Projects

Table of contents

1. Creating Projects
2. Configuring Projects
3. JMap extensions compatible with JMap NG
4. Managing Projects
5. Project Permissions
6. Multilingual Projects
7. Organizing Layers
8. Attribute Queries
9. Style Templates
10. Personal Layers

---

In JMap, map data is organized in projects. A project is composed of an ordered list of layers. Typically, when a JMap application connects to JMap Server, the application opens a project and displays the project layers. You can create as many projects as you want.

Each layer of a project is associated with a spatial data source. The data source provides the data of the layer. Different projects can contain layers sharing the same data sources, allowing different data bindings, styles, etc. for the same data. Also, more than one layer in a project can share the same data source. This is useful when using layer filters to show different data of the same data source on multiple layers.

A project is a secured resource, which means that permissions are associated with it in order to control access by users. This allows precise control of which users or groups will be allowed to open each project. Similar access control is also available for each layer in the project.

Creating Projects

To create a new project, press Create in the section listing the projects. Projects are created by walking through a wizard.

Project source

When creating a project, you can either create a new empty project or import an existing project configuration from another source. When you use an existing configuration, you can automate the creation of the project’s layers and avoid reconfiguring everything in JMap Admin. Currently, only one option is available for importing a project configuration: importing projects from an ESRI ArcGIS REST Service.

Importing ArcGIS REST projects

You can choose to import the layer configuration from an ESRI ArcGIS REST service. JMap will import the project’s parameters, the layers and their symbology, the scale parameters, the extents, etc.

Select the ArcGIS REST option and click on Next.

JMap supports the import of OGC WMTS raster layers.

In the REST service layer import interface, icons indicate layers whose format is not compatible with JMap.

Vector tiles in JMap

Vector tiles are a format of vector data that is very effective for web-based mapping. With vector tiles, the entire vector data of a project is divided into tiles, similarly to raster data tiles (WMTS).

There are several standards for creating vector tiles. Mapbox has provided a standard based on the protocol buffer encoding (“Protobuf”) created by Google (https://developers.google.com/protocol-buffers). Mapbox vector tiles (mvt) are supported by a wide range of map-based products, including JMap 7 as of the Jakarta version.

A grid defining the tiling is applied to the vector data, which is split into tiles. Each tile can contain the vector data (vectors) of several layers.

A set of tiles is produced for each scale level. Generally, there are 23 scale levels in web-based mapping, 0 being Earth level and 22 being street level. The vectors of lower levels are simplified (generalized) to optimize the display of the data, while maintaining a volume of tiles that performs well.

The vectors (lines, polygons) of each layer are clipped at the boundaries of the tiles. When a geometry crosses over the boundary between tiles, it is cut, and each tile thus contains part of the geometry. The map application reunites the vectors to obtain the full geometry.

The attributes of map elements are included in the tiles. This makes it possible to display thematics created on the fly or to display data in a map using attribute filters, for instance. This makes the data more dynamic and interactive.

The vector tiles contain the geometries and their attributes; styles are not included in the tiles. The information defining the styles is stored and managed in a separate JSON file. This feature allows application users to define styles dynamically, since the applications manage the styles. In addition, when the style of the data changes, it is not necessary to generate new tiles.

Tiles can be created in advance and cached; the server responds much more quickly to queries from the web-based mapping application, and therefore the rendering of the map is very smooth and performs well. In addition, the tiles can be used with WebGL for smooth and efficient rendering, especially in 3D.

Producing vector tiles with JMap

A JMap project generates three sets of data that are used by the applications:

• 1 JSON style file. This file accompanies the vector tiles. It contains the definition of each layer contained in the vector tiles, their style parameters, the thematics, etc.

• A set of vector tiles containing the geometries and attributes of non-editable layers. JMap produces an MVT file for each tile. These tiles can be created on request when users navigate through the JMap Survey or JMap NG applications. They can also be created in advance and cached. The following article offers details on how to create and manage the cache of tiles with JMap.

• GeoJSON vector data corresponding to the geometries and attributes of editable layers. This data is sent to applications on request, by region.

Regardless of the procedure used to create tiles (on request or in advance with caching), the tiles are created in the cache/mapbox directory of JMap Server. In this directory, there is one folder per project (named using the project ID), which contains one folder per resolution (currently 512). The files of the tiles are named using the z-x-y.mvt code, where z is the scale level, and x and y indicate the position of the tile in the grid.

