AllegroGraph Web View ― user manual

The AllegroGraph Web View is an interface for exploring, querying, and managing AllegroGraph triple stores through a web browser.

Installation

Simply download the appropriate file from http://agraph.franz.com/agwebview, and unpack it somewhere.

Running Web View

To use Web View, a server program has to be started, either on your own computer or on a server somewhere. This server is then accessed through a web browser. The agwebview (.exe on windows) file is used to start such a web-server.

Most of the configuration can be done through the browser, but some options have to be provided when starting the server. These are passed as command-line options to agwebview.

--port number

The port on which to run the HTTP server. Defaults to 8080.

--account name:password

Causes the server to create an administrative account using the given name and password. You'll have to pass this the first time you start the server, or you won't have an account to configure it.

--publish name:directory[:read-only]

Publishes the triple store in the given directory under the given name. When ":read-only" is prepended the store can not be modified through the Web View interface. This option can be passed multiple times. Stores can also be published through the web interface.

--cache directory

Determines where persistent settings and user accounts should be saved. Defaults to 'site-cache' in the installation directory.

--log file name

Specifies where logging output should be written.

--debug

Run the server in debug mode.

--no-local-stores

Disable opening of local stores on this server.

--no-remote-stores

Disable opening of remote stores.

--no-new-stores

Do not allow users to create new triple stores.

One could run, for example, this:

agwebview --port 5000 --account me:xyzzy

Now, going to http://localhost:5000 presents you with the front-page of the Web View. There is not much to be seen here yet, since we haven't opened any stores. To start configuring the site, click 'login' in the bar at the top of the screen, and use the administrative account we created: user name 'me', password 'xyzzy'.

After logging in, a lot more controls are visible. Stores can be added to the site, and settings can be modified. Note that all the configuration options and user accounts are stored on disk, in the site-cache directory in the installation directory, and will be remembered when the server is restarted. Use the --cache command-line option to run a server that saves its configuration in a different place.

If you have an AllegroGraph store somewhere on your system, try opening it. Enter its path in the 'File' field of the 'Open a local store' form, and give it a name. If you have no store, create an empty one instead. After clicking 'Create', a link to the store should appear on the top of the page.

User interface

When opening a store in Web View, you start at the store's overview page. This lists some information about the store, and, when logged in with an administrator account, provides the interface for managing the store and the Web View settings for that store.

A store overview

A store has a description, a set of 'notable' nodes (good starting points for users), a set of pre-defined queries, and some default namespaces. These can be used to make it easier for others to get familiar with the store, but are not much use if you are just using Web View to explore a store yourself.

Throughout the interface, a SPARQL-style notation is used for RDF resources and literals. <http://example.com> is used for URLs, which an be abbreviated to something like rdf:type (note the absence of < and >) if a suitable namespace has been defined. Literals are "quoted", optionally with a type or language postfixed like "10"^^xsd:integer or "ten"@en. When the 'long parts' toggle (visible in the navigation bar) is enabled, resources are always displayed in full. When it is disabled, a shortened form is displayed (mousing over them gives a tooltip with the full form). Resources always link to their 'context' page, which shows a list of triples that the resource is involved in.

Node context view

At any time, a set of namespaces is active, which are used to shorten URLs. When not logged in, only the default namespaces are active. Logged-in users can configure the set of namespaces they want to use by clicking the 'namespaces' link in the top bar.

Queries can be executed by clicking 'Queries: new' in the top bar. This brings up an empty input area where a SPARQL query can be entered. When Prolog queries are enabled for the site, there is a menu that can be used to set the query language to Prolog instead. An overview of recently executed queries is available under 'Queries: recent'.

Executing a Prolog query

At any time, a query can be given a name and saved. This causes the query to appear in the 'Queries: saved' list, and to get a fixed URL. If the 'shared' check-box was checked when saving the query, this URL can also be accessed by others. Administrative users can add their saved queries to the store (from the 'Queries: saved' list), to make them appear in the store overview.

Graph names are not displayed by default, but when they are toggled on (see the check-box in the top bar), views that show triples (node context and text search results) will also show the named graph that each triple belongs to.

The search box in the top right of the screen (only visible if the triple store uses free-text indexing) will search the predicates that are indexed, displaying a list of matching triples. Note that it does not search all literals.

When a Google key is set for the site, data using AllegroGraph's geospatial format can be mapped with Google Maps:

Mapping query results

Visualizing the results of a CONSTRUCT query