5 .. This work is licensed under a Creative Commons Attribution 4.0 International License.
6 .. http://creativecommons.org/licenses/by/4.0
7 .. Copyright © 2017 AT&T Intellectual Property. All rights reserved.
9 Logging Enhancements Project
10 ==================================================
15 ONAP consists of many components and containers, and consequently writes
16 to many logfiles. The volume of logger output may be enormous,
17 especially when debugging. Large, disparate logfiles are difficult to
18 monitor and analyze, and tracing requests across many files, file
19 systems and containers is untenable without tooling.
21 The problem of decentralized logger output is addressed by analytics
22 pipelines such as \ `*Elastic
23 Stack* <https://www.elastic.co/products>`__ (ELK). Elastic Stack
24 consumes logs, indexes their contents
25 in \ `*Elasticsearch* <https://www.elastic.co/products/elasticsearch>`__,
26 and makes them accessible, queryable and navigable via a sophisticated
28 Discover* <https://www.elastic.co/guide/en/kibana/current/discover.html>`__.
29 This elevates the importance of standardization and machine-readability.
30 Logfiles can remain browsable, but output can be simplified.
32 Logger configurations in ONAP are diverse and idiosyncratic. Addressing
33 these issues will prevent costs from being externalized to consumers
34 such as analytics. It also affords the opportunity to remedy any issues
35 with the handling and propagation of contextual information such as
36 transaction identifiers (presently passed as \ **X-ECOMP-RequestID **-
37 to be\ ** X-ONAP-RequestID**). This propagation is critical to tracing
38 requests as they traverse ONAP and related systems, and is the basis for
39 many analytics functions.
41 Rationalized logger configuration and output also paves the way for
42 other high-performance logger transports, including publishing directly
43 to analytics via SYSLOG
44 (`*RFC3164* <https://www.ietf.org/rfc/rfc3164.txt>`__, \ `*RFC5425* <https://www.ietf.org/rfc/rfc5425.txt>`__, \ `*RFC5426* <https://www.ietf.org/rfc/rfc5426.txt>`__)
45 and streams, and mechanisms for durability.
47 Each change is believed to be individually beneficial:
49 1. The intention is to consolidate the required setup within this
50 project however some changes and bug fixes might have to be applied
51 in the relative component project, requiring each components'
52 co-operation on the contribution.
54 2. There is an economy of scale if everything can happen under a single
57 3. Standardization benefits all, including those who want to deviate
60 ONAP Application Logging Guidelines v1.1
61 ========================================
66 The purpose of ONAP logging is to capture information needed to operate,
67 troubleshoot and report on the performance of the ONAP platform and its
68 constituent components. Log records may be viewed and consumed directly
69 by users and systems, indexed and loaded into a datastore, and used to
70 compute metrics and generate reports.
72 The processing of a single client request will often involve multiple
73 ONAP components and/or subcomponents (interchangeably referred to as
74 application in this document). The ability to track flows across
75 components is critical to understanding ONAPs behavior and performance.
76 ONAP logging uses a universally unique RequestID value in log records to
77 track the processing of every client request through all the ONAP
78 components involved in its processing.
80 A reference configuration of \ `*Elastic
81 Stack * <https://www.elastic.co/products>`__\ can be deployed
82 using \ `*ONAP Operations
83 Manager* <https://wiki.onap.org/display/DW/ONAP+Operations+Manager+Project>`__.
85 This document gives conventions you can follow to generate conformant,
86 indexable logging output from your component.
91 ONAP prescribes conventions. The use of certain APIs and providers is
92 recommended, but they are not mandatory. Most components log
93 via \ `*EELF* <https://github.com/att/EELF>`__ or `*SLF4J* <https://www.slf4j.org/>`__ to
95 like \ `*Logback* <https://logback.qos.ch/>`__ or `*Log4j* <https://logging.apache.org/log4j/2.x/>`__.
101 EELF is the\ **Event and Error Logging Framework**, described
102 at \ `*https://github.com/att/EELF* <https://github.com/att/EELF>`__.
104 EELF abstracts your choice of logging provider, and decorates the
105 familiar Logger contracts with features like:
111 - Generated wiki documentation.
113 - Separate audit, metric, security and debug logs.
115 EELF is a facade, so logging output is configured in two ways:
117 1. By selection of a logging provider such as Logback or Log4j,
118 typically via the classpath.
120 2. By way of a provider configuration document,
121 typically \ **logback.xml** or **log4j.xml**.
