Chapter 1:

Introduction and Scope

The NASA-developed Earth Observing System (EOS) Common Metadata Repository (CMR) is a spatial and temporal metadata registry that

stores metadata from a variety of science disciplines and domains —including Climate Variability and Change, Carbon Cycle and Ecosystems, Earth Surface and Interior, Atmospheric Composition, Weather, and Water and Energy Cycles.   The CMR is intended to enable broader use of NASA's EOS data

by providing a more uniform view of NASA’s substantial and diverse data holdings.  Its two primary objectives are to: 1) help science communities in need of data from multiple organizations and disciplines more efficiently use search functions and access data and services; and

2) increase the potential for interoperability with new tools and services.

  As the potential to exchange and inter-operate increases, the value of these resources increases comparably.

The CMR

was designed to accomplish these goals by providing a system with an Application Programming Interface (API).  While the API facilitates the discovery, online access, and delivery of a Data Partner's data holdings; it is the responsibility of the CMR Data Partners to add new metadata, remove old metadata, and modify and control access to existing metadata.  As such, Data Partners retain complete control over what metadata are represented in the CMR at any given time. Client Partners develop client applications that access the CMR API and take advantage of the services made available. These clients, such as Earthdata Search (https://search.earthdata.nasa.gov), CMR open search (https://cmr.earthdata.nasa.gov/opensearch), etc. allow end users to discover data which has been registered in the CMR's holdings; and can be custom made to meet the needs of a general user audience or a specific science application.

It should be noted that the CMR is a continuously evolving metadata system that merges all existing capabilities and metadata from Data Partners and the Global Change Master Directory (GCMD) systems. The CMR elements include all system components, which consist of: CMR itself (formerly the [ECHO]), GCMD, International Data Network (IDN), Earth Science Data and Information System (ESDIS) Metrics System (EMS), all related tools (internal and external), and all Metadata – including the Unified Metadata Model (UMM) concepts, the GCMD Keywords Controlled Vocabulary, and other controlled vocabularies. Thus, this is a living document.  As the CMR matures, updated instructions will be incorporated in later revisions.

NASA's Earth science data has already proven essential to understanding Earth as an integrated system, and other organizations are also providing their Earth science metadata to the CMR for users to search and access.  By simplifying discoverability and accessibility to the CMR’s Earth Science holdings, and fostering interoperability with new tools and services, the user community will enlarge and the pace of scientific discovery and application will accelerate.  For examples of how NASA's Earth science data is helping scientists understand the complexities of our Earth, visit Sensing our Planet and Other Featured Research Articles at https://earthdata.nasa.gov/.

The CMR Concept and Design

NASA's Earth Science Data and Information System (ESDIS)

built the CMR based on Extensible Markup Language (XML) and Web Service technologies. The CMR interfaces with clients and users through

various APIs. The CMR is an open system with published APIs available to the CMR Development and User community. 

Internally, the CMR specifies APIs and provides middleware components

in a layered architecture - including data and service search and access functions

. The figure

below depicts the CMR system context in relation to its public APIs

.

Image Added

CMR System Concept

Key features of the CMR architecture are:

• Ease of Partner Participation – Designed to be low-cost and minimally intrusive, the CMR offers a set of standard ways for

• Partners to interface with the system through provided web UIs and a metadata exchange approach that accommodates existing partners and technology.
• Open System / Published APIs

• – To accommodate independent CMR clients, CMR uses an open system approach and publishes domain APIs. These APIs are independent of the underlying transport protocols used. CMR communicates using WS-I Basic Profile v1.0 compliant web services for

• RESTful web services for CMR ingest, search, and metadata management.

• Evolutionary Development – The CMR system is being developed incrementally to allow for insight and feedback during the development cycle. Industry trends are followed and the use of commercial, off-the-shelf (COTS) products is optimized.

Security

The CMR system requires Secure Sockets Layer (SSL)-based communication from Client Applications to the CMR API, but does not require, secure communication from CMR to a Client Partner's service. Internally, the CMR system is protected through a layer of software and hardware control mechanisms to preserve the integrity of CMR's holdings. When configuring data access fulfillment,

Client Partners are strongly encouraged to utilize SSL communications.

CMR Capability And Functionality

CMR Benefits to Client Partners

The CMR's open system provides earth science data and services to a large, diverse pool of users, enabling scientific community interaction and collaboration. The Client Partners are

benefited in the following ways:

Client Partner Skills

Since the CMR uses platform-independent web service definitions for its API, there are no requirements for a client programming language. All examples in this document use curl; however, the code samples provided could be translated to any web service capable language. 

As a CMR Client Partner, you need to be familiar with basic software development and Service Oriented Architecture (SOA) concepts such as:

• XML and XML Schema (XSD)Image Modified
• Client/Server-based programming (client stubs, remote endpoints, etc.)
• RESTful client and service communication programming
• Service-based Application Programmer's Interface (API)Image Modified

Client Partner Tasks

As a Client Partner who is beginning to integrate with CMR, you should expect to perform the

following tasks,  which are detailed in later sections: 

• Creating and managing user accounts and user access
• Searching for data
• Retrieving data
• Accessing data

CMR System Environments

Three CMR systems are accessible by Client Partners: CMR Operations, CMR UAT and CMR SIT.  Each of these systems is briefly described below.  For additional information,

click on the associated link.

