silverstripe / silverstripe-docsviewer

Documentation generator that powers doc.silverstripe.org and your own projects

Documentation Viewer Module

ABANDONED

This package is abandoned. See silverstripe/doc.silverstripe.org instead.

Maintainer Contact

• Will Rossiter (Nickname: willr, wrossiter) [email protected]

Requirements

These are pulled in via Composer.

• SilverStripe 3.1
• Parsedown and Parsedown Extra.

Summary

Reads markdown files from a given list of folders from your installation and provides a web interface for viewing the documentation. Ideal for providing documentation alongside your module or project code.

A variation of this module powers the main SilverStripe developer documentation and the user help websites.

For more documentation on how to use the module please read /docs/Writing-Documentation.md (or via this in /dev/docs/docsviewer/Writing-Documentation in your webbrowser)

Installation

composer require "silverstripe/docsviewer" "dev-master"

Usage

After installing the files via composer, rebuild the SilverStripe database..

sake dev/build

Then start by viewing the documentation at yoursite.com/dev/docs.

If something isn't working, you can run the dev task at yoursite.com/dev/tasks/CheckDocsSourcesTask to automatically check for configuration or source file errors.

Out of the box the module will display the documentation files that have been bundled into any of your installed modules. To configure what is shown in the documentation viewer see the detailed documentation.

For more information about how to use the module see each of the documentation

* [Configuration](docs/en/configuration.md)
* [Markdown Syntax](docs/en/markdown.md)
* [Syntax Highlighting](docs/en/syntax-highlighting.md)
* [Publishing Static Files](docs/en/statichtml.md)

License

See LICENSE

silverstripe-docsviewer's Issues

Numerical pages should be sorted as numerics not strings

Reported by Luke Percy over in the docs.silverstripe.org repo.

"The versioning order on http://doc.silverstripe.org/en/changelogs/ doesn't look right.
3.1.12 is the latest to my understanding (then RC,Alpha,Beta etc.), but the ordering on that list puts it below 3.1.9 this can be confusing to clients when reading what version is the latest."

BUG relative links are parsed incorrectly when markdown srouce folder is symlinked

When a defined src folder is set, and this folder is symlinked outside the webroot the markdown parser returns an absolute path link into the actual folder the *.md files are stored in rather than relative to the src symlink.

The outcome is in this configuration and images linked are broken.

Create alphabetical index for a module

This should span across subfolders, basically list every page in an alphabetized list - see Paul's mockup attached. Maybe even span across multiple modules.

See HTML implementation at http://open.silverstripe.org/attachment/ticket/6337/Index%20page.zip

Inline code not working in div with class "info"

Go to http://doc.silverstripe.org/en/developer_guides/configuration/configuration/
search "The name of the files within the applications", the words _config, email.yml and others in the inline code are not in the inline format. The source is as below:

<div class="info" markdown="1">
The name of the files within the applications `_config` directly are arbitrary. Our examples use 
`mysite/_config/app.yml` but you can break this file down into smaller files, or clearer patterns like `extensions.yml`, 
`email.yml` if you want. For add-on's and modules, it is recommended that you name them with `<module_name>.yml`.
</div>

However, it works for class "alert":

<div class="alert" markdown="1">
Due to YAML limitations, having multiple conditions of the same kind (say, two `EnvVarSet` in one "Only" block)
will result in only the latter coming through.
</div>

:::ss syntax parser breaks if above line has tabs

Ideal fix should allow the parser to check for these tabs and ignore them.

User edits created commits to underlying git repo

Should be able to provide a commit message.

Allows bigger doc contributions from technical writers, the repo could then be cherry picked/merged to capture more incremental documentation contributions.

Missing mobile side menu

Reported in the docs.silverstripe.org repo - silverstripe/doc.silverstripe.org#135

Currently working on a fix.

Alternatives to discuss for targeted documentation discussion

I don't think discuss really cuts the mustard, especially with documentation issues, updates and discussion. I would like to spark up a discussion about how we could improve this on our documentation. Discuss also shows old threads which are (sometimes) no longer relevant to a version etc.

One example of targeted documentation discussion is on medium (https://medium.com/php-development/64eb28781489) where a message is posted to a paragraph and can be viewed while you are reading the content rather then down the bottom of the page.

It would also be handy to mark these issues/comments once they are resolved by a community member rather then having them hang around.

