From the Queries I've been executing nothing is returned. Example of a query to print a newline per queries stored as a json array in the log line: Returns the current time in the local timezone of the Loki server. We support multiple value types which are automatically inferred from the query input. For example, for the query {job="varlogs"}|json|drop level, method="GET", with below log line, Similary, this expression can be used to drop __error__ labels as well. What are the advantages of running a power tool on 240 V vs 120 V? When using |~ and !~, Go (as in Golang) RE2 syntax regex may be used. Each line filter expression has a filter operator Looking for job perks? And a label should only appear in one of the lists specified by on and group_x. LogQL also supports aggregation, which can be used to aggregate the elements within a single vector to produce a new vector with fewer elements. In this example, log streams that have a label of app whose value is mysql and a label of name whose value is mysql-backup will be included in the query results. if a time series vector is multiplied by 2, the result is another vector in which every sample value of the original vector is multiplied by 2. I have been running Grafana Loki on my hobby machine which only has 2 core and 2 GB memory without any hiccup for over 2 years now. These filter operators are supported: Note: Unlike the label matcher regex operators, the |~ and !~ regex operators are not fully anchored. For more consistency between Loki installations, its recommended to use toDateInZone, The format string must use the exact date as defined in the golang datetime layout, Signature: toDate(fmt, str string) time.Time. You can use a match-all regex together with a stream you have for all your logs. further filters out log lines. Email update@grafana.com for help. Parser expressions parse and extract tags from log content, and these extracted tags can be used in tag filtering expressions for filtering, or for metric aggregation. Each expression can filter out, parse, or mutate log lines and their respective labels. Extracted label keys are automatically sanitized by all parsers, to follow Prometheus metric name convention. The unwrap expression is noted | unwrap label_identifier where the label identifier is the label name to use for extracting sample values. I will try. Open positions, Check out the open source projects we support The on keyword reduces the set of considered labels to a specified list. Use this function to remove given characters from the front or back of a string. regex character matches all characters, including newlines. Note: If you use Grafana Cloud, you can request modifications to this feature by opening a support ticket in the Cloud Portal. Entries for which no matching entry in the right-hand vector can be found are not part of the result. You can interpolate the value from the field with the. For example, to calculate the top 5 qps for nginx and group them by pod. The following label matching operators are supported: Note: Unlike the line filter regex expressions, the =~ and !~ regex operators are fully anchored. You can use double-quoted strings or backquotes {{.label_name}} for templates to avoid escaping special characters. The same rules that apply for Prometheus Label Selectors apply for Grafana Loki log stream selectors. Group by regex Loki - Grafana Loki - Grafana Labs Community Forums Sorry, an error occurred. This version uses group_left() to include from the right hand side in the result and returns the cost of discarded events per user, organization, and namespace: LogQL queries can be commented using the # character: With multi-line LogQL queries, the query parser can exclude whole or partial lines using #: There are multiple reasons which cause pipeline processing errors, such as: When those failures happen, Loki wont filter out those log lines. For example with cluster="namespace" the cluster is the label identifier, the operation is = and the value is namespace. Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide. (They can only contain ASCII letters and digits, as well as underscores and colons. See Unwrap examples for query examples that use the unwrap expression. There are two benefits. Grafana Loki documentation LogQL: Log query language Template functions Open source Template functions The text template format used in | line_format and | label_format support the usage of functions. We can use {app="fake-logger"} to query the applications log stream data in Grafana. The following label matching operators are supported: =: exactly equal. A predicate contains a tag identifier, operator and a value for comparing tags. By default, the system matches and, unless, and or operations with all entries in the right vector. You can wrap predicates in parentheses to force a different priority from left to right. Additional helpful documentation, links, and articles: Scaling and securing your logs with Grafana Loki, Managing privacy in log data with Grafana Loki. If we wish to match only the contents of msg=", we can use the following expression to do so. The regular expression must contain at least one named submatch (e.g. Grafana lists these variables in dropdown select boxes at the top of the dashboard to help you change the data displayed in your dashboard. If we have the following labels ip=1.1.1.1, status=200 and duration=3000(ms), we can divide duration by 1000 to get the value in seconds. Advice needed: Unwrapping parsed field. Issue #3253 grafana/loki . You can chain multiple predicates using and and or which respectively express the and and or binary operations. A label name can only appear once in