• CMR Operations - The CMR Operations system environment is a publicly accessible server that houses the

• production environment.  The Data Holdings within this system include

• Earth Science data that has been made available to the Earth Science Community by the CMR Data Partners.  This environment is monitored 24/7, updated with enhancements and fixes on a monthly cycle

• , and experiences virtually no down time.
• CMR UAT (User Acceptance Test) - The UAT environment provides a stable test system

• to serve the needs of the CMR Data, Client, and Service

• Partners.The Data Holdings within this system

• consist of whatever the CMR's Data Partners have made available for their own testing purposes.

• Any enhancements and fixes that are

• planned for the Operations Environment are installed in this environment two weeks prior to operations delivery. CMR Partners are encouraged to verify the capabilities when a new release is installed.
• CMR SIT (System Integration Test) The SIT system

• was established in order to facilitate an exchange of ideas and provide

• an initial testing ground for upcoming capabilities.

• There is often very little metadata available in this

• test environment, but it is fully functional. The next operational version is released into this system approximately 1 month before its schedule Operational release date

• .  CMR SIT is a closed, private environment only available to CMR Developers.

Chapter 2: Getting Started

Creating and Managing User Accounts and Access

This chapter will discuss:

• Creating and managing user accounts
• CMR session management - creating, using, and deleting tokens to provide authorization

*Note:  If searching for and retrieving publicly available data is the only desired operation, this section can be skipped and the reader can go proceed straight to Chapter 3.

User Accounts

User accounts are used employed to get enable access to restricted data, manage privileges, and/or to interact with other services and tools provided by the the CMR or ECHO. User accounts for the CMR system are created and manage managed by the Earthdata Login (URS) system. If you need to create an account and don't already have one, please click on Earthdata Login to create one,  click on Earthdata Login and follow the instructions provided. Once created, you can always go back return to Earthdata Login to manage ityour account. If you are part of a Data Provider group or other team, the team administrator can set up permissions for you to access their restricted data. If you need special privileges you can always contact Special privilege requests can be made by contacting the CMR operational team at at support@earthdata.nasa.gov and they can help you. 

Creating and Managing CMR Sessions

The CMR uses tokens in request messages - the http call to CMR - to validate per request who the requester is and what privileges they have. Tokens are used by the CMR to validate both the requester and their privileges for each request message (i.e., the http call to CMR) submitted.  For most searches, a token is not needed because the metadata records are open to everyone. When certain unrestricted and accessible by anyone. However, when specific metadata records are restricted, privileged users require a token is needed so that privileged users can to see and access those records. 

The same token can be used for multiple requests before being deleted.  A  A Session is nothing more than a series of requests that use the same token meaning that you can use the same token for many requests before you delete it. is referred to as a "session."  All tokens expire at the end of a predefined time period . At the time of this writing, the duration is - which is currently fixed at 30 days. Because the token is used to track your session, it must be protected by client applications with the same level of security that you use used for your login name and password.

To conduct a session the normal steps areA normal session is conducted via the following steps:

• Create a token
• Do Perform one or more both of the following tasks in any order:
  • Search for records
  • Retrieve records
• Delete the token 

Creating a Token

Information for requesting a Launchpad Token can be found here. More information on getting access to Launchpad tokens can be found on this guide. 

Once a token is created, you Now that the client partner has created a token, they can search and retrieve records, and as well as conduct other functionality (described in later chapters) through the CMR or ECHO APIs. This functionality is covered in later chapters of this document. Once finished interacting with the CMR the token   When the token is no longer needed, it can be deleted.

Deleting the Token

 A Launchpad token will automatically expire after one hour.

Chapter 3: Searching for metadata

Client partners Currently clients can search the CMR for metadata.  Currently clients can search for collection and granule metadata.  In the future, clients will also be able to search for metadata describing services, visualizations, parameters (variables), and documents.

CMR Environment URLs

The CMR system has three environments: The

The Systems Integration Test environment is where (SIT) Environment provides the CMR development team tests with a safe place to test new functionality. This is the environment that first gets the newest upgrades, but it The newest, untested software and upgrades are are first uploaded here; thus, this environment is the least stable. Once the CMR software has been tested it gets deployed to the User Acceptance Test environment. The environment here is quite stable and it is tested as a system for a couple of weeks sufficiently tested, it gets deployed to the User Acceptance Test (UAT) Environment.  Note that the CMR SIT environment is closed to the public and is intended for internal CMR development only.

The UAT Environment provides a stable environment for testing system software.  The UAT environment is where Open Source developers and Data Partners can deploy new code and/or new metadata for testing before it becomes visible in Operations.  Following a few weeks of successfully testing, the software is deployed to the Operational Environment.

 *Note: before the software is deployed to the operational environment. Client Partners can test their software in either the SIT or UAT environment depending the level of integration and testing. The operational environment is before moving that software to Operations.

The Operational Environment is the live system available to users around the world.  The Operational Environment is also known as Production, Operations, or OPS.

*Note:  All .  All of the examples provided in the rest of the document are using the Systems Integration User Acceptance Test environment.  To   To run the commands in the other environments just replace the SIT URL with either the UAT or OPS URL to use the API in the respective environmentsOperational Environment, replace all instances of cmr.uat.earthdata.nasa.gov with cmr.earthdata.nasa.gov.

CMR Environments

Headers

Headers are a part of HTTP requests and for the CMR they provide information such as the message content of the message (Content-Typecontent type), tokens to allow increased privileges (Echo-Token), the format of the data that gets returned (accept), and tokens to allow increased privileges (EDL Token), etc.  

