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DSE_Application_Development_Prepared_Statements.studio-nb.tar
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notebook.bin 0100644 0000000 0000000 00000056765 13355211672 012147 0 ustar 00 0000000 0000000 json_notebook_v1 {"1":"bed65194-59a9-457f-b98f-849c2fd1df2c","10":"e3111e9b-0a01-4111-a584-a2ab859e15c6","11":"DSE Application Development: Prepared Statements","12":{"1":1538470281,"2":520000000},"13":{"1":1538590698,"2":587000000},"14":false,"15":[{"1":"d5ebd65b-2806-4610-b016-02efe406426b","10":4,"11":"<center>![Solution Day Banner](https://s3.amazonaws.com/datastaxtraining/solution-days/cassandra-intro/DevDayBanner.png \"Developer Day Banner\" )</center>","12":"markdown","13":{"1":"1cb5fe7f-537f-4aa8-8dfc-4a7971ad04ea","10":{"9":"<p><center><img src=\"https://s3.amazonaws.com/datastaxtraining/solution-days/cassandra-intro/DevDayBanner.png\" alt=\"Solution Day Banner\" title=\"Developer Day Banner\" /></center></p>\n"},"11":4,"12":false},"15":5,"16":true,"17":true,"18":{},"25":"CL.ONE"},{"1":"b86ebb37-b7e9-49a2-a510-938aa4779466","10":4,"11":"In this exercise, you will add the code to the KillrVideo application to insert a new user. First, open your web-based Eclipse editor by visiting the url: `http://<your-che-node-IP-address>:8080/dashboard/#/ide/che/killrvideo`.\n\n![Eclipse Che](https://s3.amazonaws.com/datastaxtraining/developer-day/app-dev/eclipse-che.png \"Eclipse Che\" )","12":"markdown","13":{"1":"1404bebc-2d5e-4032-8a27-9f1ceb445035","10":{"9":"<p>In this exercise, you will add the code to the KillrVideo application to insert a new user. First, open your web-based Eclipse editor by visiting the url: <code>http://<your-che-node-IP-address>:8080/dashboard/#/ide/che/killrvideo</code>.</p>\n<p><img src=\"https://s3.amazonaws.com/datastaxtraining/developer-day/app-dev/eclipse-che.png\" alt=\"Eclipse Che\" title=\"Eclipse Che\" /></p>\n"},"11":4,"12":false},"16":true,"17":true,"18":{},"25":"CL.ONE"},{"1":"bf3f3bb8-70cc-4087-a259-001a2db05fb7","10":4,"11":"Run the application by pressing the blue execute arrow at the top or by using the keyboard shortcut `ALT-R` (or `COMMAND-R` on Mac).\n\n<center>![Starting the Application](https://s3.amazonaws.com/datastaxtraining/developer-day/app-dev/start-application.PNG \"Starting the Application\" )</center>\n\nOnce the application is running, navigate to `http://<your-web-node-ip-address>:3000`, and notice the webpage loads.\n\n<center>![KillrVideo Page](https://s3.amazonaws.com/datastaxtraining/developer-day/app-dev/killrvideo-page.PNG \"KillrVideo Page\" )</center>\n\nGo ahead and follow the steps to create a new user by clicking on the green `REGISTER` button to the upper right.\n\n<center>![Register Button](https://s3.amazonaws.com/datastaxtraining/developer-day/app-dev/register-button.PNG \"Register Button\" )</center>\n\n<center>![Registration Info](https://s3.amazonaws.com/datastaxtraining/developer-day/app-dev/registration-info.PNG \"Registration Info\" )</center>\n\nNotice the registration is broken, and the button just hangs indefinitely. WAH WAHHHH.\n\n<center>![Busted Regisration](https://s3.amazonaws.com/datastaxtraining/developer-day/app-dev/busted-registratation.PNG \"Busted Registration\" )</center>","12":"markdown","13":{"1":"ffcdca43-320a-4921-a3bb-817a071bd885","10":{"9":"<p>Run the application by pressing the blue execute arrow at the top or by using the keyboard shortcut <code>ALT-R</code> (or <code>COMMAND-R</code> on Mac).</p>\n<p><center><img src=\"https://s3.amazonaws.com/datastaxtraining/developer-day/app-dev/start-application.PNG\" alt=\"Starting the Application\" title=\"Starting the Application\" /></center></p>\n<p>Once the application is running, navigate to <code>http://<your-web-node-ip-address>:3000</code>, and notice the webpage loads.