adi_contact – Form field validation & spam prevention

This plugin is used in conjunction with zem_contact_reborn to provide the following functionality:

submitted field combination check
submitted field content validation
anti-spam measures

Once installed, a collection of new tags are available:

adi_contact_combo – define valid combinations of submitted form fields
adi_contact_validate – validate the content of submitted form fields
adi_contact_spam – block spam in submitted form fields
adi_contact_labels – specify labels to be used in error messages

Use the above tags within a <txp:zem_contact> ... </txp:zem_contact> container. A full example of usage is provided at the end.

Form field combinations (adi_contact_combo)

Sometimes certain combinations of form fields are required from users, for example:

fill in at least one of “Likes”, “Dislikes”, “Other comments”
if “Phone number” is filled in then “Best time to call” is also required

For example to make sure the user fills in at least one field in a specified list:

<txp:zem_contact>
  ...
  <txp:zem_contact_textarea name="likes" label="Likes" required="0" />
  <txp:zem_contact_textarea name="dislikes" label="Dislikes" required="0" />
  <txp:zem_contact_textarea name="comments" label="Other comments" required="0" />
  <txp:adi_contact_combo names="likes,dislikes,comments"
    restrict="min" number="1" />
</txp:zem_contact>

Or if an extra field has to be filled in:

<txp:zem_contact>
  ...
  <txp:zem_contact_text name="phone" label="Your phone number"
    required="0" />
  <txp:zem_contact_text name="when" label="When should we call you?"
    required="0" />
  <txp:adi_contact_combo names="phone" require="when" />
</txp:zem_contact>

You can also generate custom error messages by using required="0" in the standard ZCR tags and required="1" in adi_contact_combo. For example:

<txp:zem_contact>
  ...
  <txp:zem_contact_text name="name" label="Name" required="0" />
  <txp:adi_contact_combo names="name" required="1" message="Don't be shy!"/>
</txp:zem_contact>

No real magic here – required="1" is actually the equivalent of restrict="equal" number="1".

adi_contact_combo – attributes

names="name list"

- comma separated list of field names that are of interest. Default = “” (none).

restrict="restriction"

- defines a minimum (min), a maximum (max), or an exact number (equal),

number="integer"

- number of fields, used in conjunction with restrict.

require="name list"

- comma separated list of field names that are required, depending on the presence of fields in names list.

required="boolean”

- the specified field is required (useful for creating custom error messages). Default = “0” (not required).

checkbox="boolean”

- the specified fields are checkboxes, so test for Yes/No. Default = “0” (not checkboxes).

message="text"

- alternative error message (see below for list of placeholders).

Form field validation (adi_contact_validate)

This enables the contents of fields to be validated, for example to check that a phone number field has been filled in properly:

<txp:adi_contact_validate names="home_phone" type="phone" />

adi_contact_validate – attributes

names="name list"

- comma separated list of field names that should be validated. Default = “” (none).

type="validation"

- the type of validation that is required:

alpha – alphabetic characters
alphanum – alpha-numeric characters
integer – digits only
numeric – a number (e.g. +0123.45e6 is a number)
phone – phone number (i.e. 0-9 + – . , () xX space)
url – a URL (with or without “http://”)
custom – use in conjunction with pattern

allow_whitespace="boolean"

- allow whitespace (i.e. space, tab, newlines etc) in addition to that specified in type. Default = “0” (No).

pattern="pattern string"

- a pattern that will be dropped straight into preg_match. Used in conjunction with type="custom". Default = “” (none).

message="text"

- alternative error message.

Spam prevention (adi_contact_spam)

This will prevent email header injection and stop emails that contain links (which is, after all, what spammers want to send you).