Factors affecting the performance of vector tiles

In general, vector tiles are lighter than raster tiles, but some factors can affect the size of tiles and impact the performance of the JMap Survey and JMap NG applications. The size of tiles is associated with the time it takes to produce them, their storage volume, the volume of data exchanged with the applications, and the dedicated memory of the applications.

Some factors to consider:

• Number of attributes bound to layers: the attribute data influences the size of the tiles; the more attributes there are, the more the size increases.

• Layer visibility scales: Establishing visibility thresholds for the display of layers is recommended when layers have very dense data. A good strategy is to limit the display of these layers to larger scales because the tiles of the smaller scales will not contain the data of these layers, and the time required to produce the tiles will be reduced.

• Caching: producing tiles in advance and caching them greatly improves application performance, while reducing JMap Server’s workload. JMap Server can indeed reach its full workload capacity when several users are navigating through large and complex projects in the applications.

• JMap server memory: influences the performance of tile production. Increasing the memory allocated to the JMap server can accelerate tile production.

Configuring Projects

The configuration interface of a project allows you to access information on the project. This interface also contains functions to configure various parameters, such as the initial view of the project in the applications.

JMap Web Preview

The JMap Web Preview opens a JMap Web application in a new browser window.

The preview offers all the functionality of JMap Web applications and allows you to validate the project’s configuration. It also allows you to configure the initial view of the project when it is opened in JMap Web applications. To do this, click on and then on Initial extent. A rectangle displays to delimit the initial extent. Click on Maximum extent to display the maximum extent. When you close the preview, the geographic coordinates of the initial extent are automatically saved.

JMap NG Preview

The JMap NG preview opens a JMap NG application in a new browser window.

The preview offers all the features of JMap NG applications and allows you to validate the project configuration.

JMap Pro Preview

The JMap Pro Preview opens a JMap Pro application offering all the functionality of JMap Pro applications. You can validate the project configuration.

You can also delimit the initial view of the project, when it is opened in JMap Pro applications. Click on . A rectangle displays to delimit the initial view. When you close the preview, the geographic coordinates of the initial view are automatically saved.

Image producer

The image producer of a JMap project is used to produce images on demand for that project. These images are used for JMap Web applications. When a user works in JMap Pro, the image producer is not used because the data is transferred in vector format (except for photos).

Normally, the image producer’s settings do not need to be modified because the default configuration is adequate. The following table describes the settings of the image producer.

JMap extensions compatible with JMap NG

Extensions which are compatible with JMap NG applications (which are not deployed, see chapter JMap Applications for details), are automatically displayed in projects. You can therefore configure them at this level and make them accessible to users of the JMap NG application which publish the project.

The chapter JMap Extensions provides details on the configuration of extensions in JMap Server.

To configure the extension at the project level, click on the extension name in the menu. Once the configuration is complete, press Save.

Managing Projects

The Projects section in JMap Admin displays a list of existing projects. From this section, projects can be created, cloned or deleted.

Modifying an existing project

A project can be modified by pressing Edit from the project detail section. Modifying a project goes through the same steps as when the project was created. If the projection of the project is changed, the vector data cache of the layers is cleared.

Cloning projects

You can clone an existing project by selecting it from the table and pressing Clone. All layers inside the project are copied to the new project. Note that the underlying spatial data sources and databases are not copied. Instead, they are shared between the layers of the new project and the layers of the old project.

Deleting projects

You can delete an existing project by selecting it in the table and clicking on Delete. You can also delete a project from its configuration section. Deleting a project permanently deletes all layer configurations included in it. The spatial data sources are not affected.

Project Permissions

From the project detail section, press Permissions to access the project permissions section. A list of currently allowed users and groups is displayed. Press to add new users or groups and automatically grant them the Open this project permission. The available users and groups are configured in the JMap Server section in JMap Admin. See Managing User Accounts and Groups for more information about managing users in JMap.

Project permissions are divided into two categories: administrator permissions and user permissions.

Administrator permissions

Administrator project permissions define the project administration rights for the users authorized to use JMap Admin. For more information on concepts related to permissions and administration roles in JMap Admin, refer to the Managing Permissions section.

User permissions

User project permissions determine which users and groups can open a project. Access will be denied to users who do not have the appropriate permissions. Security can also be configured at the layer level. For more information on this topic, refer to the Layer Permissions section.