</p>\n<p><center><img src=\"https://s3.amazonaws.com/datastaxtraining/developer-day/app-dev/killrvideo-page.PNG\" alt=\"KillrVideo Page\" title=\"KillrVideo Page\" /></center></p>\n<p>Go ahead and follow the steps to create a new user by clicking on the green <code>REGISTER</code> button to the upper right.</p>\n<p><center><img src=\"https://s3.amazonaws.com/datastaxtraining/developer-day/app-dev/register-button.PNG\" alt=\"Register Button\" title=\"Register Button\" /></center></p>\n<p><center><img src=\"https://s3.amazonaws.com/datastaxtraining/developer-day/app-dev/registration-info.PNG\" alt=\"Registration Info\" title=\"Registration Info\" /></center></p>\n<p>Notice the registration is broken, and the button just hangs indefinitely. WAH WAHHHH.</p>\n<p><center><img src=\"https://s3.amazonaws.com/datastaxtraining/developer-day/app-dev/busted-registratation.PNG\" alt=\"Busted Regisration\" title=\"Busted Registration\" /></center></p>\n"},"11":4,"12":false},"16":true,"17":true,"18":{},"25":"CL.ONE"},{"1":"95d94daf-f2fc-47af-814e-4bebcd3d316a","10":4,"11":"Your mission, should you choose to accept it, is to make the user sign-on process work. No stress. We will take you through it. First off, in your Eclipse Che `killrvideo` workspace, navigate to and open the file `/killrvideo-java/src/main/java/killrvideo/service/UserManagementService.java`.\n\n<center>![User Management Service File](https://s3.amazonaws.com/datastaxtraining/developer-day/app-dev/user-management-service.PNG \"User Management Service File\" )</center>\n\nFind the following comment:\n\n```\n // DECLARE THOSE FIELDS!\n```\n\nThe first fields we will declare are two prepared statments:\n\n1) Check that a user email doesn't already exist in the `user_credentials` table.\n2) Insert the full user information into the `users` table.\n\nCopy the following lines of code and paste them over the comment:\n\n```\n private PreparedStatement createUser_checkEmailPrepared;\n private PreparedStatement createUser_insertUserPrepared;\n```\n\nNotice both are a `PreparedStatement` which means the cluster will compile the statement distribute the statement once, and we can fill in the variables later. `PreparedStatements` are faster this way over using `SimpleStatements` which must compile and distribute the query every time.","12":"markdown","13":{"1":"16492075-d537-4a77-8a46-39a24cf2001a","10":{"9":"<p>Your mission, should you choose to accept it, is to make the user sign-on process work. No stress. We will take you through it. First off, in your Eclipse Che <code>killrvideo</code> workspace, navigate to and open the file <code>/killrvideo-java/src/main/java/killrvideo/service/UserManagementService.java</code>.</p>\n<p><center><img src=\"https://s3.amazonaws.com/datastaxtraining/developer-day/app-dev/user-management-service.PNG\" alt=\"User Management Service File\" title=\"User Management Service File\" /></center></p>\n<p>Find the following comment:</p>\n<pre><code> // DECLARE THOSE FIELDS!\n</code></pre>\n<p>The first fields we will declare are two prepared statments:</p>\n<p>1) Check that a user email doesn't already exist in the <code>user_credentials</code> table.\n<br />2) Insert the full user information into the <code>users</code> table.</p>\n<p>Copy the following lines of code and paste them over the comment:</p>\n<pre><code> private PreparedStatement createUser_checkEmailPrepared;\n private PreparedStatement createUser_insertUserPrepared;\n</code></pre>\n<p>Notice both are a <code>PreparedStatement</code> which means the cluster will compile the statement distribute the statement once, and we can fill in the variables later. <code>PreparedStatements</code> are faster this way over using <code>SimpleStatements</code> which must compile and distribute the query every time.