By default adi_contact_spam will check all fields, so if you want users to send you links then use the exclude attribute:

<txp:zem_contact>
  ...
  <txp:zem_contact_text name="website" label="Your website URL" />
  <txp:adi_contact_spam exclude="website" />
</txp:zem_contact>

adi_contact_spam – attributes

names="name list"

- comma separated list of field names that should be checked. Default = “” (all submitted fields).

exclude="name list"

- comma separated list of field names that should NOT be checked. Default = “” (none).

detect_mail_headers="boolean"

- detect the presence of to:, from:, bcc:, multipart, cc:, Content-Transfer-Encoding:, Content-Type:, Mime-Version: and flag as spam if found. Default = “1” (Yes).

detect_link_tags="boolean"

- detect the presence of [url, http, www, href and flag as spam if found. Default = “1” (Yes).

allow_www="boolean"

- allow the presence of www and do not flag as spam. Default = “0” (No).

message="text"

- alternative error message.

Error messages, labels and styling (adi_contact_labels & the ‘message’ attribute)

The ‘message’ attribute

The adi_contact tags will generate standard messages in English. The messages can be customised by using the message="" attribute:

alter the standard message
translate the standard message into other languages
use [NAMES] (‘names’ attribute), [REQUIRE] (‘require’ attribute) & [NUMBER] (‘number’ attribute) placeholders

The adi_contact error messages are placed in the same list as the standard zem_contact error messages.

adi_contact_labels – attributes

name1="label string 1" name2="label string 2"

- the labels to use in adi_contact error messages.

Important: The adi_contact_labels tag MUST be placed in the page/form before other adi_contact tags – otherwise your label strings won’t be picked up.

Example:

<txp:adi_contact_labels phone="Phone number" when="When to call"
  likes="Likes" dislikes="Dislikes" comments="Comments" />

Notes:

a label specified with adi_contact_labels does not have to match the actual label used in the form
labels specified with adi_contact_labels are only used in adi_contact error messages
the error messages will use labels in the following order of preference:
- label specified in adi_contact_labels
- form label retrieved from zem_contact (but only if a field has been filled in & submitted)
- the field name (with first letter in upper case)

Styling

The standard zem_contact class of zemRequirederrorElement is automatically added to label and input elements when errors are found.

An extra class of adi_contact_error is also added to facilitate additional styling options.

The Full Monty Example

The following is an example of a user feedback form:

<txp:zem_contact to='me@example.com' subject='Feedback form example'>

  <p>Please fill in the form:</p>

  <-- the feedback form presented to the user -->
  <txp:zem_contact_text name="name" label="Name" />
  <txp:zem_contact_email name="email" />
  <txp:zem_contact_text name="phone" label="Your phone number" required="0" />
  <txp:zem_contact_text name="when" label="When should we call you?" required="0" />
  <txp:zem_contact_textarea name="likes" label="Likes" required="0" />
  <txp:zem_contact_textarea name="dislikes" label="Dislikes" required="0" />
  <txp:zem_contact_textarea name="comments" label="Other comments" required="0" />
  <txp:zem_contact_submit label="Send feedback" />

  <-- specify labels to be used in error messages -->
  <txp:adi_contact_labels phone="Phone number" when="When to call" comments="Comments" />

  <-- at least one of "likes,dislikes,comments" required -->
  <txp:adi_contact_combo names="likes,dislikes,comments" restrict="min" number="1" />

  <-- if "phone" supplied then "when" required as well; include custom error message -->
  <txp:adi_contact_combo names="phone" require="when"
    message="You've only given me [NAMES] but I need to know [REQUIRE] too" />

  <-- validate the phone number -->
  <txp:adi_contact_validate names="phone" type="phone" />

  <-- check for spam but allow user to send simple "www." URLs -->
  <txp:adi_contact_spam allow_www="1" />

</txp:zem_contact>

Notes:

the <txp:adi_contact_labels /> tag is placed before the other adi_contact tags
only the labels for phone, when & comments are specified because they are different from the actual form labels

Additional information

Support and further information can be obtained from the Textpattern support forum. A copy of this help is also available online. More adi_plugins can be found here.

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adi_contact – Form field validation & spam prevention

Form field combinations (adi_contact_combo)

adi_contact_combo – attributes

Form field validation (adi_contact_validate)

adi_contact_validate – attributes

Spam prevention (adi_contact_spam)

adi_contact_spam – attributes

Error messages, labels and styling (adi_contact_labels & the ‘message’ attribute)

The ‘message’ attribute

adi_contact_labels – attributes

Styling

The Full Monty Example

Notes:

Additional information

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