Changes for page Your First Rest Project

Last modified by Steve Peery on 2013/09/06 11:02

From version 27.1
edited by Filippo Laurìa
on 2013/07/22 12:51
Change comment: There is no comment for this version
To version 25.1
edited by steffan
on 2013/02/10 18:44
Change comment: Fix validation error when POSTing a blog entry by setting lastModified value

Summary

Details

Page properties
Author
... ... @@ -1,1 +1,1 @@
1 -XWiki.filippolauria
1 +XWiki.steffan
Content
... ... @@ -1,7 +1,5 @@
1 +{{toc}}{{/toc}}
1 1  
2 -
3 -{{toc/}}
4 -
5 5  = Introduction =
6 6  
7 7  In the first part of the Blog tutorial, you will learn:
... ... @@ -22,93 +22,21 @@
22 22  
23 23  BlogEntry will have the following columns:
24 24  
25 -|=(((
26 -Column name
27 -)))|=(((
28 -Type
29 -)))|=(((
30 -Constraints
31 -)))
32 -|(((
33 -id
34 -)))|(((
35 -integer
36 -)))|(((
37 -primary key
38 -)))
39 -|(((
40 -title
41 -)))|(((
42 -string(255)
43 -)))|(((
44 -
45 -)))
46 -|(((
47 -content
48 -)))|(((
49 -string(4000)
50 -)))|(((
51 -
52 -)))
53 -|(((
54 -creationDate
55 -)))|(((
56 -timestamp
57 -)))|(((
58 -
59 -)))
60 -|(((
61 -lastModified
62 -)))|(((
63 -timestamp
64 -)))|(((
65 -
66 -)))
67 -|(((
68 -author
69 -)))|(((
70 -integer
71 -)))|(((
72 -relation with Author
73 -)))
23 +|= Column name |= Type |= Constraints
24 +| id | integer | primary key
25 +| title | string(255) |
26 +| content | string(4000) |
27 +| creationDate | timestamp |
28 +| lastModified | timestamp |
29 +| author | integer | relation with Author
74 74  
75 75  Author will have the following columns:
76 76  
77 -|=(((
78 -Column name
79 -)))|=(((
80 -Type
81 -)))|=(((
82 -Constraints
83 -)))
84 -|(((
85 -id
86 -)))|(((
87 -integer
88 -)))|(((
89 -primary key
90 -)))
91 -|(((
92 -firstName
93 -)))|(((
94 -string(50)
95 -)))|(((
96 -
97 -)))
98 -|(((
99 -lastName
100 -)))|(((
101 -string(50)
102 -)))|(((
103 -
104 -)))
105 -|(((
106 -email
107 -)))|(((
108 -string(100)
109 -)))|(((
110 -unique
111 -)))
33 +|= Column name |= Type |= Constraints
34 +| id | integer | primary key
35 +| firstName | string(50) |
36 +| lastName | string(50) |
37 +| email | string(100) | unique
112 112  
113 113  == Creating the EOModel ==
114 114  
... ... @@ -116,24 +116,16 @@
116 116  
117 117  An EOModel consists of entities, attributes and relationships. When using it in a RDBMS context, an entity is a table (or a view), an attribute is a table column and a relationship is a join between two tables.
118 118  
119 -To create the EOModel, in the project right-click on the project name and select **New** -> **EOModel**.
45 +To create the EOModel, in the project right-click on the project name and select **New** > **EOModel**.
120 120  
121 121  Name it **BlogModel** and in the plugin list, select **H2**. Click **Finish**.
122 122  
123 123  The model should show up in a window that looks like this:
124 124  
125 -[[image:attach:EOModeler.png]]
126 -
127 127  If it didn't show up, the window might have opened behind the main Eclipse window. If that's the case, open the **Window** menu and select the windows that have //Entity Modeler// in its name.
128 128  
129 -In the Entity Modeler window, click on **Default**, and for the **URL** field, type
53 +In the Entity Modeler window, click on **Default**, and for the **URL** field, type {{code}}jdbc:h2:~/BlogTutorial{{/code}}. When the database will be created, it will be stored in your home directory (/Users/youruser/ on OS X).