Closing header tags (#, ## ... ) render out to page

Relevant pull request in Beta docs where the hashes are rendering.

Example page where the tags render in Beta SS docs.

And a screenshot:

Linking to 4.0 (master) API docs

While reviewing the Silverstripe 4 documentation I came across a link that is supposed to lead to a page on the Silverstripe 4 api docs.

The link in question tries to link to i18n::set_locale() with [api:i18n::set_locale()], but this link is invalid as the api docs for this class in 4.0 are under master, as opposed to 4.

Further digging has revelaled that the documentation is littered with these broken links

Needs 3rd party files

For this to work it needs http://parsedown.org/ and https://github.com/erusev/parsedown-extra

Upgrade to SilverStripe 4 (or don't?)

Before spending a lot of time on upgrading this module to SS4, we should resolve the discussion around moving doc.silverstripe.org to a third party documentation service: silverstripe/doc.silverstripe.org#157

While I acknowledge that docsviewer is used in other contexts, it significantly lowers our need to upgrade it if we're not using it on doc.ss.org. I see docsviewer (and the related maintenance around doc.ss.org) as a moderate distraction for SS Ltd, which could be better spent elsewhere. Our Markdown isn't that special :D

Transifex support for this module?

How come this module doesn't have Transifex configuration?

Search box on 404 page does not work

see silverstripe/doc.silverstripe.org#51

Develop branch

@SpiritLevel we had a develop branch going for docsviewer however I see your recent PRs have gone direct into master. Can you please check https://github.com/silverstripe/silverstripe-docsviewer/commits/develop and let me know if any commits here that are important are missing from master. I'd like to tidy that up and drop the develop branch as long as we have accounted for these.

Thanks.

Page sorting limitation

At the moment page sorting is done by prefixing a document with a number. If you ever want to change the order of pages or introduce a new page between existing ones you may have to rename several files which could complicate the git history and make merges difficult.

Wondering if instead of prefixing the filenames, we have a 'priority' field in addition to the 'title' and 'summary' field in each file, which could use positive and negative decimals to allow a lot more flexibility in sorting.

Update handle action to generate 'nice' urls for pages away from filename

Take a folder like 01_Somepage should generate (and match) the URL segment 'somepage' if multiple candidates for 'somepage' revert back to original.

Prev/next navigation for pages in a folder

At the bottom of each content page, you should be able to go to the next/previous topic (in the same folder).

Paul has already added CSS for the following markup:

« Previous Page | Next Page »

Rather than "previous" labels it should show the actual page title.

On the first page, we could link to the index, or "top"/up one level, on last page to the index page of next folder. Thats less important though.

More helpful 404 page (integrated search/suggestions box)

See attached screenshot of Paul's mockup, with this markup (CSS already in place):

We're sorry…

The page you are looking for might have moved, no longer exists or is not currently available.

Perhaps you could…

return to the homepage or try searching.

Search results for similar/related phrases

• Installing
• Upgrading
• Server-requirements
• Suggested-web-hosts

                    <div class="warningBoxBottom">

                        <ul>
                            <li><a href="#">Report a missing link</a></li>
                            <li><a href="#">Report a bug or a concren</a></li>
                        </ul>
                    </div>
                </div>

http://open.silverstripe.org/attachment/ticket/6344/Screen%20shot%202011-01-13%20at%208.33.33%20PM.png

Issue linking to #id within page #124

e.g. https://docs.silverstripe.org/en/3.3/changelogs/3.2.0/

If you look at the link to "Major Changes" (which points to #major-changes) it links to the current URL without the last URL segment.

Add support for README.md display in case docs/index.md is missing

This is critical for "auto detected" installations of sapphiredocs, as most modules only have a README

Nicer, more hackable search URL

Before: home/DocumentationSearchForm?Search=bbcode&action_results=Search After: /?q=bbcode

Should be possible by adding a check in index(), and overwriting the form action :) Not sure how to get rid of the button, perhaps we can do a redirect in index() as well (which would slow down search, so not ideal)

Sitemap.xml generation to prioritise latest stable docs

I find that google searches like silverstripe file often return results for outdated versions of SilverStripe, even going back to 3.0.

I wonder if this module could automatically generate a sitemap.xml file that sets the priority of the stable channel to high, and unreleased and old versions to low? Hopefully that would signal to Google that they should surface e.g. api.silverstripe.org/en/3.6/class-File.html ahead of api.silverstripe.org/en/3.1/class-File.html.

