In fixity check REST API:

* Format fixity response as JSON
* Indicate success or failure in response body rather than in status
  code

lakesuperior/endpoints/admin.py

@@ -1,6 +1,6 @@
 import logging
 
-from flask import Blueprint, render_template
+from flask import Blueprint, jsonify, render_template
 
 from lakesuperior.api import admin as admin_api
 from lakesuperior.exceptions import (
@@ -59,13 +59,24 @@ def fixity_check(uid):
     Check the fixity of a resource.
     """
     uid = '/' + uid.strip('/')
+
     try:
         admin_api.fixity_check(uid)
     except ResourceNotExistsError as e:
         return str(e), 404
     except TombstoneError as e:
         return str(e), 410
     except ChecksumValidationError as e:
-        return str(e), 412
-
-    return f'Checksum for {uid} passed.', 200
+        check_pass = False
+    else:
+        check_pass = True
+
+
+    return (
+        jsonify({
+            'uid': uid,
+            'pass': check_pass,
+        }),
+        200,
+        {'content-type': 'application/json'}
+    )

tests/2_endpoints/test_admin.py

@@ -25,7 +25,11 @@ def test_fixity_check_ok(self):
         self.client.put(
             path, data=content, headers={'content-type': 'text/plain'})
 
-        assert self.client.get(fix_path).status_code == 200
+        rsp = self.client.get(fix_path)
+
+        assert rsp.status_code == 200
+        assert rsp.json['uid'] == f'/{uid}'
+        assert rsp.json['pass'] == True
 
 
     def test_fixity_check_corrupt(self):
@@ -45,7 +49,11 @@ def test_fixity_check_corrupt(self):
         with open(rsrc.local_path, 'wb') as fh:
             fh.write(uuid4().bytes)
 
-        assert self.client.get(fix_path).status_code == 412
+        rsp = self.client.get(fix_path)
+
+        assert rsp.status_code == 200
+        assert rsp.json['uid'] == f'/{uid}'
+        assert rsp.json['pass'] == False
 
 
     def test_fixity_check_missing(self):