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Internet Engineering Task Force (IETF)                        S. GilliesRequest for Comments: 8142                                        MapboxCategory: Standards Track                                     April 2017ISSN: 2070-1721GeoJSON Text SequencesAbstract   This document describes the GeoJSON text sequence format and   "application/geo+json-seq" media type.  This format is based on   JavaScript Object Notation (JSON) text sequences and GeoJSON, and it   makes arbitrarily large geographic datasets incrementally parseable   without restricting the form of GeoJSON texts within a sequence.Status of This Memo   This is an Internet Standards Track document.   This document is a product of the Internet Engineering Task Force   (IETF).  It represents the consensus of the IETF community.  It has   received public review and has been approved for publication by the   Internet Engineering Steering Group (IESG).  Further information on   Internet Standards is available inSection 2 of RFC 7841.   Information about the current status of this document, any errata,   and how to provide feedback on it may be obtained athttp://www.rfc-editor.org/info/rfc8142.Copyright Notice   Copyright (c) 2017 IETF Trust and the persons identified as the   document authors.  All rights reserved.   This document is subject toBCP 78 and the IETF Trust's Legal   Provisions Relating to IETF Documents   (http://trustee.ietf.org/license-info) in effect on the date of   publication of this document.  Please review these documents   carefully, as they describe your rights and restrictions with respect   to this document.  Code Components extracted from this document must   include Simplified BSD License text as described in Section 4.e of   the Trust Legal Provisions and are provided without warranty as   described in the Simplified BSD License.Gillies                      Standards Track                    [Page 1]

RFC 8142                 GeoJSON Text Sequences               April 2017Table of Contents1. Introduction ....................................................21.1. Requirements Language ......................................22. GeoJSON Text Sequence Format ....................................23. Security Considerations .........................................34. Interoperability Considerations .................................35. IANA Considerations .............................................36. References ......................................................46.1. Normative References .......................................46.2. Informative References .....................................5   Author's Address ...................................................51.  Introduction   Arbitrarily large sequences of values pose a problem for JavaScript   Object Notation (JSON) [RFC7159] that is well explained in the   motivation for JSON text sequences [RFC7464].  The GeoJSON format   [RFC7946] faces the same kind of problem.  Geographic datasets often   run to the tens of thousands or millions of features.  The problem is   often amplified by the presence of large arrays of coordinates for   each of the features.   This document describes a specialization of JSON text sequences.  A   GeoJSON text sequence is a document of arbitrarily large size   containing one or more GeoJSON objects (e.g., multiple GeoJSON texts   that can be produced and parsed incrementally) and not just a single   GeoJSON FeatureCollection, Feature, or Geometry.1.1.  Requirements Language   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and   "OPTIONAL" in this document are to be interpreted as described in   [RFC2119].2.  GeoJSON Text Sequence Format   Defined in prose similar to the description of the JSON text sequence   in [RFC7464], a GeoJSON text sequence is any number of GeoJSON   [RFC7946] texts, each encoded in UTF-8 [RFC3629], preceded by one   ASCII [RFC20] record separator (RS) character, and followed by a line   feed (LF).   The GeoJSON text sequence format conforms to all the rules of   [RFC7464] and adds the following constraint: each JSON text MUST   contain a single GeoJSON object as defined in [RFC7946].Gillies                      Standards Track                    [Page 2]

RFC 8142                 GeoJSON Text Sequences               April 2017   Heterogeneous sequences containing a mix of GeoJSON Geometry,   Feature, and FeatureCollection objects are permitted.  How producers   and parsers of GeoJSON text sequences communicate rules for allowed   GeoJSON types in exchanged sequences is not specified in this   document.3.  Security Considerations   GeoJSON text sequences have no security considerations beyond those   of JSON text sequences [RFC7464] and the GeoJSON format [RFC7946].4.  Interoperability Considerations   The advantage of using ASCII character RS "0x1e" to denote a text is   that sequence producers and parsers need not enforce a canonical form   of GeoJSON.  Any valid GeoJSON, pretty-printed or compact, can be   used in a GeoJSON text sequence.   A variety of parsers designed for newline-delimited sequences of   compact JSON text are deployed on the internet today.  While there is   no canonical form for JSON texts, and pretty-printed and compact   forms are equally valid, GeoJSON text sequences containing compact   GeoJSON texts with no internal newlines are more interoperable with   existing non-standardized parsers.   In a distributed system where order and exactly-once delivery of   messages are difficult to achieve, GeoJSON text sequences that do not   rely on order of texts for extra semantics are more interoperable   than those that do.5.  IANA Considerations   The MIME media type for GeoJSON text sequences is "application/   geo+json-seq" (which uses the suffix established in [RFC8091]).  IANA   has registered it in the "Media Types" registry   <https://www.iana.org/assignments/media-types/>.   Type name:  application   Subtype name:  geo+json-seq   Required parameters:  n/a   Optional parameters:  n/a   Encoding considerations:  binary   Security considerations:  SeeSection 3 of RFC 8142Gillies                      Standards Track                    [Page 3]

RFC 8142                 GeoJSON Text Sequences               April 2017   Interoperability considerations:  SeeSection 4 of RFC 8142   Published specification:RFC 8142   Applications that use this media type: Geographic information      systems (GIS)   Additional information:      Deprecated alias names for this type:  n/a      Magic number(s):  n/a      File extension(s):  n/a      Macintosh file type code(s):  n/a   Person to contact for further information: Sean Gillies      (sean.gillies@gmail.com)   Intended usage:  COMMON   Restrictions on usage:  none   Author:  Sean Gillies (sean.gillies@gmail.com)   Change controller:  IETF6.  References6.1.  Normative References   [RFC20]    Cerf, V., "ASCII format for network interchange", STD 80,RFC 20, DOI 10.17487/RFC0020, October 1969,              <http://www.rfc-editor.org/info/rfc20>.   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate              Requirement Levels",BCP 14,RFC 2119,              DOI 10.17487/RFC2119, March 1997,              <http://www.rfc-editor.org/info/rfc2119>.   [RFC3629]  Yergeau, F., "UTF-8, a transformation format of ISO              10646", STD 63,RFC 3629, DOI 10.17487/RFC3629, November              2003, <http://www.rfc-editor.org/info/rfc3629>.   [RFC7159]  Bray, T., Ed., "The JavaScript Object Notation (JSON) Data              Interchange Format",RFC 7159, DOI 10.17487/RFC7159, March              2014, <http://www.rfc-editor.org/info/rfc7159>.Gillies                      Standards Track                    [Page 4]

RFC 8142                 GeoJSON Text Sequences               April 2017   [RFC7464]  Williams, N., "JavaScript Object Notation (JSON) Text              Sequences",RFC 7464, DOI 10.17487/RFC7464, February 2015,              <http://www.rfc-editor.org/info/rfc7464>.   [RFC7946]  Butler, H., Daly, M., Doyle, A., Gillies, S., Hagen, S.,              and T. Schaub, "The GeoJSON Format",RFC 7946,              DOI 10.17487/RFC7946, August 2016,              <http://www.rfc-editor.org/info/rfc7946>.6.2.  Informative References   [RFC8091]  Wilde, E., "A Media Type Structured Syntax Suffix for JSON              Text Sequences",RFC 8091, DOI 10.17487/RFC8091, February              2017, <http://www.rfc-editor.org/info/rfc8091>.Author's Address   Sean Gillies   Mapbox   Email: sean.gillies@gmail.com   URI:http://sgillies.netGillies                      Standards Track                    [Page 5]