Content Type

Content-Type is a standard HTTP header that specifies the content type of the body of the request for POST method messages. Search and retrieval requests support the following Content-Types. .               

*Note: If the Content-Type is not specified, XML is assumed.

Content-Type headers

Authorization: Bearer

The Echo-Token allows the CMR to know Authorization: Bearer header allows a user to specify an EDL token so that CMR knows who is making a request. A token must first be generated as described in the Creating a Token section. The Token is in the format of XXXXXXXX-XXXX-Once the requester has the token, the token can be placed into the http header for the necessary API calls.

Authorization:

The Authorization: header allows a user to specify a Launchpad token so that CMR knows who is making a request. A XXXX-XXXX-XXXXXXXXXXXX.  A token must first be generated as described in the previous To Create a Token section. Once the requester has the token, the token can be placed into the http header for the necessary API calls..

Accept Headers

Accept Headers are used in cases where If the caller wishes wants to control in what the format and/or specification by which the data gets returned they can use the Accept header.  The following table lists the valid values.  If this header or an alternative method is not used, the returned outcome will be a reference list of results in XML formatXML results will be returned by default.

Accept Headers

For more information about the types about the accepted header values, please see the CMR API documentation.

Client-Id

Client-Id is an additional is another header that allows the client to specify a their name.  This helps Client Partners are strongly encouraged to use this header for the following reasons:

• Helps the CMR operations team monitor query performance per client
• Aids the CMR operations team in identifying clients who are attempting to contact them for assistance with a request.
• Facilitates NASA in collecting information on how much traffic flows through a client provider and what kind of data interests their users.

Below are some examples depicting how to use headers.  The and it can also make it easier for them to identify your requests if you contact them for assistance.Following are some examples for using the headers. The purple part of the example will be explained in this section, while the rest will be described later:addressed later in the document.

As an alternate to using the Accept header are extensions where Header,  the client can use the Type Received name in the query to get the same results. Instead of using "Accept: application/opendata+json", "opendata" can be used at the end of the main query before parameters are specified. 

Other examples use the DIF 10 specification and the ISO specification respectively.respectively.

To change what is wanted in the type of request just , simply replace the header as needed per the tables with the desired information from the table above.

Results

There are a several of types of results that can be returned.  For each of these types different formats are supported.Listed below are the 3 ways results can be returned, as well as the formats supported by each option:

• A reference list of results

• - XML
• A list of results with partial metadata records

• - XML

• , JSON

• , ATOM, KLM, and CSV (*Note: CSV is supported for granules only

• )
• A list of results with full metadata records

• - XML

• and opendata

The following is an example of a reference list of results

The results specify:

• The number of metadata records

• found by the "hits" tag

• The duration of the query

• in milliseconds

• A list of metadata record results specified by the "reference" tag

With in Within each reference tag, a limited amount of information about the metadata is provided .including:

• The metadata name

• The CMR profile or concept ID -  a CMR generated unique ID.

• The ID is encoded by a letter of the profile or concept (C for collection, G for granule, S for service), followed by a CMR generated number, followed by a "-" and then followed by the ID of the metadata provider.   <letter> <unique-number> "-" <provider-id>
• The exact CMR location

• from which the metadata can be downloaded
• The latest revision number of the metadata record.

The following is an example of a full metadata record list of results in the ECHO 10 specification using the XML format.

The results specify:

• The number of metadata records

• found by the "hits" tag

• The duration of the query

• in milliseconds

• A list of metadata record results specified by the "

• results" tag

Within each result tag three attributes are shown about the , prior to the full metadata record followed by the full metadata record. The attributes display the , the following three attributes are displayed: 

• The CMR concept id (profile ID)

• The specification and format of the metadata

• The revision number of the shown metadata record.  

For  For detailed information about the result specifications and formats available with examples specifications, format options, and examples -  please see the CMR CMR API documentation.

Searching

There are several ways to search the CMR system all using the RESTful principles,  which include employing:

• The API calls and parameters with the GET method
• The API calls and parameters with the

• POST

• method

• A JSON query language with a POST method

• The Alternative Query Language (AQL)

API calls and parameters GET method

The most popular and preferred way method is to use the API calls and parameters with the GET or POST methods. For more detailed documentation information, see the API documentation is located at https://cmr.earthdata.nasa.gov/search/site/search_api_docs.html. 

*Note: The CMR URL character limit is currently set to take roughly 500k characters. Clients using using the GET Search API with query parameters should be careful not to exceed this limit or they will get an HTTP response of 413 FULL HEAD . If a client expects will be returned. Clients who expect that the query url could be extra long so that it exceeds URL could exceed 500k characters , they should use the POST method for searching instead of as opposed to the GET method . First we will describe search using the for searching.

API calls and parameters GET method

The following examples demonstrates the basic search command is shown in the following example :

ui-text-box

Tip
title Example
curl -v -i "https://cmr.uat.earthdata.nasa.gov/search/collections"

The query returns the first 10 publicly available collection results in a reference list using the using  XML format.  As   (Note:  As described in the header section above, in order to see restricted data, if you must have the correct privileges you and will need to use a token).

There are The search parameters that listed below can be applied to provide more functionality.  They are listed below

page

:  

Info
title Page_size - The number of results per page

- the

. The default is set at the minimum value =10.0 and

2000 are

the

minimum and maximum values respectively.  For example:

maximum value =2000.

page_size=100 shows 100 result records per page if that many results exist.

