Relative vs absolute link edits

CHANGELOG.md

@@ -20,6 +20,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 - Clarified the role of geometries on items in the label extension
 - Data Cube Extension: Units for STAC dimensions in should now be compliant to UDUNITS-2 units (singular) whenever available.
+- URIs (usually found int properties like `href`, `url`) are now validated using the `iri-reference` format in JSON Schema (allows international characters in URIs)
 - Relaxed the regular expression for DOIs in the scientific extension ([#910](https://github.com/radiantearth/stac-spec/issues/910))
 
 ### Removed

best-practices.md

@@ -254,10 +254,10 @@ STAC version. Otherwise some behaviour of functionality may be unpredictable (e.
 
 ## Use of links
 
-The main catalog specification allows both relative and absolute links, and says that `self` links are not required, but are 
+The STAC specifications allow both relative and absolute links, and says that `self` links are not required, but are 
 strongly recommended. This is what the spec must say to enable the various use cases, but there is more subtlety for when it 
-is essential to use different link types. The best practice is to use one of the below 
-catalog types, applying the link recommendations consistently, instead of just haphazardly applying anything the spec allows.
+is essential to use different link types. The best practice is to use one of the below catalog types, applying the link 
+recommendations consistently, instead of just haphazardly applying relative links in some places and absolute ones in other places.
 
 ### Self-contained Catalogs
 

catalog-spec/catalog-spec.md

@@ -58,9 +58,8 @@ with links.
 
 A more complete list of possible 'rel' types can be seen at the [IANA page of Link Relation Types](https://www.iana.org/assignments/link-relations/link-relations.xhtml).
 
-Please see the chapter 'relative vs absolute links' in the [Item spec](../item-spec/item-spec.md#relative-vs-absolute-links)
-for a discussion on that topic, as well as the [use of links](../best-practices.md#use-of-links) section of the 
-catalog best practices document.
+For a full discussion of the situations where relative and absolute links are recommended see the
+['Use of links'](../best-practices.md#use-of-links) section of the STAC best practices.
 
 #### Relation types
 

catalog-spec/json-schema/catalog.json

@@ -33,7 +33,7 @@
               {
                 "title": "Reference to a JSON Schema",
                 "type": "string",
-                "format": "uri"
+                "format": "iri"
               },
               {
                 "title": "Reference to a core extension",
@@ -72,7 +72,8 @@
       "properties": {
         "href": {
           "title": "Link reference",
-          "type": "string"
+          "type": "string",
+          "format": "iri-reference"
         },
         "rel": {
           "title": "Link relation type",

collection-spec/collection-spec.md

@@ -118,7 +118,10 @@ This object describes a relationship with another entity. Data providers are adv
 | type       | string | [Media type](../item-spec/item-spec.md#media-types) of the referenced entity. |
 | title      | string | A human readable title to be used in rendered displays of the link. |
 
-Please see the chapter 'relative vs absolute links' in the [Item spec](../item-spec/item-spec.md#relative-vs-absolute-links) for a discussion on that topic.
+A more complete list of possible 'rel' types can be seen at the [IANA page of Link Relation Types](https://www.iana.org/assignments/link-relations/link-relations.xhtml).
+
+For a full discussion of the situations where relative and absolute links are recommended see the
+['Use of links'](../best-practices.md#use-of-links) section of the STAC best practices.
 
 #### Relation types
 

collection-spec/json-schema/collection.json

@@ -30,7 +30,7 @@
               {
                 "title": "Reference to a JSON Schema",
                 "type": "string",
-                "format": "uri"
+                "format": "iri"
               },
               {
                 "title": "Reference to a core extension",
@@ -83,7 +83,7 @@
               "url": {
                 "title": "Organization homepage",
                 "type": "string",
-                "format": "url"
+                "format": "iri"
               }
             }
           }

item-spec/item-spec.md

@@ -114,13 +114,8 @@ It is allowed to add additional fields such as a `title` and `type`.
 | type       | string | [Media type](#media-types) of the referenced entity. |
 | title      | string | A human readable title to be used in rendered displays of the link. |
 
-#### Relative vs Absolute links
-
-Currently, the JSON schema for links does not require them to be formatted as URIs, to allow
-implementors to provide relative links. In general, Catalog APIs should aim to provide absolute links
-whenever possible. Static Catalogs are potentially more portable if they incorporate only
-relative links, so that every link doesn't need to be rewritten when the data is copied. Additional
-recommendations for particular `rel` types are given in the `rel` type description.
+For a full discussion of the situations where relative and absolute links are recommended see the
+['Use of links'](../best-practices.md#use-of-links) section of the STAC best practices.
 
 #### Relation types
 

item-spec/json-schema/item.json

@@ -104,7 +104,7 @@
                   {
                     "title": "Reference to a JSON Schema",
                     "type": "string",
-                    "format": "uri"
+                    "format": "iri"
                   },
                   {
                     "title": "Reference to a core extension",
@@ -150,7 +150,8 @@
       "properties": {
         "href": {
           "title": "Link reference",
-          "type": "string"
+          "type": "string",
+          "format": "iri-reference"
         },
         "rel": {
           "title": "Link relation type",
@@ -188,7 +189,8 @@
       "properties": {
         "href": {
           "title": "Asset reference",
-          "type": "string"
+          "type": "string",
+          "format": "iri-reference"
         },
         "title": {
           "title": "Asset title",

item-spec/json-schema/provider.json

@@ -37,7 +37,7 @@
           "url": {
             "title": "Organization homepage",
             "type": "string",
-            "format": "url"
+            "format": "iri"
           }
         }
       }