</p>\n"},"11":4,"12":false},"16":true,"17":true,"18":{},"25":"CL.ONE"},{"1":"8a20b032-3aa9-4d80-a5d4-3dc2e18c0d2b","10":4,"11":"Now find the following comment in the same file:\n\n```\n // PREPARE THOSE STATEMENTS!\n```\n\nand replace it with the following code:\n\n```\n createUser_checkEmailPrepared = dseSession.prepare(\n QueryBuilder\n .insertInto(Schema.KEYSPACE, userCredentialsTableName)\n .value(\"email\", QueryBuilder.bindMarker())\n .value(\"password\", QueryBuilder.bindMarker())\n .value(\"userid\", QueryBuilder.bindMarker())\n .ifNotExists() // use lightweight transaction\n ).setConsistencyLevel(ConsistencyLevel.LOCAL_QUORUM);\n\n createUser_insertUserPrepared = dseSession.prepare(\n QueryBuilder\n .insertInto(Schema.KEYSPACE, usersTableName)\n .value(\"userid\", QueryBuilder.bindMarker())\n .value(\"firstname\", QueryBuilder.bindMarker())\n .value(\"lastname\", QueryBuilder.bindMarker())\n .value(\"email\", QueryBuilder.bindMarker())\n .value(\"created_date\", QueryBuilder.bindMarker())\n .ifNotExists() // use lightweight transaction\n ).setConsistencyLevel(ConsistencyLevel.LOCAL_QUORUM);\n```\n\nNotice we use `QueryBuilder` to draft up our query, placing `bindMarker()`s where the insert variables will later go. We also set the consistency level on both queries and a lightweight transaction to avoid duplicate users. `dseSession.prepare()` is where the compile-once-and-reuse magic happens. All we need to do now is `bind()` our prepared statement variables to actual values and `execute()` the result.","12":"markdown","13":{"1":"98a9f911-39db-48fe-b7e2-2944926fee47","10":{"9":"<p>Now find the following comment in the same file:</p>\n<pre><code> // PREPARE THOSE STATEMENTS!\n</code></pre>\n<p>and replace it with the following code:</p>\n<pre><code> createUser_checkEmailPrepared = dseSession.prepare(\n QueryBuilder\n .insertInto(Schema.KEYSPACE, userCredentialsTableName)\n .value(\"email\", QueryBuilder.bindMarker())\n .value(\"password\", QueryBuilder.bindMarker())\n .value(\"userid\", QueryBuilder.bindMarker())\n .ifNotExists() // use lightweight transaction\n ).setConsistencyLevel(ConsistencyLevel.LOCAL_QUORUM);\n\n createUser_insertUserPrepared = dseSession.prepare(\n QueryBuilder\n .insertInto(Schema.KEYSPACE, usersTableName)\n .value(\"userid\", QueryBuilder.bindMarker())\n .value(\"firstname\", QueryBuilder.bindMarker())\n .value(\"lastname\", QueryBuilder.bindMarker())\n .value(\"email\", QueryBuilder.bindMarker())\n .value(\"created_date\", QueryBuilder.bindMarker())\n .ifNotExists() // use lightweight transaction\n ).setConsistencyLevel(ConsistencyLevel.LOCAL_QUORUM);\n</code></pre>\n<p>Notice we use <code>QueryBuilder</code> to draft up our query, placing <code>bindMarker()</code>s where the insert variables will later go. We also set the consistency level on both queries and a lightweight transaction to avoid duplicate users. <code>dseSession.prepare()</code> is where the compile-once-and-reuse magic happens. All we need to do now is <code>bind()</code> our prepared statement variables to actual values and <code>execute()</code> the result.</p>\n"},"11":4,"12":false},"16":true,"17":true,"18":{},"25":"CL.ONE"},{"1":"82066d68-5024-401f-8788-0e02d6c5c5a7","10":4,"11":"Now find the following comment within that same file:\n\n```\n // CREATE THAT USER!\n```\n\nHere we will bind our variables and execute our insert.