promisor-remote: keep advertised filters in memory

Currently, advertised filters are only kept in memory temporarily
during parsing, or persisted to disk if `promisor.storeFields`
contains 'partialCloneFilter'.

In a following commit though, we will add a `--filter=auto` option.
This option will enable the client to use the filters that the server
is suggesting for the promisor remotes the client accepts.

To use them even if `promisor.storeFields` is not configured, these
filters should be stored somewhere for the current session.

Let's add an `advertised_filter` field to `struct promisor_remote`
for that purpose.

To ensure that the filters are available in all cases,
filter_promisor_remote() captures them into a temporary list and
applies them to the `promisor_remote` structs after the potential
configuration reload.

Then the accepted remotes are marked as `accepted` in the repository
state. This ensures that subsequent calls to look up accepted remotes
(like in the filter construction below) actually find them.

In a following commit, we will add a `--filter=auto` option that will
enable a client to use the filters suggested by the server for the
promisor remotes the client accepted.

To enable the client to construct a filter spec based on these filters,
let's also add a `promisor_remote_construct_filter(repo)` function.

This function:

- iterates over all accepted promisor remotes in the repository,
- collects the filters advertised for them (using `advertised_filter`
  added in this commit, and
- generates a single filter spec for them.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/promisor-remote.c b/promisor-remote.c
index 59997dd4c78812aaa6a0c630095f2a04e2002016..f3bafb7731c9628d57af497883cac06f4becd53e 100644 (file)
--- a/promisor-remote.c
+++ b/promisor-remote.c
@@ -193,6 +193,7 @@ void promisor_remote_clear(struct promisor_remote_config *config)
        while (config->promisors) {
                struct promisor_remote *r = config->promisors;
                free(r->partial_clone_filter);
+               free(r->advertised_filter);
                config->promisors = config->promisors->next;
                free(r);
        }
@@ -837,6 +838,7 @@ static void filter_promisor_remote(struct repository *repo,
        struct store_info *store_info = NULL;
        struct string_list_item *item;
        bool reload_config = false;
+       struct string_list accepted_filters = STRING_LIST_INIT_DUP;
 
        if (!repo_config_get_string_tmp(the_repository, "promisor.acceptfromserver", &accept_str)) {
                if (!*accept_str || !strcasecmp("None", accept_str))
@@ -879,6 +881,13 @@ static void filter_promisor_remote(struct repository *repo,
                                reload_config = true;
 
                        strvec_push(accepted, advertised->name);
+
+                       /* Capture advertised filters for accepted remotes */
+                       if (advertised->filter) {
+                               struct string_list_item *i;
+                               i = string_list_append(&accepted_filters, advertised->name);
+                               i->util = xstrdup(advertised->filter);
+                       }
                }
 
                promisor_info_free(advertised);
@@ -890,6 +899,25 @@ static void filter_promisor_remote(struct repository *repo,
 
        if (reload_config)
                repo_promisor_remote_reinit(repo);
+
+       /* Apply accepted remote filters to the stable repo state */
+       for_each_string_list_item(item, &accepted_filters) {
+               struct promisor_remote *r = repo_promisor_remote_find(repo, item->string);
+               if (r) {
+                       free(r->advertised_filter);
+                       r->advertised_filter = item->util;
+                       item->util = NULL;
+               }
+       }
+
+       string_list_clear(&accepted_filters, 1);
+
+       /* Mark the remotes as accepted in the repository state */
+       for (size_t i = 0; i < accepted->nr; i++) {
+               struct promisor_remote *r = repo_promisor_remote_find(repo, accepted->v[i]);
+               if (r)
+                       r->accepted = 1;
+       }
 }
 
 char *promisor_remote_reply(const char *info)
@@ -935,3 +963,33 @@ void mark_promisor_remotes_as_accepted(struct repository *r, const char *remotes
 
        string_list_clear(&accepted_remotes, 0);
 }
+
+char *promisor_remote_construct_filter(struct repository *repo)
+{
+       struct promisor_remote *r;
+       struct list_objects_filter_options filter_options = LIST_OBJECTS_FILTER_INIT;
+       struct strbuf err = STRBUF_INIT;
+       char *result = NULL;
+
+       promisor_remote_init(repo);
+
+       for (r = repo->promisor_remote_config->promisors; r; r = r->next) {
+               if (r->accepted && r->advertised_filter)
+                       if (gently_parse_list_objects_filter(&filter_options,
+                                                            r->advertised_filter,
+                                                            &err)) {
+                               warning(_("promisor remote '%s' advertised invalid filter '%s': %s"),
+                                       r->name, r->advertised_filter, err.buf);
+                               strbuf_reset(&err);
+                               continue;
+                       }
+       }
+
+       if (filter_options.choice)
+               result = xstrdup(expand_list_objects_filter_spec(&filter_options));
+
+       list_objects_filter_release(&filter_options);
+       strbuf_release(&err);
+
+       return result;
+}

diff --git a/promisor-remote.h b/promisor-remote.h
index 263d331a551b6ca80daa559d43fc61f7b081967e..d227299fd0d2763f31597678fe49318de0a11d85 100644 (file)
--- a/promisor-remote.h
+++ b/promisor-remote.h
@@ -15,6 +15,7 @@ struct object_id;
 struct promisor_remote {
        struct promisor_remote *next;
        char *partial_clone_filter;
+       char *advertised_filter;
        unsigned int accepted : 1;
        const char name[FLEX_ARRAY];
 };
@@ -67,4 +68,10 @@ void mark_promisor_remotes_as_accepted(struct repository *repo, const char *remo
  */
 int repo_has_accepted_promisor_remote(struct repository *r);
 
+/*
+ * Use the filters from the accepted remotes to create a combined
+ * filter (useful in `--filter=auto` mode).
+ */
+char *promisor_remote_construct_filter(struct repository *repo);
+
 #endif /* PROMISOR_REMOTE_H */