Info
title

page

Page_num - The results page number to return.

For example:

page_num=1

is the first

is the first page of results;  page_num=2 is the second page of results; page_num=10 is the 10th page of results.

Info
title

sort

Sort_key - Indicates one or more elements to

sort on. For example: sort

use for sorting

sort_key[]=platform  (the brackets "[" and "]" may need to be escaped by using the \

character)pretty - Returns formatted - readable - results if set to true.  For example pretty=true.  For

character)

Info
title Pretty- If set to "True" - returns formatted, readable results
pretty = true; (*Note: This flag is used for all the returned examples in this document

this flag is used.

)

Info
title Token
Specifies

token - Specifies

the client token. This is an alternative to using the

Echo-Token

Authorization: Bearer header.

Info
title

echo

Echo-compatible

- This is used

Used by systems requiring ECHO results. To get the best use out of CMR, Client Partners

shouldn't use this parameter

should NOT use this parameter.

These The following search parameters are for collection requests only.:

• include_has_granules - Includes a has-granules tag or attribute in the response so the client knows if the collection encompasses any granules. E.g. include_has_granules=true
• include_granule_counts - Includes a granule-counts tag or attribute in the response with the number of granules represented by the collection. E.g. include_granule_counts=true
• include_facets - Includes a list of facets and their counts at the end of the results. This is mainly used for collection search displays. E.g. include_facets=true
• include_facets with hierarchical_facets - Includes a list of facets preserving the hierarchical order. This is mainly used for collection search displays. E.g include_facets=true&hierarchical_facets=true

 In The next example box we will see depicts a set of examples conducting a basic search with using the search parameters just parameters described below.

• The first

example shows a client wanting to see

• line requests 50 metadata references per page.
• The second

example shows

• line requests 50 metadata references per page using the formatted print.

 The third example shows

•  
• The third line requests page 2 of 20 results per page showing full records in the echo 10 specification using formatted print.
• The fourth

example

• line issues a request including token and client id headers and does a basic search sorting the results using the platform element.  

The  The request returns page 2 results of 20 results per page showing full records in the ISO 19115 specification using the XML format in a formatted fashion. As one can see the ? character separates the URL from the search parameters and the search parameters are separated by the & character. The parameters can be in any order.

ui-text-box

Tip
title Example
curl -v -i "https://cmr.uat.earthdata.nasa.gov/search/collections?page_size=50" curl -v -i "https://cmr.uat.earthdata.nasa.gov/search/collections?page_size=50&pretty=true" curl -v -i "https://cmr.uat.earthdata.nasa.gov/search/collections.echo10?page_num=2&page_size=20&pretty=true" curl -v -i -H "Echo-Token: 75E5CEBE-6BBB-2FB5-A613-0368A361D0B6Authorization: Bearer XXXX" -H "Client-Id: Test_Team"  "https://cmr.uat.earthdata.nasa.gov/search/collections.iso?sort_key\[\]=platform&page_num=2&page_size=20&pretty=true"  =20&pretty=true"

*Note: The "?" character separates the URL from the search parameters and the search parameters are separated from each other by the "&" character. The parameters can be in any order.

The previous examples all demonstrated demonstrate collections searches for collections. The same search parameters apply to granules if it isn't , unless it is explicitly stated that a parameter applies only to collections. To conduct a granule search, just simply replace collections with granules in the URL.  Following   In the box below are the same four search requests just that are listed above but for granules instead of collections.in the box above,  only granules has been substituted for collections.

ui-text-box

Tip
title Example
curl -v -i "https://cmr.uat.earthdata.nasa.gov/search/granules?page_size=50" curl -v -i "https://cmr.uat.earthdata.nasa.gov/search/granules?page_size=50&pretty=true" curl -v -i "https://cmr.uat.earthdata.nasa.gov/search/granules.echo10?page_num=2&page_size=20&pretty=true" curl -v -i -H "Echo-token: 75E5CEBE-6BBB-2FB5-A613-0368A361D0B6Authorization: Bearer XXXX" -H "Client-Id: Test_Team"  "https://cmr.earthdata.nasa.gov/search/granules.iso?sort_key\[\]=platform&page_num=2&page_size=20&pretty=true"

Now to refine our searches we can use another The search can be refined using the set of search parameters documented in the table below. These parameters support collection searches and most . Most of these parameters have the brackets next to them and may need to be escaped (\[\]) depending on the language used or how the method by which the query is being sent.  All   All of CMR time search parameters (temporal, updated_since, revision_date, and equatorand equator_crossing_date) formats are specified as yyyyas yyyy-MM-ddTHH:mm:ss.SSSZ format. Where ;  Where yyyy is year; MM is month; dd is day; T is the date time separator character; HH is the hour; mm is the minute; ss is the second; SSS is the milliseconds the milliseconds (the .SSS can be omitted); and Z specifies Zulu time.  

Tip
title Example
January 2, 2000 at 4 minutes and 5 seconds

and 4 minutes

past 3

O

o'clock in the morning Zulu time is represented as 2000-01-02T03:04:05Z.

Documented in the table below are collection supported search parameters:

*Note:    To get the complete and most up to date set of parameters please see ,  visit https://cmr.earthdata.nasa.gov/search/site/search_api_docs.html.

