1195 Formatter for date to have consistent Format (#1198)

- Formatter to print date objects

Co-authored-by: reneSchm <49305466+reneSchm@users.noreply.github.com>

cpp/memilio/utils/date.h

@@ -21,6 +21,7 @@
 #define EPI_UTILS_DATE_H
 
 #include "memilio/io/io.h"
+#include "memilio/utils/logging.h"
 #include <string>
 #include <iostream>
 #include <tuple>
@@ -106,11 +107,27 @@ struct Date {
     //@}
 
     /**
-     * gtest printer.
+     * Formats the date into a string in ISO 8601 format (YYYY-MM-DD).
+     * @return A string representing the date in ISO 8601 format.
      */
-    friend void PrintTo(const Date& self, std::ostream* os)
+    std::string to_iso_string() const
     {
-        *os << self.year << "." << self.month << "." << self.day;
+        // the format after ":" reads as
+        // 1) '0' -> fill with zeros
+        // 2) '>' -> align text right
+        // 3) '4' or '2' -> specify the width (4 for year, 2 for month and day)
+        return fmt::format("{:0>4}-{:0>2}-{:0>2}", year, month, day);
+    }
+
+    /**
+     * Overload for stream operator to use the ISO 8601 format.
+     * @param os Output stream.
+     * @param date Date to output.
+     * @return Reference to the output stream.
+     */
+    friend std::ostream& operator<<(std::ostream& os, const Date& date)
+    {
+        return os << date.to_iso_string();
     }
 
     /**
@@ -156,6 +173,15 @@ struct Date {
     static constexpr std::array<int, 12> month_lengths_leap_year = {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
 };
 
+/**
+ * @brief Format date objects using the ISO notation for logging with spdlog.
+ * @param d date object.
+ */
+inline std::string format_as(const mio::Date& d)
+{
+    return d.to_iso_string();
+}
+
 /**
  * @brief Computes the length of a month for a given date.
  * @param date date.

cpp/models/ide_secir/parameters_io.h

@@ -288,17 +288,11 @@ IOResult<void> set_initial_flows(Model& model, const ScalarType dt, const std::v
             return a.date < b.date;
         });
         auto min_date       = min_date_entry->date;
-
-        std::string min_date_string =
-            std::to_string(min_date.day) + "." + std::to_string(min_date.month) + "." + std::to_string(min_date.year);
         // Get first date that is needed.
-        mio::Date min_offset_date          = offset_date_by_days(date, int(min_offset_needed));
-        std::string min_offset_date_string = std::to_string(min_offset_date.day) + "." +
-                                             std::to_string(min_offset_date.month) + "." +
-                                             std::to_string(min_offset_date.year);
-        log_warning("RKI data is needed from " + min_offset_date_string +
-                    " to compute initial values. RKI data is only available from " + min_date_string +
-                    ". Missing dates were set to 0.");
+        mio::Date min_offset_date = offset_date_by_days(date, int(min_offset_needed));
+        log_warning("RKI data is needed from {} to compute initial values. RKI data is only available from {}. Missing "
+                    "dates were set to 0.",
+                    min_offset_date, min_date);
     }
 
     //--- Calculate the flows "after" InfectedNoSymptomsToInfectedSymptoms (that were set above using rki_data). ---

cpp/models/ode_secir/parameters_io.h

@@ -143,9 +143,8 @@ IOResult<void> set_confirmed_cases_data(std::vector<Model<FP>>& model, std::vect
             }
         }
         else {
-            log_warning("No infections reported on date " + std::to_string(date.year) + "-" +
-                        std::to_string(date.month) + "-" + std::to_string(date.day) + " for region " +
-                        std::to_string(region[node]) + ". Population data has not been set.");
+            log_warning("No infections reported on date {} for region {}. Population data has not been set.", date,
+                        region[node]);
         }
     }
     return success();
@@ -196,8 +195,9 @@ IOResult<void> set_divi_data(std::vector<Model<FP>>& model, const std::string& p
 {
     // DIVI dataset will no longer be updated from CW29 2024 on.
     if (!is_divi_data_available(date)) {
-        log_warning("No DIVI data available for date: {}-{}-{}", date.year, date.month, date.day,
-                    ". ICU compartment will be set based on Case data.");
+        log_warning("No DIVI data available for date: {}. "
+                    "ICU compartment will be set based on Case data.",
+                    date);
         return success();
     }
     std::vector<double> sum_mu_I_U(vregion.size(), 0);

