Update backend READMEs, rename some files for consistency

1 files changed, 43 insertions, 30 deletions

diff --git a/backend/data/enwiki/README.md b/backend/data/enwiki/README.md
index 6462d7d..1c16a2e 100644
--- a/backend/data/enwiki/README.md
+++ b/backend/data/enwiki/README.md
@@ -1,39 +1,52 @@
-Downloaded Files
-================
+This directory holds files obtained from/using [English Wikipedia](https://en.wikipedia.org/wiki/Main_Page).
+
+# Downloaded Files
 -   enwiki-20220501-pages-articles-multistream.xml.bz2 <br>
-    Obtained via <https://dumps.wikimedia.org/backup-index.html>
-    (site suggests downloading from a mirror).  Contains text
-    content and metadata for pages in English Wikipedia
-    (current revision only, excludes talk pages).  Some file
-    content and format information was available from
-    <https://meta.wikimedia.org/wiki/Data_dumps/What%27s_available_for_download>.
+    Obtained via <https://dumps.wikimedia.org/backup-index.html> (site suggests downloading from a mirror).
+    Contains text content and metadata for pages in enwiki.
+    Some file content and format information was available from
+        <https://meta.wikimedia.org/wiki/Data_dumps/What%27s_available_for_download>.
 -   enwiki-20220501-pages-articles-multistream-index.txt.bz2 <br>
     Obtained like above. Holds lines of the form offset1:pageId1:title1,
-    providing offsets, for each page, into the dump file, of a chunk of
+    providing, for each page, an offset into the dump file of a chunk of
     100 pages that includes it.
 
-Generated Files
-===============
+# Generated Dump-Index Files
+-   genDumpIndexDb.py <br>
+    Creates an sqlite-database version of the enwiki-dump index file.
 -   dumpIndex.db <br>
-    Holds data from the enwiki dump index file. Generated by
-    genDumpIndexDb.py, and used by lookupPage.py to get content for a
-    given page title. <br>
+    Generated by genDumpIndexDb.py. <br>
     Tables: <br>
-    -   offsets: title TEXT PRIMARY KEY, id INT UNIQUE, offset INT, next\_offset INT
--   enwikiData.db <br>
-    Holds data obtained from the enwiki dump file, in 'pages',
-    'redirects', and 'descs' tables. Generated by genData.py, which uses
-    python packages mwxml and mwparserfromhell. <br>
+    -   `offsets`: `title TEXT PRIMARY KEY, id INT UNIQUE, offset INT, next_offset INT`
+
+# Description Database Files
+-   genDescData.py <br>
+    Reads through pages in the dump file, and adds short-description info to a database.
+-   descData.db <br>
+    Generated by genDescData.py. <br>
     Tables: <br>
-    -   pages:     id INT PRIMARY KEY, title TEXT UNIQUE
-    -   redirects: id INT PRIMARY KEY, target TEXT
-    -   descs:     id INT PRIMARY KEY, desc TEXT
--   enwikiImgs.db <br>
-    Holds infobox-images obtained for some set of wiki page-ids.
-    Generated by running getEnwikiImgData.py, which uses the enwiki dump
-    file and dumpIndex.db. <br>
+    -   `pages`:     `id INT PRIMARY KEY, title TEXT UNIQUE`
+    -   `redirects`: `id INT PRIMARY KEY, target TEXT`
+    -   `descs`:     `id INT PRIMARY KEY, desc TEXT`
+
+# Image Database Files
+-   genImgData.py <br>
+    Used to find infobox image names for page IDs, storing them into a database.
+-   downloadImgLicenseInfo.py <br>
+    Used to download licensing metadata for image names, via wikipedia's online API, storing them into a database.
+-   imgData.db <br>
+    Used to hold metadata about infobox images for a set of pageIDs.
+    Generated using getEnwikiImgData.py and downloadImgLicenseInfo.py. <br>
     Tables: <br>
-    -   page\_imgs: page\_id INT PRIMAY KEY, img\_name TEXT
-        (img\_name may be null, which is used to avoid re-processing the page-id on a second pass)
-    -   imgs: name TEXT PRIMARY KEY, license TEXT, artist TEXT, credit TEXT, restrictions TEXT, url TEXT
-        (might lack some matches for 'img_name' in 'page_imgs', due to inability to get license info)
+    -   `page_imgs`: `page_id INT PRIMAY KEY, img_name TEXT` <br>
+        `img_name` may be null, which means 'none found', and is used to avoid re-processing page-ids.
+    -   `imgs`: `name TEXT PRIMARY KEY, license TEXT, artist TEXT, credit TEXT, restrictions TEXT, url TEXT` <br>
+        Might lack some matches for `img_name` in `page_imgs`, due to licensing info unavailability.
+-   downloadEnwikiImgs.py <br>
+    Used to download image files into imgs/.
+
+# Other Files
+-   lookupPage.py <br>
+    Running `lookupPage.py title1` looks in the dump for a page with a given title,
+    and prints the contents to stdout. Uses dumpIndex.db.
+