130 130  
131 -{{code}}
132 -jdbc:h2:~/BlogTutorial
133 -{{/code}}
134 -
135 -. When the database will be created, it will be stored in your home directory (/Users/youruser/ on OS X).
136 -
137 137  Now, right-click on **BlogModel** and select **New Entity**.
138 138  
139 139  Type the following details in the **Basic** tab:
... ... @@ -154,91 +154,36 @@
154 154  
155 155  Now, repeat the last two steps to create the other attributes for the **BlogEntry** entity, with the following values:
156 156  
157 -|=(((
158 -Attribute name
159 -)))|=(((
160 -Column
161 -)))|=(((
162 -Prototype
163 -)))
164 -|(((
165 -content
166 -)))|(((
167 -content
168 -)))|(((
169 -longtext
170 -)))
171 -|(((
172 -creationDate
173 -)))|(((
174 -creationDate
175 -)))|(((
176 -dateTime
177 -)))
178 -|(((
179 -lastModified
180 -)))|(((
181 -lastModified
182 -)))|(((
183 -dateTime
184 -)))
75 +|= Attribute name |= Column |= Prototype
76 +| content | content | longtext
77 +| creationDate | creationDate | dateTime
78 +| lastModified | lastModified | dateTime
185 185  
186 186  If you did everything well, the list of attributes should look like this:
187 187  
188 -[[image:attach:list_wlock.png]]
189 -
190 190  You will notice that the attributes have a column with a lock in it. When a lock is present, it will use the value of that attribute for //UPDATE ... WHERE attribute = ''// statement. This is to do optimistic locking, aka to prevent data conflict when the data object was modified by two different users. Using timestamps for optimistic locking is not a good idea because for certain RDBMS, the value can be different because of milliseconds, so remove the locks on the **creationDate** attribute. The final list should look like this:
191 191  
192 -[[image:attach:list.png]]
193 -
194 194  Next step is to create the **Author** entity. Create a new entity with **Author** at its name (and also as the table name), and for the class name, use **your.app.model.Author**. The attributes for this entity are:
195 195  
196 -|=(((
197 -Attribute name
198 -)))|=(((
199 -Column
200 -)))|=(((
201 -Prototype
202 -)))
203 -|(((
204 -firstName
205 -)))|(((
206 -firstName
207 -)))|(((
208 -varchar50
209 -)))
210 -|(((
211 -lastName
212 -)))|(((
213 -lastName
214 -)))|(((
215 -varchar50
216 -)))
217 -|(((
218 -email
219 -)))|(((
220 -email
221 -)))|(((
222 -varchar100
223 -)))
86 +|= Attribute name |= Column |= Prototype
87 +| firstName | firstName | varchar50
88 +| lastName | lastName | varchar50
89 +| email | email | varchar100
224 224  
225 225  Final list of attributes should look like this:
226 226  
227 -[[image:attach:author_list.png]]
228 -
229 229  Now, it's time to link the two entities together. An Author can have multiple blog entries, and a BlogEntry can only have one author. To create the relationship (the join), right-click on **Author** and select **New Relationship**. On your right, select **BlogEntry** in the list. On your left, select **to many BlogEntries**, and on your right, select **to one Author**. Now, in BlogEntry, we need to store the primary key of the author so that we can make the join. The relationship builder allow us to add that attribute, so make sure **and a new foreign key named** is checked (it is checked by default). The **Create Relationship** pane should look like this:
230 230  
231 -[[image:attach:relationship.png]]
232 -
233 233  If you check in the **Outline** tab, you should see that **Author** now have a **blogEntries** relationship, and **BlogEntry** have a **author** relationship.
234 234  
235 -You are now ready to save the model. Save it (File -> Save) and close the **Entity Modeler** window. If you open the **Sources** in the main Eclipse window, you will notice that the **Sources** folder contains a package named **your.app.model**. (If this folder doesn't appear, you may need to set your preferences to automatically generate these source files; see the second suggestion on [[http:~~/~~/wiki.wocommunity.org/display/documentation/Useful+Eclipse+or+WOLips+Preferences>>url:http://wiki.wocommunity.org/display/documentation/Useful+Eclipse+or+WOLips+Preferences||rel="nofollow" shape="rect" class="external-link"]].)