Add an actual markdown editor in the docviewer to enable "wiki" mode.

Technical writers need less hoops to jump through to contribute larger edits to the docs.

Being able to allow certain users to be able to edit (would require some sort of authentication) the underlying markdown files.

Permisions for non-admins

I'm currently using the docsviewer for craeteing documention for content editors, however the docs can only be seen if the user has full admin rights. Is there a way to allow other user groups to view it?

Move common configuration to config api

To avoid the need of a custom theme for doc.ss.org which makes theming hard at the moment.

Use markdown metadata for generating title of the page.

We cant reliably convert filenames into proper english grammar, e.g. "Ingo's awesome changes" would be named "ingos-awesome-changes.md", which currently translates back into "Ingos Awesome Changes", losing the apostrophe and proper capitalization.

We might look into Markdown metadata for this purpose as well, in the form of:

Title: Ingo's awesome changes
Author: Ingo Schommer

Actual title of the page

body body body

Better search summary text

Currently it takes $Content, with all HTML stripped off. This means that the <h1> will be seamlessly connected to the first paragraph, which reads very werid, for example:

"Email Sending SilverStripe?'s test system has built-in support for testing emails sent using the Email class. How it works For this to work, you need to send emails using the Email class, which is g..."

"Forms Introduction Form is the base class of all forms in a sapphire application. Forms in your application can be created either by instantiating the Form class itself, or by subclassing it. Insta..."

Use SimpleXML to extract the first <p> tag, but careful with performance - ideally we cache this as a new property on indexing time rather than computing dynamically.

Documentation index should respect versions

Currently this displays everything for every version of documentation (if using the multiversions).

This ideally would return the index for the currently selected version of the documentation and display the select version interface.

Links to namespaced classes are broken

If I am not mistaken, then [api:SilverStripe\Framework\Injector\Factory] in https://github.com/silverstripe/silverstripe-framework/blob/3.1/docs/en/reference/injector.md will be turned into a link to the API docs.

the link should be:

http://api.silverstripe.org/3.1/class-SilverStripe.Framework.Injector.Factory.html

however, currently the generated link is:

http://api.silverstripe.org/3.1/class-SilverStripeFrameworkInjectorFactory.html

which is 404

API Links to class methods and properties are broken.

Examples: in the docs

(i) [api:DataObjectSet->populateDefaults()] is a 404. In the rendered page one sees that it is selecting the docs version being viewed (2.4,3.0,3.1, etc...) and the module. However, a closing ")" on the method is missing.

(ii) [api:DataObject::$defaults] goes to master when it should select the docs version being viewed.

Related ? /issues/37

Retain whitespace in markdown preformatted blocks

It removes lines considered "empty", see detail here: silverstripe/silverstripe-framework#837

default version number cannot be directly accessed

for example if my version 3.1 is default I can access this via site/en/ and not site/en/3.1/ - which makes permalinks to certain documentation for versions a pain point. Suggest both should be accessable with the default /en/ setting a canonical meta tag to the version perhaps?

Ability to config and drop the module name in the URLs

When using for a single set of docs it makes a longer and less rememberable URL - good feature would be to ignore and go direct to the markdown folder structure.

eg. http://localhost/framework/en/3.1/some-section/some-document/

simply becomes

http://localhost/en/3.1/some-section/some-document/

All [api] shortcode links are broken

Since we've moved to major version branches e.g. 4.x and 3.x, the version passed into the API website search URL is 4 or 3.

SS4 docs: The 4 branch doesn't exist yet, and could temporarily be changed to "master", although this could also be handled here in the API site code which might be prefereable.

SS3 docs: Currently the SS3 docs are passing 3 as the branch name, which isn't valid for the API site as it looks at minor versions. Otherwise, the version should be passed in as the stable minor version. The way the docs site is structuring it with major versions only, the stable minor is not available. This could also be handled temporarily with an htaccess redirect in api.silverstripe.org, or we could add another configuration parameter like ApiLinkBranch: 3.6 for example to docsviewer configuration.

Lastly, for namespaced API shortcode references, we need to convert to dot notation to match the API search format, e.g. \SilverStripe\ORM\DataExtension -> SilverStripe.ORM.DataExtension. This would be changed here.

