need / req (or any other defined need type)

Creates a need object with a specified type. You can define the type using the correct directive, like .. req:: or .. test::.

Example

.. req:: User needs to login
   :id: ID123
   :status: open
   :tags: user;login
   :collapse: false

   Our users needs to get logged in via our login forms on **/login.php**.

Output

Requirement: User needs to login ID123 ../_images/arrow-right-circle.svg
status: open
tags: user, login

Our users needs to get logged in via our login forms on /login.php.

The code example above creates a new requirement, with a title, content, given id, a status and several tags.

All the options for the requirement directive ( req ) are optional, but you must set a title as an argument (i.e. if you do not specify needs_title_from_content in the conf.py file).

Note

By default, the above example works also with .. spec::, .. impl::, .. test:: and all other need types, which are configured via needs_types.

Variants for options support

New in version 1.0.2.

Needs variants add support for variants handling on need options.
The support for variants options introduce new ideologies on how to set values for need options.

To implement variants options, you can set a need option to a variant definition or multiple variant definitions. A variant definition can look like var_a:open or ['name' in tags]:assigned.

A variant definition has two parts: the rule or key and the value.
For example, if we specify a variant definition as var_a:open, then var_a is the key and open is the value. On the other hand, if we specify a variant definition as ['name' in tags]:assigned, then ['name' in tags] is the rule and assigned is the value.

Rules for specifying variant definitions

  • Variants gets checked from left to right.

  • When evaluating a variant definition, we use data from the current need object, Sphinx-Tags, and needs_filter_data as the context for filtering.

  • You can set a need option to multiple variant definitions by separating each definition with either the , or ; symbol, like var_a:open; ['name' in tags]:assigned.|br| With multiple variant definitions, we set the first matching variant as the need option’s value.

  • When you set a need option to multiple variant definitions, you can specify the last definition as a default “variant-free” option which we can use if no variant definition matches.
    Example; In this multi-variant definitions, [status in tags]:added; var_a:changed; unknown, unknown will be used if none of the other variant definitions are True.

  • If you prefer your variant definitions to use rules instead of keys, then you should put your filter string inside square brackets like this: ['name' in tags]:assigned.

  • For multi-variant definitions, you can mix both rule and variant-named options like this: [author["test"][0:4] == 'me']:Me, var_a:Variant A, Unknown

To implement variants options, you must configure the following in your conf.py file:

There are various use cases for variants options support.

Use Case 1

In this example, you set the needs_variants configuration that comprises pre-defined variants assigned to “filter strings”. You can then use the keys in your needs_variants as references when defining variants for a need option.

Example

In conf.py:

needs_variants = {
  "var_a": "'var_a' in sphinx_tags"  # filter_string
  "var_b": "assignee == 'me'"
}

In your .rst file:

.. req:: Example
   :id: VA_001
   :status: var_a:open, var_b:closed, unknown

From the above example, if a need option has variants defined, then we get the filter string from our needs_variants configuration and evaluate it. If a variant definition is true, then we set the need option to the value of the variant definition.

Use Case 2

In this example, you can use the filter string directly in the need option’s variant definition.

Example

In your .rst file:

.. req:: Example
   :id: VA_002
   :status: ['var_a' in tags]:open, [assignee == 'me']:closed, unknown

From the above example, we evaluate the filter string in our variant definition without referring to needs_variants. If a variant definition is true, then we set the need option to the value of the variant definition.

Use Case 3

In this example, you can use defined tags (via the -t command-line option or within conf.py, see here) in the need option’s variant definition.

Example

First of all, define your Sphinx-Tags using either the -t command-line sphinx-build option:

sphinx-build -b html -t tag_a . _build

or using the special object named tags which is available in your Sphinx config file (conf.py file):

tags.add("tag_b")   # Add "tag_b" which is set to True

In your .rst file:

.. req:: Example
   :id: VA_003
   :status: [tag_a and tag_b]:open, closed

From the above example, if a tag is defined, the plugin can access it in the filter context when handling variants. If a variant definition is true, then we set the need option to the value of the variant definition.

Note

Undefined tags are false and defined tags are true.

Below is an implementation of variants for need options:

Example

.. req:: Variant options
   :id: VA_004
   :status: ['variants' in tags and not collapse]:enabled, disabled
   :tags: variants;support
   :collapse: true

   Variants for need options in action

Result

Requirement: Variant options VA_004 ../_images/arrow-right-circle.svg
status: disabled
tags: variants, support

Variants for need options in action

Diagram support

A need objects can also define it’s own PlantUML representation. Therefore Sphinx-Needs looks for the needuml directive inside the content and stores its PlantUML code under given key from needuml directive under the option name arch.

