Learning Drupal 6 Module Development

Errata type: Technical | Page number: 0

Note on code indentation:
The author says ""I have attempted to make the code in the book adhere to the Drupal coding standards (http://drupal.org/coding-standards). I suggest that, in Chapter 1, developers use the Coder module to help keep code close to that standard. However, there is no prolonged discussion in the book of what the standards are. For that information, readers should visit http://drupal.org/coding-standards."

Errata type: code | Page number: 0

In the download code, modul philquotes code_example.zip: function _philquotes_get_quote() /query statement: ...type='quotes'...(plural) In the book the statement is: ...type='quote'... (singular). Correction: 'quote' is correct.

Errata type: Technical | Page number: 18

The book says JSON stands for JavaScript Over The Network. But it actually stands for JavaScript Object Notation.

Errata type: Typo | Page number: 19

Under "Developers' Tools" there is a line that reads "These tools are themselves provided by two modules, which can both can be obtained from the Drupal site." This sentence should not contain the second "can".

Errata type: Technical | Page number: 20

In the list of development environments, vi and Firebug are incorrectly capitalised as "VI" and "FireBug".

Errata type: Typo | Page number: 38

The first line of the first paragraph should be "This tool" instead of "This tools"

Errata type: Typo | Page number: 40

The first line of the comments for the _gooreads_fetch_bookshelf($url, > $num_items = 3) functions has bookshelf spelt wrong as bookshelp.

Errata type: Technical | Page number: 40

In the second paragraph, the given RSS URL is not working anymore. The new RSS URL is http://www.goodreads.com/review/list_rss/398385

Errata type: code | Page number: 45

The part of the code under the topic 'Processing the HTTP Results' should read:
if($doc === false) {
$msg = "Error parsing bookshelf XML for %url.";
$vars = array('%url => $url); watchdog('goodreads', $msg, $vars, WATCHDOG_WARNING);
return t("Getting the bookshelf resulted in an error"); }

Errata type: Code | Page number: 46

The $num_items variable is not used to limit the number of items displayed (as it should be). The code sample on page 46 (repeated on page 49) should have included this around line 6 of the function:
if ($count_items > $num_items) {
$items = array_slice($items, 0, $num_items, TRUE); }
Since the variable $len is not used, it can be removed.
Alternately, the foreach loop could be replaced with a for loop, which was the
original design. In this case, $len is used:
// foreach ($items as $item) { // Not used anymore for ($i = 0; $i < $len; ++$i) {
$item = $items[$i];
// ... rest of the code goes here
}

Errata type: code | Page number: 57

In the code sample at the top of the page, default values for the $author and $title variables are left empty. They should have been set to 'Unknown' and 'Untitled', respectively. The correct code appears on page 49 and again on page 51 (where it is explained).

Errata type: Code | Page number: 47

There is a wrong line of code. It says "if (empty($link)) !== 0) $link = $default_link;" it should be "if (empty($link)) $link = $default_link;"

Errata type: Code | Page number: 49

The $num_items variable is not used to limit the number of items displayed (as it
should be). The code sample on page 46 (repeated on page 49) should have included
this around line 6 of the function:
if ($count_items > $num_items) {
$items = array_slice($items, 0, $num_items, TRUE); }
Since the variable $len is not used, it can be removed.
Alternately, the foreach loop could be replaced with a for loop, which was the
original design. In this case, $len is used:
// foreach ($items as $item) { // Not used anymore for ($i = 0; $i < $len; ++$i) {
$item = $items[$i];
// ... rest of the code goes here
}

Errata type: Typo | Page number: 52

In the first line of the fourth paragraph, it should be "That string is then added to $out." instead of "That string is then added to $output."

Errata type: Typo | Page number: 61

In the middle of the page 'labotomy' is misspelled in code block, it should be spelled 'lobotomy'

Errata type: Typo | Page number: 63

The first sentence on page 63 which reads, "In this book, we will use only of the PHPTemplate engine for the following reasons:", is grammatically wrong. The sentence should not contain "of".

Errata type: Typo | Page number: 68

The fourth paragraph has the sentence, "In our case, we are extending a theme that we did not create. Clearly, we would do best to put our MODULE in the drupal/sites/all areas." The word module should be theme.

Errata type: Code | Page number: 71

Right after the sixth line of code at the top of the page "background-color: white;" should be a line that is missing "float: right;".