---

Another alternative to the minor version branching mentioned above is that the API site could do a similar move as docs.ss (and soon userhelp.ss) and move to major version API docs only: 4.x and 3.x. Thoughts on this?

---

Related issues:

• #129
• silverstripe/api.silverstripe.org#32
• silverstripe/silverstripe-framework#5757
• silverstripe/api.silverstripe.org#33

Search broken on 3.1 with DocumentationViewer::set_link_base('');

Check out https://github.com/silverstripe/userhelp.silverstripe.org and activate the setting in app/_config.php to see this in action.

I think some routing changes in 3.1 mean that the first part of the URL (DocumentationSearchForm) is not treated as an action, so instead of search results you just get the plain homepage view.

"All" page should only list an item once for the stable version

Example:

Given that we are viewing /en/all and no version is implied by the URL, the docs viewer currently displays every topic title for every version. This results in many duplicated titles/versions.

In this instance should we assume the stable version, and use that to list the topic titles just once?

cc @tractorcow

Create "edit" buttons for doc.silverstripe.org

So, strictly speaking this will be a change for doc.silverstripe.org but I think that it would be best implemented as a module feature.

We have documentation, for example at:
http://doc.silverstripe.org/framework/en/trunk/misc/contributing.md

There is already an edit link for this page at:
https://github.com/silverstripe/sapphire/edit/3.0/docs/en/misc/contributing.md

I would like for us to have an "edit" button on our doc pages, pointing at this link. GitHub will take care of the rest.

SyntaxHighlighter requires a brush for bash

The page follows the Github Flavoured Markdown (GFM) convention for code blocks http://doc.silverstripe.org/framework/en/installation/windows-wamp

However our syntax highlighter in docsviewer doesn't have highlighting brush for this type.
Can we add one or switch highlighting js library that includes more markdown conventions including md extra and GFM

Prev/Next Links at Bottom missing dev/docs

The Prev/Next buttons at the bottom of the page return a link relative to site root:

http://mysite.com/en/documentation/sub_doc/sub_doc/
instead of
http://mysite.com/dev/docs/en/documentation/sub_doc/sub_doc/

All other links on the page are fine.

docsviewer search creating incorrect links?

The search on the docsviewer on doc.silverstripe.org is creating incorrect links, it is adding http://www.doc.silverstripe.org to all items in the search results

Code formatting for backticks around links

<backtick>[api:MyClass]<backtick> doesn't work, should format contents in <code>. Brought up in https://github.com/silverstripe/silverstripe-framework/pull/2412/files#r6368640

Manual ordering of pages and folders

Currently the main navigation has "Changelog" as the first element, because it happens to start with "C". Its also the least important element, much less so than "Tutorials". We need manual indexing, through Markdown metadata:

Title: Tutorials
Order: 1
To order a folder, the metadata would need to be placed in the contained index.md

(From http://open.silverstripe.org/ticket/6345)

Search on three char terms breaks with a server error

https://docs.silverstripe.org/en/results/?q=css&Versions=3.3&action_results=Search

Highlight search terms in search results summary

See http://ganeshhs.com/zend-framework/zend-search-lucene-part4-search-results-highlighting

Support for tripe backtick code blocks (for github+markdown syntax highlighting)

See silverstripe/silverstripe-environmentcheck#1 for background.

In the end, ::php doesn't get highlighted in github, but {backtick}{backtick}{backtick}php will.
A bit tricky to implement since the backtick notation requires "closing" backticks, and no tab indentation.
If we do that, it would be prudent to also convert existing code examples.

docsviewer doesn't appear to work with SS3.0.5

I installed a standard SS3.0.5 site and then add the DocsViewer module (master branch) to the /docsviewer folder at the document root and ran /dev/build.

