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18

CKAN stands for Comprehensive Knowledge Archive Network. CKAN is a self-described data portal platform that allows an organization to manage, publish, and share data and for others to find and use that data. In general, data portal platforms provide a structured solution of software, policies, and guidelines that let an organization (often a government ...


13

Firstly, let me note that I work at Socrata with Ian. I agree that maintaining technical options and preventing lock-in is important but, I disagree that Socrata fosters lock-in of any kind. Lock-in, for open data, could come from two sources--the data and the API. Socrata enables customers and users to download the data via a huge number of open ...


10

With respect to the question about Socrata and CKAN complementing each other, I also work at Socrata and support a number of Federal agencies on data publishing efforts. I’m seeing more and more cases where Socrata and CKAN are both part of a federated ecosystem of data publishing activities rather than one monolithic catalog that must serve everyone. IMO we’...


10

I'm also quite biased because I work on CKAN and DKAN, but four things to add: 1) Both CKAN and Socrata are often integrated in various ways with a Content Management System such as Wordpress (data.gov) or Drupal (data.gov.uk), in order to more readily provide a more full featured web portal including use cases like telling stories around data, creating ...


10

Figuring out the cost for running CKAN boils down to two different categories: the cost of running the software itself, as well as the cost of building and maintaining your open data catalog going forward. The cost of the software itself is simpler to answer: CKAN itself is free/open-source, and available as a hosted solution. If you go the open-source ...


9

As you say, http://datahub.io is a particular instance powered by CKAN, so you can't really compare both. In terms of what is particular about datahub.io, it is a community centred and powered site where everybody should be able to host their data, rather than the more default scenario of one or more organizations publishing data on the portal. It is in the ...


8

You've asked three separate questions in one question, I don't think this fits into Stack Exchange's one question, one answer model, should have been three separate posts maybe. But anyway.. It appears that every API response includes a JSON piece with help information. can this be excluded? No :) Not as far as I know. Just ignore it. I agree it seems a ...


8

Just a quick response from CKAN -- Second, there are some basic differences about the tools. Socrata is a turn-key product solution; CKAN requires technically-savvy people to implement and maintain their project solution. One approach is not universally better than the other, they are just different. We (the OKF) also offer a hosted solution where all ...


7

For now the Data.gov CKAN API redirects package_list to package_search and for package_search the relevant Solr parameters to limit your query are rows and start. For example, http://catalog.data.gov/api/3/action/package_search?rows=1000&start=0 And then page through. If you or anyone has additional feedback on what Data.gov CKAN API documentation ...


7

Yes. CKAN is licensed under Affero GNU GPL v3.0. From the preamble to the license: When we speak of free software, we are referring to freedom, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for them if you wish), that you receive source code or can get it if you ...


6

To add to amercader's answer, if you have some data to publish and are wondering whether to use datahub.io or your own CKAN instance, there are various considerations. Using datahub.io is free and requires no setup, site hosting, etc. With your own instance, you can have a data portal 'homed' at your own web address (e.g. data.myorganisation.org). You can ...


6

CAVEAT: I am not an experienced user of the CKAN software. From reviewing the online documentation, it appears that CKAN supports storing data in two methods: FileStore and DataStore. FileStore is storing and retrieving an entire datasets (e.g., CSV file, PDF document, etc). It does not involve a database. The Datastore uses what they call an ad-hoc ...


5

There are a number of lenses through which a choice of platforms can be viewed. I will suggest one other ... from the perspective of risk management. CKAN, especially the option of taking the code base without OKF support, requires a user to essentially bear all risks associated with install, integration and platform service and updating on an ongoing ...


5

ckan.action will pass all the keywords parameters onto whatever API call you are using, so you can pass any parameter supported by package_search to it (I'll use PDF instead of WMS to get some results): import ckanclient q = 'tags:sea_water_temperature' ckan = ckanclient.CkanClient('http://catalog.data.gov/api/3') d = ckan.action('package_search', q=q, rows=...


