Merge pull request #6 from mongodb-labs/feature/crud-tut

[CDRIVER-5662] Tutorials for simple CRUD, and some more convience APIs

Author: vector-of-bool

.clang-format

@@ -82,6 +82,9 @@ IncludeCategories:
 InsertNewlineAtEOF: true
 IfMacros:
   - mlib_math_catch
+  - amongoc_if_error
+ForEachMacros:
+  - bson_foreach
 AllowBreakBeforeNoexceptSpecifier: Always
 ---
 # For some reason, Clang sees some files as Objective-C. Add this section just to appease it.

Makefile

@@ -35,7 +35,7 @@ build:
 test: build
 	cmake -E chdir "$(BUILD_DIR)" ctest -C "$(CONFIG)" --output-on-failure -j8
 
-all_sources := $(shell find $(THIS_DIR)/src/ $(THIS_DIR)/include/ $(THIS_DIR)/tests/ -name '*.c' -o -name '*.cpp' -o -name '*.h' -o -name '*.hpp')
+all_sources := $(shell find $(THIS_DIR)/src/ $(THIS_DIR)/include/ $(THIS_DIR)/tests/ $(THIS_DIR)/docs/ -name '*.c' -o -name '*.cpp' -o -name '*.h' -o -name '*.hpp')
 format-check: poetry-install
 	$(POETRY) run python tools/include-fixup.py --check
 	$(POETRY) run $(MAKE) _format-check

docs/conf.py

@@ -229,6 +229,7 @@ def generate_sphinx_inventory(
 .. |static| replace:: :cpp:`static`
 .. |const| replace:: :cpp:`const`
 .. |void| replace:: :cpp:`void`
+.. |char| replace:: :cpp:`char`
 .. |A| replace:: :math:`A`
 .. |A'| replace:: :math:`A'`
 .. |B| replace:: :math:`B`
@@ -337,6 +338,7 @@ def merge_domaindata(self, docnames: list[str], otherdata: dict[str, Any]) -> No
             "default_loop",
             "client",
             "collection",
+            "cursor",
         )
     ),
     *(
@@ -414,6 +416,8 @@ class CustomCppLexer(CppLexer):
             (r"bson_type_\w+\b", token.Name.Constant),
             # Other macro
             (r"bson_foreach\w*\b", token.Keyword),
+            (r"amongoc_declmsg\b", token.Keyword),
+            (r"amongoc_if_error\b", token.Keyword),
             inherit,
         ],
     }

docs/how-to/communicate.example.c

@@ -1,10 +1,9 @@
 #include <amongoc/amongoc.h>
 
-#include "bson/view.h"
+#include <bson/format.h>
 #include <bson/iterator.h>
 #include <bson/mut.h>
-
-#include "mlib/str.h"
+#include <bson/view.h>
 
 /**
  * @brief Shared state for the application. This is passed through the app as pointer stored
@@ -15,11 +14,6 @@ typedef struct app_state {
     amongoc_client* client;
 } app_state;
 
-/**
- * @brief Write the content of a BSON document in JSON-like format to the given output
- */
-static void print_bson(FILE* into, bson_view doc, mlib_str_view indent);
-
 /** after_hello()
  * @brief Handle the `hello` response from the server
  *
@@ -32,7 +26,7 @@ amongoc_box after_hello(amongoc_box state_ptr, amongoc_status*, amongoc_box resp
     bson_view resp = bson_view_from(amongoc_box_cast(bson_doc, resp_data));
     // Just print the response message
     fprintf(stdout, "Got response: ");
-    print_bson(stdout, resp, mlib_str_view_from(""));
+    bson_write_repr(stdout, resp);
     fputs("\n", stdout);
     amongoc_box_destroy(resp_data);
     return amongoc_nil;
@@ -72,8 +66,12 @@ int main(int argc, char const* const* argv) {
     }
     const char* const uri = argv[1];
 
