Added Robustness

There are a lot of changes here:
-Fixed a lot of issues encountered during my testing
-JSON path is evaluated BEFORE making comparisons (this was the true intended behavior by @chakflying)
-Variable name changes (cosmetic)
-Added != operator
-Changed jsonQueryDescription (again)
This commit is contained in:
Matt Visnovsky 2024-06-06 18:52:33 -06:00
parent eaa935cba0
commit fdc145bffd
6 changed files with 61 additions and 78 deletions

View file

@ -600,23 +600,12 @@ class Monitor extends BeanModel {
} else if (this.type === "json-query") {
let data = res.data;
// convert data to object
if (typeof data === "string" && res.headers["content-type"] !== "application/json") {
try {
data = JSON.parse(data);
} catch (_) {
// Failed to parse as JSON, just process it as a string
}
}
const { status, response } = await evaluateJsonQuery(data, this.jsonPath, this.jsonPathOperator, this.expectedValue);
const { status, evaluation } = await evaluateJsonQuery(data, this.jsonPath, this.jsonPathOperator, this.expectedValue);
bean.status = status ? UP : DOWN;
bean.msg = `JSON query ${status ? "passes" : "does not pass"} `;
bean.msg += `comparison: ${response} ${this.jsonPathOperator} ${this.expectedValue}.`;
if (status) {
bean.msg += ", expected value is found";
bean.status = UP;
} else {
throw new Error(`${bean.msg}, but value is not equal to expected value, value was: [${evaluation}]`);
}
}
} else if (this.type === "port") {

View file

@ -44,13 +44,11 @@ class SNMPMonitorType extends MonitorType {
// We restrict querying to one OID per monitor, therefore `varbinds[0]` will always contain the value we're interested in.
const value = varbinds[0].value;
const { status, evaluation } = await evaluateJsonQuery(value, monitor.jsonPath, monitor.jsonPathOperator, monitor.expectedValue);
const { status, response } = await evaluateJsonQuery(value, monitor.jsonPath, monitor.jsonPathOperator, monitor.expectedValue);
heartbeat.status = status ? UP : DOWN;
heartbeat.msg = `SNMP value ${status ? "passes" : "does not pass"} `;
heartbeat.msg += (monitor.jsonPathOperator === "custom")
? `custom query. Query result: ${evaluation}. Expected Value: ${monitor.expectedValue}.`
: `comparison: ${value.toString()} ${monitor.jsonPathOperator} ${monitor.expectedValue}.`;
heartbeat.msg += `comparison: ${response} ${monitor.jsonPathOperator} ${monitor.expectedValue}.`;
} catch (err) {
heartbeat.status = DOWN;

View file

@ -59,7 +59,7 @@
"Keyword": "Keyword",
"Invert Keyword": "Invert Keyword",
"Expected Value": "Expected Value",
"Custom Json Query Expression": "Custom Json Query Expression",
"Json Query Expression": "Json Query Expression",
"Friendly Name": "Friendly Name",
"URL": "URL",
"Hostname or IP Address": "Hostname or IP Address",
@ -577,7 +577,7 @@
"notificationDescription": "Notifications must be assigned to a monitor to function.",
"keywordDescription": "Search keyword in plain HTML or JSON response. The search is case-sensitive.",
"invertKeywordDescription": "Look for the keyword to be absent rather than present.",
"jsonQueryDescription": "Use JSON query to parse and extract specific data from the server's JSON response. Compare the evaluated query against the expected value after converting it into a string. Refer to {0} for detailed documentation on the query language or experiment with queries using the {1}.",
"jsonQueryDescription": "Parse and extract specific data from the server's JSON response using JSON query or use \"$\" for the raw response, if not expecting JSON. The result is then compared to the expected value, as strings. See {0} for documentation and use {1} to experiment with queries.",
"backupDescription": "You can backup all monitors and notifications into a JSON file.",
"backupDescription2": "Note: history and event data is not included.",
"backupDescription3": "Sensitive data such as notification tokens are included in the export file; please store export securely.",