\n\nPaste the following code over that comment:\n\n```\n if (!validator.isValid(request, responseObserver)) {\n return;\n }\n\n```\n\nThis simply validates that the HTTP request is valid. Now add the following code below that:\n\n```\n final Date now = new Date();\n final CommonTypes.Uuid userIdUuid = request.getUserId();\n final UUID userIdUUID = UUID.fromString(userIdUuid.getValue());\n final String firstName = request.getFirstName();\n final String lastName = request.getLastName();\n\n final String hashedPassword = HashUtils.hashPassword(request.getPassword().trim());\n final String email = request.getEmail();\n final String dupUserMessaage = String.format(\"Exception creating user because it already exists with email %s\", email);\n```\nThis pulls the values we are interested out of the HTTP request.\n\nNow add the following:\n\n```\n final BoundStatement checkEmailQuery = createUser_checkEmailPrepared.bind()\n .setString(\"email\", email)\n .setString(\"password\", hashedPassword)\n .setUUID(\"userid\", userIdUUID);\n```\nThis binds our `createUser_checkEmailPrepared` prepared statment to actual values, making a `BoundStatement` that we can actually `execute()`.\n\nContinue adding:\n\n```\n ResultSet checkEmailResultSet = dseSession.execute(checkEmailQuery);\n if (!checkEmailResultSet.wasApplied()) {\n responseObserver.onError(Status.INVALID_ARGUMENT\n .augmentDescription(dupUserMessaage).asRuntimeException());\n responseObserver.onCompleted();\n return;\n }\n```\n\nHere we `execute()` our `BoundStatment` and further check that the insert `wasApplied()`. If not, we return an error.\n\nContinue adding code:\n```\n final BoundStatement insertUser = createUser_insertUserPrepared.bind()\n .setUUID(\"userid\", userIdUUID)\n .setString(\"firstname\", firstName)\n .setString(\"lastname\", lastName)\n .setString(\"email\", email)\n .setTimestamp(\"created_date\", now);\n\n ResultSet insertUserResultSet = dseSession.execute(insertUser);\n\n if(!insertUserResultSet.wasApplied()) {\n responseObserver.onError(Status.INVALID_ARGUMENT\n .augmentDescription(\"User ID not unique\").asRuntimeException());\n responseObserver.onCompleted();\n return;\n }\n\n```\nThis inserts the full user record into the `users` table. Again we check that the result applied.\n\nNow finish serving the HTTP request by adding the following:\n\n```\n responseObserver.onNext(CreateUserResponse.newBuilder().build());\n responseObserver.onCompleted();\n```","12":"markdown","13":{"1":"f9c071af-a409-451d-ace8-4946bdefd33f","10":{"9":"<p>Now find the following comment within that same file:</p>\n<pre><code> // CREATE THAT USER!\n</code></pre>\n<p>Here we will bind our variables and execute our insert.</p>\n<p>Paste the following code over that comment:</p>\n<pre><code> if (!validator.isValid(request, responseObserver)) {\n return;\n }\n</code></pre>\n<p>This simply validates that the HTTP request is valid. Now add the following code below that:</p>\n<pre><code> final Date now = new Date();\n final CommonTypes.Uuid userIdUuid = request.getUserId();\n final UUID userIdUUID = UUID.fromString(userIdUuid.getValue());\n final String firstName = request.getFirstName();\n final String lastName = request.getLastName();\n\n final String hashedPassword = HashUtils.hashPassword(request.getPassword().trim());\n final String email = request.getEmail();\n final String dupUserMessaage = String.format(\"Exception creating user because it already exists with email %s\", email);\n</code></pre>\n<p>This pulls the values we are interested out of the HTTP request.</p>\n<p>Now add the following:</p>\n<pre><code> final BoundStatement checkEmailQuery = createUser_checkEmailPrepared.bind()\n .setString(\"email\", email)\n .setString(\"password\", hashedPassword)\n .setUUID(\"userid\", userIdUUID);\n</code></pre>\n<p>This binds our <code>createUser_checkEmailPrepared</code> prepared statment to actual values, making a <code>BoundStatement</code> that we can actually <code>execute()</code>.