-    amongoc_loop loop;
-    amongoc_default_loop_init(&loop);
+    amongoc_loop   loop;
+    amongoc_status status = amongoc_default_loop_init(&loop);
+    amongoc_if_error (status, msg) {
+        fprintf(stderr, "Error setting up the event loop: %s\n", msg);
+        return 2;
+    }
 
     struct app_state state = {0};
 
@@ -88,8 +86,7 @@ int main(int argc, char const* const* argv) {
                      amongoc_box_pointer(&state),
                      after_connect_say_hello);
 
-    amongoc_status    fin_status = amongoc_okay;
-    amongoc_operation op         = amongoc_tie(em, &fin_status, NULL, mlib_default_allocator);
+    amongoc_operation op = amongoc_tie(em, &status);
     amongoc_start(&op);
     amongoc_default_loop_run(&loop);
     amongoc_operation_delete(op);
@@ -98,71 +95,13 @@ int main(int argc, char const* const* argv) {
     amongoc_client_delete(state.client);
     amongoc_default_loop_destroy(&loop);
 
-    if (amongoc_is_error(fin_status)) {
-        char* m = amongoc_status_strdup_message(fin_status);
-        fprintf(stderr, "An error occurred: %s\n", m);
-        free(m);
+    // Final status
+    amongoc_if_error (status, msg) {
+        fprintf(stderr, "An error occurred: %s\n", msg);
         return 2;
     } else {
         printf("Okay\n");
         return 0;
     }
 }
 // end.
-
-static void print_bson(FILE* into, bson_view doc, mlib_str_view indent) {
-    fprintf(into, "{\n");
-    bson_foreach(it, doc) {
-        mlib_str_view str = bson_key(it);
-        fprintf(into, "%*s  \"%s\": ", (int)indent.len, indent.data, str.data);
-        bson_value_ref val = bson_iterator_value(it);
-        switch (val.type) {
-        case bson_type_eod:
-        case bson_type_double:
-            fprintf(into, "%f,\n", val.double_);
-            break;
-        case bson_type_utf8:
-            fprintf(into, "\"%s\",\n", val.utf8.data);
-            break;
-        case bson_type_document:
-        case bson_type_array: {
-            mlib_str  i2     = mlib_str_append(indent, "  ");
-            bson_view subdoc = bson_iterator_value(it).document;
-            print_bson(into, subdoc, mlib_str_view_from(i2));
-            mlib_str_delete(i2);
-            fprintf(into, ",\n");
-            break;
-        }
-        case bson_type_undefined:
-            fprintf(into, "[undefined],\n");
-            break;
-        case bson_type_bool:
-            fprintf(into, val.bool_ ? "true,\n" : "false,\n");
-            break;
-        case bson_type_null:
-            fprintf(into, "null,\n");
-            break;
-        case bson_type_int32:
-            fprintf(into, "%d,\n", val.int32);
-            break;
-        case bson_type_int64:
-            fprintf(into, "%ld,\n", val.int64);
-            break;
-        case bson_type_timestamp:
-        case bson_type_decimal128:
-        case bson_type_maxkey:
-        case bson_type_minkey:
-        case bson_type_oid:
-        case bson_type_binary:
-        case bson_type_datetime:
-        case bson_type_regex:
-        case bson_type_dbpointer:
-        case bson_type_code:
-        case bson_type_symbol:
-        case bson_type_codewscope:
-            fprintf(into, "[[printing unimplemented for this type]],\n");
-            break;
-        }
-    }
-    fprintf(into, "%*s}", (int)indent.len, indent.data);
-}

docs/how-to/communicate.rst

@@ -46,7 +46,7 @@ The first "interesting" code will declare and initialize the default event loop:
 .. literalinclude:: communicate.example.c
   :lineno-match:
   :start-at: loop;
-  :end-at: );
+  :end-at: }
 
 .. seealso:: `amongoc_loop` and `amongoc_default_loop_init`
 
@@ -204,14 +204,11 @@ the first continuation, we use `amongoc_tie` to convert the emitter to an
 
 .. literalinclude:: communicate.example.c
   :lineno-match:
-  :start-at: fin_status
+  :start-at: amongoc_tie
   :end-at: amongoc_tie
 
 This will allow us to see the final result status of the program in
-``fin_status`` after the returned operation ``op`` completes. We pass ``NULL``
-for the `amongoc_tie::value` parameter, indicating that we do not care what the
-final result value will be (in a successful case, this would just be the
-`amongoc_nil` returned from ``after_hello``).
+``fin_status`` after the returned operation ``op`` completes.
 