Anonymous user

Adding the anonymous user to the list of users authorized to open the project gives users the possibility to open a project without any authentication. This is equivalent to removing all security for opening the project. This is useful for public applications, when no project access control is needed.

Everyone user

Adding the everyone user to the list of users authorized to open the project allows any authenticated user to open a project. This is useful for private applications where all users are allowed to open a project but must authenticate themselves.

Multilingual Projects

JMap projects can be configured to support several languages. This way, each user can view the project in his or her own language, as long as the language is available and the translations have been provided. When a JMap application is launched, it can automatically identify the language of the user’s operating system and use this language for the project and graphical interfaces. This behavior depends on the options selected when deploying the application.

For a project supporting multiple languages, each text element that is visible to the users can be translated into each language. For example, you can provide translations for the project name, the names of the layers, labels, mouseover bubbles, forms, etc.

To enable multilingual support, you must choose at least 2 languages when creating or editing a project. You must also select the default language.

Afterwards, you can enter the translations in the sections identified with the symbol when configuring the project and layers. The figure presents the translation interface for a project supporting 3 languages.

If translations are not provided in all available languages for certain text elements, the text will automatically be displayed in the default language.

Organizing Layers

There are two aspects to organizing layers in a project. One is to define the order of appearance of the layers on the map. Layers at lower positions are drawn first and layers at higher positions are drawn at the end. Top layers can hide elements of bottom layers. The other aspect is to create a logical hierarchy based on the nature of the layers. In other words, this allows the creation of groups (and subgroups) of layers that have a logical relationship. For example, there could be a group of layers related to roads, another to hydrography, and another to census. Organizing them in groups makes it easier for the users to work with layers.

To start organizing the layers, open the Layers section of the project.

Ordering layers

To order layers of a project, open the tab titled List. This section presents the layers in their order of appearance on the map. The lowest position is the first layer to be drawn on the map. To change the order, you must use the Modify menu located at the top of the column displaying the position of each layer. You can also select one or more layers and move them using the available options (Move up, Move down, Move at…, etc.). In addition, you can open a window displaying all the layers and reorder them using drag-and-drop actions.

Grouping layers

To organize layers in groups, open the tab named Hierarchy. This section presents the current hierarchy of layers. By default, all layers of the project are in one unique group called Layers. To create a new group, press Create group. Fill the layer group parameters as described below:

Once groups have been created, you can move layers towards these groups using the Modify menu located at the top of the column displaying the position of each layer.

Attribute Queries

Attribute queries are used to find and select elements of a map layer using their attribute values or a database associated with the layer. In JMap Admin, JMap administrators create the queries and their associated forms. Then, users of JMap applications use those forms to enter attribute values to search for. All elements whose attribute values match the values entered are then selected or listed in an elements explorer.

You can access the query configuration section by clicking on Queries in the Projects section.

Creating a new attribute query

To create a new query, press the Create query button in the Attribute queries section. This will open the query configuration interface. Parameters will vary depending on the type of query selected.

Layer queries

| Layer queries | | | —————– | ———————————————————— | | WHERE | WHERE clause of the SQL query used to run the search. Here is where all the search criteria will be defined. Typically, this clause contains numbered parameters ($param1, $param2, etc.) that will be replaced by the values the user enters in the form.

Examples:

COUNTRY='$param1'

Selects the layer elements for which the attribute value COUNTRY is equal to the value entered by the user. The attribute value must perfectly match the value entered ($param1).

lower(COUNTRY) like lower('$param1%')

Selects the layer elements for which the attribute value COUNTRY is similar to the value entered by the user. The attribute value must begin with the value entered ($param1). Since the lower operator is used, the search is not case sensitive.

POP2000>=$param1 and POP2000<$param2

Selects layer elements that have the POP2000 attribute value within the range defined by the two values that were entered ($param1 and $param2). | | Form layout | Press this button to configure the query form. See Forms for more information. |

External queries

This type of query is used when the search must be conducted within the data of an external database. The external database must contain a field that links to a layer attribute. A select SQL query is executed in the external database and the values returned are then associated with the layer elements using the link field.

Required and optional parameters

Although search forms are designed to mark fields as required or optional, the where clause of the query must be adjusted to support this option. To accomplish this, any part of the query that is associated with optional parameters must be included between braces ( { } ).