cpp/models/ode_secirts/parameters_io.h

@@ -421,9 +421,9 @@ set_confirmed_cases_data(std::vector<Model>& model, const std::vector<ConfirmedC
             }
         }
         if (std::accumulate(num_InfectedSymptoms[county].begin(), num_InfectedSymptoms[county].end(), 0.0) == 0) {
-            log_warning("No infections for unvaccinated reported on date " + std::to_string(date.year) + "-" +
-                        std::to_string(date.month) + "-" + std::to_string(date.day) + " for region " +
-                        std::to_string(region[county]) + ". Population data has not been set.");
+            log_warning(
+                "No infections for unvaccinated reported on date {} for region {}. Population data has not been set.",
+                date, region[county]);
         }
     }
 
@@ -478,9 +478,9 @@ set_confirmed_cases_data(std::vector<Model>& model, const std::vector<ConfirmedC
                 num_timm1[county][i];
         }
         if (std::accumulate(num_InfectedSymptoms[county].begin(), num_InfectedSymptoms[county].end(), 0.0) == 0) {
-            log_warning("No infections for partially vaccinated reported on date " + std::to_string(date.year) + "-" +
-                        std::to_string(date.month) + "-" + std::to_string(date.day) + " for region " +
-                        std::to_string(region[county]) + ". Population data has not been set.");
+            log_warning("No infections for partially vaccinated reported on date {} for region {}. "
+                        "Population data has not been set.",
+                        date, region[county]);
         }
     }
 
@@ -536,9 +536,9 @@ set_confirmed_cases_data(std::vector<Model>& model, const std::vector<ConfirmedC
                 num_timm2[county][i];
         }
         if (std::accumulate(num_InfectedSymptoms[county].begin(), num_InfectedSymptoms[county].end(), 0.0) == 0) {
-            log_warning("No infections for vaccinated reported on date " + std::to_string(date.year) + "-" +
-                        std::to_string(date.month) + "-" + std::to_string(date.day) + " for region " +
-                        std::to_string(region[county]) + ". Population data has not been set.");
+            log_warning("No infections for vaccinated reported on date {} for region {}. "
+                        "Population data has not been set.",
+                        date, region[county]);
         }
     }
     return success();
@@ -663,8 +663,9 @@ IOResult<void> set_divi_data(std::vector<Model>& model, const std::string& path,
 {
     // DIVI dataset will no longer be updated from CW29 2024 on.
     if (!is_divi_data_available(date)) {
-        log_warning("No DIVI data available for date: {}-{}-{}", date.year, date.month, date.day,
-                    ". ICU compartment will be set based on Case data.");
+        log_warning("No DIVI data available for date: {}. "
+                    "ICU compartment will be set based on Case data.",
+                    date);
         return success();
     }
     std::vector<FP> sum_mu_I_U(vregion.size(), 0);

cpp/models/ode_secirvvs/parameters_io.h

@@ -196,9 +196,9 @@ IOResult<void> set_confirmed_cases_data(std::vector<Model>& model,
 
         // }
         if (std::accumulate(num_InfectedSymptoms[county].begin(), num_InfectedSymptoms[county].end(), 0.0) == 0) {
-            log_warning("No infections for unvaccinated reported on date " + std::to_string(date.year) + "-" +
-                        std::to_string(date.month) + "-" + std::to_string(date.day) + " for region " +
-                        std::to_string(region[county]) + ". Population data has not been set.");
+            log_warning(
+                "No infections for unvaccinated reported on date {} for region {}. Population data has not been set.",
+                date, region[county]);
         }
     }
 
@@ -284,9 +284,9 @@ IOResult<void> set_confirmed_cases_data(std::vector<Model>& model,
         }
         // }
         if (std::accumulate(num_InfectedSymptoms[county].begin(), num_InfectedSymptoms[county].end(), 0.0) == 0) {
-            log_warning("No infections for partially vaccinated reported on date " + std::to_string(date.year) + "-" +
-                        std::to_string(date.month) + "-" + std::to_string(date.day) + " for region " +
-                        std::to_string(region[county]) + ". Population data has not been set.");
+            log_warning("No infections for partially vaccinated reported on date {} for region {}. "
+                        "Population data has not been set.",
+                        date, region[county]);
         }
     }
 
