t.connect: Add formats

temporal/CMakeLists.txt

@@ -63,7 +63,7 @@ if(WITH_DOCS)
   generate_docs(temporalintro TARGET ALL_TEMPORAL_MODULES)
 endif()
 
-build_program_in_subdir(t.connect DEPENDS grass_gis grass_temporal)
+build_program_in_subdir(t.connect DEPENDS grass_gis grass_temporal grass_parson)
 
 foreach(temporal_DIR ${temporal_script_modules_list})
   build_script_in_subdir(${temporal_DIR})

temporal/t.connect/Makefile

@@ -1,6 +1,6 @@
 MODULE_TOPDIR = ../..
 
-LIBES = $(TEMPORALLIB) $(GISLIB)
+LIBES = $(TEMPORALLIB) $(GISLIB) $(PARSONLIB)
 DEPENDENCIES = $(TEMPORALDEP) $(GISDEP)
 
 PGM = t.connect

temporal/t.connect/main.c

@@ -18,14 +18,21 @@
 #include <grass/gis.h>
 #include <grass/temporal.h>
 #include <grass/glocale.h>
+#include <grass/gjson.h>
+
+enum OutputFormat { PLAIN, SHELL, JSON };
 
 int main(int argc, char *argv[])
 {
     dbConnection conn;
     struct Flag *print, *check_set_default, *def, *sh;
-    struct Option *driver, *database;
+    struct Option *driver, *database, *format_opt;
     struct GModule *module;
 
+    enum OutputFormat format;
+    G_JSON_Value *root_value = NULL;
+    G_JSON_Object *root_object = NULL;
+
     /* Initialize the GIS calls */
     G_gisinit(argv[0]);
 
@@ -42,6 +49,15 @@ int main(int argc, char *argv[])
     print->description = _("Print current connection parameters and exit");
     print->guisection = _("Print");
 
+    format_opt = G_define_standard_option(G_OPT_F_FORMAT);
+    format_opt->options = "plain,shell,json";
+    format_opt->required = NO;
+    format_opt->answer = "plain";
+    format_opt->descriptions = _("plain;Plain text output;"
+                                 "shell;Shell script style output;"
+                                 "json;JSON (JavaScript Object Notation)");
+    format_opt->guisection = _("Print");
+
     check_set_default = G_define_flag();
     check_set_default->key = 'c';
     check_set_default->description =
@@ -56,9 +72,12 @@ int main(int argc, char *argv[])
 
     sh = G_define_flag();
     sh->key = 'g';
+    sh->label = _("Print current connection parameters using shell style "
+                  "and exit [deprecated]");
     sh->description =
-        _("Print current connection parameter in shell style and exit");
-    sh->guisection = _("Set");
+        _("This flag is deprecated and will be removed in a future "
+          "release. Use format=shell instead.");
+    sh->guisection = _("Print");
 
     driver = G_define_standard_option(G_OPT_DB_DRIVER);
     driver->options = "sqlite,pg";
@@ -72,31 +91,102 @@ int main(int argc, char *argv[])
     if (G_parser(argc, argv))
         exit(EXIT_FAILURE);
 