122 See \ `*Providers* <https://wiki.onap.org/display/DW/ONAP+Application+Logging+Guidelines+v1.1#ONAPApplicationLoggingGuidelinesv1.1-Providers>`__.
128 `*SLF4J* <https://www.slf4j.org/>`__ is a logging facade, and a humble
129 masterpiece. It combines what's common to all major, modern Java logging
130 providers into a single interface. This decouples the caller from the
131 provider, and encourages the use of what's universal, familiar and
134 EELF also logs via SLF4J's abstractions.
140 Logging providers are normally enabled by their presence in the
141 classpath. This means the decision may have been made for you, in some
142 cases implicitly by dependencies. If you have a strong preference then
143 you can change providers, but since the implementation is typically
144 abstracted behind EELF or SLF4J, it may not be worth the effort.
150 Logback is the most commonly used provider. It is generally configured
151 by an XML document named \ **logback.xml**.
152 See \ `*Configuration* <https://wiki.onap.org/display/DW/ONAP+Application+Logging+Guidelines+v1.1#ONAPApplicationLoggingGuidelinesv1.1-Configuration>`__.
158 Log4j 2.X is somewhat less common than Logback, but equivalent. It is
159 generally configured by an XML document
160 named \ **log4j.xml**. See \ `*Configuration* <https://wiki.onap.org/display/DW/ONAP+Application+Logging+Guidelines+v1.1#ONAPApplicationLoggingGuidelinesv1.1-Configuration>`__.
166 Avoid, since 1.X is EOL, and since it does not support escaping, so its
168 machine-readable. See \ `*https://logging.apache.org/log4j/1.2/* <https://logging.apache.org/log4j/1.2/>`__.
170 This affects existing OpenDaylight-based components like SDNC and APPC,
171 since ODL releases prior
172 to \ `*Carbon* <https://www.opendaylight.org/what-we-do/current-release>`__ bundle
173 Log4j 1.X, and make it difficult to replace. The \ `*Common Controller
175 Project* <https://wiki.onap.org/display/DW/Common+Controller+SDK+Project>`__ project
176 targets ODL Carbon, so the problem should resolve in time.
181 The purpose of logging is to capture diagnostic information.
183 An important aspect of this is analytics, which requires tracing of
184 requests between components. In a large, distributed system such as ONAP
185 this is critical to understanding behavior and performance.
187 Messages, Levels, Components and Categories
188 --------------------------------------------
190 It isn't the aim of this document to reiterate the basics, so advice
193 - Use a logger. Consider using EELF.
195 - Write log messages in English.
197 - Write meaningful messages. Consider what will be useful to consumers
200 - Use errorcodes to characterise exceptions.
202 - Log at the appropriate level. Be aware of the volume of logs that
205 - Log in a machine-readable format. See Conventions.
207 - Log for analytics as well as troubleshooting.
209 Others have written extensively on this:
211 - `*http://www.masterzen.fr/2013/01/13/the-10-commandments-of-logging/* <http://www.masterzen.fr/2013/01/13/the-10-commandments-of-logging/>`__
213 - `*https://www.loggly.com/blog/how-to-write-effective-logs-for-remote-logging/* <https://www.loggly.com/blog/how-to-write-effective-logs-for-remote-logging/>`__
220 **TODO: more on the importance of transaction ID propagation.**
226 A Mapped Diagnostic Context (MDC) allows an arbitrary string-valued
227 attribute to be attached to a Java thread. The MDC's value is then
228 emitted with each log message. The set of MDCs associated with a log
229 message is serialized as unordered name-value pairs (see `*Text
230 Output* <https://wiki.onap.org/display/DW/ONAP+Application+Logging+Guidelines+v1.1#ONAPApplicationLoggingGuidelinesv1.1-TextOutput>`__).
232 A good discussion of MDCs can be found
233 at \ `*https://logback.qos.ch/manual/mdc.html* <https://logback.qos.ch/manual/mdc.html>`__.
237 - Must be set as early in invocation as possible.
239 - Must be unset on exit.
