Form Structure
Each form is made up of any number of question groups, within each group there are any number of questions. Questions can accept free form text or present a list of options to the user. In some cases a particular answer may require additional information, this can be done using subquestions. Subquestions can be nested to any depth, i.e. a subquestion can present a set of answers, which in turn can present another subquestion with another set of answers and so on. The diagram below shows the structure of a survey:
Form Definition File
Currently a form definition file is used to define the contents of a form, in future it is envisaged that a web interface will be available to do it. To create a new form we define the content of the form using a YAML file. I decided to use YAML as it seems to be the defacto standard for Rails, its simple and has a nice hierarchical structure which suits the way forms are structured. All form definition files are assumed to be located in the /smerf directory.
The definitions within the file is space sensitive, be very careful to get this correct otherwise items will be grouped incorrectly. The structure must be as follows with items at the following levels:
smerfform
groups
questions
answers
The name of the form definition file is used to identify the form. If you change the name of the file then a new DB record will be created with the new code and all links to any history will be lost as this will be treated as a brand new form. When the system loads the form file for the very first time a new record will be created with a code that is set to the name of the file.
To create a link to display a form you can use the Standard REST Path method used for the show action passing the name of the form definition file as a parameter, for example
1 | link_to('Complete Test Smerf Form', smerf_form_url('testsmerf')) |
Defining the Form
When setting up a new form the first thing we do is define some settings for the form as a whole. Currently the following items can be defined for the form:
name: |
Name of the form (mandatory) |
welcome: |
Message displayed at the start of the form (optional) |
thank_you: |
Message displayed at the end of the form (optional) |
group_sort_order_field: |
Nominates which group field to use when sorting groups for display (mandatory) |
groups: |
Defines the question groups within the form (mandatory) |
Here is the definition for the test form included with the plugin:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 |
---
smerfform:
name: Test SMERF Form
welcome: |
<b>Welcome:</b>
Thank you for taking part in our Test survey we appreciate your
input.
<b>PRIVACY STATEMENT</b>
We will keep all the information you provide private and not share
it with anyone else....
thank_you: |
<b>Thank you for your input.</b>
Should you wish to discuss this survey please contact
Joe Bloggs
Tel. 12 345 678
e-mail <a href="\"mailto:jbloggs@xyz.com.au\"">Joe's email</a>
February 2007
group_sort_order_field: code
groups:
... |
Defining Groups
Each form is divided up into groups of questions, you must have at least one group per form. Here are the fields that are currently available when defining a group:
code: |
This code must be unique for all groups within the form as it is used to identify each group (mandatory) |
name: |
The name of the group, this is displayed as the group heading (mandatory) |
description: |
Provide more detailed description/instructions for the group (optional) |
questions: |
Defines all the questions contained within this group (mandatory) |
Here is the definition for the Personal Details group of the test form:
1 2 3 4 5 6 7 | personal_details:
code: 1
name: Personal Details Group
description: | This is a brief description of the Personal Details Group
here we ask you some personal details ...
questions:
... |
Defining Questions
A group can contain any number of questions, there must be at least one question per group. When defining a question you must specify the question type, the type determines the type of form field that will be created. There are currently four types that can be used, this will be expanded as needed. The current question types are:
multiplechoice: |
Allows the user to select all of the answers that apply from a list of possible choices, check boxes are used for this question type as multiple selections can be made |
singlechoice: |
Allows the user to select one answer from a list of possible choices, radio buttons are used for the question type as only a single answer can be selected |
textbox: |
Allows the user to enter a large amount of free text, the size of the text box can be specified |
textfield: |
Allows the user to enter a small amount of free form text, the size of the text field can be specified |
selectionbox: |
Allows the user to select one or more answers from a dropdown list of possible choices |
The following fields can be used to define a question:
code: |
Unique code that will identify the question, the code must be unique within a form (mandatory) |
type: |
Specifies the type of field that should be constructed on the form for this question, see above list for current types (mandatory) |
question: |
The text of the question, this field is optional as subquestions do not have to have question text |
textbox_size: |
Specifies the size of the text box to construct, rows x cols, defaults to 30x5 (optional) |
textfield_size: |
Specified the size of the text field that should be constructed, specified in the number of visible characters, default to 30 (optional) |
header: |
Specifies a separate heading for the question. The text will be displayed above the question allowing questions to be broken up into subsections (optional) |
sort_order: |
Specifies the sort order for the question |
help: |
Help text that will be displayed below the question |