 
 Start the Operation, Run the Loop, and Clean Up
@@ -243,7 +240,7 @@ Print the Final Result
 
 .. literalinclude:: communicate.example.c
   :lineno-match:
-  :start-at: is_error
+  :start-at: // Final status
   :end-before: end.
 
 Finally, we inspect the `amongoc_status` that was produced by our operation and

docs/how-to/index.rst

@@ -6,5 +6,6 @@ How-to Guides
   :caption: Guides
   :maxdepth: 2
 
+  status-handling
   communicate
   looping

docs/how-to/looping.example.c

@@ -20,7 +20,9 @@ typedef struct {
  *
  * @param state_ptr Pointer to the `state` for the program
  */
-amongoc_emitter loop_step(amongoc_box state_ptr, amongoc_status prev_status, amongoc_box prev_res) {
+amongoc_emitter loop_step(amongoc_box    state_ptr,  //
+                          amongoc_status prev_status,
+                          amongoc_box    prev_res) {
     (void)prev_res;
     (void)prev_status;
     // Print our status
@@ -60,7 +62,10 @@ int main(int argc, char const* const* argv) {
 
     // Create a default loop
     amongoc_loop loop;
-    amongoc_default_loop_init(&loop);
+    amongoc_if_error (amongoc_default_loop_init(&loop), msg) {
+        fprintf(stderr, "Error initializing event loop: %s\n", msg);
+        return 1;
+    }
 
     // Seed the initial sum
     state app_state = {.countdown = delay, .loop = &loop, .a = 0, .b = 1};
@@ -70,22 +75,19 @@ int main(int argc, char const* const* argv) {
     // Tie the final result for later, and start the program
     amongoc_status    status;
     amongoc_box       result;
-    amongoc_operation op = amongoc_tie(em, &status, &result, mlib_default_allocator);
+    amongoc_operation op = amongoc_tie(em, &status, &result);
     amongoc_start(&op);
     // Run the program within the event loop
     amongoc_default_loop_run(&loop);
     amongoc_operation_delete(op);
     amongoc_default_loop_destroy(&loop);
 
-    if (amongoc_is_error(status)) {
-        char* msg = amongoc_status_strdup_message(status);
+    amongoc_if_error (status, msg) {
         fprintf(stderr, "error: %s\n", msg);
-        free(msg);
         amongoc_box_destroy(result);
         return 2;
-    } else {
-        // Get the value returned with `amongoc_just` in `loop_step`
-        printf("Got final value: %lu\n", amongoc_box_cast(uint64_t, result));
     }
+    // Get the value returned with `amongoc_just` in `loop_step`
+    printf("Got final value: %lu\n", amongoc_box_cast(uint64_t, result));
     return 0;
 }

docs/how-to/looping.rst

@@ -196,14 +196,14 @@ program. We check for errors, either printing the error message or printing the
 final result:
 
 .. literalinclude:: looping.example.c
-  :start-at: is_error
+  :start-at: if_error (status, msg)
   :end-at: return 0;
   :lineno-match:
 
-We use `amongoc_is_error` to test the final status for an error condition. If it
-is an error, we get and print the error message to stderr, and we must destroy
-the final result box because it may contain an unspecified value related to the
-error, but we don't want to do anything with it.
+We use :c:macro:`amongoc_if_error` to test the final status for an error
+condition. If it is an error, we get and print the error message to stderr, and
+we must destroy the final result box because it may contain an unspecified value
+related to the error, but we don't want to do anything with it.
 
 In the success case, we extract the value returned in `amongoc_just` as a
 ``uint64_t`` and print it to stdout. Note that because the box returned by