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Note
titleHere are some technical essentials to start using the API

  • The base URL for the API is https://cloudecloud.europeanapsnc.eupl/api

  • To use the API one needs you will need a user account. Obtain one from the Europeana Cloud team.

  • The part of the Tutorial below gives examples and demonstrates the API calls using the popular command line utility cURL for submitting HTTP requests. One can use other tools to submit HTTP requests if desired.

  • You might be interested in a Java client libraries - there are available in Europeana Cloud source code repository.

  • In the examples below user credentials are provided using the --user parameter

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Code Block
languagebash
curl -X POST -H "Content-Type: application/json" --user user:password -d '{
    "organisationWebsiteURL": "http://www.man.poznan.pl",
    "organisationWebsite": "Poznan Supercomputing and Networking Center Affiliated to Institute of Bioorganic Chemistry Polish Academy of Science",
    "officialAddress" : "ul. Jana Pawła II 10, Poznań",
    "digitalLibraryURL" : "http://lib.psnc.pl/dlibra",
    "digitalLibraryWebsite": "Institutional Repository",
    "organisationName": "Poznan Supercomputing and Networking Center Affiliated to Institute of Bioorganic Chemistry Polish Academy of Science",
    "remarks": "Integrating and developing the information infrastructure for science",
    "contactPerson": "office@man.poznan.pl"
}' -i https://cloudecloud.europeanapsnc.eupl/api/data-providers?providerId=PSNC

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Code Block
languagebash
 curl -X GET  -H "Accept: application/json" --user user:password -i https://cloudecloud.europeanapsnc.eupl/api/data-providers/PSNC

 

The response should look like this:

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Code Block
languagebash
curl -X POST --user user:password -i https://cloudecloud.europeanapsnc.eupl/api/cloudIds?providerId=PSNC\&recordId=exampleLocalRecord 

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Code Block
curl -X POST --user user:password https://cloudecloud.europeanapsnc.eupl/api/cloudIds?providerId=exampleProvider

 

The newly created global identifier and a local one can be found in the response:

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Code Block
curl -X GET  -H "Accept: application/json" --user user:password -i https://cloudecloud.europeanapsnc.eupl/api/data-providers/PSNC/cloudIds

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Code Block
curl -X POST -H "Accept: application/json" --user user:password -H "Content-Type: application/x-www-form-urlencoded" -d 'providerId=PSNC' -i https://cloudecloud.europeanapsnc.eupl/api/records/X67WPA7NGCZUKLACPWU3BORRGQUWTKSZNZDICEGZS6IXTRMINOIQ/representations/TIFF

curl -X POST -H "Accept: application/json" --user user:password -H "Content-Type: application/x-www-form-urlencoded" -d 'providerId=PSNC' -i https://cloudecloud.europeanapsnc.eupl/api/records/X67WPA7NGCZUKLACPWU3BORRGQUWTKSZNZDICEGZS6IXTRMINOIQ/representations/thumbnail

curl -X POST -H "Accept: application/json" --user user:password -H "Content-Type: application/x-www-form-urlencoded" -d 'providerId=PSNC' -i https://cloudecloud.europeanapsnc.eupl/api/records/X67WPA7NGCZUKLACPWU3BORRGQUWTKSZNZDICEGZS6IXTRMINOIQ/representations/EDM

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When successful, the response will have HTTP status code 201 (Created). Note that when a new representation is created, it is automatically assigned a new version. This new version can be reached directly using a URL which is returned in the location field of the response header. The URL will be of the following format:

Code Block
	https://cloudecloud.europeanapsnc.eupl/api/records/X67WPA7NGCZUKLACPWU3BORRGQUWTKSZNZDICEGZS6IXTRMINOIQ/representations/thumbnail/versions/cd9f0050-3dea-11e6-b03d-fa163e8d4ae3

 

Subsequent versions of a representation can be created further in the future, for example to reflect ongoing work on a file.

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Code Block
curl -X POST --user user:password -H "Content-Type: multipart/form-data" -F "mimeType=application/png" -F "data=@thumbnail.png" https://cloudecloud.europeanapsnc.eupl/api/records/X67WPA7NGCZUKLACPWU3BORRGQUWTKSZNZDICEGZS6IXTRMINOIQ/representations/thumbnail/versions/cd9f0050-3dea-11e6-b03d-fa163e8d4ae3/files

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URI of the newly added file will be returned in the location field of the response header:

Code Block
https://cloudecloud.europeanapsnc.eupl/api/records/X67WPA7NGCZUKLACPWU3BORRGQUWTKSZNZDICEGZS6IXTRMINOIQ/representations/thumbnail/versions/cd9f0050-3dea-11e6-b03d-fa163e8d4ae3/files/1df7a491-8d8a-4180-9eb0-cd18c52a4b81

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Code Block
curl -X POST --user user:password -i https://cloudecloud.europeanapsnc.eupl/api/records/X67WPA7NGCZUKLACPWU3BORRGQUWTKSZNZDICEGZS6IXTRMINOIQ/representations/thumbnail/versions/cd9f0050-3dea-11e6-b03d-fa163e8d4ae3/persist

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Code Block
curl -X DELETE --user user:password https://cloudecloud.europeanapsnc.eupl/api/records/X67WPA7NGCZUKLACPWU3BORRGQUWTKSZNZDICEGZS6IXTRMINOIQ/representations/thumbnail/versions/cd9f0050-3dea-11e6-b03d-fa163e8d4ae3/

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Code Block
curl -X POST --user user:password -H "Content-Type: application/x-www-form-urlencoded" -d 'dataSetId=exampleDataSet' -i https://cloudecloud.europeanapsnc.eupl/api/data-providers/PSNC/data-sets

