DatabaseContext::lookForGridInfo(): do not trigger network activity i…

…n PROJ_GRID_AVAILABILITY_KNOWN_AVAILABLE mode when all grids are known (fixes OSGeo#4075)
rouault · Mar 14, 2024 · 3925116 · 3925116
1 parent e6a0514
commit 3925116
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Showing 2 changed files with 88 additions and 19 deletions.
diff --git a/src/iso19111/factory.cpp b/src/iso19111/factory.cpp
@@ -3324,14 +3324,18 @@ bool DatabaseContext::lookForGridInfo(
     url.clear();
     openLicense = false;
     directDownload = false;
-
-    fullFilename.resize(2048);
-    int errno_before = proj_context_errno(ctxt);
-    gridAvailable = NS_PROJ::FileManager::open_resource_file(
-                        ctxt, projFilename.c_str(), &fullFilename[0],
-                        fullFilename.size() - 1) != nullptr;
-    proj_context_errno_set(ctxt, errno_before);
-    fullFilename.resize(strlen(fullFilename.c_str()));
+    gridAvailable = false;
+
+    const auto resolveFullFilename = [ctxt, &fullFilename, &projFilename]() {
+        fullFilename.resize(2048);
+        const int errno_before = proj_context_errno(ctxt);
+        bool lGridAvailable = NS_PROJ::FileManager::open_resource_file(
+                                  ctxt, projFilename.c_str(), &fullFilename[0],
+                                  fullFilename.size() - 1) != nullptr;
+        proj_context_errno_set(ctxt, errno_before);
+        fullFilename.resize(strlen(fullFilename.c_str()));
+        return lGridAvailable;
+    };
 
     auto res =
         d->run("SELECT "
@@ -3363,7 +3367,7 @@ bool DatabaseContext::lookForGridInfo(
             old_proj_grid_name == projFilename) {
             std::string fullFilenameNewName;
             fullFilenameNewName.resize(2048);
-            errno_before = proj_context_errno(ctxt);
+            const int errno_before = proj_context_errno(ctxt);
             bool gridAvailableWithNewName =
                 pj_find_file(ctxt, proj_grid_name.c_str(),
                              &fullFilenameNewName[0],
@@ -3376,8 +3380,17 @@ bool DatabaseContext::lookForGridInfo(
             }
         }
 
-        if (considerKnownGridsAsAvailable &&
+        if (!gridAvailable && considerKnownGridsAsAvailable &&
             (!packageName.empty() || (!url.empty() && openLicense))) {
+
+            // In considerKnownGridsAsAvailable mode, try to fetch the local
+            // file name if it exists, but do not attempt network access.
+            const auto network_was_enabled =
+                proj_context_is_network_enabled(ctxt);
+            proj_context_set_enable_network(ctxt, false);
+            (void)resolveFullFilename();
+            proj_context_set_enable_network(ctxt, network_was_enabled);
+
             gridAvailable = true;
         }
 
@@ -3391,7 +3404,13 @@ bool DatabaseContext::lookForGridInfo(
         }
         info.directDownload = directDownload;
         info.openLicense = openLicense;
+
+        if (!gridAvailable) {
+            gridAvailable = resolveFullFilename();
+        }
     } else {
+        gridAvailable = resolveFullFilename();
+
         if (starts_with(fullFilename, "http://") ||
             starts_with(fullFilename, "https://")) {
             url = fullFilename;

diff --git a/test/unit/test_network.cpp b/test/unit/test_network.cpp
@@ -1264,26 +1264,28 @@ TEST(networking, network_endpoint_api) {
 
 static PROJ_NETWORK_HANDLE *dummy_open_cbk(PJ_CONTEXT *, const char *,
                                            unsigned long long, size_t, void *,
-                                           size_t *, size_t, char *, void *) {
-    assert(false);
+                                           size_t *, size_t, char *,
+                                           void *pUserData) {
+    *static_cast<bool *>(pUserData) = true;
     return nullptr;
 }
 