This diagram data can then be used in other needuml calls to combine and reuse PlantUML elements.

Example

.. spec:: Interfaces
   :id: SP_INT
   :status: open

   This are the provided interfaces:

   .. needuml::

      circle "Int A" as int_a
      circle "Int B" as int_b
      circle "Int C" as int_c

Reuse of :need:`SP_INT` inside a :ref:`needuml`:

.. needuml::

   allowmixing

   {{uml("SP_INT")}}
   node "My System" as system

   system => int_a

Result

Specification: Interfaces SP_INT ../_images/arrow-right-circle.svg
status: open

This are the provided interfaces:

@startuml

circle "Int A" as int_a
circle "Int B" as int_b
circle "Int C" as int_c
@enduml

Reuse of Interfaces (SP_INT) inside a needuml:

@startuml

allowmixing

circle "Int A" as int_a
circle "Int B" as int_b
circle "Int C" as int_c
node "My System" as system

system => int_a
@enduml

This simple mechanism is really powerful to design reusable and configurable SW architecture diagrams. For more examples and details, please read needuml.

Filter for diagrams

The option arch can be easily used for filtering. For instance to show all need objects, which are representing some kind of a diagram.

Example

.. needtable::
   :filter: bool(arch)
   :style: table
   :columns: id, type, title

Result

ID

Type

Title

COMP_001

comp

Component X

COMP_002

comp

Component Y

COMP_A_B

comp

Variant A or B

COMP_NEEDUML2

comp

NeedUml example need 2

COMP_T_001

comp

COMP_T_001

COMP_T_002

comp

COMP_T_002

COMP_T_003

comp

COMP_T_003

COMP_X

comp

Component X

COMP_Z

comp

Z

INT_001

int

Test needuml save

INT_A

int

Interface A

req_arch_001

req

Requirement arch

req_arch_004

req

Req Arch four

SP_INT

spec

Interfaces

SYS_ROCKET

sys

System RocketScience

test_arch_001

test

Test Arch

Options for Need Type

id

The given ID must match the regular expression (regex) value for the needs_id_regex parameter in conf.py. The Sphinx build stops if the ID does not match the regex value.

If you do not specify the id option, we calculate a short hash value based on the title. The calculated value can also include title if needs_id_from_title is set to True. If you don’t change the title, the id will work for all upcoming documentation generations.

status

A need can only have one status, and the needs_statuses configuration parameter may restrict its selection.

tags

You can give multiple tags by separating each with ; symbol, like tag1;tag2;tag3. White spaces get removed.

The links option can create a link to one or several other needs, no matter the need type. All you must specify is the ID for the need.

You can easily set links to multiple needs by using ; as a separator.

Example

.. req:: Link example Target
   :id: REQ_LINK_1

   This is the target for a link. Itself has no link set.

.. req:: Link example Source
   :links: REQ_LINK_1

   This sets a link to id ``REQ_LINK_1``.

Result

Requirement: Link example Source R_262A1 ../_images/arrow-right-circle.svg
links outgoing: REQ_LINK_1

This sets a link to id REQ_LINK_1.

By using needs_extra_links, you can use the configured link-types to set additional need options.

Example

# conf.py
needs_extra_links = [
   {
      "option": "blocks",
      "incoming": "is blocked by",
      "outgoing": "blocks"
   },
   {
      "option": "tests",
      "incoming": "is tested by",
      "outgoing": "tests",
      "copy": False,
      "color": "#00AA00"
   }
]
.. req:: test me
   :id: test_req

   A requirement, which needs to be tested

.. test:: test a requirement
   :id: test_001
   :tests: test_req

   Perform some tests

Result

Requirement: test me test_req ../_images/arrow-right-circle.svg
links incoming: test_001
is tested by: test_001

A requirement, which needs to be tested

Test Case: test a requirement test_001 ../_images/arrow-right-circle.svg
links outgoing: test_req
tests: test_req

Perform some tests

delete

There is a :delete: option. If the value of the option is set to true, the need will be deleted completely from any NeedLists or NeedDicts including the needs.json file.

This option allows a user to have multiple need-objects with the same id, but only one is shown in the documentation.

If set to false, the need is not removed.

Allowed values:

  • true or yes or 1

  • false or no or 0

Default: False

Note

If you delete a need using the :delete: option, the need will not be part of any filter result.