each expression, which means that | label_format foo=bar,foo="new" is not allowed, but you can use two expressions to achieve the desired effect, such as | label_format foo=bar | label_format foo="new" . topk and bottomk are different from other aggregators in that a subset of the input samples, including the original labels, are returned in the result vector. Captures are matched from the line beginning or the previous set of literals, to the line end or the next set of literals. Metric queries | Grafana Loki documentation The last example will return world world. Set the data sources basic configuration options: Note: To troubleshoot configuration and other issues, check the log file located at /var/log/grafana/grafana.log on Unix systems, or in /data/log on other platforms and manual installations. Note: If you use Grafana Cloud, you can request modifications to this feature by opening a support ticket in the Cloud Portal. Will extract and rewrite the log line to only contains the query and the duration of a request. If you cant, the pattern and regexp parsers can be used for log lines with an unusual structure. The = operator after the tag name is a tag matching operator, and there are several tag matching operators supported in LogQL. All log streams that have both a label of app whose value is mysql The right side can alternatively be a template string (double quoted or backtick), for example dst="{{.status}} {{.query}}", in which case the dst label value is replaced by the result of the text/template evaluation. This means that fewer tags lead to smaller indexes, which leads to better performance, so we should always think twice before adding tags. Keep log lines that have the substring error: Discard log lines that have the substring kafka.server:type=ReplicaManager: Keep log lines that contain a substring that starts with tsdb-ops and ends with io:2003. Using basic authorization and a derived field: You must escape the dollar ($) character in YAML values because it can be used to interpolate environment variables: In this example, the Jaeger data sources uid value should match the Loki data sources datasourceUid value. See the blog: Parsing and formatting date/time in Go for more information. Subtract numbers. but only the specified pairs within the stream selector are used to determine This should be clearly stated in examples and documentation: In Grafana 7, you have the transformations tab, select "Labels to Fields . Signature: func(a interface{}, v interface{}) float64, Mulitply numbers. How can i turn no data to zero in Loki - Grafana Loki - Grafana Labs *", with below log lines. Count all the log lines within the last five minutes for the traefik namespace. Loki defines Time Durations with the same syntax as Prometheus. In this article, we will install Grafana, Loki and collect logs from . For example, to calculate the qps of nginx. Log queries | Grafana Loki documentation Like PromQL, LogQL supports a subset of built-in aggregation operators that can be used to aggregate the element of a single vector, resulting in a new vector of fewer elements but with aggregated values: The aggregation operators can either be used to aggregate over all label values or a set of distinct label values by including a without or a by clause: parameter is required when using topk and bottomk. Click on Select. You can use a debug section to see what your fields extract and how the URL is interpolated. Java emits logs as JSON. It searches the contents of the log line, Alternatively, you can use the \s (match whitespaces, including newline) in combination with \S (match not whitespace characters) to match all characters, including newlines. The duration can be placed The bool modifier must not be provided. use multiple parsers (logfmt and regexp): This is possible because the | line_format reformats the log line to become POST /api/prom/api/v1/query_range (200) 1.5s which can then be parsed with the | regexp parser. What were the most popular text editors for MS-DOS in the 1980s? and do not include the string timeout. In a chained pipeline, the result of each command is passed as the last argument of the following command. then the timeseries is returned unchanged. The = operator after the tag name is a tag matching operator, and there are several tag matching operators supported in LogQL. Between two vectors, a binary arithmetic operator is applied to each entry in the left-hand side vector and its matching element in the right-hand vector. Monitoring with Grafana, Prometheus, and Loki - Medium It takes as parameter a comma separated list of equality operations, enabling multiple operations at once. Collect and View Logs with Grafana Loki | by oleksii_y | Medium Only when using the bottomk and topk functions, we can enter the relevant arguments to the functions. Signature: replace(old string, new string, src string) string. LogQL supports a set of built-in functions. This is the same template engine as the | line_format expression, which means labels are available as variables and you can use the same list of functions. After the modification, you can normally see the relevant event information in the cluster in Dashboard, but it is recommended to replace the query statement in the panel with a record rule. Email update@grafana.com for help. *"} doesn't work for me. LogQL is Grafana Lokis PromQL-inspired query language. Which can be used to aggregate over distinct labels dimensions by including a without or by clause. ~, regular expressions with Golangs RE2 syntax can be used. Only users with the organization administrator role can add data sources. 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