Search Parameters	Example	Notes	Supports Pattern Option	Supports Case Insensitivity Option	Supports AND Option (ALL values have to be present within an element)	Supports OR Option (ANY value has to be present within an element)
concept_id	concept_id\[\]=C123456-LPDAAC_ECS

 

		NO	NO	NO	NO
echo_collection_id	echo_collection_id\[\]=C1000000001-CMR_PROV2	uses concept_id	NO	NO	NO	NO
entry_title	entry_title\[\]=this is a title

 

		YES	YES	NO	NO
dataset_id	dataset_id\[\]=this is a title	uses entry_title	N/A	N/A	NO	NO
entry_id	entry_id\[\]=SHORT_V5

 

		NO	NO	NO	NO
dif_entry_id	dif_entry_id\[\]=SHORT_V5	matches either entry_id or associated difs	NO	NO	NO	NO
archive_center	archive_center\[\]=SEDAC

 

	YES	YES	NO	NO
temporal	temporal\[\]=2000-01-01T10:00:00Z,2010-03-10T12:00:00Z,30,60 or temporal\[\]=2000-01-01T10:00:00Z/P10Y2M10DT2H,30,60	format is: begin datetime, end datetime, period, duration or: begin datetime/ISO 8601 time interval One can leave out the begin time or end time or both the period and duration ranges are inclusive unless otherwise specified	N/A	N/A	NO	NO
project	project\[\]=ESI

 

	YES	YES	YES	NO
campaign	campaign\[\]=ESI	uses project	YES	YES	YES	NO
updated_since	updated_since=2000-01-01T01:00:00Z	The time is inclusive.	NO	N/A	NO	NO
revision_date	revision_date\[\]=2000-01-01T01:00:00Z,2010-01-01T12:34:56Z revision_date\[\]=2000-01-01T01:00:00Z,	The beginning or ending date time can be left off, but comma must remain. Inclusive boundary search	NO	N/A	YES	NO
processing_level_id	processing_level_id\[\]=1B

 

		YES	YES	NO	NO
platform	platform\[\]=AQUA	platform short name	YES	YES	YES	NO
instrument	instrument\[\]=CERES	instrument short name	YES	YES	YES	NO
sensor	sensor\[\]=CCD	sensor short name	YES	YES	YES	NO
spatial_keyword	spatial_keyword\[\]=VA

 

		YES	YES	YES	NO
science_keywords	science_keywords\[0\]\[category\]=EARTH SCIENCE&science_keywords\[0\]\[topic\]=BIOLOGICAL CLASSIFICATION&science_keywords\[0\]\[term\]=ANIMALS/VERTEBRATES&science_keywords\[0\]\[variable-level-1\]=MAMMALS&science_keywords\[0\]\[variable-level-2\]=CARNIVORES&science_keywords\[0\]\[variable-level-3\]=BEARS	There is a hierarchy for science keywords. These can be ANDed together which is the default or ORed.	NO	NO	YES	YES
two_d_coordinate_system_name	two_d_coordinate_system_name\[\]=Alpha

 

		YES	NO	NO	NO
two_d_coordinate_system[name]	two_d_coordinate_system\[name\]=Alpha	alias of two_d_coordinate_system_name but does not support pattern	NO	NO	NO	NO
collection_data_type	collection_data_type\[\]=NEAR_REAL_TIME	valid values for near real time: "NEAR_REAL_TIME": "near_real_time", "nrt", "NRT", "near real time", "near-real time", "near-real-time", "near real-time" ALSO uses OTHER, SCIENCE QUALITY	NO	YES	NO	NO
provider	provider=ASF

 

	YES	YES	YES	NO
short_name	short_name=MINIMAL

 

		YES	YES	YES	NO
version	version=1	used together with short_name	YES	YES	YES	NO
polygon	polygon=10,10,30,10,30,20,10,20,10,10	Polygon points are provided in counter-clockwise order. The last point should match the first point to close the polygon. The values are listed comma separated in longitude latitude order, i.e. lon1, lat1, lon2, lat2, lon3, lat3, and so on.	N/A	N/A	NO	NO
bounding_box	bounding_box=-10,-5,10,5	Bounding boxes define an area on the earth aligned with longitude and latitude. The Bounding box parameters must be 4 comma-separated numbers: lower left longitude, lower left latitude, upper right longitude, upper right latitude.	N/A	N/A	NO	NO
point	point=100,20	Search using a point involves using a pair of values representing the point coordinates as parameters. The first value is the longitude and second value is the latitude.	N/A	N/A	NO	NO
line	line=-0.37,-14.07,4.75,1.25,25.13,-15.51	Lines are provided as a list of comma separated values representing coordinates of points along the line. The coordinates are listed in the format lon1, lat1, lon2, lat2, lon3, lat3, and so on.	N/A	N/A	NO	NO
keyword	keyword=alpha

 

	By default keyword searches are case insensitive and support wild cards ? and *. The following elements are searched by a keyword search: Concept ID Provider ID Entry Title data type short name and long name abstract version and version description processing level id science keywords archive centers additional attribute (names, data types, values, and descriptions) spatial keywords temporal keywords associated DIFs project short and long names platform short and long names instrument short & long names and techniques sensor short & long names and techniques characteristic names and descriptions two d coordinate system names	NO	NO	NO	NO
online_only	online_only=true	valid values: true, false	NO	NO	NO	NO
downloadable	downloadable=true	valid values: true, false	NO	NO	NO	NO
browse_only	browse_only=false	valid values: true, false	NO	NO	NO	NO
browsable	browsable=true	valid values: true, false	NO	NO	NO	NO

Collection Search Parameters

Documented in the table below are granule supported search parameters.