</p>\n<p>Continue adding:</p>\n<pre><code> ResultSet checkEmailResultSet = dseSession.execute(checkEmailQuery);\n if (!checkEmailResultSet.wasApplied()) {\n responseObserver.onError(Status.INVALID_ARGUMENT\n .augmentDescription(dupUserMessaage).asRuntimeException());\n responseObserver.onCompleted();\n return;\n }\n</code></pre>\n<p>Here we <code>execute()</code> our <code>BoundStatment</code> and further check that the insert <code>wasApplied()</code>. If not, we return an error.</p>\n<p>Continue adding code:</p>\n<pre><code> final BoundStatement insertUser = createUser_insertUserPrepared.bind()\n .setUUID(\"userid\", userIdUUID)\n .setString(\"firstname\", firstName)\n .setString(\"lastname\", lastName)\n .setString(\"email\", email)\n .setTimestamp(\"created_date\", now);\n\n ResultSet insertUserResultSet = dseSession.execute(insertUser);\n\n if(!insertUserResultSet.wasApplied()) {\n responseObserver.onError(Status.INVALID_ARGUMENT\n .augmentDescription(\"User ID not unique\").asRuntimeException());\n responseObserver.onCompleted();\n return;\n }\n</code></pre>\n<p>This inserts the full user record into the <code>users</code> table. Again we check that the result applied.</p>\n<p>Now finish serving the HTTP request by adding the following:</p>\n<pre><code> responseObserver.onNext(CreateUserResponse.newBuilder().build());\n responseObserver.onCompleted();\n</code></pre>\n"},"11":4,"12":false},"16":true,"17":true,"18":{},"25":"CL.ONE"},{"1":"2319163c-2ec5-4b2a-b1dc-6da93324e98d","10":4,"11":"The entire `createUser()` function should look like so:\n\n```\n@Override\npublic void createUser(CreateUserRequest request, StreamObserver<CreateUserResponse> responseObserver) {\n if (!validator.isValid(request, responseObserver)) {\n return;\n }\n\n final Date now = new Date();\n final CommonTypes.Uuid userIdUuid = request.getUserId();\n final UUID userIdUUID = UUID.fromString(userIdUuid.getValue());\n final String firstName = request.getFirstName();\n final String lastName = request.getLastName();\n\n final String hashedPassword = HashUtils.hashPassword(request.getPassword().trim());\n final String email = request.getEmail();\n final String dupUserMessaage = String.format(\"Exception creating user because it already exists with email %s\", email);\n\n final BoundStatement checkEmailQuery = createUser_checkEmailPrepared.bind()\n .setString(\"email\", email)\n .setString(\"password\", hashedPassword)\n .setUUID(\"userid\", userIdUUID);\n\n ResultSet checkEmailResultSet = dseSession.execute(checkEmailQuery);\n if (!checkEmailResultSet.wasApplied()) {\n responseObserver.onError(Status.INVALID_ARGUMENT\n .augmentDescription(dupUserMessaage).asRuntimeException());\n responseObserver.onCompleted();\n return;\n }\n\n final BoundStatement insertUser = createUser_insertUserPrepared.bind()\n .setUUID(\"userid\", userIdUUID)\n .setString(\"firstname\", firstName)\n .setString(\"lastname\", lastName)\n .setString(\"email\", email)\n .setTimestamp(\"created_date\", now);\n\n ResultSet insertUserResultSet = dseSession.execute(insertUser);\n\n if(!insertUserResultSet.wasApplied()) {\n responseObserver.onError(Status.INVALID_ARGUMENT\n .augmentDescription(\"User ID not unique\").asRuntimeException());\n responseObserver.onCompleted();\n return;\n }\n\n responseObserver.onNext(CreateUserResponse.newBuilder().build());\n responseObserver.onCompleted();\n}\n\n```","12":"markdown","13":{"1":"585f7329-3382-4d12-a36d-df6ffdf360be","10":{"9":"<p>The entire <code>createUser()</code> function should look like so:</p>\n<pre><code>@Override\npublic void createUser(CreateUserRequest request, StreamObserver<CreateUserResponse> responseObserver) {\n if (!validator.isValid(request, responseObserver)) {\n return;\n }\n\n final Date now = new Date();\n final CommonTypes.Uuid userIdUuid = request.getUserId();\n final UUID userIdUUID = UUID.fromString(userIdUuid.getValue());\n final String firstName = request.getFirstName();\n final String lastName = request.getLastName();\n\n final String hashedPassword = HashUtils.hashPassword(request.getPassword().trim());\n final String email = request.getEmail();\n final String dupUserMessaage = String.format(\"Exception creating user because it already exists with email %s\", email);\n\n final BoundStatement checkEmailQuery = createUser_checkEmailPrepared.bind()\n .setString(\"email\", email)\n .setString(\"password\", hashedPassword)\n .setUUID(\"userid\", userIdUUID);\n\n ResultSet checkEmailResultSet = dseSession.execute(checkEmailQuery);\n if (!checkEmailResultSet.wasApplied()) {\n responseObserver.onError(Status.INVALID_ARGUMENT\n .augmentDescription(dupUserMessaage).asRuntimeException());\n responseObserver.onCompleted();\n return;\n }\n\n final BoundStatement insertUser = createUser_insertUserPrepared.bind()\n .setUUID(\"userid\", userIdUUID)\n .setString(\"firstname\", firstName)\n .setString(\"lastname\", lastName)\n .setString(\"email\", email)\n .setTimestamp(\"created_date\", now);\n\n ResultSet insertUserResultSet = dseSession.execute(insertUser);\n\n if(!insertUserResultSet.wasApplied()) {\n responseObserver.onError(Status.INVALID_ARGUMENT\n .augmentDescription(\"User ID not unique\").asRuntimeException());\n responseObserver.onCompleted();\n return;\n }\n\n responseObserver.onNext(CreateUserResponse.newBuilder().build());\n responseObserver.onCompleted();\n}\n</code></pre>\n"},"11":4,"12":false},"16":true,"17":true,"18":{},"25":"CL.ONE"},{"1":"822647fd-3697-43df-b733-4f5196bac664","10":4,"11":"Stop your previously running KillrVideo instance by clicking on the `X` under the `Machines` area towards the bottom of your Eclipse Che window.\n\n<center>![Close Application](https://s3.amazonaws.com/datastaxtraining/developer-day/app-dev/close-appplication.PNG \"Close Application\" )</center>\n\nClick OK to confirm this action.\n\nThen re-run your application but using the `ALT-R` hot key.\n\nThen go ahead and re-register then sign in with the user information you registered on the site with earlier. If it works properly, the site will redirect you to the home page.\n\nYAY!","12":"markdown","13":{"1":"3986b718-ba55-4c6d-bdad-b489c9ffd0b5","10":{"9":"<p>Stop your previously running KillrVideo instance by clicking on the <code>X</code> under the <code>Machines</code> area towards the bottom of your Eclipse Che window.</p>\n<p><center><img src=\"https://s3.amazonaws.com/datastaxtraining/developer-day/app-dev/close-appplication.PNG\" alt=\"Close Application\" title=\"Close Application\" /></center></p>\n<p>Click OK to confirm this action.</p>\n<p>Then re-run your application but using the <code>ALT-R</code> hot key.</p>\n<p>Then go ahead and re-register then sign in with the user information you registered on the site with earlier. If it works properly, the site will redirect you to the home page.</p>\n<p>YAY!</p>\n"},"11":4,"12":false},"16":true,"17":true,"18":{},"25":"CL.ONE"}],"16":{"1":{}},"17":"KillrVideoGraph"} code.txt 0100644 0000000 0000000 00000025023 13355211672 011267 0 ustar 00 0000000 0000000 --------------------NOTEBOOK_DSE Application Development: Prepared Statements--------------------
--------------------CELL_MARKDOWN_1--------------------
<center></center>
--------------------CELL_MARKDOWN_2--------------------
In this exercise, you will add the code to the KillrVideo application to insert a new user. First, open your web-based Eclipse editor by visiting the url: `http://<your-che-node-IP-address>:8080/dashboard/#/ide/che/killrvideo`.