answers: |
Defines the answers to the question if the question type displays a list of possibilities to the user |
validation: |
Specifies the validation methods (comma separated) that should be executed for this question, see Validation and Errors section for more details |
selectionbox_multiplechoice: |
Specifies if the selection box should allow multiple choices |
Below is an example question definition:
1 2 3 4 5 6 7 8 9 | questions:
specify_your_age:
code: g1q1
type: singlechoice
sort_order: 1
question: | Specify your ages
help: | Select the <b>one</b> that apply
validation: validate_mandatory_question
... |
Defining Answers
If the question presents a list of possible answers to the user then we can easily define these answers by using the following fields:
code: |
Code to uniquely identify the answer, code needs to be unique for each question (mandatory). The value specified here will be saved as the users response when the answer is selected. |
answer: |
The text that will be displayed to the user (mandatory) |
default: |
If set to Y then this answer will be selected by default (optional) |
sort_order: |
The sort order for this answer (mandatory) |
subquestions: |
Some answers may need additional information, another question can be defined to obtain this information. To define a subquestion the same fields that define a normal question is used (optional) |
Here is an example answer definition:
1 2 3 4 5 6 7 | answers:
1_20:
code: 1
answer: | 1-20
sort_order: 1
default: N
... |
Defining Subquestions
Additional questions can be defined for an answer if more information is required if the user selects the answer. For example you may have an answer ‘Other’ that requires additional information from the user. A subquestion can be defined for the ‘Other’ answer that takes an additional input from the user. To define a subquestion you use the same fields as for a normal question (Refer to the Defining Question section above).
Below is an example subquestion definition:
1 2 3 4 5 6 7 8 9 10 | subquestions:
other_industries:
code: g1q3a4s1
type: textbox
sort_order: 1
question:
help: | Please specify
textbox_size: 30x3
validation: validate_sub_question
... |
Data Store
There are three tables used by SMERF:
smerf_forms: |
contains details about each form |
smerf_forms_users: |
contains a record for each of the forms a user completes |
smerf_responses: |
contains a record for each response given to each question on the form. This allows analysis of answers via SQL queries. |
When a user selects to view a form the system checks the form definition file to see if any changes have been made since the last time the form was loaded, if it has the form definition file is processed and validated. A set of classes and objects are created that describes the form including SmerfFile, SmerfGroup, SmerfQuestion, SmerfAnswer, these are serialized to YAML format and stored in a single database field within the smerf_forms table. If no changes have been made to the definition file then the form is simply read from the smerf_forms table and unserialized from YAML with all classes and objects reconstructed.
The users responses to questions on a form are stored in the smerf_responses table which stores a separate record for each response to a question. If a question has multiple answers then multiple records will be created for the question. Responses for a question can be found by using the unique question code assigned within the form definition file. So for example if we had a question with code ‘g1q1′ and the user selects two answers which have been assigned code values 3 and 5 then two records will be created, i.e.
g1q1, 3
g1q1, 5
Check your DB or the migration file to see the table and column definitions for each table.
Validation and Errors
All validations are specified as part of the question (or subquestion) definition using the ‘validation:’ field. The SMERF validation system is very flexible and allows any number of validation methods to be specified for a question by comma separating each method.
1 | validation: validate_mandatory_question, validate_years |
Currently there are two validation methods provided with the plugin:
validate_mandatory_question: |
This method will ensure that the user has answered the question |
validate_sub_question: |
Only applies to subquestions and makes sure that the user has selected the answer that relates to the subquestion, it will also ensure the subquestion has been answered if the answer that relates to the subquestion has been selected. |
SMERF also allows you to define your own custom validation methods. During the installation process SMERF creates a helper module called smerf_helpers.rb in the /lib directory. You can add new validation methods into this module and access them by simply referencing them in the form definition file. For example we have question ‘How many years have you worked in the industry’ and we want to ensure that the answer provided is between 0-99 we can create a new validationmethod called ‘validate_years’.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 | # Example validation method for "How many years have you worked in the industry" # it uses a regex to make sure 0-99 years specified. # def validate_years(question, responses, form) # Validate entry and make sure years are numeric and between 0-99 answer = smerf_get_question_answer(question, responses) if (answer) # Expression will return nil if regex fail, also check charcters # after the match to determine if > 2 numbers specified res = ("#{answer}" =~ /\d{1,2}/) return "Years must be between 0 and 99" if (!res or $'.length() > 0) end return nil end |
Note: There are some helper methods that you can use within these methods included in the smerf_system_helpers.rb module which you can find in the plugins lib directory.