-static void dummy_close_cbk(PJ_CONTEXT *, PROJ_NETWORK_HANDLE *, void *) {
-    assert(false);
+static void dummy_close_cbk(PJ_CONTEXT *, PROJ_NETWORK_HANDLE *,
+                            void *pUserData) {
+    *static_cast<bool *>(pUserData) = true;
 }
 
 static const char *dummy_get_header_value_cbk(PJ_CONTEXT *,
                                               PROJ_NETWORK_HANDLE *,
-                                              const char *, void *) {
-    assert(false);
+                                              const char *, void *pUserData) {
+    *static_cast<bool *>(pUserData) = true;
     return nullptr;
 }
 
 static size_t dummy_read_range_cbk(PJ_CONTEXT *, PROJ_NETWORK_HANDLE *,
                                    unsigned long long, size_t, void *, size_t,
-                                   char *, void *) {
-    assert(false);
+                                   char *, void *pUserData) {
+    *static_cast<bool *>(pUserData) = true;
     return 0;
 }
 
@@ -1332,12 +1334,14 @@ TEST(networking, cache_basic) {
     proj_cleanup();
 
     // Check that a second access doesn't trigger any network activity
+    bool networkActivity = false;
     ASSERT_TRUE(proj_context_set_network_callbacks(
         ctx, dummy_open_cbk, dummy_close_cbk, dummy_get_header_value_cbk,
-        dummy_read_range_cbk, nullptr));
+        dummy_read_range_cbk, &networkActivity));
     P = proj_create(ctx, pipeline);
     ASSERT_NE(P, nullptr);
     proj_destroy(P);
+    EXPECT_FALSE(networkActivity);
 
     proj_context_destroy(ctx);
 }
@@ -2020,4 +2024,50 @@ TEST(networking, pyproj_issue_1192) {
 
 #endif
 
+// ---------------------------------------------------------------------------
+
+#ifdef CURL_ENABLED
+
+TEST(networking, do_not_attempt_network_access_known_available_network_on) {
+
+    // Check that proj_create_operations() itself does not trigger network
+    // activity in enable_network == true and
+    // PROJ_GRID_AVAILABILITY_KNOWN_AVAILABLE mode when all grids are known.
+
+    const auto doTest = [](PJ_CONTEXT *ctxt) {
+        auto factory_context =
+            proj_create_operation_factory_context(ctxt, nullptr);
+        proj_operation_factory_context_set_grid_availability_use(
+            ctxt, factory_context, PROJ_GRID_AVAILABILITY_KNOWN_AVAILABLE);
+        proj_operation_factory_context_set_spatial_criterion(
+            ctxt, factory_context, PROJ_SPATIAL_CRITERION_PARTIAL_INTERSECTION);
+        auto from = proj_create(ctxt, "EPSG:4326");
+        auto to = proj_create(ctxt, "EPSG:4267");
+        auto pj_operations =
+            proj_create_operations(ctxt, from, to, factory_context);
+        proj_destroy(from);
+        proj_destroy(to);
+        auto num_operations = proj_list_get_count(pj_operations);
+        EXPECT_GE(num_operations, 10);
+        proj_operation_factory_context_destroy(factory_context);
+        proj_list_destroy(pj_operations);
+    };
+
+    auto ctx = proj_context_create();
+    proj_context_set_enable_network(ctx, true);
+
+    // Check that we don't trigger any network activity
+    bool networkActivity = false;
+    ASSERT_TRUE(proj_context_set_network_callbacks(
+        ctx, dummy_open_cbk, dummy_close_cbk, dummy_get_header_value_cbk,
+        dummy_read_range_cbk, &networkActivity));
+
+    doTest(ctx);
+    EXPECT_FALSE(networkActivity);
+
+    proj_context_destroy(ctx);
+}
+
+#endif
+
 } // namespace