+    if (format_opt->answer != NULL) {
+        if (strcmp(format_opt->answer, "json") == 0) {
+            format = JSON;
+            root_value = G_json_value_init_object();
+            if (root_value == NULL) {
+                G_fatal_error(
+                    _("Failed to initialize JSON object. Out of memory?"));
+            }
+            root_object = G_json_object(root_value);
+        }
+        else if (strcmp(format_opt->answer, "shell") == 0) {
+            format = SHELL;
+        }
+        else {
+            format = PLAIN;
+        }
+    }
+    else {
+        format = PLAIN;
+    }
+
+    if (sh->answer) {
+        G_verbose_message(
+            _("Flag 'g' is deprecated and will be removed in a future "
+              "release. Please use format=shell instead."));
+        if (format == JSON) {
+            /* Free memory before failing to prevent memory leaks */
+            if (root_value)
+                G_json_value_free(root_value);
+            G_fatal_error(_("The -g flag cannot be used with format=json. "
+                            "Please select only one output format."));
+        }
+        format = SHELL;
+        print->answer = 1;
+    }
+
+    if (format != PLAIN && !print->answer) {
+        G_fatal_error(
+            _("The -p flag is required when using the format option."));
+    }
+
     if (print->answer) {
-        if (sh->answer) {
-            if (tgis_get_connection(&conn) == DB_OK) {
+        if (tgis_get_connection(&conn) == DB_OK) {
+            switch (format) {
+            case SHELL:
                 fprintf(stdout, "driver=%s\n",
                         conn.driverName ? conn.driverName : "");
                 fprintf(stdout, "database=%s\n",
                         conn.databaseName ? conn.databaseName : "");
-            }
-            else
-                G_fatal_error(_("Temporal GIS database connection not defined. "
-                                "Run t.connect."));
-        }
-        else {
-            /* get and print connection */
-            if (tgis_get_connection(&conn) == DB_OK) {
+                break;
+
+            case PLAIN:
                 fprintf(stdout, "driver:%s\n",
                         conn.driverName ? conn.driverName : "");
                 fprintf(stdout, "database:%s\n",
                         conn.databaseName ? conn.databaseName : "");
+                break;
+
+            case JSON:
+                if (conn.driverName)
+                    G_json_object_set_string(root_object, "driver",
+                                             conn.driverName);
+                else
+                    G_json_object_set_null(root_object, "driver");
+
+                if (conn.databaseName)
+                    G_json_object_set_string(root_object, "database",
+                                             conn.databaseName);
+                else
+                    G_json_object_set_null(root_object, "database");
+                break;
+            }
+        }
+        else {
+            if (root_value)
+                G_json_value_free(root_value);
+            G_fatal_error(_("Temporal GIS database connection not defined. "
+                            "Run t.connect."));
+        }
+
+        if (format == JSON) {
+            char *json_string = G_json_serialize_to_string_pretty(root_value);
+            if (!json_string) {
+                G_json_value_free(root_value);
+                G_fatal_error(_("Failed to serialize JSON to pretty format."));
             }
-            else
-                G_fatal_error(_("Temporal GIS database connection not defined. "
-                                "Run t.connect."));
+
+            fputs(json_string, stdout);
+            fputc('\n', stdout);
+
+            G_json_free_serialized_string(json_string);
+            G_json_value_free(root_value);
         }
 
+        fflush(stdout);
+
         exit(EXIT_SUCCESS);
     }
 

temporal/t.connect/t.connect.md

@@ -5,10 +5,11 @@ default setting is that the temporal database of type *sqlite3* is
 located in the current mapset directory.
 
 The **-p** flag will display the current temporal database connection
-parameters.
+parameters. Use the **format** option to specify the output format: `plain`,
+ `shell`, or `json` — with `plain` being the default.
 
-The **-pg** flag will display the current temporal database connection
-parameters using shell style.
+The **-g** flag is deprecated and will be removed in a future release. Please
+use **format=shell** option with the **-p** flag instead.
 
 The **-c** flag will silently check if the temporal database connection
 parameters have been set, and if not will set them to use GRASS's

temporal/t.connect/tests/test_t_connect.py

@@ -1,6 +1,8 @@
 """Test current baseline functionality of t.connect"""
 
-from grass.tools import Tools
+import pytest
+
+from grass.tools import ToolError, Tools
 
 
 def test_no_connection(empty_session):
@@ -28,8 +30,35 @@ def test_print_shell(t_connect_session):
     """Check that the shell format prints correctly."""
     tools = Tools(session=t_connect_session.session)
 
-    result = tools.t_connect(flags="pg")
+    result = tools.t_connect(flags="p", format="shell")
     lines = result.text_split("\n")
 
     assert "driver=sqlite" in lines
     assert "database=$GISDBASE/$LOCATION_NAME/$MAPSET/tgis/sqlite.db" in lines
+
+
+def test_print_json(t_connect_session):
+    """Check that the JSON format parses correctly and matches connection values."""
+    tools = Tools(session=t_connect_session.session)
+
+    result = tools.t_connect(flags="p", format="json")
+
+    assert result["driver"] == "sqlite"
+    assert result["database"] == "$GISDBASE/$LOCATION_NAME/$MAPSET/tgis/sqlite.db"
+
+
+@pytest.mark.parametrize("output_format", ["shell", "json"])
+def test_missing_print_flag(t_connect_session, output_format):
+    """Ensure omitting the -p flag when requesting a format triggers a fatal error."""
+    tools = Tools(session=t_connect_session.session)
+
+    with pytest.raises(ToolError):
+        tools.t_connect(format=output_format)
+
+
+def test_incompatible_flags(t_connect_session):
+    """Ensure combining the deprecated -g flag with format=json triggers a fatal error."""
+    tools = Tools(session=t_connect_session.session)
+
+    with pytest.raises(ToolError):
+        tools.t_connect(flags="g", format="json")