Changes for page Your First Rest Project

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

From version 39.1
edited by Pascal Robert
on 2012/12/12 08:01
Change comment: There is no comment for this version
To version 46.1
edited by Filippo Laurìa
on 2013/07/22 12:55
Change comment: There is no comment for this version

Summary

Details

Page properties
Author
... ... @@ -1,1 +1,1 @@
1 -XWiki.probert
1 +XWiki.filippolauria
Content
... ... @@ -1,5 +2,7 @@
1 -{{toc}}{{/toc}}
2 2  
2 +
3 +{{toc/}}
4 +
3 3  = Introduction =
4 4  
5 5  In the first part of the Blog tutorial, you will learn:
... ... @@ -20,21 +20,93 @@
20 20  
21 21  BlogEntry will have the following columns:
22 22  
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
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 +)))
30 30  
31 31  Author will have the following columns:
32 32  
33 -|= Column name |= Type |= Constraints
34 -| id | integer | primary key
35 -| firstName | string(50) |
36 -| lastName | string(50) |
37 -| email | string(100) | unique
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 +)))
38 38  
39 39  == Creating the EOModel ==
40 40  
... ... @@ -42,16 +42,24 @@
42 42  
43 43  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.
44 44  
45 -To create the EOModel, in the project right-click on the project name and select **New** > **EOModel**.
119 +To create the EOModel, in the project right-click on the project name and select **New** -> **EOModel**.
46 46  
47 47  Name it **BlogModel** and in the plugin list, select **H2**. Click **Finish**.
48 48  
49 49  The model should show up in a window that looks like this:
50 50  
125 +[[image:attach:EOModeler.png]]
126 +
51 51  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.
52 52  
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).
129 +In the Entity Modeler window, click on **Default**, and for the **URL** field, type
54 54  
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 +
55 55  Now, right-click on **BlogModel** and select **New Entity**.
56 56  
57 57  Type the following details in the **Basic** tab:
... ... @@ -72,36 +72,97 @@
72 72  
73 73  Now, repeat the last two steps to create the other attributes for the **BlogEntry** entity, with the following values:
74 74  
75 -|= Attribute name |= Column |= Prototype
76 -| content | content | longtext
77 -| creationDate | creationDate | dateTime
78 -| lastModified | lastModified | dateTime
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 +)))
79 79  
80 80  If you did everything well, the list of attributes should look like this:
81 81  
188 +[[image:attach:list_wlock.png]]
189 +
82 82  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:
83 83  
192 +[[image:attach:list.png]]
193 +
84 84  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:
85 85  
86 -|= Attribute name |= Column |= Prototype
87 -| firstName | firstName | varchar50
88 -| lastName | lastName | varchar50
89 -| email | email | varchar100
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 +)))
90 90  
91 91  Final list of attributes should look like this:
92 92  
227 +[[image:attach:author_list.png]]
228 +
93 93  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:
94 94  
231 +[[image:attach:relationship.png]]
232 +
95 95  If you check in the **Outline** tab, you should see that **Author** now have a **blogEntries** relationship, and **BlogEntry** have a **author** relationship.
96 96  
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**.
235 +[[image:attach:outline_tab.png]]
98 98  
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.
237 +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"]].)
100 100  
239 +
240 +
241 +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.
242 +
243 +
244 +
101 101  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:
102 102  
103 103  {{code}}
104 -
105 105  public String fullName() {
106 106   return this.firstName() + " " + this.lastName();
107 107   }
... ... @@ -111,16 +111,17 @@
111 111  Nothing fancy here. Now open **BlogEntry.java** and add the following method:
112 112  
113 113  {{code}}
114 -
115 -@Override
257 + @Override
116 116   public void awakeFromInsertion(EOEditingContext editingContext) {
117 - super.awakeFromInsertion(editingContext);
118 - this.setCreationDate(new NSTimestamp());
259 + super.awakeFromInsertion(editingContext);