97 +You are now ready to save the model. Save it (File > Save) and close the **Entity Modeler** window. If you open the **Sources** in the main Eclipse window, you will notice that the **Sources** folder contains a package named **your.app.model**.
236 236  
237 -That package have four Java classes: **_Author**, **Author**, **_BlogEntry** and **BlogEntry**. Those classes were generated by Veogen, a templating engine build on Velocity. The two classes that starts with a underscore are recreated every time you change the EOModel, so if you want to change something in those classes, you need to change the template (no need for that right now). But you can change freely the two classes that don't have the underscore, and this is what we will be doing.
99 +That package have four Java classes: **Author**, **Author**, **BlogEntry** and **BlogEntry**. Those classes were generated by Veogen, a templating engine build on Velocity. The two classes that starts with a underscore are recreated every time you change the EOModel, so if you want to change something in those classes, you need to change the template (no need for that right now). But you can change freely the two classes that don't have the underscore, and this is what we will be doing.
238 238  
239 239  What we are going to do is to write a simple method that returns the full name of an author, e.g. a method that simply concatenate the first name, a space and the last name of the author. To do so, double-click on **Author.java** and add the following methods:
240 240  
241 241  {{code}}
104 +
242 242  public String fullName() {
243 243   return this.firstName() + " " + this.lastName();
244 244   }
... ... @@ -248,6 +248,7 @@
248 248  Nothing fancy here. Now open **BlogEntry.java** and add the following method:
249 249  
250 250  {{code}}
114 +
251 251   @Override
252 252   public void awakeFromInsertion(EOEditingContext editingContext) {
253 253   super.awakeFromInsertion(editingContext);
... ... @@ -277,6 +277,7 @@
277 277  Remove the pound char in front of those two properties:
278 278  
279 279  {{code}}
144 +
280 280  #er.migration.migrateAtStartup=true
281 281  #er.migration.createTablesIfNecessary=true
282 282  
... ... @@ -285,14 +285,16 @@
285 285  After removing the pound char, the two properties should look like this:
286 286  
287 287  {{code}}
153 +
288 288  er.migration.migrateAtStartup=true
289 289  er.migration.createTablesIfNecessary=true
290 290  
291 291  {{/code}}
292 292  
293 -You are now ready to start the application so that it creates the database! To do so, right-click on **Application.java** (in the **your.app** folder) and select **Run As** -> **WOApplication**. In Eclipse's Console tab, you should see some output, including something similar to:
159 +You are now ready to start the application so that it creates the database To do so, right-click on **Application.java** (in the **your.app** folder) and select **Run As** > **WOApplication**. In Eclipse's Console tab, you should see some output, including something similar to:
294 294  
295 295  {{code}}
162 +
296 296  BlogRest[62990] INFO er.extensions.migration.ERXMigrator - Upgrading BlogModel to version 0 with migration 'your.app.model.migrations.BlogModel0@4743bf3d'
297 297  BlogRest[62990] INFO er.extensions.jdbc.ERXJDBCUtilities - Executing CREATE TABLE Author(email VARCHAR(100) NOT NULL, firstName VARCHAR(50) NOT NULL, id INTEGER NOT NULL, lastName VARCHAR(50) NOT NULL)
298 298  BlogRest[62990] INFO er.extensions.jdbc.ERXJDBCUtilities - Executing ALTER TABLE Author ADD PRIMARY KEY (id)
... ... @@ -303,7 +303,7 @@
303 303  
304 304  {{/code}}
305 305  
306 -If you see this and that the application is running (it should open a window in your favorite browser), migration worked and your database have been created, congratulations! You can now stop the application (click the square red button in Eclipse's Console tab) and continue to the next step.
173 +If you see this and that the application is running (it should open a window in your favorite browser), migration worked and your database have been created, congratulations You can now stop the application (click the square red button in Eclipse's Console tab) and continue to the next step.
307 307  
308 308  = Creating REST controllers and routes =
309 309  
... ... @@ -340,14 +340,15 @@
340 340  * **indexAction**: to list all (or a sublist) of the objects.
