Since version 0.4, EOxServer features an OpenSearch 1.1 interface to allow the exploration of its contents in a different manner than by using the EO-WCS or WMS functionality.

In contrast to EO-WCS and WMS, the OpenSearch interface operates on metadata only and allows a performant view of the data, by using slimmer output formats such as GeoJSON or Atom/RSS XML structures.

In EOxServer, Time and Geo extensions are implemented to limit the spatio-temporal scope of the search. Additionally, EO extension is implemented to support most of the required and recommended best practices of the CEOS OpenSearch Best Practice Document.


To enable the OpenSearch interface in the EOxServer instance, the has to be adjusted and the following line added:

from django.urls import include, re_path

urlpatterns = [
    re_path(r'^opensearch/', include('')),

This adds the necessary URLs and views to the instances setup to expose the interface to the users.

Additionally, the the string "**" has to be added to the COMPONENTS of the file.

The EOXS_OPENSEARCH_FORMATS, EOXS_OPENSEARCH_EXTENSIONS, EOXS_OPENSEARCH_SUMMARY_TEMPLATE, and EOXS_OPENSEARCH_RECORD_MODEL settings in the alter the behavior of the service. The details can be found in the instance configuration section.


The OpenSearch implementation of EOxServer follows a two-step search approach:

  1. the instance can be searched for collections
  2. single collections can be searched for records

For each of those steps, the OpenSearch interface allows two interactions, the description and the``search``. The description operation returns an XML document with service metadata and parametrized endpoints for further searches. The search operation hosts the main searching functionality: the search parameters are sent the service, and the results are encoded end returned.

EO Extension

Since version 0.4 EOxServer prvides implementation of the OpenSearch EO extension. This extension supports most of the required and recommended best practices of the CEOS OpenSearch Best Practice Document.

The EO extension allows the following EO parameters to be added to the Opensearch request:

OpenSearch Search Request EO Parameters
Parameter (Replacement Tag) Description Example
productType (eop:productType) A string that identifies the product type. productType=GES_DISC_AIRH3STD_V005
doi (eo:doi) A Digital Object Identifier “string” identifying the product in the DOI system. doi=doi:10.7666/d.y351065
platform (eo:shortName) The platform / satellite short name. platform=Sentinel-1
platformSerialIdentifier (eo:serialIdentifier) The Platform / satellite serial identifier.  
instrument (eop:shortName) The name of the sensor / instrument. instrument=ASAR
sensorType (eo:sensorType) The sensor type. sensorType=ATMOSPHERIC
compositeType (eo:compositeType) The type of composite product expressed as time period that the composite product covers. compositeType=P10D (P10D) is for 10 days coverage period
processingLevel (eo:processingLevel) The processing level applied to the product.  
orbitType (eo:orbitType) The platform / satellite orbit type. orbitType=LEO (low earth orbit)
spectralRange (eo:spectralRange) The sensor spectral range. spectralRange= INFRARED
wavelengths (eo:discreteWavelengths) A number, set or interval requesting the sensor wavelengths in nanometers.  
hasSecurityConstraints A text informs if the resource has any security constraints. Possible values: TRUE, FALSE hasSecurityConstraints=FALSE
dissemination The dissemination method. dissemination=EUMETCast
recordSchema Metadata model in which additional metadata should be provided inline.  
parentIdentifier (eo:parentIdentifier) The parent of the entry in a hierarchy of resources.  
productionStatus (eo:status) The status of the entry. productionStatus=ARCHIVED
acquisitionType (eo:acquisitionType) Used to distinguish at a high level the appropriateness of the acquisition for “general” use, whether the product is a nominal acquisition, special calibration product or other. Values: NOMINAL, CALIBRATION, OTHER. acquisitionType=CALIBRATION
orbitNumber (eo:orbitNumber) A number, set or interval requesting the acquisition orbit.  
orbitDirection (eo:orbitDirection) the acquisition orbit direction. orbitDirection=ASCENDING
track (eo:wrsLongitudeGrid) the orbit track.  
frame (eo:wrsLatitudeGrid) the orbit frame.  
swathIdentifier (eo:swathIdentifier) Swath identifier. Value list can be retrieved with codeSpace. swathIdentifier=I3 (Envisat ASAR has 7 distinct swaths (I1,I2…I7) that correspond to precise incidence angles for the sensor)
cloudCover (eo:cloudCoverPercentage or eo:cloudCoverPercentage) The cloud coverage percantage. cloudCover=65
snowCover (eo:snowCoverPercentage or eo:snowCoverPercentage) The cloud coverage percantage. cloudCover=65
lowestLocation (eo:lowestLocation) The bottom height of datalayer (in meters).  
highestLocation (eo:highestLocation) The top height of datalayer (in meters).  
productVersion (eo:version) The version of the Product.  
productQualityStatus (eo:productQualityDegradation) An optional field that must be provided if the product passed a quality check. Possible values: NOMINAL and DEGRADED. productQualityStatus=DEGRADED
productQualityDegradationTag (eo:productQualityDegradationTag) The degradations affecting the product.Possible values are mission specific and can be freely defined. productQualityDegradationTag=RADIOMETRY
processorName (eo:processorName) The processor software name.  
processingCenter (eo:processingCenter) The processing center. processingCenter=PDHS-E
creationDate (eo:creationDate) The date when the metadata item was ingested for the first time (i.e. inserted) in the catalogue.  
modificationDate (eo:modificationDate) The date when the metadata item was last modified (i.e. updated) in the catalogue.  
processingDate (eo:processingDate) A date interval requesting entries processed within a given time interval.  
sensorMode (eo:operationalMode) The sensor mode.  
archivingCenter (eo:archivingCenter) The the archiving center.  
processingMode (eo:ProcessingMode) Processing mode. Often referred to as Real Time, Near Real Time etc.  
availabilityTime (eo:timePosition) The time when the result became available (i.e. updated) in the catalogue.  
acquisitionStation (eo:acquisitionStation) The station used for the acquisition.  
acquisitionSubType (eo:acquisitionSubType) The Acquisition sub-type.  
startTimeFromAscendingNode (eo:startTimeFromAscendingNode) Start time of acquisition in milliseconds from Ascending node date.  
completionTimeFromAscendingNode (eo:completionTimeFromAscendingNode) Completion time of acquisition in milliseconds from Ascending node date.  
illuminationAzimuthAngle (eo:illuminationAzimuthAngle) Mean illumination/solar azimuth angle given in degrees.  
illuminationZenithAngle (eo:illuminationZenithAngle) Mean illumination/solar zenith angle given in degrees.  
illuminationElevationAngle (eo:illuminationElevationAngle) Mean illumination/solar elevation angle given in degrees.  
polarisationMode (eo:polarisationMode) The polarisation mode taken from codelist: S (for single), D (for dual), T (for twin), Q (for quad), UNDEFINED polarisationMode=D
polarisationChannels (eo:polarisationChannels) Polarisation channel transmit/receive configuration. polarisationChannels=vertical
antennaLookDirection (eo:antennaLookDirection) LEFT or RIGHT.  
minimumIncidenceAngle (eo:minimumIncidenceAngle) Minimum incidence angle given in degrees.  
maximumIncidenceAngle (eo:maximumIncidenceAngle) Maximum incidence angle given in degrees.  
dopplerFrequency (eo:dopplerFrequency) Doppler Frequency of acquisition.  
incidenceAngleVariation (eo:incidenceAngleVariation) Incidence angle variation  