260 + NSTimestamp now = new NSTimestamp();
261 + setCreationDate(now);
262 + setLastModified(now);
119 119   }
120 120  
121 121  {{/code}}
122 122  
123 -Why are we adding this? **awakeFromInsertion** is a very good way of setting default values when creating a new instance of a Enterprise Object (EO). In this case, we want to set automatically the creation date without having the user to add that value.
267 +Why are we adding this? **awakeFromInsertion** is a very good way of setting default values when creating a new instance of a Enterprise Object (EO). In this case, we want to set automatically the creation and last modification dates without having the user to add those values.
124 124  
125 125  Now, let's use migrations to actually create the database.
126 126  
... ... @@ -139,7 +139,6 @@
139 139  Remove the pound char in front of those two properties:
140 140  
141 141  {{code}}
142 -
143 143  #er.migration.migrateAtStartup=true
144 144  #er.migration.createTablesIfNecessary=true
145 145  
... ... @@ -148,16 +148,14 @@
148 148  After removing the pound char, the two properties should look like this:
149 149  
150 150  {{code}}
151 -
152 152  er.migration.migrateAtStartup=true
153 153  er.migration.createTablesIfNecessary=true
154 154  
155 155  {{/code}}
156 156  
157 -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:
299 +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:
158 158  
159 159  {{code}}
160 -
161 161  BlogRest[62990] INFO er.extensions.migration.ERXMigrator - Upgrading BlogModel to version 0 with migration 'your.app.model.migrations.BlogModel0@4743bf3d'
162 162  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)
163 163  BlogRest[62990] INFO er.extensions.jdbc.ERXJDBCUtilities - Executing ALTER TABLE Author ADD PRIMARY KEY (id)
... ... @@ -168,7 +168,7 @@
168 168  
169 169  {{/code}}
170 170  
171 -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.
312 +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.
172 172  
173 173  = Creating REST controllers and routes =
174 174  
... ... @@ -205,15 +205,14 @@
205 205  * **indexAction**: to list all (or a sublist) of the objects.
206 206  
207 207  {{info}}
208 -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.
349 +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.
209 209  {{/info}}
210 210  
211 -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)
352 +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)!
212 212  
213 213  Add this method in **BlogEntryController**:
214 214  
215 215  {{code}}
216 -
217 217  protected ERXKeyFilter filter() {
218 218   ERXKeyFilter personFilter = ERXKeyFilter.filterWithAttributes();
219 219   personFilter.setAnonymousUpdateEnabled(true);
... ... @@ -230,7 +230,6 @@
230 230  Now, let's implement the **createAction** method:
231 231  
232 232  {{code}}
233 -
234 234  public WOActionResults createAction() throws Throwable {
235 235   BlogEntry entry = create(filter());
236 236   editingContext().saveChanges();
... ... @@ -244,7 +244,6 @@
244 244  Last step in the controller: implementing the **indexAction** method. Again, the code is simple:
245 245  
246 246  {{code}}
247 -
248 248  public WOActionResults indexAction() throws Throwable {
249 249   NSArray<BlogEntry> entries = BlogEntry.fetchAllBlogEntries(editingContext());
250 250   return response(entries, filter());
... ... @@ -261,7 +261,6 @@
261 261  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:
262 262  
263 263  {{code}}
264 -
265 265  ERXRouteRequestHandler restRequestHandler = new ERXRouteRequestHandler();
266 266   restRequestHandler.addDefaultRoutes(BlogEntry.ENTITY_NAME);
267 267   ERXRouteRequestHandler.register(restRequestHandler);
... ... @@ -271,13 +271,13 @@
271 271  
272 272  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.
273 273  
274 -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_]]//
411 +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"]]
275 275  
276 276  == Adding posts and authors with curl ==
277 277  
278 278  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.
279 279  
280 -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:
417 +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:
281 281  
282 282  {{code}}
283 283  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
... ... @@ -286,7 +286,6 @@
286 286  The response should look this:
287 287  
