Modified Tag Pagination to get all query parameters from Link Header.

This ensures that this library will work with registries that do not
use a "next_page" query parameter as next_page seems to be non-standard
and does not align with the dockerv2 api spec as defined:
https://docs.docker.com/registry/spec/api/#pagination-1

Author: kobutton

src/v2/tags.rs

@@ -50,8 +50,8 @@ impl Client {
     ) -> Result<(TagsChunk, Option<String>)> {
         let url_paginated = match (paginate, link) {
             (Some(p), None) => format!("{}?n={}", base_url, p),
-            (None, Some(l)) => format!("{}?next_page={}", base_url, l),
-            (Some(p), Some(l)) => format!("{}?n={}&next_page={}", base_url, p, l),
+            (None, Some(l)) => format!("{}?{}", base_url, l),
+            (Some(_p), Some(l)) => format!("{}?{}", base_url, l),
             _ => base_url.to_string(),
         };
         let url = Url::parse(&url_paginated)?;
@@ -108,16 +108,9 @@ fn parse_link(hdr: Option<&header::HeaderValue>) -> Option<String> {
 
     // Query parameters for next page URL.
     let uri = sval.trim_end_matches(">; rel=\"next\"");
-    let query: Vec<&str> = uri.splitn(2, "next_page=").collect();
-    let params = match query.get(1) {
-        Some(v) if !v.is_empty() => v,
-        _ => return None,
-    };
-
-    // Last item in current page (pagination parameter).
-    let last: Vec<&str> = params.splitn(2, '&').collect();
-    match last.first().cloned() {
-        Some(v) if !v.is_empty() => Some(v.to_string()),
+    let query: Vec<&str> = uri.splitn(2, "?").collect();
+    match query.get(1) {  //use the entire query param string since some registries have different ways of pagination
+        Some(v) if !v.is_empty() => Some(v.to_string()), 
         _ => None,
     }
 }

tests/mock/mod.rs

@@ -2,4 +2,5 @@ mod api_version;
 mod base_client;
 mod blobs_download;
 mod catalog;
-mod tags;
+mod tags_dockerv2;
+mod tags_quay;