Example

.. req:: First Requirement Need
   :id: DELID123
   :status: open
   :delete: true

   Need with ``:delete:`` equal to ``true``.

.. req:: Second Requirement Need
   :id: DELID123
   :delete: false

   Need with ``:delete:`` equal to ``false``.

   .. spec:: Nested Need without delete option
      :id: DELID124
      :tags: nested-del-need

      Need with ``:delete:`` option not set.

Result

Requirement: Second Requirement Need DELID123 ../_images/arrow-right-circle.svg
delete: False
child needs: DELID124

Need with :delete: equal to false.

Specification: Nested Need without delete option DELID124 ../_images/arrow-right-circle.svg
tags: nested-del-need
parent needs: DELID123

Need with :delete: option not set.

hide

There is a :hide: option. If this is set (no value is needed), the need will not be printed in the documentation. But you can use it with need filters.

collapse

If set to True, the details section containing status, links or tags is not visible. You can view the details by clicking on the forward arrow symbol near the need title.

If set to False, the need shows the details section.

Allowed values:

  • true; yes; 1

  • false; no; 0

Default: False

Example

.. req:: Collapse is set to True
   :tags: collapse; example
   :collapse: True

   Only title and content are shown

.. req:: Collapse is set to False
   :tags: collapse; example
   :collapse: False

   Title, tags, links and everything else is shown directly.

Result

Requirement: Collapse is set to True R_A2D07 ../_images/arrow-right-circle.svg
tags: collapse, example

Only title and content are shown

Requirement: Collapse is set to False R_316DE ../_images/arrow-right-circle.svg
tags: collapse, example

Title, tags, links and everything else is shown directly.

jinja_content

The option activates jinja-parsing for the content of a need. If the value is set to true, you can specify Jinja syntax in the content.

The :jinja_content: option give access to all need data, including the original content and the data in needs_filter_data.

If you set the option to False, you deactivate jinja-parsing for the need’s content.

Allowed values:

  • true or yes or 1

  • false or no or 0

Default: False

Note

You can set the :jinja_content: option using the needs_global_options configuration variable. This will enable jinja-parsing for all the need objects in your documentation project.

needs_global_options = {
  'jinja_content': 'true'
}

Example

.. req:: First Req Need
   :id: JINJAID123
   :jinja_content: false

   Need with ``:jinja_content:`` equal to ``false``.

   .. spec:: Nested Spec Need
      :id: JINJAID125
      :status: open
      :tags: user;login
      :links: JINJAID126
      :jinja_content: true

      Nested need with ``:jinja_content:`` option set to ``true``.
      This requirement has tags: **{{ tags | join(', ') }}**.

      It links to:
      {% for link in links %}
      - {{ link }}
      {% endfor %}


.. spec:: First Spec Need
   :id: JINJAID126
   :status: open
   :jinja_content: true

   Need with ``:jinja_content:`` equal to ``true``.
   This requirement has status: **{{ status }}**.

Result

Requirement: First Req Need JINJAID123 ../_images/arrow-right-circle.svg
jinja_content: False
child needs: JINJAID124

Need with :jinja_content: equal to false.

Specification: Nested Spec Need JINJAID124 ../_images/arrow-right-circle.svg
status: open
tags: user, login
jinja_content: True
links outgoing: JINJAID126
parent needs: JINJAID123

Nested need with :jinja_content: option set to true. This requirement has tags: user, login.

It links to:

  • JINJAID126

Specification: First Spec Need JINJAID126 ../_images/arrow-right-circle.svg
status: open
jinja_content: True
links incoming: JINJAID124

Need with :jinja_content: equal to true. This requirement has status: open.

title_from_content

New in version 0.2.3.

When this flag is provided on a need, a title will be derived from the first sentence of the content. If the title or content is not provided then the build process will fail.

The derived title will respect the needs_max_title_length and provide an elided title if needed. By default there is no limit to the title length.

Note

When using this setting ensure that the first sentence does not contain any special formatting you would not want in the title (bulleted lists, nested directives, etc.)

If a title is provided and the flag is present, then the provided title will be used and a warning will be issued.

Example

.. req::
   :title_from_content:

   The first sentence will be the title.  Anything after the first
   sentence will not be part of the title.

Result

The resulting requirement would have the title derived from the first sentence of the requirement.

Requirement: The first sentence will be the title R_BAFCF ../_images/arrow-right-circle.svg

The first sentence will be the title. Anything after the first sentence will not be part of the title.

layout

New in version 0.4.1.

layout can be used to set a specific grid and content mapping.