Your question definition may then look like this:
1 2 3 4 5 6 7 8 9 | how_many_years:
code: g2q3
type: textfield
sort_order: 3
header:
question: | How many years have you worked in the industry
textfield_size: 10
validation: validate_mandatory_question, validate_years
help: |
When the form is validated your custom validation method will be called. When an error is detected, a summary of the errors are displayed at the top of the form, additionally an error message is displayed for each question that has an error. This makes it very easy for the user to see which question they need to fix.
Complete Example
Here is the complete form definition file for the test form included with the plugin:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 | ---
smerfform:
name: Test SMERF Form
welcome: |
<b>Welcome:</b>
Thank you for taking part in our Test survey we appreciate your
input.
<b>PRIVACY STATEMENT</b>
We will keep all the information you provide private and not share
it with anyone else....
thank_you: |
<b>Thank you for your input.</b>
Should you wish to discuss this survey please contact
Joe Bloggs
Tel. 12 345 678
e-mail <a href="\"mailto:jbloggs@xyz.com.au\"">Joe's email</a>
February 2007
group_sort_order_field: code
groups:
personal_details:
code: 1
name: Personal Details Group
description: | This is a brief description of the Personal Details Group
here we ask you some personal details ...
questions:
specify_your_age:
code: g1q1
type: singlechoice
sort_order: 1
question: | Specify your ages
help: | Select the <b>one</b> that apply
validation: validate_mandatory_question
answers:
1_20:
code: 1
answer: | 1-20
sort_order: 1
default: N
21_40:
code: 2
answer: | 21_40
sort_order: 2
default: N
>40:
code: 3
answer: | > 40
sort_order: 3
default: N
subquestions:
>40:
code: g1q1a3s1
type: singlechoice
sort_order: 1
question: | Are you aged over 40
help: | Select the <b>one</b> that apply
validation: validate_sub_question
answers:
41_50:
code: 1
answer: | 41-50
sort_order: 1
default: N
51_60:
code: 2
answer: | 51_60
sort_order: 2
default: N
>61:
code: 3
answer: | > 61
sort_order: 3
default: N
subquestions:
>61:
code: g1q1a3s1a3s1
type: textfield
sort_order: 1
header:
question: | If you are older than 61, please specify
textfield_size: 10
validation: validate_sub_question
are_you_married:
code: g1q2
type: singlechoice
sort_order: 2
question: | Are you married
help:
answers:
no:
code: 1
answer: | No
sort_order: 1
default: Y
yes:
code: 2
answer: | Yes
sort_order: 2
default: N
hobbies:
code: g1q3
type: multiplechoice
sort_order: 3
question: | What are your hobbies
help: | Mark <b>all</b> that apply
header: Another header that you can group questions under
answers:
chess:
code: 1
answer: | Chess
sort_order: 1
default: N
woodwork:
code: 2
answer: | Wood work
sort_order: 2
default: N
sleeping:
code: 3
answer: | Sleeping
sort_order: 3
default: N
other:
code: 4
answer: | Other
sort_order: 4
default: N
subquestions:
other_industries:
code: g1q3a4s1
type: textbox
sort_order: 1
question:
help: | Please specify
textbox_size: 30x3
validation: validate_sub_question
employment_details:
code: 2
name: | Employment Details Group
description: | Brief description of the employment details group
question_sort_order_field: sort_order
questions:
which_industry:
code: g2q1
type: multiplechoice
sort_order: 1
question: | Which industries have you worked in
help: | Mark <b>all</b> that apply
validation: validate_mandatory_question
answers:
it:
code: 1
answer: | Information Technology
sort_order: 1
default: N
accounting:
code: 2
answer: | Accounting
sort_order: 2
default: N
finance:
code: 3
answer: | Finance
sort_order: 3
default: N
other:
code: 4
answer: | Other
sort_order: 4
default: N
subquestions:
other_industries:
code: g2q1a4s1
type: textbox
sort_order: 1
question:
help: | Please specify
textbox_size: 30x3
validation: validate_sub_question
how_many_years:
code: g2q3
type: textfield
sort_order: 3
header:
question: | How many years have you worked in the industry
textfield_size: 10
validation: validate_mandatory_question, validate_years
help: |
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