tests/mock/tags_dockerv2.rs

@@ -0,0 +1,147 @@
+extern crate dkregistry;
+extern crate futures;
+extern crate mockito;
+extern crate tokio;
+
+use self::futures::StreamExt;
+use self::mockito::mock;
+use self::tokio::runtime::Runtime;
+
+#[test]
+fn test_dockerv2_tags_simple() {
+    let name = "repo";
+    let tags = r#"{"name": "repo", "tags": [ "t1", "t2" ]}"#;
+
+    let ep = format!("/v2/{}/tags/list", name);
+    let addr = mockito::server_address().to_string();
+    let _m = mock("GET", ep.as_str())
+        .with_status(200)
+        .with_header("Content-Type", "application/json")
+        .with_body(tags)
+        .create();
+
+    let runtime = Runtime::new().unwrap();
+    let dclient = dkregistry::v2::Client::configure()
+        .registry(&addr)
+        .insecure_registry(true)
+        .username(None)
+        .password(None)
+        .build()
+        .unwrap();
+
+    let futcheck = dclient.get_tags(name, None);
+
+    let res = runtime.block_on(futcheck.map(Result::unwrap).collect::<Vec<_>>());
+    assert_eq!(res.get(0).unwrap(), &String::from("t1"));
+    assert_eq!(res.get(1).unwrap(), &String::from("t2"));
+
+    mockito::reset();
+}
+
+#[test]
+fn test_dockerv2_tags_paginate() {
+    let name = "repo";
+    let tags_p1 = r#"{"name": "repo", "tags": [ "t1" ]}"#;
+    let tags_p2 = r#"{"name": "repo", "tags": [ "t2" ]}"#;
+
+    let ep1 = format!("/v2/{}/tags/list?n=1", name);
+    let ep2 = format!("/v2/{}/tags/list?n=1&last=t1", name);
+    let addr = mockito::server_address().to_string();
+    let _m1 = mock("GET", ep1.as_str())
+        .with_status(200)
+        .with_header(
+            "Link",
+            &format!(
+                r#"<{}/v2/_tags?n=1&last=t1>; rel="next""#,
+                mockito::server_url()
+            ),
+        )
+        .with_header("Content-Type", "application/json")
+        .with_body(tags_p1)
+        .create();
+    let _m2 = mock("GET", ep2.as_str())
+        .with_status(200)
+        .with_header("Content-Type", "application/json")
+        .with_body(tags_p2)
+        .create();
+
+    let runtime = Runtime::new().unwrap();
+    let dclient = dkregistry::v2::Client::configure()
+        .registry(&addr)
+        .insecure_registry(true)
+        .username(None)
+        .password(None)
+        .build()
+        .unwrap();
+
+    let next = Box::pin(dclient.get_tags(name, Some(1)).map(Result::unwrap));
+
+    let (first_tag, stream_rest) = runtime.block_on(next.into_future());
+    assert_eq!(first_tag.unwrap(), "t1".to_owned());
+
+    let (second_tag, stream_rest) = runtime.block_on(stream_rest.into_future());
+    assert_eq!(second_tag.unwrap(), "t2".to_owned());
+
+    let (end, _) = runtime.block_on(stream_rest.into_future());
+    if end.is_some() {
+        panic!("end is some: {:?}", end);
+    }
+
+    mockito::reset();
+}
+
+#[test]
+fn test_dockerv2_tags_404() {
+    let name = "repo";
+    let ep = format!("/v2/{}/tags/list", name);
+    let addr = mockito::server_address().to_string();
+    let _m = mock("GET", ep.as_str())
+        .with_status(404)
+        .with_header("Content-Type", "application/json")
+        .create();
+
+    let runtime = Runtime::new().unwrap();
+    let dclient = dkregistry::v2::Client::configure()
+        .registry(&addr)
+        .insecure_registry(true)
+        .username(None)
+        .password(None)
+        .build()
+        .unwrap();
+
+    let futcheck = dclient.get_tags(name, None);
+
+    let res = runtime.block_on(futcheck.collect::<Vec<_>>());
+    assert!(res.get(0).unwrap().is_err());
+
+    mockito::reset();
+}
+
+#[test]
+fn test_dockerv2_tags_missing_header() {
+    let name = "repo";
+    let tags = r#"{"name": "repo", "tags": [ "t1", "t2" ]}"#;
+    let ep = format!("/v2/{}/tags/list", name);
+
+    let addr = mockito::server_address().to_string();
+    let _m = mock("GET", ep.as_str())
+        .with_status(200)
+        .with_body(tags)
+        .create();
+
+    let runtime = Runtime::new().unwrap();
+    let dclient = dkregistry::v2::Client::configure()
+        .registry(&addr)
+        .insecure_registry(true)
+        .username(None)
+        .password(None)
+        .build()
+        .unwrap();
+
+    let futcheck = dclient.get_tags(name, None);
+
+    let res = runtime.block_on(futcheck.map(Result::unwrap).collect::<Vec<_>>());
+    assert_eq!(vec!["t1", "t2"], res);
+
+    mockito::reset();
+}

tests/mock/tags.rs renamed to tests/mock/tags_quay.rs

@@ -8,7 +8,7 @@ use self::mockito::mock;
 use self::tokio::runtime::Runtime;
 
 #[test]
-fn test_tags_simple() {
+fn test_quay_tags_simple() {
     let name = "repo";
     let tags = r#"{"name": "repo", "tags": [ "t1", "t2" ]}"#;
 
@@ -39,7 +39,7 @@ fn test_tags_simple() {
 }
 
 #[test]
-fn test_tags_paginate() {
+fn test_quay_tags_paginate() {
     let name = "repo";
     let tags_p1 = r#"{"name": "repo", "tags": [ "t1" ]}"#;
     let tags_p2 = r#"{"name": "repo", "tags": [ "t2" ]}"#;
@@ -91,7 +91,7 @@ fn test_tags_paginate() {
 }
 
 #[test]
-fn test_tags_404() {
+fn test_quay_tags_404() {
     let name = "repo";
     let ep = format!("/v2/{}/tags/list", name);
     let addr = mockito::server_address().to_string();
@@ -118,7 +118,7 @@ fn test_tags_404() {
 }
 
 #[test]
-fn test_tags_missing_header() {
+fn test_quay_tags_missing_header() {
     let name = "repo";
     let tags = r#"{"name": "repo", "tags": [ "t1", "t2" ]}"#;
     let ep = format!("/v2/{}/tags/list", name);