When I try to access http://localhost/dev/docs, I get the errors below. We had docsviewer working in 2.4.x. What is the SS version requirement for the current version of docsviewer?

thanks,
Steve

[Warning] Missing argument 2 for DocumentationViewer::handleAction(), called in /Users/steve/__projects/quinn.com/etc/305_docroot/framework/control/RequestHandler.php on line 184 and defined
GET /dev/docs
Line 134 in /Users/steve/__projects/quinn.com/etc/305_docroot/docsviewer/code/controllers/DocumentationViewer.php
Source
125     /**
126      * Overloaded to avoid "action doesn't exist" errors - all URL parts in 
127      * this controller are virtual and handled through handleRequest(), not 
128      * controller methods.
129      *
130      * @param $request
131      * @param $action
132      * @return SS_HTTPResponse
133      */
134     public function handleAction($request, $action) {
135         try {
136             $response = parent::handleAction($request, $action);
137         } catch(SS_HTTPResponse_Exception $e) {
138             if(strpos($e->getMessage(), 'does not exist') !== FALSE) {
139                 return $this;
140             } else {
Trace
DocumentationViewer->handleAction(SS_HTTPRequest) 
RequestHandler.php:184
RequestHandler->handleRequest(SS_HTTPRequest,DataModel) 
Controller.php:153
Controller->handleRequest(SS_HTTPRequest,DataModel) 
DocumentationViewer.php:176
DocumentationViewer->handleRequest(SS_HTTPRequest,DataModel) 
Director.php:296
Director::handleRequest(SS_HTTPRequest,Session,DataModel) 
Director.php:119
Director::direct(/dev/docs,DataModel) 
main.php:126
[User Warning] None of these templates can be found in theme 'simple': DocFolderListing.ss
GET /dev/docs
Line 670 in /Users/steve/__projects/quinn.com/etc/305_docroot/framework/view/SSViewer.php
Source
661             $this->chosenTemplates = SS_TemplateLoader::instance()->findTemplates(
662                 $templateList, self::current_theme()
663             );
664         }
665 
666         if(!$this->chosenTemplates) {
667             $templateList = (is_array($templateList)) ? $templateList : array($templateList);
668 
669             user_error("None of these templates can be found in theme '"
670                 . self::current_theme() . "': ". implode(".ss, ", $templateList) . ".ss", E_USER_WARNING);
671         }
672     }
673     
674     /**
675      * Returns true if at least one of the listed templates exists.
676      *
Trace
None of these templates can be found in theme 'simple': DocFolderListing.ss 
SSViewer.php:670
SSViewer->__construct(DocFolderListing) 
ViewableData.php:325
ViewableData->renderWith(DocFolderListing) 
DocumentationViewer.php:652
DocumentationViewer->getContent() 
ViewableData.php:106
ViewableData->__get(Content) 
ViewableData.php:368
ViewableData->obj(Content,,,1,) 
ViewableData.php:408
ViewableData->cachedCall(Content,) 
ViewableData.php:421
ViewableData->hasValue(Content,,1) 
call_user_func_array(Array,Array) 
SSViewer.php:144
SSViewer_Scope->__call(hasValue,Array) 
SSViewer.php:490
SSViewer_DataPresenter->__call(hasValue,Array) 
SSViewer_DataPresenter->hasValue(Content,,1) 
.cache.framework.templates.Controller.ss:39
include(/private/var/folders/s2/r1m_qbxn1dn7fd0slybq9n_w0000gv/T/silverstripe-cache-Users-steve-__projects-quinn.com-etc-305_docroot/.cache.framework.templates.Controller.ss) 
SSViewer.php:838
SSViewer->includeGeneratedTemplate(/var/folders/s2/r1m_qbxn1dn7fd0slybq9n_w0000gv/T/silverstripe-cache-Users-steve-__projects-quinn.com-etc-305_docroot/.cache.framework.templates.Controller.ss,DocumentationViewer,,Array) 
SSViewer.php:910
SSViewer->process(DocumentationViewer) 
Controller.php:214
Controller->handleAction(SS_HTTPRequest,) 
DocumentationViewer.php:136
DocumentationViewer->handleAction(SS_HTTPRequest) 
RequestHandler.php:184
RequestHandler->handleRequest(SS_HTTPRequest,DataModel) 
Controller.php:153
Controller->handleRequest(SS_HTTPRequest,DataModel) 
DocumentationViewer.php:176
DocumentationViewer->handleRequest(SS_HTTPRequest,DataModel) 
Director.php:296
Director::handleRequest(SS_HTTPRequest,Session,DataModel) 
Director.php:119
Director::direct(/dev/docs,DataModel) 
main.php:126
[Warning] file_get_contents() [function.file-get-contents]: Filename cannot be empty
GET /dev/docs
Line 886 in /Users/steve/__projects/quinn.com/etc/305_docroot/framework/view/SSViewer.php
Source
877         if(isset($_GET['debug_profile'])) Profiler::mark("SSViewer::process", " for $template");
878         $cacheFile = TEMP_FOLDER . "/.cache" 
879             . str_replace(array('\\','/',':'), '.', Director::makeRelative(realpath($template)));
880 
881         $lastEdited = filemtime($template);
882 
883         if(!file_exists($cacheFile) || filemtime($cacheFile) < $lastEdited || isset($_GET['flush'])) {
884             if(isset($_GET['debug_profile'])) Profiler::mark("SSViewer::process - compile", " for $template");
885             
886             $content = file_get_contents($template);
887             $content = SSViewer::parseTemplateContent($content, $template);
888             
889             $fh = fopen($cacheFile,'w');
890             fwrite($fh, $content);
891             fclose($fh);
892 
Trace
file_get_contents() 
SSViewer.php:886
SSViewer->process(ViewableData_Customised,) 
ViewableData.php:335
ViewableData->renderWith(DocFolderListing) 
DocumentationViewer.php:652
DocumentationViewer->getContent() 
ViewableData.php:106
ViewableData->__get(Content) 
ViewableData.php:368
ViewableData->obj(Content,,,1,) 
ViewableData.php:408
ViewableData->cachedCall(Content,) 
ViewableData.php:421
ViewableData->hasValue(Content,,1) 
call_user_func_array(Array,Array) 
SSViewer.php:144
SSViewer_Scope->__call(hasValue,Array) 
SSViewer.php:490
SSViewer_DataPresenter->__call(hasValue,Array) 
SSViewer_DataPresenter->hasValue(Content,,1) 
.cache.framework.templates.Controller.ss:39
include(/private/var/folders/s2/r1m_qbxn1dn7fd0slybq9n_w0000gv/T/silverstripe-cache-Users-steve-__projects-quinn.com-etc-305_docroot/.cache.framework.templates.Controller.ss) 
SSViewer.php:838
SSViewer->includeGeneratedTemplate(/var/folders/s2/r1m_qbxn1dn7fd0slybq9n_w0000gv/T/silverstripe-cache-Users-steve-__projects-quinn.com-etc-305_docroot/.cache.framework.templates.Controller.ss,DocumentationViewer,,Array) 
SSViewer.php:910
SSViewer->process(DocumentationViewer) 
Controller.php:214
Controller->handleAction(SS_HTTPRequest,) 
DocumentationViewer.php:136
DocumentationViewer->handleAction(SS_HTTPRequest) 
RequestHandler.php:184
RequestHandler->handleRequest(SS_HTTPRequest,DataModel) 
Controller.php:153
Controller->handleRequest(SS_HTTPRequest,DataModel) 
DocumentationViewer.php:176
DocumentationViewer->handleRequest(SS_HTTPRequest,DataModel) 
Director.php:296
Director::handleRequest(SS_HTTPRequest,Session,DataModel) 
Director.php:119
Director::direct(/dev/docs,DataModel) 
main.php:126