Example

.. req:: My layout requirement 1
   :id: LAYOUT_1
   :tags: layout_example
   :layout: clean

   Some **content** of LAYOUT_1

Result

Requirement: My layout requirement 1 LAYOUT_1 ../_images/arrow-right-circle.svg
tags: layout_example
layout: clean

Some content of LAYOUT_1

Example

.. req:: My layout requirement 2
   :id: LAYOUT_2
   :tags: layout_example
   :layout: complete

   Some **content** of LAYOUT_2

Result

My layout requirement 2
Requirement
tags: layout_example

Some content of LAYOUT_2

Example

.. req:: My layout requirement 3
   :id: LAYOUT_3
   :tags: layout_example
   :layout: focus

   Some **content** of LAYOUT_3

Result

Some content of LAYOUT_3

Please take a look into Layouts for more information.

style

New in version 0.4.1.

style can be used to set a specific class-attribute for the need representation.

The class-attribute can then be selected with CSS to specify the layout of the need.

Examples

Requirement: My styled requirement STYLE_001 ../_images/arrow-right-circle.svg
tags: style_example
style: red
Requirement: Another styled requirement STYLE_002 ../_images/arrow-right-circle.svg
tags: style_example
style: blue
Requirement: Green is my color STYLE_003 ../_images/arrow-right-circle.svg
tags: style_example
style: green
Requirement: Yellow and blue border STYLE_004 ../_images/arrow-right-circle.svg
style: yellow, blue_border
.. req:: My styled requirement
   :id: STYLE_001
   :tags: style_example
   :style: red

.. req:: Another styled requirement
   :id: STYLE_002
   :tags: style_example
   :style: blue

.. req:: Green is my color
   :id: STYLE_003
   :tags: style_example
   :style: green

.. req:: Yellow and blue border
   :id: STYLE_004
   :style: yellow, blue_border

By using Dynamic functions, the value of style can be automatically derived from the values of other need options.

Here style is set to [[copy('status')]], which leads to the CSS class needs_style_open if the status option is set to open.

Examples

Requirement: My automatically styled requirement STYLE_005 ../_images/arrow-right-circle.svg
status: implemented
tags: style_example
style: implemented
Requirement: My automatically styled requirement STYLE_006 ../_images/arrow-right-circle.svg
status: open
tags: style_example
style: open
.. req:: My automatically styled requirement
   :id: STYLE_005
   :status: implemented
   :tags: style_example
   :style: [[copy(status)]]

.. req:: My automatically styled requirement
   :id: STYLE_006
   :status: open
   :tags: style_example
   :style: [[copy(status)]]

template

New in version 0.5.2.

By setting template, the content of the need gets replaced by the content of the specified template.

Sphinx-Needs templates support the Jinja templating language and give access to all need data, including the original content.

The template name must be equal to the filename in the Sphinx-Needs template folder, without the file extension. For example, if the filename is my_template.need, you can reference it like this: :template: my_template. Sphinx-Needs templates must have the file extension .need.

You can specify the location of all template files by configuring the needs_template_folder, which is by default needs_templates/, in the conf.py file.

You can have several templates, but can set only one for a need.

Example

Template: spec_template.need

{# Comment, no output here #}
A line before the content

{# Place the original content here #}
{{content}}

{# Use {{..}} to access need values #}
Status: **{{status}}**

Template: **{{template}}.need**

{# You can also loop over need values #}
Tags:
{% for tag in tags %}
{{loop.index}}. tag: **{{tag}}**
{% endfor %}

{# Access to values from other needs can be done #}
{# by using dynamic_functions #}
Links:
{% for link in links %}
| **{{link}}**: [[copy('title', '{{link}}')]] ([[copy('type_name', '{{link}}')]])
{%- endfor %}

Need

.. spec:: My specification
   :status: open
   :links: FEATURE_1, FEATURE_2
   :id: TEMPL_SPEC
   :tags: example, template
   :template: spec_template

   This is my **specification** content.

Result

Specification: My specification TEMPL_SPEC ../_images/arrow-right-circle.svg
status: open
tags: example, template
template: spec_template
links outgoing: FEATURE_1, FEATURE_2

A line before the content

This is my specification content.

Status: open

Template: spec_template.need

Tags:

  1. tag: example

  2. tag: template

Links:

FEATURE_1: Filtering needs (Feature)
FEATURE_2: Ex/Importing needs (Feature)

You can find a list of need-value names in the documentation for Filter string or by using the debug layout.

You can automatically assign templates to specific needs by using needs_global_options.

