Merge pull request #2 from ponsoc/Update-readme-and-example-configuration

Update readme and example configuration

Author: ponsoc

README.md

@@ -21,7 +21,7 @@ To change the configuration edit the `config/tables.js` file. The configuration
     - `REAL NOT NULL`
     - `TEXT UNIQUE NOT NULL`
     - `TEXT DEFAULT 'Hello' CHECK(columnName <> 'World')`
-    - `FOREIGN KEY(columnName) REFERENCES tableName(columnName)`. Use this format to create a foreign key constraint. Omit the `name` property when using this format. Add `FOREIGN KEY` constraints to the end of the table definition. Note that the field itself still needs to be added to the table definition. Make sure to order the tables in the configuration so that the referenced table is created first.
+    - `FOREIGN KEY(columnName) REFERENCES tableName(columnName)`. Use this format to create a foreign key constraint. Omit the `name` property when using this format. Add `FOREIGN KEY` constraints to the end of the table definition. Note that the field itself (where the foreign key refers to) still needs to be added to the table definition. Make sure to order the tables in the configuration so that the referenced table is created first.
 
   - `generator`: A function with the signature `(variables, row) -> value`. The function is evaluated for each row generated. The variables contains the variables defined in the table configuration. The row contains the row data when generating rows based on the source table.
 
@@ -87,7 +87,6 @@ To enable debugging set the `DEBUG` environment variable to `sqlite-data-generat
 
 ## Roadmap
 
-- Extend the example configuration to include more complex examples
 - Add the ability to generate multiple rows of data for a single row in the source table
 
 ## Known Issues

package.json

@@ -1,6 +1,6 @@
 {
   "name": "sqlite-data-generator",
-  "version": "1.0.1",
+  "version": "1.0.2",
   "description": "A CLI for generating SQLite database files with example data",
   "main": "src/app.js",
   "scripts": {

src/app.js

@@ -1,8 +1,9 @@
 const { faker } = require("@faker-js/faker");
 const SQLiteDataGenerator = require("./lib/SQLiteDataGenerator");
 
+const db_name = "example.db"
 // create a new instance of the SQLiteLib class
-const db = new SQLiteDataGenerator("example.db");
+const db = new SQLiteDataGenerator();
 // import the TableConfig and pass any dependencies
 const tables = require("./config/tables.js")({ faker, db });
 
@@ -11,6 +12,7 @@ async function main() {
     await db.connect();
     await db.enableForeignKeySupport();
     await db.generate(tables);
+    await db.writeToFile(db_name);
   } catch (error) {
     throw error;
   } finally {
@@ -22,4 +24,4 @@ main()
   .then(() => console.log("Database generated successfully!"))
   .catch((error) => console.error(error));
 
-module.exports = { SQLiteDataGenerator };
+module.exports = { SQLiteDataGenerator };

src/config/tables.js

@@ -2,20 +2,34 @@ module.exports = function (dependencies) {
   return [
     {
       name: "users",
+      rowVars: {
+        name: () => dependencies.faker.person.fullName(),
+      },
       fields: [
         { name: "id", type: "INTEGER PRIMARY KEY" },
-        { name: "name", type: "TEXT", generator: () => dependencies.faker.person.fullName() },
-        { name: "email", type: "TEXT", generator: () => dependencies.faker.internet.email() },
+        { name: "name", type: "TEXT", generator: (variables) => variables.row.name },
+        { name: "email", type: "TEXT", generator: (variables) => variables.row.name.replaceAll(/\s/g, "").toLowerCase() + "@example.com" },
         { name: "age", type: "INTEGER", generator: () => dependencies.faker.number.int({ min: 18, max: 90 }) },
       ],
-      rows: 10,
+      rows: 8,
     },
     {
       name: "posts",
+      rowVars: {
+        state: () => dependencies.faker.helpers.arrayElement(["draf", "review","published"]),
+      },
       fields: [
         { name: "id", type: "INTEGER PRIMARY KEY" },
         { name: "title", type: "TEXT", generator: () => dependencies.faker.lorem.words(3) },
         { name: "content", type: "TEXT", generator: () => dependencies.faker.lorem.paragraph() },
+        { name: "created_at", type: "TEXT", generator: () => dependencies.faker.date.past().toISOString() },
+        {name: "published_at", type: "TEXT", generator: (variables) => {
+          if (variables.row.state === "published") {
+            return dependencies.faker.date.past().toISOString()
+          }
+          return ""
+        },
+      },
         {
           name: "author_id",
           type: "INTEGER",
@@ -30,5 +44,50 @@ module.exports = function (dependencies) {
       ],
       rows: 20,
     },
+    {
+      name: "post_versions",
+      rowVars: {
+        object_id: async () => {
+          const row = await dependencies.db.getRandomRowFromTable("posts");
+          return row.id;
+        },
+      },
+      fields: [
+        { name: "id", type: "INTEGER PRIMARY KEY" },
+        {
+          name: "object_id",
+          type: "INTEGER",
+          generator: async (variables) => variables.row.object_id,
+        },
+        {
+          name: "version",
+          type: "INTEGER",
+          generator: async (variables) => {
+            const row = await dependencies.db.getRowFromTable("post_versions", `object_id = ${variables.row.object_id}`, `version DESC`);
+            return row ? row.version + 1 : 1;
+          },
+        },
+        {
+          name: "created_at",
+          type: "TEXT",
+          generator: async (variables) => {
+            const versionRow = await dependencies.db.getRowFromTable(
+              "post_versions",
+              `object_id = ${variables.row.object_id}`,
+              `version DESC`
+            );
+            if (versionRow) {
+              return dependencies.faker.date.between({ from: versionRow.created_at, to: new Date() }).toISOString();
+            }
+            const objectRow = await dependencies.db.getRowFromTable("posts", `id = ${variables.row.object_id}`);
+            return objectRow.created_at;
+          },
+        },
+        {
+          type: "FOREIGN KEY(object_id) REFERENCES posts(id)",
+        },
+      ],
+      rows: 35,
+    },
   ];
 };

src/lib/SQLiteDataGenerator.js

@@ -5,9 +5,11 @@ class SQLiteDataGenerator {
    * @param {string} database - The path to the SQLite database file.
    * @param {object} sqlite3 - The SQLite3 module.
    */
-  constructor(database, sqlite3 = require("sqlite3").verbose(), debug = require("debug")("sqlite-data-generator")) {
+  constructor(fs = require("fs"), sqlite3 = require("sqlite3").verbose(), debug = require("debug")("sqlite-data-generator")) {
+    this.temp_db_name = "sqlite_data_generator.db"
+    this.fs = fs
     this.sqlite3 = sqlite3;
-    this.db = new sqlite3.Database(database);
+    this.db = new sqlite3.Database(this.temp_db_name);
     this.debug = debug;
   }
 
@@ -47,12 +49,22 @@ class SQLiteDataGenerator {
         if (err) {
           reject(new Error(`Error closing the database connection: ${err.message}`));
         } else {
+          this.fs.unlinkSync(this.temp_db_name)
           resolve();
         }
       });
     });
   }
 
+  /**
+   * Writes the temporary database to the final location
+   * @returns {void} 
+   */
+  async writeToFile(db_name) {
+    this.fs.copyFileSync(this.temp_db_name, db_name)
+  }
+
+
   /**
    * Generates SQLite data for the given tables.
    *
@@ -101,7 +113,7 @@ class SQLiteDataGenerator {
           }
         });
       } else {
-        resolve(null);
+        reject(new Error(`Error getting row from table ${tableName}: Table doesn't exists.`));
       }
     });
   }