Errata type: Code | Page number: 72

The current code says:
stylesheets[all][] = style.css
stylesheets[all][] = new.css
Should be like this:
stylesheets[all][] = descartes-style.css
stylesheets[all][] = new.css
Otherwise the subtheme will not inherit style.css from bluemarine.

Errata type: Technical | Page number: 79

Last paragraph refers to "one for the right region" for two column layout, should refer to "left region"

Errata type: Language | Page number: 79

In the NOTE "CSS and the left and right regions" there is a line which reads "We styled these while developing our CSS-only theme earlier", it should read "We styled these while developing our CSS theme earlier"

Errata type: Technical | Page number: 79

The author has written "sell" instead of "cell" in the paragraph after code:- Each "sell" corresponds to a region: left, content, and right.

Errata type: Technical | Page number: 81

The first line should read: "If we look at the home page", not "if we look at the site".

Errata type: Technical | Page number: 85 | Errata date: 18 Dec 08

The second sentence in the second-to-last paragraph begins:
Invoking theme('images', $a, $b) causes...
It should read:
Invoking theme('image', $a, $b) causes...

Errata type: Typo | Page number: 87

The first word of the first sentence after the css script should "The" and not "These"

Errata type: Technical | Page number: 88

In the section "template.php Gotchas", it is written that you can override a function only once. The function 'phptemplate_breadcrumb()' has been used as an example. However, it is not true; use the function 'descartes_breadcrumb()' instead.

Errata type: Code | Page number: 101

The code on page 101 was written to exhibit the basics of Drupal DB code. However, it could be rewritten to take advantage of more specialized aspects of the database API. Instead of using a LIMIT clause in the SQL (which is not portable across various databases), we should use the db_query_range() function. Since the returned entry will have no more than one row with one column, we could use db_result() instead of db_fetch_object(). In the example, that will return the NID (Node ID).

Errata type: Code | Page number: 106

The code sample at the top of the page should be,
return array(
'theme_a' => array(/* settings */),
'theme_b' => array(/* settings */),
'theme_c' => array(/* settings */),
);
All three lines should end in commas instead of semicolons.

Errata type: Technical | Page number: 113

In the fifth paragraph, "philqyotes" should be "philquotes".

Errata type: Code | Page number: 114

stylesheet[all][] = philquotes.css
should be stylesheets[all][]

Errata type: Technical | Page number: 134

In the paragraph starting with "Note that the registered..." in one of the parentheses you have "http://localhost/drupal/q=philquotes.json" this should be "http://localhost/drupal/?q=philquotes.json" notice the question mark.

Errata type: Code | Page number: 167

In the code example, the method 'emailusers_mail' states:
$my_account = user_current_load(null);
it should be:
$my_account = user_load(null);

Errata type: Code | Page number: 167

In the code snippet, the method named 'user_current_load()' should be 'user_current_self()'

Errata type: Code | Page number: 173

In the hook_mail_alter() implementation, the $message['body'] .= t($append, $args);
only works if you don't have an array for the message body already only a single string. The solution is either:
1. Append the disclaimer to the end of the message array by using
$message['body'][] = t($append, $args);
In this case the hook_mail implementation also needs to create bodies as such by using:
$message['body'][] = $params['body'];
2. Use the $message[id] variable inside the hook_mail_alter to make sure we're only appending the disclaimer to messages generated by our own module and not append it to every single outgoing mail.

Errata type: Code | Page number: 196

There is a typo in the code comment. It reads "Existing files: title ...". It should read "Existing fields: title..."

Errata type: Code | Page number: 197

There is a typo in the code. "#maxlengh" should be "#maxlength"

Errata type: Technical | Page number: 209

The update function doesn't work that way. There must be a Top of Form _submit function which gets the form and form_state parameter. Form has the new values, form_state the old values, but later in the drupal code, form_state is used to rebuild the node information before update is called. In the submit function one has to store the changed fields into the form_state array.

Errata type: Code | Page number: 239

In the fifth paragraph and comments of the example function reference, 'hook_filter_info()' should be 'hook_filter_tips()'.

Errata type: Technical | Page number: 269

In the code demonstrating the original document it says {{report name}}, it should be {{brief name}}.

Errata type: Technical | Page number: 269

In paragraph 6 it talks about the footer added by philquotes_mail_alter() which should be emailusers_mail_alter()