Search Parameters	Example	Notes	Supports Pattern Option	Supports Case Insensitivity Option	Supports AND Option (ALL values have to be present within an element)	Supports OR Option (ANY value has to be present within an element)
granule_ur	granule_ur\[\]=SC:AST_L1B.003:2082836137

 

	NO	NO	NO	NO
producer_granule_id	producer_granule_id\[\]=AST_L1B_00304092000162008_20110111183559_9769.hdf

 

	NO	NO	NO	NO
readable_granule_name	readable_granule_name\[\]=SC:AST_L1B.003:2082836137	matches either granule ur or producer granule id	NO	NO	NO	NO
online_only	online_only=true	valid values: true, false	NO	NO	NO	NO
downloadable	downloadable=true	valid values: true, false	NO	NO	NO	NO
attribute	attribute\[\]=UpperLeftQuadCloudCoverage attribute\[\]=float,UpperLeftQuadCloudCoverage,25.5,30 attribute\[\]=float,UpperLeftQuadCloudCoverage,25.5, attribute\[\]=float,UpperLeftQuadCloudCoverage,,30 attribute\[\]=int,UpperLeftQuadCloudCoverage,4 attribute\[\]=float,UpperLeftQuadCloudCoverage,25.5,30&options\[attribute\]\[or\]=true attribute\[\]=float,UpperLeftQuadCloudCoverage,25.5,30&options\[attribute\]\[exclude_boundry\]=true attribute\[\]=float,UpperLeftQuadCloudCoverage,25.5,30&options\[attribute\]\[exclude_collection\]=true	full syntax:name - attribute name only full syntax: value type, attribute name, min value, max value - range search, can leave off beginning or ending of range, but comma is still needed. Ranges are inclusive. If this is not desired set to true the exclude_boundry option. full syntax:value type, attribute name, value - single value attribute. These searches include the granule collection - if this is not desired set to true the option exclude_collection	NO	NO	YES	YES
polygon	polygon=10,10,30,10,30,20,10,20,10,10	Polygon points are provided in counter-clockwise order. The last point should match the first point to close the polygon. The values are listed comma separated in longitude latitude order, i.e. lon1, lat1, lon2, lat2, lon3, lat3, and so on.	N/A	N/A	NO	NO
bounding_box	bounding_box=-10,-5,10,5	Bounding boxes define an area on the earth aligned with longitude and latitude. The Bounding box parameters must be 4 comma-separated numbers: lower left longitude, lower left latitude, upper right longitude, upper right latitude.	N/A	N/A	NO	NO
point	point=100,20	Search using a point involves using a pair of values representing the point coordinates as parameters. The first value is the longitude and second value is the latitude.	N/A	N/A	NO	NO
line	line=-0.37,-14.07,4.75,1.25,25.13,-15.51	Lines are provided as a list of comma separated values representing coordinates of points along the line. The coordinates are listed in the format lon1, lat1, lon2, lat2, lon3, lat3, and so on.	N/A	N/A	NO	NO
orbit_number	orbit_number=10 orbit_number=0.5,1.5	value or range	NO	NO	NO	NO
equator_crossing_longitude	equator_crossing_longitude=90 equator_crossing_longitude=170,-170	value or range	NO	NO	NO	NO
equator_crossing_date	equator_crossing_date=2000-01-01T10:00:00Z,2010-03-10T12:00:00Z	date range searches can be expressed using ISO 8601	NO	NO	NO	NO
updated_since	updated_since=2015-01-01T13:12:11Z

 

		NO	N/A	NO	NO
revision_date	revision_date\[\]=2015-03-04T16:15:14Z,2015-04-04T17:18:19Z revision_date\[\]=2015-03-04T16:15:14Z,	The beginning or ending date time can be left off, but comma must remain. Inclusive boundary search	NO	N/A	YES	NO
cloud_cover	cloud_cover=-70.0,120.0	The beginning or ending range can be left off, but comma must remain. Inclusive boundary search	NO	N/A	NO	NO
platform	platform\[\]=AQUA	platform short name	YES	YES	YES	NO
instrument	instrument\[\]=CERES	instrument short name	YES	YES	YES	NO
sensor	sensor\[\]=CCD	sensor short name	YES	YES	YES	NO
project	project\[\]=ESI

 

	YES	YES	YES	NO
campaign	campaign\[\]=ESI	uses project	YES	YES	YES	NO
concept_id	concept_id\[\]=G123456-LPDAAC_ECS concept_id\[\]=C123456-LPDAAC_ECS	This finds either the granule or the collection parent record - the difference is in the ID (C vs G)	NO	NO	NO	NO
echo_granule_id	echo_granule_id\[\]=G1000000001-CMR_PROV2	uses concept_id	NO	NO	NO	NO
collection_concept_id	collection_concept_id\[\]=C123456-LPDAAC_ECS

 

		NO	NO	NO	NO
echo_collection_id	echo_collection_id\[\]=C123456-LPDAAC_ECS

 

		NO	NO	NO	NO
day_night_flag	day_night_flag=day	valid values are day, night, unspecified	YES	YES	NO	NO
day_night	day_night=unspecified	valid values are day, night, unspecified - uses the day-night-flag element.	YES	YES	NO	NO
two_d_coordinate_system	two_d_coordinate_system\[\]=wrs-1:5,10:8-10,0-10:8,12	see API docs for description	NO	NO	NO	NO
grid	grid\[\]=wrs-1:5,10:8-10,0-10:8,12	uses two_d_coordinate_system element	NO	NO	NO	NO
provider	provider=ASF

