No mapping was found for grel:date_toDate

[andrecastro0o]

Hi, I am playing a bit with RMLmapper and Yarrrml and tried to convert a date string to a xsd:datetime using grel:date_toDate function. However when I run the following error is returned

09:36:54.593 [main] ERROR be.ugent.rml.cli.Main .main(338) - No mapping was found for the function with IRI http://users.ugent.be/~bjdmeest/function/grel.ttl#date_toDate in the function descriptions.

I am using

• rmlio/rmlmapper-java:latest and rmlio/yarrrml-parser:latest (1.3.0) docker images
• The input file: episodes.json
• and the following mapping input

  
  prefixes:
  ex: http://www.example.com/
  grel: http://users.ugent.be/~bjdmeest/function/grel.ttl# 
  schema: http://schema.org/
  xsd: http://www.w3.org/2001/XMLSchema/

mappings: episode: sources:

• [episodes.json~jsonpath, "$.episodes[*]"] s: ex:episode_$(number) po:
• [a, schema:Episode]
• p: schema:name o: value: $(title) language: en
• p: schema:datePublished o: function: grel:date_toDate parameters:
  • [grel:valueParameter, $(airdate)]
  • [grel:param_string_pattern, "dd/MM/yyyy"]

Despite grel:date_toDate being in https://github.com/RMLio/rmlmapper-java/blob/d0abf65fa64dbb5dd654eae1748ec28def09b89a/src/main/resources/functions_grel.ttl#L1091

[DylanVanAssche]

Hi @andrecastro0o ! It seems that the Docker images are out of date on Docker Hub. We will update them soon so this should work then.

[DylanVanAssche]

@andrecastro0o Docker images are updated in Docker Hub, could you please try again? We're working on getting a system in place that outdated Docker images won't happen in the future :)

[andrecastro0o]

@DylanVanAssche, unfortunately the result is the same with the rmlio/rmlmapper-java image uploaded today.

rmlio/rmlmapper-java latest a6a05000dcf0 10 hours ago 725MB

rmlio/rmlmapper-java@sha256:d352e40d7048bb0bec3b3f9dcb51c9b03891c8625b8981adf9971a1e17796834

[DylanVanAssche]

@andrecastro0o I can reproduce it as well without Docker. Once we know a solution we will come back to you.

[thabils]

@andrecastro0o this seems to be a combination of 2 things: 1: There seems to be a bug in the grel:date_toDate function, I made a pull request that should fix this. 2: param_string_pattern should be p_string_pattern, otherwise it doesn't match with the function parameters of grel:data_toDate

[bblfish]

I came across the same problem. It helps to use the -v flag when debugging usingse rmlmapper. Also Functions should I think use blank nodes for the input attributes and outputs, as otherwise it leads to duplicate very similar looking names for the attributes parameter objects and the attribute parameter predicates that users should be using.

[bblfish]

@andrecastro0o this seems to be a combination of 2 things: 1: There seems to be a bug in the grel:date_toDate function, I made a pull request that should fix this.

What was the pull request? I could not find any link to it in this repo, so I am not sure if your bug fix works for the master branch here.

[namedgraph]

2: param_string_pattern should be p_string_pattern, otherwise it doesn't match with the function parameters of grel:data_toDate

@thabils how are we supposed to know this? The documentation states p_string_pattern yet the function is defined using param_string_pattern?

Any ETA for the fix of this bug?

[DylanVanAssche]

This was fixed in the docs! Use p_string_pattern. Thanks!