341 341  
342 342  {{info}}
343 -In Project Wonder, **Action** at the end of a method is a convention for REST and Direct Actions, when you call those methods from certain components, you don't need to add the **Action** part.
210 +In Project Wonder, *Action* at the end of a method is a convention for REST and Direct Actions, when you call those methods from certain components, you don't need to add the *Action* part.
344 344  {{/info}}
345 345  
346 -For this tutorial, we will implement the **createAction** and **indexAction** methods. But first, we need to create a key filter. A key filter will... filter the input and the output of REST request so that you don't have to send all attributes for a blog entry. For example, we want to show the details for an author, but we don't want to show the password for the author (in real-life, the password would be encrypted)!
213 +For this tutorial, we will implement the **createAction** and **indexAction** methods. But first, we need to create a key filter. A key filter will... filter the input and the output of REST request so that you don't have to send all attributes for a blog entry. For example, we want to show the details for an author, but we don't want to show the password for the author (in real-life, the password would be encrypted)
347 347  
348 348  Add this method in **BlogEntryController**:
349 349  
350 350  {{code}}
218 +
351 351  protected ERXKeyFilter filter() {
352 352   ERXKeyFilter personFilter = ERXKeyFilter.filterWithAttributes();
353 353   personFilter.setAnonymousUpdateEnabled(true);
... ... @@ -364,6 +364,7 @@
364 364  Now, let's implement the **createAction** method:
365 365  
366 366  {{code}}
235 +
367 367  public WOActionResults createAction() throws Throwable {
368 368   BlogEntry entry = create(filter());
369 369   editingContext().saveChanges();
... ... @@ -377,6 +377,7 @@
377 377  Last step in the controller: implementing the **indexAction** method. Again, the code is simple:
378 378  
379 379  {{code}}
249 +
380 380  public WOActionResults indexAction() throws Throwable {
381 381   NSArray<BlogEntry> entries = BlogEntry.fetchAllBlogEntries(editingContext());
382 382   return response(entries, filter());
... ... @@ -393,6 +393,7 @@
393 393  A route in ERRest is simply a way to define the URL for the entities and to specify which controller the route should use. When your controller extends from **ERXDefaultRouteController**, it's easy to register a controller and a route. In **Application.java**, in the **Application** constructor, add the following code:
394 394  
395 395  {{code}}
266 +
396 396  ERXRouteRequestHandler restRequestHandler = new ERXRouteRequestHandler();
397 397   restRequestHandler.addDefaultRoutes(BlogEntry.ENTITY_NAME);
398 398   ERXRouteRequestHandler.register(restRequestHandler);
... ... @@ -402,13 +402,13 @@
402 402  
403 403  The **addDefaultRoutes** method do all of the required magic, and use convention. That's why we had to name the controller **BlogEntryController**, because the convention is <EntityName>Controller.
404 404  
405 -We are now reading to add and list blog postings! Start the application and take notice of the URL. It should be something like _[[http:~~/~~/yourip:someport/cgi-bin/WebObjects/BlogRest.woa_>>url:http://youripsomeport||shape="rect"]]
276 +We are now reading to add and list blog postings Start the application and take notice of the URL. It should be something like //[[http:~~/~~/yourip:someport/cgi-bin/WebObjects/BlogRest.woa>>http://yourip:someport/cgi-bin/WebObjects/BlogRest.woa_]]//
406 406  
407 407  == Adding posts and authors with curl ==
408 408  
409 409  Since we didn't implement any HTML for our REST routes, we will create blog entries with //curl//, an open source HTTP client that is bundled with Mac OS X (you can use another client, like wget, if you like too). So let's create a blog entry.