 

	YES	YES	YES	NO
short_name	short_name=MINIMAL

 

	YES	YES	YES	NO
version	version=1	used together with short_name	YES	YES	YES	NO
entry_title	entry_title\[\]=this is a title

 

	YES	YES	NO	NO
temporal	temporal\[\]=2000-01-01T10:00:00Z,2010-03-10T12:00:00Z,30,60 or temporal\[\]=2000-01-01T10:00:00Z/P10Y2M10DT2H,30,60	format is: begin datetime, end datetime, period, duration or: begin datetime/ISO 8601 time interval One can leave out the begin time or end time or both the period and duration ranges are inclusive unless otherwise specified	N/A	N/A	NO	NO
exclude	exclude\[echo_granule_id\]\[\]=G100000006-CMR_PROV exclude\[concept_id\]\[\]=G100000006-CMR_PROV exclude\[concept_id\]\[\]=C100000006-CMR_PROV

 

exclude metadata records by echo_granule_id, concept id, or parent concept id.

NO

NO

NO

NO

                                                                                                                                                          

Granule Search Parameters

In the The following example we wish demonstrates a request to find all collection metadata records that contain an AQUA platform and we would like the to see granule.  It further requests that only a formatted reference list of results that contain contains 20 references be displayed.

Tip
title Example
UI Text Box
curl -v -i -H "Echo-Token: 75E5CEBE-6BBB-2FB5-A613-0368A361D0B6Authorization: Bearer XXXX" -H "Client-Id: Test_Team"  "https://cmr.uat.earthdata.nasa.gov/search/collections?platform\[\]=AQUA&page_size=20&pretty=true"

In the next example we wish to find all The following example demonstrates a request to find collection metadata records that contain an AQUA or an AURA platform and we would like the to see granule.  It further requests that only a formatted reference list of results that contain contains 20 references be displayed.

ui-text-box

Tip
title Example
curl -v -i -H "Echo-Token: 75E5CEBE-6BBB-2FB5-A613-0368A361D0B6Authorization: Bearer XXXX" -H "Client-Id: Test_Team"  "https://cmr.uat.earthdata.nasa.gov/search/collections?platform\[\]=AQUA&platform\[\]=AURA&page_size=20&pretty=true"

Certain There are a couple of extra options that certain search parameters have additional options to aid the user.  To use these options the syntax   The syntax to employ them is: options[parameter name][option_key]=value.

• Parameter name is the

name of the

• search parameter to be affected

such as

• (ex: platform).
• Value is

either

• set to "true" or "false".

 Option

•  
• Option_key is one of the following:

Option name	Description
ignore_case	If "ignore_case" is set to true the search will be case insensitive and if set to false the search will be case sensitive.  The default value is true. E.g. ignore_case=true - the search will match on both AQUA and aqua
pattern	This is the wildcard capability. If "pattern" is set to true the CMR will treat '*' as matches zero or more characters and '?' matches any single character. For example: platform[]=AQUA will match only on the value 'AQUA'.  if platform[]=A?U*&options[platform][pattern]=true platforms containing A followed by any alphanumeric character followed by U followed by any number of alphanumeric characters will be found.  So AQUA, ASUBB, ADUSD34H, AUU, etc. will all be found. The pattern option defaults to false.
and	If "and" is set to true and if multiple values are listed for the parameter, the metadata records must contain ALL of these values in order to match. The default is false meaning metadata records that match ANY of the values will match.
or	This option only applies to granule attributes or science-keyword searches. If "or" is set to true, the search will find records that match any of the attributes. The default for this option is false.

Extra Options

The The following is an example demonstrates the use of using additional options in conjunction with the platform search parameter.  This example will   A user would make the request in the box below to find any platform that matches begins with "A" followed by any number of alphanumeric characters and ends with "A. This will find both platforms of ".   AQUA and AURA . would both be located and returned with the results.

ui-text-box

Tip
title Example
curl -v -i -H "Echo-Token: 75E5CEBE-6BBB-2FB5-A613-0368A361D0B6Authorization: Bearer XXXX" -H "Client-Id: Test_Team"  "https://cmr.uat.earthdata.nasa.gov/search/collections.echo10?platform\[\]=A*A&options\[platform\]\[pattern\]=true&pretty=true"

This next example demonstrates a user looking to find records that only contain an instrument that matches in the box below depicts a request entered to search for records exclusively contains an instrument matching "HELLO" in uppercase letters.

ui-text-box

Tip
title Example
curl -v -i -H "Echo-Token: 75E5CEBE-6BBB-2FB5-A613-0368A361D0B6Authorization: Bearer XXXX" -H "Client-Id: Test_Team"  "https://cmr.uat.earthdata.nasa.gov/search/collections.echo10?instrument\[\]=HELLO&options\[instrument\]\[ignore-case\]=false&pretty=true"

 

Besides science_keywords, if any of the parameters that are searched are repeated, the metadata records that have ANY of the values will match.  The   The following example demonstrates that the CMR system will match any metadata record containing either valueeither concept id.

