Datum age_vertex_stats()

in src/backend/utils/adt/age_global_graph.c [1260:1373]

• 73 lines of code
• 6 McCabe index (conditional complexity)

Datum age_vertex_stats(PG_FUNCTION_ARGS)
{
    GRAPH_global_context *ggctx = NULL;
    vertex_entry *ve = NULL;
    ListGraphId *edges = NULL;
    agtype_value *agtv_vertex = NULL;
    agtype_value *agtv_temp = NULL;
    agtype_value agtv_integer;
    agtype_in_state result;
    char *graph_name = NULL;
    Oid graph_oid = InvalidOid;
    graphid vid = 0;
    int64 self_loops = 0;
    int64 degree = 0;

    /* the graph name is required, but this generally isn't user supplied */
    if (PG_ARGISNULL(0))
    {
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                 errmsg("vertex_stats: graph name cannot be NULL")));
    }

    /* get the graph name */
    agtv_temp = get_agtype_value("vertex_stats", AG_GET_ARG_AGTYPE_P(0),
                                 AGTV_STRING, true);

    /* we need the vertex */
    if (PG_ARGISNULL(1))
    {
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                 errmsg("vertex_stats: vertex cannot be NULL")));
    }

    /* get the vertex */
    agtv_vertex = get_agtype_value("vertex_stats", AG_GET_ARG_AGTYPE_P(1),
                                   AGTV_VERTEX, true);

    graph_name = pnstrdup(agtv_temp->val.string.val,
                          agtv_temp->val.string.len);

    /* get the graph oid */
    graph_oid = get_graph_oid(graph_name);

    /*
     * Create or retrieve the GRAPH global context for this graph. This function
     * will also purge off invalidated contexts.
     */
    ggctx = manage_GRAPH_global_contexts(graph_name, graph_oid);

    /* free the graph name */
    pfree_if_not_null(graph_name);

    /* get the id */
    agtv_temp = GET_AGTYPE_VALUE_OBJECT_VALUE(agtv_vertex, "id");
    vid = agtv_temp->val.int_value;

    /* get the vertex entry */
    ve = get_vertex_entry(ggctx, vid);

    /* zero the state */
    memset(&result, 0, sizeof(agtype_in_state));

    /* start the object */
    result.res = push_agtype_value(&result.parse_state, WAGT_BEGIN_OBJECT,
                                   NULL);
    /* store the id */
    result.res = push_agtype_value(&result.parse_state, WAGT_KEY,
                                   string_to_agtype_value("id"));
    result.res = push_agtype_value(&result.parse_state, WAGT_VALUE, agtv_temp);

    /* store the label */
    agtv_temp = GET_AGTYPE_VALUE_OBJECT_VALUE(agtv_vertex, "label");
    result.res = push_agtype_value(&result.parse_state, WAGT_KEY,
                                   string_to_agtype_value("label"));
    result.res = push_agtype_value(&result.parse_state, WAGT_VALUE, agtv_temp);

    /* set up an integer for returning values */
    agtv_temp = &agtv_integer;
    agtv_temp->type = AGTV_INTEGER;
    agtv_temp->val.int_value = 0;

    /* get and store the self_loops */
    edges = get_vertex_entry_edges_self(ve);
    self_loops = (edges != NULL) ? get_list_size(edges) : 0;
    agtv_temp->val.int_value = self_loops;
    result.res = push_agtype_value(&result.parse_state, WAGT_KEY,
                                   string_to_agtype_value("self_loops"));
    result.res = push_agtype_value(&result.parse_state, WAGT_VALUE, agtv_temp);

    /* get and store the in_degree */
    edges = get_vertex_entry_edges_in(ve);
    degree = (edges != NULL) ? get_list_size(edges) : 0;
    agtv_temp->val.int_value = degree + self_loops;
    result.res = push_agtype_value(&result.parse_state, WAGT_KEY,
                                   string_to_agtype_value("in_degree"));
    result.res = push_agtype_value(&result.parse_state, WAGT_VALUE, agtv_temp);

    /* get and store the out_degree */
    edges = get_vertex_entry_edges_out(ve);
    degree = (edges != NULL) ? get_list_size(edges) : 0;
    agtv_temp->val.int_value = degree + self_loops;
    result.res = push_agtype_value(&result.parse_state, WAGT_KEY,
                                   string_to_agtype_value("out_degree"));
    result.res = push_agtype_value(&result.parse_state, WAGT_VALUE, agtv_temp);

    /* close the object */
    result.res = push_agtype_value(&result.parse_state, WAGT_END_OBJECT, NULL);

    result.res->type = AGTV_OBJECT;

    PG_RETURN_POINTER(agtype_value_to_agtype(result.res));
}