246 +------+-------------------------------------------------------------------------------------+
247 | 1 | import java.util.UUID; |
249 | 2 | import org.slf4j.Logger; |
251 | 3 | import org.slf4j.LoggerFactory; |
253 | 4 | import org.slf4j.MDC; |
257 | 6 | final Logger logger = LoggerFactory.getLogger(this.getClass()); |
259 | 7 | MDC.put("SomeUUID", UUID.randomUUID().toString()); |
263 | 9 | logger.info("This message will have a UUID-valued 'SomeUUID' MDC attached."); |
271 | 13 | MDC.clear(); |
274 +------+-------------------------------------------------------------------------------------+
276 EELF doesn't directly support MDCs, but SLF4J will receive any MDC that
277 is set (where **com.att.eelf.configuration.SLF4jWrapper** is the
278 configured EELF provider):
280 +------+-------------------------------------------------------------------------------------+
281 | 1 | import java.util.UUID; |
283 | 2 | import org.slf4j.Logger; |
285 | 3 | import org.slf4j.LoggerFactory; |
287 | 4 | import org.slf4j.MDC; |
289 | 5 | import com.att.eelf.configuration.EELFLogger; |
291 | 6 | import com.att.eelf.configuration.EELFManager; |
295 | 8 | final EELFLogger logger = EELFManager.getInstance().getLogger(this.getClass()); |
297 | 9 | MDC.put("SomeUUID", UUID.randomUUID().toString()); |
301 | 11 | logger.info("This message will have a UUID-valued 'SomeUUID' MDC attached."); |
309 | 15 | MDC.clear(); |
312 +------+-------------------------------------------------------------------------------------+
317 Output of MDCs must ensure that:
319 - All reported MDCs are logged with both name AND value. Logging output
320 should not treat any MDCs as special.
322 - All MDC names and values are escaped.
324 Escaping in Logback configuration can be achieved with:
326 +-----+------------------------------------------------------------------+
327 | 1 | %replace(%replace(%mdc){'\\t','\\\\\\\\t'}){'\\n','\\\\\\\\n'} |
328 +-----+------------------------------------------------------------------+
333 This is often referred to by other names, including "Transaction ID",
334 and one of several (pre-standardization) REST header names
335 including \ **X-ECOMP-RequestID** and **X-ONAP-RequestID**.
337 ONAP logging uses a universally unique "**RequestID"** value in log
338 records to track the processing of each client request across all the
339 ONAP components involved in its processing.
343 - Is logged as a \ **RequestID** MDC.
345 - Is propagated between components in REST calls as
346 an \ **X-TransactionID** HTTP header.
348 Receiving the \ **X-TransactionID** will vary by component according to
349 APIs and frameworks. In general:
351 +-----+--------------------------------------------------------------------------+
352 | 1 | import javax.ws.rs.core.HttpHeaders; |
356 | 3 | final HttpHeaders headers = ...; |
360 | 5 | String txId = headers.getRequestHeaders().getFirst("X-TransactionID"); |
362 | 6 | if (StringUtils.isBlank(txId)) { |
364 | 7 | txId = UUID.randomUUID().toString(); |
368 | 9 | MDC.put("RequestID", txID); |
369 +-----+--------------------------------------------------------------------------+
371 Setting the \ **X-TransactionID** likewise will vary. For example:
373 +-----+---------------------------------------------------+
374 | 1 | final String txID = MDC.get("RequestID"); |
376 | 2 | HttpURLConnection cx = ...; |
380 | 4 | cx.setRequestProperty("X-TransactionID", txID); |
381 +-----+---------------------------------------------------+
386 **InvocationID** is similar to \ **RequestID**, but
387 where \ **RequestID** correlates records relating a single, top-level
388 invocation of ONAP as it traverses many
389 systems, \ **InvocationID** correlates log entries relating to a single
390 invocation of a single component. Typically this means via REST, but in
391 certain cases an \ **InvocationID** may be allocated without a new
392 invocation, e.g. when a request is retried.
394 **RequestID** and** InvocationID** allow an execution graph to be
395 derived. This requires that:
397 - The relationship between \ **RequestID** and **InvocationID** is
400 - The relationship between caller and recipient is reported for each
403 The proposed approach is that:
407 - Issue a new, unique \ **InvocationID** UUID for each downstream
410 - Log the new \ **InvocationID**, indicating the intent to invoke:
412 - With Markers \ **INVOKE**, and \ **SYNCHRONOUS** if the
413 invocation is synchronous.
415 - With their own \ **InvocationID** still set as an MDC.
417 - Pass the \ **InvocationID** as an \ **X-InvocationID** REST
420 - Invoked components:
422 - Retrieve the \ **InvocationID** from REST headers upon invocation,
423 or generate a UUID default.