Multiline options

In Sphinx, options support multi-line content, which you can interpret like other RST input in Sphinx-Needs templates.

But there is one important constraint: Don’t use empty lines, as we use them in defining the content end. Instead, you can use __ (two underscores) to define the content end and can use | to force line breaks.

Example

Need

.. req:: A really strange example
   :id: multiline_1234
   :status:
     | First line
     | Second line
     | Followed by an empty line
     __
     A list example:
     __
     * take *this*
     * and **this**
     __
     __
     __
     3 new lines, but 1 is shown only
     __
     Included directives
     __
     .. req:: test req
        :id: abc_432
        __
        This works!
        __
        An image: wow
        __
        .. image:: /_images/needs_logo.png
           :width: 20%
     __
     .. image:: /_images/needs_logo.png
        :width: 30%
   :template: content

Template

{{status}}

Result

Requirement: A really strange example multiline_1234 ../_images/arrow-right-circle.svg
status: | First line | Second line | Followed by an empty line A list example: * take *this* * and **this** 3 new lines, but 1 is shown only Included directives .. req:: test req :id: abc_432 This works! An image: wow .. image:: /_images/needs_logo.png :width: 20% .. image:: /_images/needs_logo.png :width: 30%
template: content
child needs: abc_432
First line
Second line
Followed by an empty line

A list example:

  • take this

  • and this

3 new lines, but 1 is shown only

Included directives

Requirement: test req abc_432 ../_images/arrow-right-circle.svg
parent needs: multiline_1234

This works!

An image: wow

../_images/needs_logo.png
../_images/needs_logo.png

pre_template

New in version 0.5.4.

Adds specific content from a template before a need. For example, you can use it to set a section name before each need.

Example

Template: spec_pre_template.need

**{{title}}**

Ohh nice we got a bold written "title" before our need.

Need

.. spec:: My specification
   :id: TEMPL_PRE_SPEC
   :tags: example, template
   :pre_template: spec_pre_template

   This is my **specification** content.

Result

My specification

Ohh nice we got a bold written “title” before our need.

Specification: My specification TEMPL_PRE_SPEC ../_images/arrow-right-circle.svg
tags: example, template
pre_template: spec_pre_template

This is my specification content.

post_template

New in version 0.5.4.

Adds specific content from a template after a need. You can use it to show some need-specific analytics, like dependency diagrams or table of linked needs.

Example

Template: spec_post_template.need

**Analytics for above need:** {{title}}

.. needflow::
   :filter: id == '{{id}}' or '{{id}}' in links_back

Need

.. spec:: My specification
   :id: TEMPL_POST_SPEC
   :tags: example, template
   :links: FEATURE_1, FEATURE_2
   :post_template: spec_post_template

   This is my **specification** content.

Result

Specification: My specification TEMPL_POST_SPEC ../_images/arrow-right-circle.svg
tags: example, template
post_template: spec_post_template
links outgoing: FEATURE_1, FEATURE_2

This is my specification content.

Analytics for above need: My specification

@startuml

' Nodes definition 

node "<size:12>Specification</size>\n**My**\n**specification**\n<size:10>TEMPL_POST_SPEC</size>" as TEMPL_POST_SPEC [[../directives/need.html#TEMPL_POST_SPEC]] #FEDCD2
node "<size:12>Feature</size>\n**Filtering needs**\n<size:10>FEATURE_1</size>" as FEATURE_1 [[../index.html#FEATURE_1]] #FFCC00
node "<size:12>Feature</size>\n**Ex/Importing**\n**needs**\n<size:10>FEATURE_2</size>" as FEATURE_2 [[../index.html#FEATURE_2]] #FFCC00

' Connection definition 

TEMPL_POST_SPEC --> FEATURE_1
TEMPL_POST_SPEC --> FEATURE_2

@enduml

duration

New in version 0.5.5.

Track the duration of a need.

The need allows any value but the needgantt directive uses and interprets it as days by default.

completion

New in version 0.5.5.

Track the completion of a need.

The need allows any value but the needgantt directive uses and interprets it as percentage by default.

Customized Options

Sphinx-Needs supports the definition and filtering of customized options for needs.

You can read needs_extra_options for detailed information and examples.

Removed Options

Note

To remove options from the Sphinx-Needs output in versions >= 0.5.0, you must provide your own layout, which does not include these options. See Layouts & Styles for more information.

hide_status

removed: 0.5.0

Hide the status information of a need.

hide_tags

removed: 0.5.0

Hide the tags of a need.