  public async hasNext(owner: number, after: number): Promise<boolean> {
+    return this.db.one(sql.hasNext, [owner, after]).then(row => row.r);
+  }
+
+  public async hasPrev(owner: number, before: number): Promise<boolean> {
+    return this.db.one(sql.hasPrev, [owner, before]).then(row => row.r);
   }
 }

src/db/sql/index.ts

@@ -42,7 +42,11 @@ const users = {
 };
 
 const tasks = {
-  list: sql("tasks/list.sql")
+  count: sql("tasks/count.sql"),
+  hasNext: sql("tasks/hasNext.sql"),
+  hasPrev: sql("tasks/hasPrev.sql"),
+  list: sql("tasks/list.sql"),
+  listReverse: sql("tasks/listReverse.sql")
 };
 
 const sessions = {

tslint.json

@@ -11,7 +11,8 @@
             "vue-loader/lib/plugin",
             "@kredens"
         ],
-        "no-implicit-dependencies": [true, ["@kredens"]]
+        "no-implicit-dependencies": [true, ["@kredens"]],
+        "object-literal-sort-keys": [true, "match-declaration-order-only", "shorthand-first"]
     },
     "rulesDirectory": []
 }