fix(controller): expressions: fix quote() of a json object (akuity#3111)

Signed-off-by: Kent Rancourt <[email protected]>

docs/docs/35-references/10-promotion-steps.md

@@ -1300,7 +1300,7 @@ with a wide variety of external services.
 | `queryParams` | `[]object` | N | A list of query parameters to include in the request. |
 | `queryParams[].name` | `string` | Y | The name of the query parameter. |
 | `queryParams[].value` | `string` | Y | The value of the query parameter. The provided value will automatically be URL-encoded if necessary. |
-| `body` | `string` | N | The body of the request. |
+| `body` | `string` | N | The body of the request. __Note:__ As this field is a `string`, take care to utilize [`quote()`](./20-expression-language.md#quote) if the body is a valid JSON `object`. Refer to the example below of posting a message to a Slack channel. |
 | `insecureSkipTLSVerify` | `boolean` | N | Indicates whether to bypass TLS certificate verification when making the request. Setting this to `true` is highly discouraged. |
 | `timeout` | `string` | N | A string representation of the maximum time interval to wait for a request to complete. _This is the timeout for an individual HTTP request. If a request is retried, each attempt is independently subject to this timeout._ See Go's [`time` package docs](https://pkg.go.dev/time#ParseDuration) for a description of the accepted format. |
 | `successExpression` | `string` | N | An [expr-lang] expression that can evaluate the response to determine success. If this is left undefined and `failureExpression` _is_ defined, the default success criteria will be the inverse of the specified failure criteria. If both are left undefined, success is `true` when the HTTP status code is `2xx`. If `successExpression` and `failureExpression` are both defined and both evaluate to `true`, the failure takes precedence. Note that this expression should _not_ be offset by `${{` and `}}`. See examples for more details. |
@@ -1440,6 +1440,9 @@ This examples is adapted from
 [Slack's own documentation](https://api.slack.com/tutorials/tracks/posting-messages-with-curl):
 
 ```yaml
+vars:
+- name: slackChannel
+  value: C123456
 steps:
 # ...
 - uses: http
@@ -1452,8 +1455,8 @@ steps:
     - name: Content-Type
       value: application/json
     body: |
-      {
-        "channel": ${{ vars.slackChannel }},
+      ${{ quote({
+        "channel": vars.slackChannel,
         "blocks": [
           {
             "type": "section",
@@ -1463,7 +1466,7 @@ steps:
             }
           }
         ]
-      }
+      }) }}
 ```
 
 </TabItem>

internal/expressions/json_templates.go

@@ -105,7 +105,13 @@ func EvaluateTemplate(template string, env map[string]any, exprOpts ...expr.Opti
 	}
 	exprOpts = append(exprOpts, expr.Function(
 		"quote",
-		func(a ...any) (any, error) { return fmt.Sprintf(`"%v"`, a[0]), nil },
+		func(a ...any) (any, error) {
+			jsonBytes, err := json.Marshal(a[0])
+			if err != nil {
+				return nil, fmt.Errorf("error applying quote() function: %w", err)
+			}
+			return fmt.Sprintf(`"%s"`, jsonBytes), nil
+		},
 		new(func(any) string),
 	))
 	t, err := fasttemplate.NewTemplate(template, "${{", "}}")

internal/expressions/json_templates_test.go

@@ -179,13 +179,43 @@ func TestEvaluateJSONTemplate(t *testing.T) {
 			},
 		},
 		{
-			name:         "quote function forces string result",
-			jsonTemplate: `{ "AString": "${{ quote(anInt) }}" }`,
+			name:         "quote function forces null to string",
+			jsonTemplate: `{ "AString": "${{ quote(null) }}" }`,
 			assertions: func(t *testing.T, jsonOutput []byte, err error) {
 				require.NoError(t, err)
 				parsed := testStruct{}
 				require.NoError(t, json.Unmarshal(jsonOutput, &parsed))
-				require.Equal(t, fmt.Sprintf("%d", testEnv["anInt"]), parsed.AString)
+				require.Equal(t, "null", parsed.AString)
+			},
+		},
+		{
+			name:         "quote function forces bool to string",
+			jsonTemplate: `{ "AString": "${{ quote(true) }}" }`,
+			assertions: func(t *testing.T, jsonOutput []byte, err error) {
+				require.NoError(t, err)
+				parsed := testStruct{}
+				require.NoError(t, json.Unmarshal(jsonOutput, &parsed))
+				require.Equal(t, "true", parsed.AString)
+			},
+		},
+		{
+			name:         "quote function forces number to string",
+			jsonTemplate: `{ "AString": "${{ quote(42) }}" }`,
+			assertions: func(t *testing.T, jsonOutput []byte, err error) {
+				require.NoError(t, err)
+				parsed := testStruct{}
+				require.NoError(t, json.Unmarshal(jsonOutput, &parsed))
+				require.Equal(t, "42", parsed.AString)
+			},
+		},
+		{
+			name:         "quote function forces object to string",
+			jsonTemplate: `{ "AString": "${{ quote({ 'foo': 'bar' }) }}" }`,
+			assertions: func(t *testing.T, jsonOutput []byte, err error) {
+				require.NoError(t, err)
+				parsed := testStruct{}
+				require.NoError(t, json.Unmarshal(jsonOutput, &parsed))
+				require.Equal(t, `{"foo":"bar"}`, parsed.AString)
 			},
 		},
 	}