@@ -370,9 +370,9 @@ IOResult<void> set_confirmed_cases_data(std::vector<Model>& model,
             }
         }
         if (std::accumulate(num_InfectedSymptoms[county].begin(), num_InfectedSymptoms[county].end(), 0.0) == 0) {
-            log_warning("No infections for vaccinated reported on date " + std::to_string(date.year) + "-" +
-                        std::to_string(date.month) + "-" + std::to_string(date.day) + " for region " +
-                        std::to_string(region[county]) + ". Population data has not been set.");
+            log_warning("No infections for vaccinated reported on date {} for region {}. "
+                        "Population data has not been set.",
+                        date, region[county]);
         }
     }
 
@@ -428,8 +428,9 @@ IOResult<void> set_divi_data(std::vector<Model>& model, const std::string& path,
 {
     // DIVI dataset will no longer be updated from CW29 2024 on.
     if (!is_divi_data_available(date)) {
-        log_warning("No DIVI data available for date: {}-{}-{}", date.year, date.month, date.day,
-                    ". ICU compartment will be set based on Case data.");
+        log_warning("No DIVI data available for date: {}. "
+                    "ICU compartment will be set based on Case data.",
+                    date);
         return success();
     }
     std::vector<double> sum_mu_I_U(vregion.size(), 0);

cpp/tests/test_date.cpp

@@ -170,3 +170,45 @@ TEST(TestDate, getOffset)
     offset = mio::get_offset_in_days({2019, 11, 30}, {2020, 11, 30});
     EXPECT_EQ(offset, -366);
 }
+
+TEST(TestDate, toIsoString)
+{
+    EXPECT_EQ(mio::Date(2020, 9, 2).to_iso_string(), "2020-09-02");
+    EXPECT_EQ(mio::Date(2021, 8, 30).to_iso_string(), "2021-08-30");
+    EXPECT_EQ(mio::Date(2021, 3, 4).to_iso_string(), "2021-03-04");
+    EXPECT_EQ(mio::Date(2021, 1, 1).to_iso_string(), "2021-01-01");
+    EXPECT_EQ(mio::Date(2020, 2, 29).to_iso_string(), "2020-02-29");
+}
+
+TEST(TestDate, streamOutput)
+{
+    std::ostringstream oss1;
+    oss1 << mio::Date(2020, 9, 2);
+    EXPECT_EQ(oss1.str(), "2020-09-02");
+
+    std::ostringstream oss2;
+    oss2 << mio::Date(2021, 8, 30);
+    EXPECT_EQ(oss2.str(), "2021-08-30");
+
+    std::ostringstream oss3;
+    oss3 << mio::Date(2021, 3, 4);
+    EXPECT_EQ(oss3.str(), "2021-03-04");
+
+    std::ostringstream oss4;
+    oss4 << mio::Date(2021, 1, 1);
+    EXPECT_EQ(oss4.str(), "2021-01-01");
+
+    std::ostringstream oss5;
+    oss5 << mio::Date(2020, 2, 29);
+    EXPECT_EQ(oss5.str(), "2020-02-29");
+}
+
+TEST(TestDate, formatViaFmt)
+{
+    EXPECT_EQ(fmt::format("{}", mio::Date(2020, 9, 2)), "2020-09-02");
+    EXPECT_EQ(fmt::format("{}", mio::Date(2021, 8, 30)), "2021-08-30");
+    EXPECT_EQ(fmt::format("{}", mio::Date(2021, 1, 1)), "2021-01-01");
+    EXPECT_EQ(fmt::format("{}", mio::Date(2020, 2, 29)), "2020-02-29");
+    EXPECT_EQ(fmt::format("{}", mio::Date(2021, 3, 4)), "2021-03-04");
+    EXPECT_EQ(fmt::format("Todays date is: {}", mio::Date(2021, 12, 31)), "Todays date is: 2021-12-31");
+}