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Code Block
curl -X POST --user user:password -H "Content-Type: application/x-www-form-urlencoded" -d 'cloudId=X67WPA7NGCZUKLACPWU3BORRGQUWTKSZNZDICEGZS6IXTRMINOIQ&representationName=thumbnail&version=cd9f0050-3dea-11e6-b03d-fa163e8d4ae3' -i https://cloudecloud.europeanapsnc.eupl/api/data-providers/PSNC/data-sets/exampleDataSet/assignments

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Code Block
curl -X DELETE --user user:password -H "Content-Type: application/x-www-form-urlencoded" -i https://cloudecloud.europeanapsnc.eupl/api/data-providers/PSNC/data-sets/exampleDataSet/assignments?cloudId=X67WPA7NGCZUKLACPWU3BORRGQUWTKSZNZDICEGZS6IXTRMINOIQ\&representationName=thumbnail

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Code Block
curl -X GET -H "Accept: application/xml" --user user:password -i https://cloudecloud.europeanapsnc.eupl/api/data-providers/PSNC/data-sets/exampleDataSet/

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Code Block
curl -X DELETE -H "Accept: application/json" --user user:password -i https://cloudecloud.europeanapsnc.eupl/api/data-providers/PSNC/data-sets/exampleDataSet/

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In the current version access is managed on the level of filesversions. That means that data owners can grant or revoke access to  versions (and the files associated to the version) owned by them. In future versions we will consider extending permission management also to higher levels: representations, records or datasets.

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Code Block
curl -X POST --user user:password -i https://cloudecloud.europeanapsnc.eupl/api/records/X67WPA7NGCZUKLACPWU3BORRGQUWTKSZNZDICEGZS6IXTRMINOIQ/representations/thumbnail/versions/cd9f0050-3dea-11e6-b03d-fa163e8d4ae3/permit

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Code Block
curl -X POST --user user:password https://cloudecloud.europeanapsnc.eupl/api/records/X67WPA7NGCZUKLACPWU3BORRGQUWTKSZNZDICEGZS6IXTRMINOIQ/representations/thumbnail/versions/cd9f0050-3dea-11e6-b03d-fa163e8d4ae3/permissions/permission/users/anotherUser

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Friendly URLs

 

Sometimes it is hard for a client to get the global identifier of a record, generated version name of a representation and generated filename. On the other hand the client has got a local record identifier which is well known. The same may be in case of a filename. In order to access files without retrieving the hard to remember identifiers and names mechanism of friendly URLs was introduced. The idea behind it is to use in URLs well known values (identifiers, names, etc.) always in the same way. Here we will go through the tutorial steps using friendly URLs where it is possible.

 

Record

 

Normally when you know the cloud identifier of a record you can access it using URL like this:

 

Code Block
https://cloudecloud.europeanapsnc.eupl/api/records/X67WPA7NGCZUKLACPWU3BORRGQUWTKSZNZDICEGZS6IXTRMINOIQ

 

If you remember from the beginning of this tutorial, this record was created for PSNC data provider together with local identifier which was exampleLocalRecord. So now we have only two values: name of the data provider (PSNC) and identifier used by this data provider (exampleLocalRecord). To get access to this record in Europeana Cloud using just these two values we can use friendly URL like this:

 

Code Block
curl -X GET -H "Accept: application/json" --user user:password -i https://cloudecloud.europeanapsnc.eupl/api/data-providers/PSNC/records/exampleLocalRecord

 

Representation

 

Sometimes it is necessary to get access to a specific representation. Again, instead of retrieving the global identifier we can use well known values like data provider name, local record identifier and representation name. Let's display information about the TIFFrepresentation using the friendly URL:

 

Code Block
curl -X GET -H "Accept: application/json" --user user:password -i https://cloudecloud.europeanapsnc.eupl/api/data-providers/PSNC/records/exampleLocalRecord/representations/TIFF

 

File

 

If you do not want to have files with names generated by the system there is possibility to specify the name in the insert request. We can add a file to TIFF representation and specify a name for it like this:

 

Code Block
curl -X POST --user user:password -H "Content-Type: multipart/form-data" -F "mimeType=image/tiff" -F "data=@tiff.tiff" -F "fileName=abc" https://cloudecloud.europeanapsnc.eupl/api/records/X67WPA7NGCZUKLACPWU3BORRGQUWTKSZNZDICEGZS6IXTRMINOIQ/representations/TIFF/versions/27ae2a60-3ebf-11e6-b03d-fa163e8d4ae3/files

 

As you can see the specified filename is abc. Now we can use it to access this file in Europeana Cloud via friendly URL.

 

Note

Just remember that a file will not be accessible until you make its representation persistent.


Code Block
 curl -X GET -H "Accept: application/json" --user user:password -i https://cloudecloud.europeanapsnc.eupl/api/data-providers/PSNC/records/exampleLocalRecord/representations/TIFF/abc

 

Filename used instead of a generated one can be also much more complex. It can for example contain / characters like in the absolute path. We can take a look at the real example provided by Europeana Newspapers.

Code Block
https://cloudecloud.europeanapsnc.eupl/api/data-providers/TheEuropeanLibrary/records/3000100349685/representations/presentation_images/node-2/image/NLE/???????????_??????????_?????????_=_Livländische_Gouvernements-Zeitung/1862/01/03/18620103_1-0001.jp2

 

As you can see the filename used here (node-2/image/NLE/???????????_??????????_?????????_=_Livländische_Gouvernements-Zeitung/1862/01/03/18620103_1-0001.jp2) is not only long with , having / characters inside but also contains unicode characters. We can also extract other well known values from this URL: data provider - TheEuropeanLibrary, local record identifier - 3000100349685, representation name - presentation_images.

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