View file

@ -277,13 +277,13 @@
<!-- Json Query -->
<!-- For Json Query / SNMP -->
<div v-if="monitor.type === 'json-query' || monitor.type === 'snmp'" class="my-3">
<div v-if="monitor.jsonPathOperator == 'custom'" class="my-2">
<div class="my-2">
<label for="jsonPath" class="form-label mb-0">{{ $t("Json Query Expression") }}</label>
<i18n-t tag="div" class="form-text mb-2" keypath="jsonQueryDescription">
<a href="https://jsonata.org/">jsonata.org</a>
<a href="https://try.jsonata.org/">{{ $t('playground') }}</a>
</i18n-t>
<input id="jsonPath" v-model="monitor.jsonPath" type="text" class="form-control" placeholder="$.value" required>
<input id="jsonPath" v-model="monitor.jsonPath" type="text" class="form-control" placeholder="$" required>
</div>
<div class="d-flex align-items-start">
@ -294,14 +294,14 @@
<option value=">=">&gt;=</option>
<option value="<">&lt;</option>
<option value="<=">&lt;=</option>
<option value="!=">&#33;=</option>
<option value="==">==</option>
<option value="contains">contains</option>
<option value="custom">custom</option>
</select>
</div>
<div class="flex-grow-1">
<label for="expectedValue" class="form-label">{{ $t("Expected Value (Control)") }}</label>
<input v-if="monitor.jsonPathOperator !== 'contains' && monitor.jsonPathOperator !== '==' && monitor.jsonPathOperator !== 'custom'" id="expectedValue" v-model="monitor.expectedValue" type="number" class="form-control" required step=".01">
<label for="expectedValue" class="form-label">{{ $t("Expected Value") }}</label>
<input v-if="monitor.jsonPathOperator !== 'contains' && monitor.jsonPathOperator !== '=='" id="expectedValue" v-model="monitor.expectedValue" type="number" class="form-control" required step=".01">
<input v-else id="expectedValue" v-model="monitor.expectedValue" type="text" class="form-control" required>
</div>
</div>
@ -1330,10 +1330,13 @@ message HealthCheckResponse {
this.monitor.snmpVersion = "1";
}
// Set default jsonPath
if (!this.monitor.jsonPath) {
this.monitor.jsonPath = "$";
}
// Set default condition for for jsonPathOperator
if (this.monitor.type === "json-query") {
this.monitor.jsonPathOperator = "custom";
} else {
if (!this.monitor.jsonPathOperator) {
this.monitor.jsonPathOperator = "==";
}

View file

@ -398,7 +398,6 @@ function intHash(str, length = 10) {
}
exports.intHash = intHash;
async function evaluateJsonQuery(data, jsonPath, jsonPathOperator, expectedValue) {
const expected = isNaN(expectedValue) ? expectedValue.toString() : parseFloat(expectedValue);
let response;
try {
response = JSON.parse(data);
@ -406,46 +405,43 @@ async function evaluateJsonQuery(data, jsonPath, jsonPathOperator, expectedValue
catch (_a) {
response = typeof data === "number" || typeof data === "object" ? data : data.toString();
}
if (jsonPath && typeof data === "object") {
try {
response = await jsonata(jsonPath).evaluate(response);
}
catch (err) {
throw new Error(`Error evaluating JSON query: ${err.message}`);
}
}
let jsonQueryExpression;
switch (jsonPathOperator) {
case ">":
case ">=":
case "<":
case "<=":
jsonQueryExpression = `$.value ${jsonPathOperator} $.control`;
case "!=":
jsonQueryExpression = `$.value ${jsonPathOperator} $.expected`;
break;
case "==":
jsonQueryExpression = "$string($.value) = $string($.control)";
jsonQueryExpression = "$string($.value) = $string($.expected)";
break;
case "contains":
jsonQueryExpression = "$contains($string($.value), $string($.control))";
break;
case "custom":
jsonQueryExpression = jsonPath;
jsonQueryExpression = "$contains($string($.value), $string($.expected))";
break;
default:
throw new Error(`Invalid condition ${jsonPathOperator}`);
}
const expression = jsonata(jsonQueryExpression);
let evaluation;
if (jsonPathOperator === "custom") {
evaluation = await expression.evaluate(response);
}
else {
evaluation = await expression.evaluate({
value: response,
control: expectedValue
});
}
if (evaluation === undefined) {
const status = await expression.evaluate({
value: response.toString(),
expected: expectedValue.toString()
});
if (response === undefined || status === undefined) {
throw new Error("Query evaluation returned undefined. Check your query syntax and the structure of the response data.");
}
const status = (jsonPathOperator === "custom")
? evaluation.toString() === expected.toString()
: evaluation;
return {
status,
evaluation
response
};
}
exports.evaluateJsonQuery = evaluateJsonQuery;

