Bug 38931: Add endpoints for individual credits and debits

As the title says, we are missing such endpoints and this patch adds
them.

To test:
1. Apply this patches
2. Run:
   $ ktd --shell
  k$ yarn api:bundle
  k$ prove t/db_dependent/api/v1/patrons_accounts.t
=> SUCCESS: The spec builds!
=> SUCCESS: The tests pass!
3. Verify all the codepaths are covered by tests
4. Sign off :-D

Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Martin Renvoize <martin.renvoize@openfifth.co.uk>
Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>

Koha/REST/V1/Patrons/Account.pm

@@ -174,6 +174,30 @@ sub add_credit {
     };
 }
 
+=head3 get_credit
+
+=cut
+
+sub get_credit {
+    my $c = shift->openapi->valid_input or return;
+
+    my $patron = Koha::Patrons->find( $c->param('patron_id') );
+
+    return $c->render_resource_not_found("Patron")
+        unless $patron;
+
+    return try {
+        my $credit = $c->objects->find( $patron->account->credits, $c->param('credit_id') );
+
+        return $c->render_resource_not_found("Credit")
+            unless $credit;
+
+        return $c->render( status => 200, openapi => $credit );
+    } catch {
+        $c->unhandled_exception($_);
+    };
+}
+
 =head3 list_debits
 
 =cut
@@ -194,6 +218,30 @@ sub list_debits {
     };
 }
 
+=head3 get_debit
+
+=cut
+
+sub get_debit {
+    my $c = shift->openapi->valid_input or return;
+
+    my $patron = Koha::Patrons->find( $c->param('patron_id') );
+
+    return $c->render_resource_not_found("Patron")
+        unless $patron;
+
+    return try {
+        my $debit = $c->objects->find( $patron->account->debits, $c->param('debit_id') );
+
+        return $c->render_resource_not_found("Debit")
+            unless $debit;
+
+        return $c->render( status => 200, openapi => $debit );
+    } catch {
+        $c->unhandled_exception($_);
+    };
+}
+
 =head3 add_debit
 
 =cut

api/v1/swagger/paths/patrons_account.yaml

@@ -144,6 +144,47 @@
     x-koha-authorization:
       permissions:
         updatecharges: remaining_permissions
+"/patrons/{patron_id}/account/credits/{credit_id}":
+  get:
+    x-mojo-to: Patrons::Account#get_credit
+    operationId: getPatronCredit
+    tags:
+      - patrons
+    summary: Get a patron credit
+    produces:
+      - application/json
+    parameters:
+      - $ref: "../swagger.yaml#/parameters/patron_id_pp"
+      - $ref: "../swagger.yaml#/parameters/credit_id_pp"
+    responses:
+      "200":
+        description: A patron credit
+        schema:
+          $ref: "../swagger.yaml#/definitions/credit"
+      "400":
+        description: Bad request
+        schema:
+          $ref: "../swagger.yaml#/definitions/error"
+      "403":
+        description: Access forbidden
+        schema:
+          $ref: "../swagger.yaml#/definitions/error"
+      "404":
+        description: Patron not found
+        schema:
+          $ref: "../swagger.yaml#/definitions/error"
+      "500":
+        description: Internal error
+        schema:
+          $ref: "../swagger.yaml#/definitions/error"
+      "503":
+        description: Under maintenance
+        schema:
+          $ref: "../swagger.yaml#/definitions/error"
+    x-koha-authorization:
+      permissions:
+        borrowers: edit_borrowers
+        updatecharges: remaining_permissions
 "/patrons/{patron_id}/account/debits":
   get:
     x-mojo-to: Patrons::Account#list_debits
@@ -246,3 +287,44 @@
     x-koha-authorization:
       permissions:
         updatecharges: remaining_permissions
+"/patrons/{patron_id}/account/debits/{debit_id}":
+  get:
+    x-mojo-to: Patrons::Account#get_debit
+    operationId: getPatronDebit
+    tags:
+      - patrons
+    summary: Get a patron debit
+    produces:
+      - application/json
+    parameters:
+      - $ref: "../swagger.yaml#/parameters/patron_id_pp"
+      - $ref: "../swagger.yaml#/parameters/debit_id_pp"
+    responses:
+      "200":
+        description: A patron debit
+        schema:
+          $ref: "../swagger.yaml#/definitions/debit"
+      "400":
+        description: Bad request
+        schema:
+          $ref: "../swagger.yaml#/definitions/error"
+      "403":
+        description: Access forbidden
+        schema:
+          $ref: "../swagger.yaml#/definitions/error"
+      "404":
+        description: Patron not found
+        schema:
+          $ref: "../swagger.yaml#/definitions/error"
+      "500":
+        description: Internal error
+        schema:
+          $ref: "../swagger.yaml#/definitions/error"
+      "503":
+        description: Under maintenance
+        schema:
+          $ref: "../swagger.yaml#/definitions/error"
+    x-koha-authorization:
+      permissions:
+        borrowers: edit_borrowers
+        updatecharges: remaining_permissions

api/v1/swagger/swagger.yaml

@@ -483,6 +483,10 @@ paths:
     $ref: "./paths/patrons_account.yaml#/~1patrons~1{patron_id}~1account"
   "/patrons/{patron_id}/account/credits":
     $ref: "./paths/patrons_account.yaml#/~1patrons~1{patron_id}~1account~1credits"
+  "/patrons/{patron_id}/account/credits/{credit_id}":
+      $ref: "./paths/patrons_account.yaml#/~1patrons~1{patron_id}~1account~1credits~1{credit_id}"
+  "/patrons/{patron_id}/account/debits/{debit_id}":
+      $ref: "./paths/patrons_account.yaml#/~1patrons~1{patron_id}~1account~1debits~1{debit_id}"
   "/patrons/{patron_id}/account/debits":
     $ref: "./paths/patrons_account.yaml#/~1patrons~1{patron_id}~1account~1debits"
   "/patrons/{patron_id}/extended_attributes":
@@ -719,6 +723,18 @@ parameters:
     name: club_id
     required: true
     type: integer
+  credit_id_pp:
+    description: Internal credit identifier
+    in: path
+    name: credit_id
+    required: true
+    type: integer
+  debit_id_pp:
+    description: Internal debit identifier
+    in: path
+    name: debit_id
+    required: true
+    type: integer
   eholdings_title_id_pp:
     description: Title internal identifier
     in: path