--------------------CELL_MARKDOWN_3--------------------
Run the application by pressing the blue execute arrow at the top or by using the keyboard shortcut `ALT-R` (or `COMMAND-R` on Mac).
<center></center>
Once the application is running, navigate to `http://<your-web-node-ip-address>:3000`, and notice the webpage loads.
<center></center>
Go ahead and follow the steps to create a new user by clicking on the green `REGISTER` button to the upper right.
<center></center>
<center></center>
Notice the registration is broken, and the button just hangs indefinitely. WAH WAHHHH.
<center></center>
--------------------CELL_MARKDOWN_4--------------------
Your mission, should you choose to accept it, is to make the user sign-on process work. No stress. We will take you through it. First off, in your Eclipse Che `killrvideo` workspace, navigate to and open the file `/killrvideo-java/src/main/java/killrvideo/service/UserManagementService.java`.
<center></center>
Find the following comment:
```
// DECLARE THOSE FIELDS!
```
The first fields we will declare are two prepared statments:
1) Check that a user email doesn't already exist in the `user_credentials` table.
2) Insert the full user information into the `users` table.
Copy the following lines of code and paste them over the comment:
```
private PreparedStatement createUser_checkEmailPrepared;
private PreparedStatement createUser_insertUserPrepared;
```
Notice both are a `PreparedStatement` which means the cluster will compile the statement distribute the statement once, and we can fill in the variables later. `PreparedStatements` are faster this way over using `SimpleStatements` which must compile and distribute the query every time.
--------------------CELL_MARKDOWN_5--------------------
Now find the following comment in the same file:
```
// PREPARE THOSE STATEMENTS!
```
and replace it with the following code:
```
createUser_checkEmailPrepared = dseSession.prepare(
QueryBuilder
.insertInto(Schema.KEYSPACE, userCredentialsTableName)
.value("email", QueryBuilder.bindMarker())
.value("password", QueryBuilder.bindMarker())
.value("userid", QueryBuilder.bindMarker())
.ifNotExists() // use lightweight transaction
).setConsistencyLevel(ConsistencyLevel.LOCAL_QUORUM);
createUser_insertUserPrepared = dseSession.prepare(
QueryBuilder
.insertInto(Schema.KEYSPACE, usersTableName)
.value("userid", QueryBuilder.bindMarker())
.value("firstname", QueryBuilder.bindMarker())
.value("lastname", QueryBuilder.bindMarker())
.value("email", QueryBuilder.bindMarker())
.value("created_date", QueryBuilder.bindMarker())
.ifNotExists() // use lightweight transaction
).setConsistencyLevel(ConsistencyLevel.LOCAL_QUORUM);
```
Notice we use `QueryBuilder` to draft up our query, placing `bindMarker()`s where the insert variables will later go. We also set the consistency level on both queries and a lightweight transaction to avoid duplicate users. `dseSession.prepare()` is where the compile-once-and-reuse magic happens. All we need to do now is `bind()` our prepared statement variables to actual values and `execute()` the result.
--------------------CELL_MARKDOWN_6--------------------
Now find the following comment within that same file:
```
// CREATE THAT USER!
```
Here we will bind our variables and execute our insert.
Paste the following code over that comment:
```
if (!validator.isValid(request, responseObserver)) {
return;
}
```
This simply validates that the HTTP request is valid. Now add the following code below that:
```
final Date now = new Date();
final CommonTypes.Uuid userIdUuid = request.getUserId();
final UUID userIdUUID = UUID.fromString(userIdUuid.getValue());
final String firstName = request.getFirstName();
final String lastName = request.getLastName();
final String hashedPassword = HashUtils.hashPassword(request.getPassword().trim());
final String email = request.getEmail();
final String dupUserMessaage = String.format("Exception creating user because it already exists with email %s", email);
```
This pulls the values we are interested out of the HTTP request.