5

The POST syntax is fine - you get the same results using the web front end: http://catalog.data.gov/dataset?q=sea_water_temperature&sort=score+desc%2C+name+asc&ext_location=&ext_bbox=&ext_prev_extent=-254.53125%2C-75.84516854027044%2C54.84375%2C83.19489563661588 However the underscores are being treated as spaces, so effectively your query ...


5

It has nothing to do with GET vs POST, you seem to be using two different API versions. In the first case you are using version 1 of the CKAN API (http://catalog.data.gov/api/search/dataset), which is deprecated. This version returns a list of dataset ids. In the second case you are using version 3 of the CKAN API (http://catalog.data.gov/api/3/action/...


5

This is not supported by the CKAN API, so you would need to script it.


5

There is a simple answer thanks to the isopen parameter. Here's the query: http://datahub.io/api/3/action/package_search?q=isopen:true Note that q is basically the classic solr query paramemter so if you want to combine this with normal queries you do stuff like: http://datahub.io/api/3/action/package_search?q=gold%20isopen:true Or, slightly more ...


4

I am going to admit some bias up-front by saying that I work for Socrata. But I'm also a believer in open source, so please afford me a chance to provide a thoughtful response with three points. First, I don't consider CKAN vs Socrata as an "either / or" decision. Sure, both the OKFN and Socrata have a similar vision for our customers. But looking at how ...


4

I think this is a very subjective question. What is a small government... a local government with a population of 10,000 or 100,000? How much traffic is there going to be? Are there people already familiar on the workings of CKAN, if not will training be paid for? Is CKAN going to be augmented into an already existing IT department (cheaper) or will a new ...


4

CKAN is an open-source software platform for publishing data. data.gov.uk is one of many examples where it's used to help implement 'open government data' programmes (in this case, from the UK government). It's also used to publish, e.g., scientific data. The first ever instance of CKAN was originally called 'The Comprehensive Knowledge Archive Network' and ...


4

Did you have a look at CKAN's extensive API documentation? To get you started, look at the answer to related question How do I get a full list of datasets available on Data.Gov using the CKAN API? and its example of using package_search. Once you have a list of dataset IDs, you can get their metadata using the package_show API function. The package url ...


4

There are some API limits tied to a specific API key. If a third-party used your key, their calls would effect how many calls you can make.


4

No, the only currently supported database backend is PostgreSQL. It was chosen as it is an open source, well supported and widely available solution. Support for other backends would need to be added to the core library as new feature (CKAN uses SQLAlchemy as ORM, which would help). If someone is up for it they can check the contributing docs and get in ...


3

Have you looked at https://github.com/ckan/ckanapi ? It is the official and current python client for CKAN.


3

The filters on the search page sidebar can be configured implementing the IFacets interface from your own extension (you'll need to write some code for that). For instance, these ones are defined like this: https://github.com/okfn/ckanext-tsbsatellites/blob/master/ckanext/tsbsatellites/plugin.py#L236:L249


3

It's kind of hacky, but you can use a search engine like Google to search within a domain, and then exclude certain strings that indicate the dataset has no data. LINK In this case, the search includes pages with: ESIS (but can be left blank) site:datahub.io/dataset/ (include the dataset folder because otherwise, the "no data" message comes in various ...


3

Revisioning in CKAN is something that needs to be refactored and that is currently not exposed via the UI but internally objects are being revisioned and assigned a revision_id, including resources, that is accessible via the API. See eg: http://demo.ckan.org/api/3/action/package_show?id=8beb8f98-3a71-4615-a38d-6155f4b9153a http://demo.ckan.org/api/3/...


3

AFAIK, at least one : should be used in order to enable advanced search on CKAN: https://catalog.data.gov/dataset?q=title:abracadabra+OR+crime+OR+court+OR+justice+OR+pretrial


2

I tell folks that it is the Drupal or Wordpress of data catalogs. Or an open source Socrata. (Disclaimer - I am the Sr. API Strategist for GSA)


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