the post_excerpt is not part of the index

The excerpt will not be added to the solr index, in that way you cannot search for any of its information.

The field post_excerpt could hold additional information to an post, that completely differs that in post_content.
So, in my understanding, to get a accurate search result for posts, the excerpt should be added.

All details of the changes i had to made to add the excerpt to the solr index are in this SVN diff.

Index: solr/wpsolr-index-solr-client.php
===================================================================
— solr/wpsolr-index-solr-client.php (revision 2562)
+++ solr/wpsolr-index-solr-client.php (working copy)
@@ -484,6 +484,7 @@
// Post is NOT an attachment: we get the document body from the post object
$pcontent = $post_to_index->post_content;
}
+ $pexcerpt = $post_to_index->post_excerpt;
$pauth_info = get_userdata( $post_to_index->post_author );
$pauthor = isset( $pauth_info ) ? $pauth_info->display_name : ”;
$pauthor_s = isset( $pauth_info ) ? get_author_posts_url( $pauth_info->ID, $pauth_info->user_nicename
) : ”;
@@ -575,6 +576,8 @@

// Remove HTML tags
$solarium_document_for_update[ WpSolrSchema::_FIELD_NAME_CONTENT ] = strip_tags( $content_with_shortcodes_expanded_or_stripped
);
+
+ $solarium_document_for_update[ WpSolrSchema::_FIELD_NAME_EXCERPT ] = $pexcerpt;

$solarium_document_for_update[ WpSolrSchema::_FIELD_NAME_AUTHOR ] = $pauthor;
$solarium_document_for_update[ WpSolrSchema::_FIELD_NAME_AUTHOR_S ] = $pauthor_s;

Index: wpsolr-schema.php
===================================================================
— wpsolr-schema.php (revision 2562)
+++ wpsolr-schema.php (working copy)
@@ -15,6 +15,7 @@
const _FIELD_NAME_PID = ‘PID’;
const _FIELD_NAME_TITLE = ‘title’;
const _FIELD_NAME_CONTENT = ‘content’;
+ const _FIELD_NAME_EXCERPT = ‘excerpt’;
const _FIELD_NAME_AUTHOR = ‘author’;
const _FIELD_NAME_AUTHOR_S = ‘author_s’;
const _FIELD_NAME_TYPE = ‘type’;

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