requirements ESadapter for ES7

[guenterh]

using ES7 as the source for linked data requires an update of the php ES client (in general) and in conjunction of the php version

Our current vufind release defines a fix php version in composer.json (7.0.8) which is not sufficient for the new ES7 client which at least requires php 7.1 With our migration to ubuntu 18.04 we will run php 7.2 on the servers, so in general we should be able to change the php version in composer.json (as I have already done it with in the new branch https://github.com/swissbib/vufind/blob/migration_linked_es7/composer.json#L13)

Questions: a) Do we want to upgrade the minimal php version in composer.json? possible disadvantages:

• merge conflicts with vufind core
• runtime problems? (although we we would get them anyway because we are using php 7.2 on the new target hosts) b) Did I forget something? c) Do we use php 7.1 or php 7.2 in the composer.json definition? With 7.2 I could use the latest php ES7 client for at least version ES 7.3 (actually we are running 7.1.1 on our cluster but I guess we are going to update it in the near future)

[guenterh]

closed - we are going to use the latest PHP version I was wrong with my claim that latest ES7 client (7.3) requires 7.2 in fact it's 7.1 (https://packagist.org/packages/elasticsearch/elasticsearch#v7.3.0) So with VuFind 6 it shouldn't be necessary to modify the vufind composer.json file only for this aspect @liowalter fyi