NAME

Catmandu::Fix::lookup_in_store - change the value of a HASH key or ARRAY index by looking up its value in a store

SYNOPSIS

# Lookup in an SQLLite database
lookup_in_store(foo.bar, DBI, data_source: "dbi:SQLite:path/data.sqlite")

# Lookup in a MongoDB database
lookup_in_store(foo.bar, MongoDB, database_name: lookups, bag: mydata)

# Lookup in a MongoDB database, using the default bag and a default value when nothing found
lookup_in_store(foo.bar, MongoDB, database_name: lookups, default: 'default value')

# Lookup in a MongoDB database, using the default bag and delete the foo.bar field when nothing found
lookup_in_store(foo.bar, MongoDB, database_name: lookups, delete: 1)

# Or, a much faster option: use a named store in a catmandu.yml file
#
# store:
#  mydbi:
#    package: DBI
#    options:
#      data_source: "dbi:SQLite:path/data.sqlite"
#  mymongo:
#    package: MongoDB
#    options:
#      database_name: lookups
lookup_in_store(foo.bar, mydbi)
lookup_in_store(foo.bar, mymongo, bag: mydata)
lookup_in_store(foo.bar, mymongo, default: 'default value')
lookup_in_store(foo.bar, mymongo, delete: 1)

DESCRIPTION

lookup_in_store(PATH,STORE[,store_param: store_val, ...][,bag: bag_name][,delete:1][,default:value])

Use the lookup_in_store fix to match a field in a record to the "_id" field in a Catmandu::Store of choice. For instance, if a Catmandu::Store contains these records:

---
_id: water
fr: l'eau
de: wasser
en: water
nl: water
---
_id: tree
fr: arbre
de: baum
en: tree
nl: boom

And you data contains these fields:

---
_id: 001
tag: tree
---
_id: 002
tag: water

Then, the fix below will lookup a tag in the Catmandu::Store and replace it with the database value:

lookup_in_store(tag, DBI, data_source: "dbi:SQLite:path/data.sqlite")

The resulting data will contain:

---
_id: 001
tag:
  _id: tree
  fr: arbre
  de: baum
  en: tree
  nl: boom
---
_id: 002
tag:
  _id: water
  fr: l'eau
  de: wasser
  en: water
  nl: water

DATABASE CONNECTIONS

For every call to a lookup_in_store a new database connection is created. It is much more effient to used named stores in a catmandu.yml file. This file needs to contain all the connection parameters to the database. E.g.

store:
   mystore:
     package: MongoDB
     options:
        database_name: mydata

The catmandu.yml file should be available in the same directory as where the catmandu command is executed. Or, this directory can be set with the -L option:

$ catmandu -L /tmp/path convert ...

SEE ALSO

Catmandu::Fix, Catmandu::Store , Catmandu::Fix::add_to_store