View file

@ -654,10 +654,8 @@ export function intHash(str : string, length = 10) : number {
* @returns An object containing the status and the evaluation result.
* @throws Error if the evaluation returns undefined.
*/
export async function evaluateJsonQuery(data: any, jsonPath: string, jsonPathOperator: string, expectedValue: any): Promise<{ status: boolean; evaluation: any }> {
// Check if inputs are numeric. If not, re-parse as strings. This ensures comparisons are handled correctly.
const expected = isNaN(expectedValue) ? expectedValue.toString() : parseFloat(expectedValue);
export async function evaluateJsonQuery(data: any, jsonPath: string, jsonPathOperator: string, expectedValue: any): Promise<{ status: boolean; response: any }> {
// Attempt to parse data as JSON; if unsuccessful, handle based on data type.
let response: any;
try {
response = JSON.parse(data);
@ -665,22 +663,31 @@ export async function evaluateJsonQuery(data: any, jsonPath: string, jsonPathOpe
response = typeof data === "number" || typeof data === "object" ? data : data.toString();
}
// If a JSON path is provided, pre-evaluate the data using it.
if (jsonPath && typeof data === "object") {
try {
response = await jsonata(jsonPath).evaluate(response);
} catch (err: any) {
throw new Error(`Error evaluating JSON query: ${err.message}`);
}
}
// Perform the comparison logic using the chosen operator
// Perform the comparison logic using the chosen operator
let jsonQueryExpression;
switch (jsonPathOperator) {
case ">":
case ">=":
case "<":
case "<=":
jsonQueryExpression = `$.value ${jsonPathOperator} $.control`;
case "!=":
jsonQueryExpression = `$.value ${jsonPathOperator} $.expected`;
break;
case "==":
jsonQueryExpression = "$string($.value) = $string($.control)";
jsonQueryExpression = "$string($.value) = $string($.expected)";
break;
case "contains":
jsonQueryExpression = "$contains($string($.value), $string($.control))";
break;
case "custom":
jsonQueryExpression = jsonPath;
jsonQueryExpression = "$contains($string($.value), $string($.expected))";
break;
default:
throw new Error(`Invalid condition ${jsonPathOperator}`);
@ -688,27 +695,17 @@ export async function evaluateJsonQuery(data: any, jsonPath: string, jsonPathOpe
// Evaluate the JSON Query Expression
const expression = jsonata(jsonQueryExpression);
const status = await expression.evaluate({
value: response.toString(),
expected: expectedValue.toString()
});
let evaluation;
if (jsonPathOperator === "custom") {
evaluation = await expression.evaluate(response);
} else {
evaluation = await expression.evaluate({
value: response,
control: expectedValue
});
}
if (evaluation === undefined) {
if (response === undefined || status === undefined) {
throw new Error("Query evaluation returned undefined. Check your query syntax and the structure of the response data.");
}
const status = (jsonPathOperator === "custom")
? evaluation.toString() === expected.toString()
: evaluation;
return {
status,
evaluation
status, // The evaluation of the json query
response // The response from the server or result from initial json-query evaluation
};
}