410 410  
411 -To create a blog entry, you need to use the POST HTTP method. We will use JSON as the format since it's a bit less chatty than XML. So if the URL to the application is //[[http:~~/~~/192.168.0.102:52406/cgi-bin/WebObjects/BlogRest.woa_>>url:http://192.168.0.102:52406/cgi-bin/WebObjects/BlogRest.woa_||shape="rect"]], the full _curl// command will be:
282 +To create a blog entry, you need to use the POST HTTP method. We will use JSON as the format since it's a bit less chatty than XML. So if the URL to the application is //[[http:~~/~~/192.168.0.102:52406/cgi-bin/WebObjects/BlogRest.woa>>http://192.168.0.102:52406/cgi-bin/WebObjects/BlogRest.woa_]], the full curl// command will be:
412 412  
413 413  {{code}}
414 414  curl -X POST -v -d '{ "title": "First post", "content": "Some text", "author": { "firstName": "Pascal", "lastName": "Robert", "email": "probert@macti.ca" } }' http://192.168.0.102:52406/cgi-bin/WebObjects/BlogRest.woa/ra/blogEntries.json
... ... @@ -417,6 +417,7 @@
417 417  The response should look this:
418 418  
419 419  {{code}}
291 +
420 420  HTTP/1.0 201 Apple WebObjects
421 421  Content-Length: 249
422 422  x-webobjects-loadaverage: 0
... ... @@ -429,6 +429,7 @@
429 429  To get a list of blog entries:
430 430  
431 431  {{code}}
304 +
432 432  curl -X GET http://192.168.0.102:52406/cgi-bin/WebObjects/BlogRest.woa/ra/blogEntries.json
433 433  
434 434  {{/code}}
... ... @@ -440,6 +440,7 @@
440 440  Now, let's build a HTML view for blog posts (you don't want your readers to get your posts by JSON, right?). Again, we will use convention to make it work easily. Open up **BlogEntryController** and add the following method:
441 441  
442 442  {{code}}
316 +
443 443  @Override
444 444   protected boolean isAutomaticHtmlRoutingEnabled() {
445 445   return true;
... ... @@ -447,11 +447,12 @@
447 447  
448 448  {{/code}}
449 449  
450 -Switching the return value of this method says that we will follow a certain convention for HTML components. The convention for automatic HTML routing is that the component should be named <EntityName><Action>Page.wo. So in our case, the component will be **BlogEntryIndexPage**. Right-click on the project name in Eclipse and select **New** -> **WOComponent**. Change the name to **BlogEntryIndexPage** and check the **Create HTML contents** button. Click **Finish**.
324 +Switching the return value of this method says that we will follow a certain convention for HTML components. The convention for automatic HTML routing is that the component should be named <EntityName><Action>Page.wo. So in our case, the component will be **BlogEntryIndexPage**. Right-click on the project name in Eclipse and select **New** > **WOComponent**. Change the name to **BlogEntryIndexPage** and check the **Create HTML contents** button. Click **Finish**.
451 451  
452 452  The next step to get it to work is to make **BlogEntryIndexPage** to implement the **er.rest.routes.IERXRouteComponent** interface.
453 453  
454 454  {{code}}
329 +
455 455  import er.rest.routes.IERXRouteComponent;
456 456  
457 457  public class BlogEntryIndexPage extends WOComponent implements IERXRouteComponent {
... ... @@ -461,6 +461,7 @@
461 461  So now, the automatic HTML routing will send the request for **ra/blogEntries.html** to the **BlogEntryIndexPage** component. But we don't have any content in this component, so let's make a method to fetch all blog entries per creation date in descending order. So in **BlogEntryIndexPage.java**, add the following method:
462 462  
463 463  {{code}}
339 +
464 464  public NSArray<BlogEntry> entries() {
465 465   EOEditingContext ec = ERXEC.newEditingContext();
466 466   return BlogEntry.fetchAllBlogEntries(ec, BlogEntry.CREATION_DATE.descs());
... ... @@ -471,6 +471,7 @@
471 471  We need to use that method in a WORepetition, and for that loop, we need a BlogEntry variable to iterate in the list, so add the following code to **BlogEntryIndexPage.java**:
472 472  
473 473  {{code}}
350 +
474 474  private BlogEntry entryItem;
475 475  
476 476   public BlogEntry entryItem() {
... ... @@ -486,6 +486,7 @@
486 486  The Java part is done, so let's add the loop inside the component. Open **BlogEntryIndexPage.wo** (it's located in the **Component** folder) and right after the <body> tag, add:
487 487  
488 488  {{code}}
366 +
489 489  <wo:loop list="$entries" item="$entryItem">
490 490   <p><wo:str value="$entryItem.title" /></p>
491 491   <p><wo:str value="$entryItem.author.fullName" /></p>
... ... @@ -495,13 +495,14 @@
495 495  
496 496  That component code will loop over the blog entries and display the title of the entry + the name of the author. Save everything and run the application.
