Add crud example file

examples/crud_operations.js

@@ -0,0 +1,108 @@
+// Licensed under the Apache License, Version 2.0 (the 'License'); you may not
+// use this file except in compliance with the License. You may obtain a copy of
+// the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an 'AS IS' BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations under
+// the License.
+
+myRepository = {};
+
+createDatabaseConnection = async () => {
+    // connect to server
+    const server = require('nano')('http://your-username:your-password@localhost:5984');
+    // connect to database
+    return await server.db.use('your-database');
+}
+
+myRepository.getAll = async () => {
+    try {
+        const db = await createDatabaseConnection();
+        const response = await db.find({ selector: {}});
+        return response.docs;
+    } catch (err) {
+        console.error(err);
+    }
+};
+
+myRepository.get = async (id) => {
+    try {
+        const db = await createDatabaseConnection();
+        const response = await db.get(id);
+        return response;
+    } catch (err) {
+        console.error(err);
+        return null;
+    }
+};
+
+myRepository.insert = async (id, document) => {
+    try {
+        const db = await createDatabaseConnection();
+        const response = await db.insert(document, id);
+        return response.ok;
+    } catch (err) {
+        console.error(err);
+        return false;
+    }
+};
+
+myRepository.update = async (id, newDocument) => {
+    try {
+        const db = await createDatabaseConnection();
+        const existingDocument = await db.get(id);
+        if (existingDocument) {
+            // If you need to update a document then you should just insert again (but specifying the revision you are updating)
+            newDocument["_rev"] = existingDocument["_rev"];
+            const response = await db.insert(newDocument, id);
+            return response.ok;
+        }
+    } catch (err) {
+        console.error(err);
+        return false;
+    }
+};
+
+myRepository.delete = async (id) => {
+    try {
+        const db = await createDatabaseConnection();
+        const existingDocument = await db.get(id);
+        const response = await db.destroy(id, existingDocument["_rev"]);
+        return response.ok;
+    } catch (err) {
+        console.error(err);
+        return false;
+    }
+};
+
+
+// Test repository calls
+(async() => {
+    console.log("---  First insert  ---");
+    const insertResult = await myRepository.insert("my-document-1", { "someField": "Hello"});
+    console.log(insertResult);
+
+    console.log("--- Delete ---");
+    const deleteResult = await myRepository.delete("my-document-1");
+    console.log(deleteResult);
+
+    console.log("---  Second insert ---");
+    const anotherInsertResult = await myRepository.insert("my-document-2", { "someField": "Hello"});
+    console.log(anotherInsertResult);
+
+    console.log("---  Update ---");
+    const updateResult = await myRepository.update("my-document-2", { "someField": "Hello there!"});
+    console.log(updateResult);
+
+    console.log("---  Get All ---");
+    const resultAll = await myRepository.getAll();
+    console.log(resultAll);
+
+    console.log("---  Get By Id ---");
+    const result = await myRepository.get("my-document-2");
+    console.log(result);
+})();