Example of WHERE clause:

CITY = '$param1' and { COUNTRY = '$param2' }

This example searches for cities for which the attribute value CITY is equal to the value of parameter 1 ($param1) entered by the user and who optionally have their value for the COUNTRY attribute equal to the value of parameter 2 ($param2) entered by the user. If parameter 2 is left blank , the entire block { COUNTRY = '$param2' } is removed from the query, along with the and operator, which is now an orphan. Note that the administrator must absolutely define $param2 as optional when designing the form. Refer to the Forms section for more information on designing forms.

Multiple values for the same parameter

Multiple values can be entered with a List (multiple choices) type field in the forms. The values are separated by the delimiter character ; (semicolon). This option can be activated in the WHERE clause of the query. The syntax is as follows:

$multiple{true|false} {$delimiter{;}}

Example:

CITY = '$param1{$multiple{true} $delimiter{;}}'

Searches for cities whose CITY attribute value is equal to one of the values entered in parameter 1. The values are separated by semicolons.

Managing attribute queries

Attribute queries can be modified by administrators. In JMap Dakar and later versions, when a project’s queries are modified, the applications that disseminate the project do not need to be redeployed because the changes are reflected directly.

Organizing attribute queries

Attribute queries can be organized into groups.This is particularly useful for projects that have a large number of queries.

To create a new group, click on the Create group button. To modify the order of groups, click on the Modify button and select Reorder groups. The window that is displayed allows you to drag and drop the groups in order to change their order. To rename a group, click on . To delete a group, select it in the list and click on Delete.

Deleting attribute queries

Deleting an attribute query permanently deletes the query and its associated form. To delete a query, select it in the list and click on Delete.

Publishing queries

Once a query has been created, it is automatically published. However, you can disable this publication, which will make your query unavailable in applications, but its configuration will still be saved. If you do not want your query to be published, clear the Published checkbox of your query in the query management interface.

Queries on referenced layers

When a project contains referenced layers, the queries configured on these layers are automatically available in the project. The project “inherits” these queries.

You cannot modify these queries from the project; they can only be modified in the project that contains the original layer.

If you wish to make changes to a query on a referenced layer, create a copy of the query by clicking on Clone. The configuration interface shows the search parameters that you can modify.

Once the new query has been configured, you can clear the Published check box of the query that was “inherited” from the referenced layer if you no longer want it to be available in JMap applications. If the Published check box is cleared for an attribute query on a layer, that query will no longer be available in the projects that use the referenced layer.

You can also create a new query on a referenced layer as described in the section Creating a new attribute query.

Style Templates

Style templates are predefined styles that can be reused across many projects and layers. They help save time because a style can be configured once but used at many places. Style templates also help create standardized maps.

Once a style template is configured, it can be used in every place a style is needed (layer styles, selection styles, thematics, etc.). A style template can be used as a reference or as a copy. When used as a reference, if the style template is modified, all layers that refer to it will also use the modified style. When used as a copy, the style is detached from the style template and can be modified independently thereafter.

Style templates are associated with only one type of map element (point, line, polygon, etc.) and cannot be used for other types of elements.

To use a style template, click on Use a style template from any style configuration interface. See Style for more information.

You can access the style template configuration section by clicking on Style templates in the Projects section.

Creating style templates

To create a new style template, press Create.

The rest of the configuration depends on the selected element type and is identical to normal style configuration. See Style for more information. Press Finish to complete the creation of the style template.

Deleting style templates

To delete a style template, select it in the list and press Delete.

Personal Layers

Personal layers are layers of data created and populated by users. When creating a new personal layer, the user specifies a name, a geometry type and a set of attributes. The layer configuration and the data (geometries and attributes) are stored in the JMap Server System database. Once they have been created, personal layers can be shared between users with a permission system. They can also be converted to normal layers inserted in a project by the administrator. Users need a special permission granted by the administrator to create personal layers.

You can access the personal layers section by clicking on Personal layers from the Projects section.

In JMap Admin, the administrator can see a list of existing personal layers. It can be displayed by personal layer or by user. When selecting a personal layer, you can see which users have access to it. When selecting a user, you can see which personal layers the user has access to. You can also click on a personal layer in the list to open its details section.

Deleting a personal layer

To delete a personal layer, select it in the list and press Delete. Be aware that deleting a personal layer also deletes its configuration and all its data. This action cannot be undone.

Publishing a personal layer

Publishing a personal layer transforms it into a regular project layer. Once it is published, a personal layer can no longer be managed by users. However, it can still be edited if the administrator grants the appropriate permissions to users. To publish a personal layer, select it in the list, press Publish and select the project in which the layer will be inserted.

---