Problem on WAMP with Directory separator

Children menu in sidebar is not displaying due to DIRECTORY_SEPARATOR in function getChildrenFor in DocumentManifest.php (line 621)

        // only pull it up if it's one more level depth
        if(substr_count($pagePath,DIRECTORY_SEPARATOR ) == ($depth + 1)) {

should be

        // only pull it up if it's one more level depth
        if(substr_count($pagePath, '/') == ($depth + 1)) {

Add "last changed" status for each page

Knowing how "up to date" a piece of docs is can be important for the reader - e.g. you wouldn't trust a DataObject? API that was last updated in 2007.

This relies on the page inspecting the svn/git status of a module checkout, and looking at the properties for a specific file. Please ensure this does not harm rendering performance too much - if it does, we need to cache this information.

Composer update fails

Composer update now fails due to some branch changes in an external module. There error I'm getting is:

    - silverstripe/docsviewer dev-master requires erusev/parsedown dev-fixgreaterthan as ~1.0 -> no matching package found.
    - silverstripe/docsviewer dev-master requires erusev/parsedown dev-fixgreaterthan as ~1.0 -> no matching package found.
    - Installation request for silverstripe/docsviewer dev-master -> satisfiable by silverstripe/docsviewer[dev-master].

It looks like the fixgreaterthan branch has been removed from the module, but I don't know enough about this module to suggest a fix other than a guess that dev-master is probably ok now?