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GratisGIS documentation. Pick a topic from the sidebar or use the search box to find what you need. Each page covers one concept end-to-end, no five-step workflows in your way when you just want to know how Buffer works.

Getting Started

  • What is GratisGISGratisGIS is a self-hosted open-source portal for publishing maps, datasets, forms, and apps. Same shape as ArcGIS Online, no commercial licensing.
  • Creating your first mapStart a new map item, add a layer, save. The single shortest path from "I just signed in" to "I have a map I can share."
  • Sharing an itemEvery item carries its own ACL. This page shows you the three sharing tiers and how to change them.

Coming From Arcgis

  • Coming from ArcGIS OnlineOrientation pages for ArcGIS Online and ArcGIS Pro users moving to GratisGIS. Same workflows, different names.
  • Terminology mapWord-for-word mapping between ArcGIS Online vocabulary and GratisGIS vocabulary.
  • Feature service to data layerMove an ArcGIS Online hosted feature service into a GratisGIS data layer. Schema, symbology, and features all come over.
  • Web map to mapImport an ArcGIS Online web map JSON into a GratisGIS map. Layers, basemap, viewport, and styling come over.
  • Survey123 to formBring a Survey123 survey over by exporting its XLSForm and importing into a GratisGIS form item.
  • App builders comparisonHow Esri's Experience Builder, Web AppBuilder, and Dashboard Designer concepts map onto the GratisGIS Web app and Dashboard items.

Items

  • MapAn item that composes layers, a viewport, and a basemap. Maps are what web apps render and what print templates print against.
  • Data layerAn item that holds one or more PostGIS-backed feature tables. The native equivalent of an Esri feature service.
  • Bundle exportPack a data layer (and optionally its related tables and feature attachments) into a single ZIP archive.
  • FormAn item that collects new features or non-spatial responses from people in the field or at their desks. The native equivalent of a Survey123 survey.
  • Form submission collectionA non-spatial item type that stores form responses when those responses don't map onto a feature.
  • Web appA standalone web page built from a map plus widgets. The native equivalent of an Experience Builder or Web AppBuilder app.
  • DashboardA grid of indicators, charts, and small maps that summarize a set of layers in one screen.
  • Report templateA parametrized document layout that produces a PDF (or DOCX) populated from layer data on demand.
  • FileAn item that wraps an arbitrary uploaded file. Use for reference documents, archived deliverables, or anything that doesn't fit a more specific item type.
  • Pick listA reusable list of coded values with labels, referenced by fields on data layers and forms.

Map Editing

  • LabelsRender a text label per feature, computed from one or more fields, with placement and visibility controls.
  • FiltersShow only the features of a layer that match a condition, without altering the underlying data.
  • PopupsCustomize what shows when a user clicks a feature: title, body, field list, attachments, links.
  • ViewportThe default center, zoom, bearing, and pitch a map opens at, plus optional bookmarks for saved views.
  • Simple symbologyRender every feature of a layer with the same fill, stroke, and size. The default and the right starting point.
  • Categorical symbologyRender each feature differently based on the value of one field. Status colors, asset types, land use classes.
  • Graduated symbologyDrive a feature's color (or size) by a numeric field, using class breaks or a continuous ramp.
  • Scale classesRender one layer with different colors at different zoom levels without forking it into two layers.

Forms

  • Form designerThe visual builder for a form item. Drag in questions, set validation, preview, publish.
  • Question typesThe catalog of form question types and which backing field types they're compatible with.
  • Conditional logicShow or hide form questions based on the answers to earlier questions. Same expression dialect as filters and calculate steps.
  • Importing an XLSFormBring a Survey123, ODK, or KoboToolbox XLSForm into a GratisGIS form item. The form designer's Import button accepts .xlsx alongside .json.

Web Apps

  • Custom Web AppThe drag-and-drop builder for the Custom web app template. Layout, widgets, theme, and configuration on one canvas.
  • TemplatesThe four built-in web app templates and which is the right fit for each use case.
  • ThemesPer-web-app color, font, and logo overrides. Picks up the org brand by default; lets one app stand out.
  • Layer list widgetA panel that lists the map's layers with toggle-on / toggle-off, opacity, and per-layer actions.
  • Search widgetA search bar that finds locations (via a geocoder) and / or features (via field-text search).
  • Export widgetToolbar tool that downloads the visible features of the bound map as CSV or Excel.
  • Print widgetGenerate a printable PDF (or PNG / JPEG) of the current map view, with title, legend, north arrow, scale bar.
  • Attribute table widgetA bottom panel that shows feature rows in a sortable, filterable table tied to one or more map layers.
  • Basemap gallery widgetLet viewers switch the map's basemap from a curated list. Streets, imagery, topographic, your custom basemap.
  • Splash widgetA modal dialog that opens when a Custom Web App loads. Use for welcome messages, disclaimers, or required terms of use.

Print Templates

  • Print template overviewHow report templates produce paper-shaped documents from layer data, and when to pick a template over the Print widget.
  • ParametersThe inputs a runner supplies when generating a report. Types, defaults, validation.
  • Template tokensThe placeholder syntax authors put in the body to bind layer data into the rendered document.

Analysis

  • FilterKeep rows from a source layer that match an expression. The simplest derived-layer step.
  • CalculateAdd a computed column to a layer. The same input rows, plus one or more new derived attributes.
  • Spatial joinAttach attributes from one layer to features of another, based on a spatial relationship (intersects, within, contains, nearest).
  • BufferExpand each input feature outward (or inward) by a fixed distance to produce a polygon at that offset.
  • Group byRoll up rows by one or more keys, producing aggregates (count, sum, average, min, max) per group.
  • DissolveMerge adjacent polygons that share an attribute value into one multipolygon per shared value.
  • CentroidReplace each feature's geometry with a single point at its center.
  • ClipKeep only the parts of input features that fall inside a clip polygon. Cookie-cutter style.
  • FishnetGenerate a regular grid of square (or hex) polygons over an extent. The starting layer for any "binned-by-cell" analysis.
  • ContourGenerate iso-lines (or iso-polygons) from a value column on a point or cell layer.

Admin

  • HousekeepingThe admin dashboard that surfaces stale items, quiet users, and orphaned dependencies, with bulk actions to clean up.
  • GeocodersConfigure address-to-location services used by the search bar, the form designer's location-pick widget, and reverse geocoding in popups.
  • BackupsHow GratisGIS backups work, where they live, how to restore, and what they don't cover.
  • Organization settingsOrg-wide preferences: default basemap, default item sharing, storage budget, allowed file types, contact info.
  • RolesHow user roles work, who can do what, and how to assign or change a user's role.
  • BrandingCustomize the portal's logo, colors, fonts, and footer text. Org-wide presentation.

Reference

  • Item typesThe full catalog of GratisGIS item types in one place, with one-line descriptions and links to each item's detail page.
  • Expression languageThe SQL-like dialect used across filters, calculate steps, conditional visibility, and template tokens. One vocabulary, many surfaces.
  • GlossaryQuick lookup of GratisGIS-specific terms. Each entry one or two sentences.