497 497  
498 -If you go to [[http:~~/~~/192.168.0.102:52406/cgi-bin/WebObjects/BlogRest.woa/ra/blogEntries.html>>url:http://192.168.0.102:52406/cgi-bin/WebObjects/BlogRest.woa/ra/blogEntries.html||shape="rect"]], you will see the list of blog entries!
376 +If you go to [[http://192.168.0.102:52406/cgi-bin/WebObjects/BlogRest.woa/ra/blogEntries.html]], you will see the list of blog entries
499 499  
500 500  Now that we have a list of blog entries, let's make a page to show the content of a blog entry. Create a new component named **BlogEntryShowPage**.
501 501  
502 -Open **BlogEntryShowPage.java** and make sure the class implements **er.rest.routes.IERXRouteComponent**.
380 +Open **BlogEntryShowPage.java** and make sure the class implements&nbsp;**er.rest.routes.IERXRouteComponent**.
503 503  
504 504  {{code}}
383 +
505 505  import er.rest.routes.IERXRouteComponent;
506 506  
507 507  public class BlogEntryShowPage extends WOComponent implements IERXRouteComponent {
... ... @@ -511,6 +511,7 @@
511 511  We need to add other methods to receive the BlogEntry object from the controller. In **BlogEntryShowPage.java**, add:
512 512  
513 513  {{code}}
393 +
514 514  private BlogEntry blogEntry;
515 515  
516 516   @ERXRouteParameter
... ... @@ -529,6 +529,7 @@
529 529  The Java part of the work is done, so save the Java class. It's time to work on the component part. Open **BlogEntryShowPage.wo** and between the <body></body> part, add:
530 530  
531 531  {{code}}
412 +
532 532  <h1><wo:str value="$blogEntry.title" /></h1>
533 533   <p><wo:str value="$blogEntry.content" /></p>
534 534   <p>Created on: <wo:str value="$blogEntry.creationDate" dateformat="%Y/%m/%d" /></p>
... ... @@ -539,6 +539,7 @@
539 539  Our view component is done, the only thing remaining is a link for the blog entry list (BlogEntryIndexPage) to the view page (BlogEntryShowPage). Save **BlogEntryShowPage.wo** and open **BlogEntryIndexPage.wo**. We are going to add a link on the title, you will replace to replace this:
540 540  
541 541  {{code}}
423 +
542 542  <p><wo:str value="$entryItem.title" /></p>
543 543  
544 544  {{/code}}
... ... @@ -546,10 +546,11 @@
546 546  with:
547 547  
548 548  {{code}}
431 +
549 549  <p><wo:ERXRouteLink entityName="BlogEntry" record="$entryItem" action="show"><wo:str value="$entryItem.title" /></wo:ERXRouteLink></p>
550 550  
551 551  {{/code}}
552 552  
553 -Save the component and run the app. Go to [[http:~~/~~/192.168.0.102:52406/cgi-bin/WebObjects/BlogRest.woa/ra/blogEntries.html>>url:http://192.168.0.102:52406/cgi-bin/WebObjects/BlogRest.woa/ra/blogEntries.html||shape="rect"]] to get the list of posts, and you should see a link on the title. Click on it, and now you get the full details of the blog entry!
436 +Save the component and run the app. Go to [[http://192.168.0.102:52406/cgi-bin/WebObjects/BlogRest.woa/ra/blogEntries.html]] to get the list of posts, and you should see a link on the title. Click on it, and now you get the full details of the blog entry
554 554  
555 -The REST part of this tutorial is now complete, [[you can now move to the next part of the tutorial>>doc:Your First Framework]].
438 +The REST part of this tutorial is now complete, [[you can now move to the next part of the tutorial>>Your First Framework]].