 

ui-text-box

Tip
title Example
curl -v -i -H "Echo-Token: 75E5CEBE-6BBB-2FB5-A613-0368A361D0B6Authorization: Bearer XXXX" -H "Client-Id: Test_Team"  "https://cmr.uat.earthdata.nasa.gov/search/collections.iso?concept_id\[\]=C123456-LPDAAC_ECS&concept_id\[\]=C123457-LPDAAC_ECS&pretty=true"

 

For a complete set of examples using all of the search parameters please see , visit the API documentation link at: https://cmr.earthdata.nasa.gov/search/site/search_api_docs.html

API calls and parameters POST method

The API using the POST method is the same as with the GET method, with the exception being the method of: 1) The method name used is POST instead of GET;  and 2) the parameters are in the body of the message without a length constraint instead of as opposed to existing in the URL string.  Using   The following example uses the curl command the following example and shows the query.xml file that contains the query we want to execute followed by request.  The subsequent example depicts the curl search request. In As long as syntax remains the same in the query.xml file, the parameters can be left as one long set or formatted to be more easily read - so long as syntax remains the same. Also notice in this example we did not escape . 

*Note: Notice the brackets ([ ]) were not escaped in this example.

query.xml:

Notice in *Note: In this specific instance that , the Content-Type header is not used.  Don't use it,   This is deliberate as it will cause an error.  

JSON query language with a POST method

For those who understand the JSON format, the The CMR provides a JSON RESTful interface. The elements that can be searched are the same as already described above, but this interface is for applicable only to collection searches only. This searching search method does provide additional functionality of provides additional functionality in conducting a search by using conditions (AND, OR, NOT) against the elements to conduct a search.  See the JSON schema https://cmr.situat.earthdata.nasa.gov/search/site/JSONQueryLanguage.json for more details.  The example provided below demonstrates a query with consisting of conditions and uses several elements.  

curl -XPOST -H "Content-Type: application/json" -H "Client-Id: GCMD" https://cmr.situat.earthdata.nasa.gov/search/collections
-d '{"condition": { "and": [{ "not": { "or": [{ "provider": "TEST" },
{ "and": [{ "project": "test-project",
"platform": "mars-satellite" }]}]}},
{ "bounding_box": [-45,15,0,25],
"science_keywords": { "category": "EARTH SCIENCE" }}]}}'

Alternative Query Language (AQL)

The CMR supports the ECHO Alternative Query Language (AQL) if a client wishes to use this capability. While and is available to clients.  However,  while the AQL is supported, it is not being enhanced nor modified to take advantage of will not mature or be integrated with new CMR features. For a very detailed explanation and examples of AQL with examples of how to use it, please see the , refer to the ECHO AQL documentation.  

Chapter 4: Retrieving Metadata

There are several ways of retrieving metadata.  The first way consists of getting ways of retrieving metadata:

• Retrieve a result list consisting of full metadata records.

• While this has

• been demonstrated

• above, a example has been replicated here for convenience.

  Tip
  title Example
  curl -v -i "https://cmr.

• uat.earthdata.nasa.gov/search/collections.native?pretty=true" curl -v -i "https://cmr.

• uat.earthdata.nasa.gov/search/granules.native?pretty=true"

The response is a result list of full metadata records.  

• Use the concept id to retrieve a record

• : The syntax

• is https://cmr.

• uat.earthdata.nasa.gov/search/concepts/<conceptid>. 

• 
  The concept id/revision number if a specific revision of a metadata record is wanted

• : The syntax

• is https://cmr.

• uat.earthdata.nasa.gov/search/concepts/<conceptid>/<revision number>.

• Tip
  title Example

• curl -v "https://cmr.

• uat.earthdata.nasa.gov/search/concepts/C1000000803-DEV08" curl -v "https://cmr.

• uat.earthdata.nasa.gov/search/concepts/C1000000803-DEV08/7" curl -v "https://cmr.

• uat.earthdata.nasa.gov/search/concepts/G23447-ASF/8

  
  

• The CMR supports retrieving metadata

• records using different specifications and formats, which are listed in the table below:

Supported Standards

Below are several examples using the supported standards mime types.  The first example is retrieving a :

• Ex 1: Retrieves a granule metadata record in the JSON format.

•  
  
• Ex 2: Retrieves a granule metadata record with a revision of 8 in the ISO specification.

•   
• Ex 3: Retrieves a collection metadata record with a revision of 7 in the DIF 10 specification. (*Note: If the record was sent and stored using the ECHO10 specification, that record will be translated to the DIF 10 specification

• and returned to the caller.)     

• Ex 4: Lists a granule record using the native

• option with the pretty print option turned on.

• The native option lists the metadata in the specification it was sent and stored within the CMR.

  Tip
  title Example

• curl -v "https://cmr.

• uat.earthdata.nasa.gov/search/concepts/G23447-ASF.json"  curl -v "https://cmr.

• uat.earthdata.nasa.gov/search/concepts/G23447-ASF/8.iso" curl -v "https://cmr.

• uat.earthdata.nasa.gov/search/concepts/C1000000803-DEV08/7.dif10" curl -v "https://cmr.

• uat.earthdata.nasa.gov/search/concepts/G23447-ASF.native?pretty=true"

  
  

Chapter 5: Accessing data

After identifying data of interest through searches, there There are a couple variety of ways to get access to it. The first way is to access the data providers site advertised by access the data of interest from the response of a search query:

1. Access the data provider's site via the landing page in the collection or granule and follow their instructions for data retrieval. Note: This

1. information is not required and may not be present.

1. 
    
2.  Order the data through the Earthdata Search system, found at https://search.earthdata.nasa.gov.