As mentioned before, EOxServers implementation of OpenSearch adheres to the core, and the time, geo and EO extensions. Thus the interface allows the following parameters when searching for datasets:

OpenSearch Search Request Parameters
Parameter (Replacement Tag) Description Example
q (searchTerms) This parameter is currently not used.  
count Number of returned elements as an integer count=25
startIndex The initial offset to get elements as an integer startIndex=125
format The output format of the search. Currently supported are “json”, “kml”, “atom”, and “rss”. format=json
bbox (geo:box) The geographical area expressed as a bounding box defined as “west,south,east,north” in EPSG:4326 decimal degrees. bbox=-120.0,40.5,-110.5,43.8
lat and lon (geo:lat/geo:lon) latitude and longitude geographical coordinate pair as decimal degrees in EPSG:4326. lat=32.25&lon=125.654
r (geo:radius) The radius parameter used with lat and lon parameters. Units are meters on along the earths surface. lat=32.25&lon=125.654
geom (geo:geometry) A custom geometry encoded as WKT. Supported are POINT, LINESTRING, POLYGON, MULTIPOINT, MULTILINESTRING, and MULTIPOLYGON. The geometry must be expressed in EPSG:4326. geom=POINT(6 10) geom=LINESTRING(3 4,1 5,20 25)
georel (geo:relation)

The geospatial relation of the supplied geometry (or bounding box/circle) and the searched datasets geometry. This parameter allows the following values:

  • “intersects” (default): the passed geometry has to intersect with the datasets geometry
  • “contains”: the passed geometry has to fully enclose datasets geometry. Currently only PostgreSQL/PostGIS supports this relation for distance lookups.
  • “disjoint”: the passed geometry has no spatial overlap with the datasets geometry.
uid (geo:uid) This parameter allows to match a single record by its exact identifier. This is also used to allow links to searches with only a specific item, as used in the atom and RSS formats. uid=MER_FRS_1P_reduced_RGB
start and end (time:start/time:end) The start and end data/time of the given time interval encoded in ISO 8601. start=2006-08-16T09:09:29Z& end=2006-08-17
timerel (time:relation)

The temporal relation between the passed interval and the datasets time intervals. This parameter allows the following values:

  • “intersects”: the given interval has to somehow intersect with the datasets time span.
  • “during”: the given interval has to enclose the datasets time span.
  • “disjoint”: the given interval must have no temporal overlap with the datasets time span.
  • “equals”: the given interval has to exactly match the datasets time span.
cql This parameter allows to perform more complex queries using the Common Query Language (CQL). For more information see the Common Query Language (CQL) documentation.


Unfortunately there are some known issues for certain parameters, especially concerning the geo:radius with the geo:lat and geo:lon: On certain platforms any distance based search results in an abort caused by GEOS, the underlying geometric algorithm library.

All parameters are available for both collection and record searches.

Output Formats

EOxServer supports various output formats to encode the results of the searches. All formats are available for both collection and record searches.


The EOxServer OpenSearch implementation tries to adhere the specification and recommendations for using OpenSearch with either of the two formats. Apart from the usual metadata links are added to the various enabled services like WMS and WCS wherever applicable. When searching for collections a link to the collections OpenSearch description document is also added.


These formats aim to provide only a compact metadata overview of the matched collections and records. Only the identifier, begin/end timestamps and the footprint geometry are included.