Filtering the diff
All the filters listed in Filters can be applied to the differ’s output (“diff”) before it’s sent (see below how). In addition to these, two filters are custom-made for the default differ unified:
Standard filters
See here for the full list of generic filters. Below is an example on how you apply a generic filter to the result from the diff:
url: https://example.com
diff_filter:
- delete_lines_containing: "@@"
additions_only
Added in version 3.0.
The additions_only: true directive causes the report for that source to contain only lines that are added by the
unified diff (no deletions). This is extremely useful for monitoring new content on sites where content gets added at
the top and old content “scrolls” away.
Because lines that are modified generate both a deleted and an added line by the diff, this filter always displays modified lines.
As a safeguard, additions_only: true will display a warning when the size of the source shrinks by 75% or more,
as this could be due to changes in where or how the information is published (requiring the job to be reconfigured to
continue monitoring the relevant information), as well as all lines deleted.
Changes consisting exclusively of added empty lines are not reported.
Example:
url: https://example.com/#add_only
additions_only: true
Output:
or (text):
---------------------------------------------------------------------------
CHANGED: https://example.com/#add_only
---------------------------------------------------------------------------
... @ Sat, 12 Jul 2020 00:00:00 +0000
+++ @ Sat, 12 Jul 2020 01:00:00 +0000
/**Comparison type: Additions only**
@@ -1,2 +1,2 @@
+This is a line that has been added or changed
Example (when the source content shrinks by 75% or more):
url: https://example.com/#add_only2
additions_only: true
Output:
or (text):
---------------------------------------------------------------------------
CHANGED: https://example.com/#add_only2
---------------------------------------------------------------------------
--- @ Sat, 12 Jul 2020 00:00:00 +0000
+++ @ Sat, 12 Jul 2020 01:00:00 +0000
/**Comparison type: Additions only**
/**Deletions are being shown as 75% or more of the content has been deleted**
@@ -1,3 +0,0 @@
-# Example Domain
-This domain is for use in illustrative examples in documents. You may use this domain in literature without prior coordination or asking for permission.
-[More information...](https://www.iana.org/domains/example)
---------------------------------------------------------------------------
Note: When using additions_only: true, the differ directive context_lines (the number of
context lines) is set to 0 instead of the default 3; of course, this can be overriden by specifying the directive with
the desired value in the differ directive.
Changed in version 3.5: Additions consisting of only empty lines are not reported.
deletions_only
Added in version 3.0.
The deletions_only: true directive causes a unified diff to contain only lines that are deleted by the diff (no
additions).
Changes consisting exclusively of deleted empty lines are not reported.
Example:
url: https://example.com/#del_only
deletions_only: true
Output:
or (text):
---------------------------------------------------------------------------
CHANGED: https://example.com/#del_only
---------------------------------------------------------------------------
--- @ Sat, 12 Jul 2020 00:00:00 +0000
... @ Sat, 12 Jul 2020 01:00:00 +0000
/**Comparison type: Deletions only**
@@ -1,2 +1,2 @@
-This is a line that has been deleted or changed
Note: When using deletions_only: true, the differ directive context_lines (the number of
context lines) is set to 0 instead of the default 3; of course, this can be overriden by specifying the directive with
the desired value in the differ directive.
Changed in version 3.5: Deletions consisting of only empty lines are not reported.