From 89e1cabc58fdde98b30cae4aebf363667efd762e Mon Sep 17 00:00:00 2001
From: sourcepirate <E0267819@u.nus.edu>
Date: Sat, 5 Sep 2020 23:51:54 +0800
Subject: [PATCH] support for offset to do record pagination

---
 Cargo.toml      | 2 +-
 src/searcher.rs | 7 ++++---
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index a9179b2..44f7e17 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -13,7 +13,7 @@ crate-type = ["cdylib"]
 
 [dependencies]
 chrono = "0.4.11"
-tantivy = "0.12.0"
+tantivy = "0.13.0"
 itertools = "0.9.0"
 futures = "0.3.4"
 
diff --git a/src/searcher.rs b/src/searcher.rs
index f2ba1d3..6ea2952 100644
--- a/src/searcher.rs
+++ b/src/searcher.rs
@@ -98,12 +98,13 @@ impl Searcher {
     /// Returns `SearchResult` object.
     ///
     /// Raises a ValueError if there was an error with the search.
-    #[args(limit = 10, count = true)]
+    #[args(limit = 10, offset = 0, count = true)]
     fn search(
         &self,
         _py: Python,
         query: &Query,
         limit: usize,
+        offset: usize, 
         count: bool,
         order_by_field: Option<&str>,
     ) -> PyResult<SearchResult> {
@@ -119,7 +120,7 @@ impl Searcher {
             if let Some(order_by) = order_by_field {
                 let field = get_field(&self.inner.index().schema(), order_by)?;
                 let collector =
-                    TopDocs::with_limit(limit).order_by_u64_field(field);
+                    TopDocs::with_limit(limit).and_offset(offset).order_by_u64_field(field);
                 let top_docs_handle = multicollector.add_collector(collector);
                 let ret = self.inner.search(&query.inner, &multicollector);
 
@@ -137,7 +138,7 @@ impl Searcher {
                     Err(e) => return Err(ValueError::py_err(e.to_string())),
                 }
             } else {
-                let collector = TopDocs::with_limit(limit);
+                let collector = TopDocs::with_limit(limit).and_offset(offset);
                 let top_docs_handle = multicollector.add_collector(collector);
                 let ret = self.inner.search(&query.inner, &multicollector);