Now add the following:
```
final BoundStatement checkEmailQuery = createUser_checkEmailPrepared.bind()
.setString("email", email)
.setString("password", hashedPassword)
.setUUID("userid", userIdUUID);
```
This binds our `createUser_checkEmailPrepared` prepared statment to actual values, making a `BoundStatement` that we can actually `execute()`.
Continue adding:
```
ResultSet checkEmailResultSet = dseSession.execute(checkEmailQuery);
if (!checkEmailResultSet.wasApplied()) {
responseObserver.onError(Status.INVALID_ARGUMENT
.augmentDescription(dupUserMessaage).asRuntimeException());
responseObserver.onCompleted();
return;
}
```
Here we `execute()` our `BoundStatment` and further check that the insert `wasApplied()`. If not, we return an error.
Continue adding code:
```
final BoundStatement insertUser = createUser_insertUserPrepared.bind()
.setUUID("userid", userIdUUID)
.setString("firstname", firstName)
.setString("lastname", lastName)
.setString("email", email)
.setTimestamp("created_date", now);
ResultSet insertUserResultSet = dseSession.execute(insertUser);
if(!insertUserResultSet.wasApplied()) {
responseObserver.onError(Status.INVALID_ARGUMENT
.augmentDescription("User ID not unique").asRuntimeException());
responseObserver.onCompleted();
return;
}
```
This inserts the full user record into the `users` table. Again we check that the result applied.
Now finish serving the HTTP request by adding the following:
```
responseObserver.onNext(CreateUserResponse.newBuilder().build());
responseObserver.onCompleted();
```
--------------------CELL_MARKDOWN_7--------------------
The entire `createUser()` function should look like so:
```
@Override
public void createUser(CreateUserRequest request, StreamObserver<CreateUserResponse> responseObserver) {
if (!validator.isValid(request, responseObserver)) {
return;
}
final Date now = new Date();
final CommonTypes.Uuid userIdUuid = request.getUserId();
final UUID userIdUUID = UUID.fromString(userIdUuid.getValue());
final String firstName = request.getFirstName();
final String lastName = request.getLastName();
final String hashedPassword = HashUtils.hashPassword(request.getPassword().trim());
final String email = request.getEmail();
final String dupUserMessaage = String.format("Exception creating user because it already exists with email %s", email);
final BoundStatement checkEmailQuery = createUser_checkEmailPrepared.bind()
.setString("email", email)
.setString("password", hashedPassword)
.setUUID("userid", userIdUUID);
ResultSet checkEmailResultSet = dseSession.execute(checkEmailQuery);
if (!checkEmailResultSet.wasApplied()) {
responseObserver.onError(Status.INVALID_ARGUMENT
.augmentDescription(dupUserMessaage).asRuntimeException());
responseObserver.onCompleted();
return;
}
final BoundStatement insertUser = createUser_insertUserPrepared.bind()
.setUUID("userid", userIdUUID)
.setString("firstname", firstName)
.setString("lastname", lastName)
.setString("email", email)
.setTimestamp("created_date", now);
ResultSet insertUserResultSet = dseSession.execute(insertUser);
if(!insertUserResultSet.wasApplied()) {
responseObserver.onError(Status.INVALID_ARGUMENT
.augmentDescription("User ID not unique").asRuntimeException());
responseObserver.onCompleted();
return;
}
responseObserver.onNext(CreateUserResponse.newBuilder().build());
responseObserver.onCompleted();
}
```
--------------------CELL_MARKDOWN_8--------------------
Stop your previously running KillrVideo instance by clicking on the `X` under the `Machines` area towards the bottom of your Eclipse Che window.
<center></center>
Click OK to confirm this action.
Then re-run your application but using the `ALT-R` hot key.
Then go ahead and re-register then sign in with the user information you registered on the site with earlier. If it works properly, the site will redirect you to the home page.
YAY!
versions-info.txt 0100644 0000000 0000000 00000000026 13355211672 013152 0 ustar 00 0000000 0000000 Studio Version: 6.0.2