288 288  {{code}}
289 -
290 290  HTTP/1.0 201 Apple WebObjects
291 291  Content-Length: 249
292 292  x-webobjects-loadaverage: 0
... ... @@ -299,7 +299,6 @@
299 299  To get a list of blog entries:
300 300  
301 301  {{code}}
302 -
303 303  curl -X GET http://192.168.0.102:52406/cgi-bin/WebObjects/BlogRest.woa/ra/blogEntries.json
304 304  
305 305  {{/code}}
... ... @@ -311,7 +311,6 @@
311 311  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:
312 312  
313 313  {{code}}
314 -
315 315  @Override
316 316   protected boolean isAutomaticHtmlRoutingEnabled() {
317 317   return true;
... ... @@ -319,12 +319,11 @@
319 319  
320 320  {{/code}}
321 321  
322 -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**.
456 +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**.
323 323  
324 324  The next step to get it to work is to make **BlogEntryIndexPage** to implement the **er.rest.routes.IERXRouteComponent** interface.
325 325  
326 326  {{code}}
327 -
328 328  import er.rest.routes.IERXRouteComponent;
329 329  
330 330  public class BlogEntryIndexPage extends WOComponent implements IERXRouteComponent {
... ... @@ -334,7 +334,6 @@
334 334  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:
335 335  
336 336  {{code}}
337 -
338 338  public NSArray<BlogEntry> entries() {
339 339   EOEditingContext ec = ERXEC.newEditingContext();
340 340   return BlogEntry.fetchAllBlogEntries(ec, BlogEntry.CREATION_DATE.descs());
... ... @@ -345,7 +345,6 @@
345 345  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**:
346 346  
347 347  {{code}}
348 -
349 349  private BlogEntry entryItem;
350 350  
351 351   public BlogEntry entryItem() {
... ... @@ -361,7 +361,6 @@
361 361  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:
362 362  
363 363  {{code}}
364 -
365 365  <wo:loop list="$entries" item="$entryItem">
366 366   <p><wo:str value="$entryItem.title" /></p>
367 367   <p><wo:str value="$entryItem.author.fullName" /></p>
... ... @@ -371,14 +371,13 @@
371 371  
372 372  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.
373 373  
374 -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
504 +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!
375 375  
376 376  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**.
377 377  
378 -Open **BlogEntryShowPage.java** and make sure the class implements&nbsp;**er.rest.routes.IERXRouteComponent**.
508 +Open **BlogEntryShowPage.java** and make sure the class implements **er.rest.routes.IERXRouteComponent**.
379 379  
380 380  {{code}}
381 -
382 382  import er.rest.routes.IERXRouteComponent;
383 383  
384 384  public class BlogEntryShowPage extends WOComponent implements IERXRouteComponent {
... ... @@ -388,7 +388,6 @@
388 388  We need to add other methods to receive the BlogEntry object from the controller. In **BlogEntryShowPage.java**, add:
389 389  
390 390  {{code}}
391 -
392 392  private BlogEntry blogEntry;
393 393  
394 394   @ERXRouteParameter
... ... @@ -407,7 +407,6 @@
407 407  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:
408 408  
409 409  {{code}}
410 -
411 411  <h1><wo:str value="$blogEntry.title" /></h1>
412 412   <p><wo:str value="$blogEntry.content" /></p>
413 413   <p>Created on: <wo:str value="$blogEntry.creationDate" dateformat="%Y/%m/%d" /></p>
... ... @@ -418,7 +418,6 @@
418 418  Our view component is done, the only thing remaining is a link for the blog entry list (BlogEntryIndexPage) to the view page (BlogEntryShowPage). Save **BlogEntryShowPage.wo** and open **BlogEntryIndexPage.wo**. We are going to add a link on the title, you will replace to replace this:
419 419  
420 420  {{code}}
421 -
422 422  <p><wo:str value="$entryItem.title" /></p>
423 423  
424 424  {{/code}}
... ... @@ -426,11 +426,10 @@
426 426  with:
427 427  
428 428  {{code}}
429 -
430 430  <p><wo:ERXRouteLink entityName="BlogEntry" record="$entryItem" action="show"><wo:str value="$entryItem.title" /></wo:ERXRouteLink></p>
431 431  
432 432  {{/code}}
433 433  
434 -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
559 +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!
435 435  
436 -The REST part of this tutorial is now complete, [[you can now move to the next part of the tutorial>>Your First Framework]].
561 +The REST part of this tutorial is now complete, [[you can now move to the next part of the tutorial>>doc:Your First Framework]].