425 - Set the \ **InvocationID** MDC.
427 - Write a log entry with the Marker \ **ENTRY**. (In EELF this will
428 be to the AUDIT log).
430 - Act as per Callers in all downstream requests.
432 - Write a log entry with the Marker \ **EXIT** upon return. (In EELF
433 this will be to the METRIC log).
435 - Unset all MDCs on exit.
437 That seems onerous, but:
439 - It's only a few calls.
441 - It can be largely abstracted in the case of EELF logging.
448 Other MDCs are logged in a wide range of contexts.
450 Certain MDCs and their semantics may be specific to EELF log types.
452 **TODO: cross-reference EELF output to v1 doc.**
454 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
455 | **ID** | **MDC** | **Description** | **Required** | **EELF Audit** | **EELF Metric** | **EELF Error** | **EELF Debug** |
456 +==========+=======================+================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================+================+==================+===================+==================+==================+
457 | 1 | BeginTimestamp | Date-time that processing activities being logged begins. The value should be represented in UTC and formatted per ISO 8601, such as œ2015-06-03T13:21:58+00:00
\9d. The time should be shown with the maximum resolution available to the logging component (e.g., milliseconds, microseconds) by including the appropriate number of decimal digits. For example, when millisecond precision is available, the date-time value would be presented as, as œ2015-06-03T13:21:58.340+00:00
\9d. | Y | | | | |
458 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
459 | 2 | EndTimestamp | Date-time that processing for the request or event being logged ends. Formatting rules are the same as for the BeginTimestamp field above. | Y | | | | |
461 | | | In the case of a request that merely logs an event and has not subsequent processing, the EndTimestamp value may equal the BeginTimestamp value. | | | | | |
462 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
463 | 3 | ElapsedTime | This field contains the elapsed time to complete processing of an API call or transaction request (e.g., processing of a message that was received). This value should be the difference between. EndTimestamp and BeginTimestamp fields and must be expressed in milliseconds. | Y | | | | |
464 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
465 | 4 | ServiceInstanceID | This field is optional and should only be included if the information is readily available to the logging component. | | | | | |
467 | | | | Transaction requests that create or operate on a particular instance of a service/resource can | | | | | |
468 | | | | identify/reference it via a unique œserviceInstanceID
\9d value. This value can be used as a primary key for | | | | | |
469 | | | | obtaining or updating additional detailed data about that specific service instance from the inventory | | | | | |
470 | | | | (e.g., AAI). In other words: | | | | | |
472 | | | - In the case of processing/logging a transaction request for creating a new service instance, the serviceInstanceID value is determined by either a) the MSO client and passed to MSO or b) by MSO itself upon receipt of a such a request. | | | | | |
474 | | | - In other cases, the serviceInstanceID value can be used to reference a specific instance of a service as would happen in a œMACD
\9d-type request. | | | | | |
476 | | | - ServiceInstanceID is associated with a requestID in log records to facilitate tracing its processing over multiple requests and for a specific service instance. Its value may be left œempty
\9d in subsequent record to the 1 st record where a requestID value is associated with the serviceInstanceID value. | | | | | |
478 | | | NOTE: AAI wont have a serviceInstanceUUID for every service instance. For example, no serviceInstanceUUID is available when the request is coming from an application that may import inventory data. | | | | | |
479 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
480 | 5 | VirtualServerName | Physical/virtual server name. Optional: empty if determined that its value can be added by the agent that collects the log files collecting. | | | | | |
481 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
482 | 6 | ServiceName | For Audit log records that capture API requests, this field contains the name of the API invoked at the component creating the record (e.g., Layer3ServiceActivateRequest). | Y | | | | |
484 | | | For Audit log records that capture processing as a result of receipt of a message, this field should contain the name of the module that processes the message. | | | | | |
485 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
486 | 7 | PartnerName | This field contains the name of the client application user agent or user invoking the API if known. | Y | | | | |
487 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
488 | 8 | StatusCode | This field indicates the high level status of the request. It must have the value COMPLETE when the request is successful and ERROR when there is a failure. | Y | | | | |
489 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
490 | 9 | ResponseCode | This field contains application-specific error codes. For consistency, common error categorizations should be used. | | | | | |
491 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
492 | 10 | ResponseDescription | This field contains a human readable description of the \ **ResponseCode**. | | | | | 11 |
493 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
494 | 11 | InstanceUUID | If known, this field contains a universally unique identifier used to differentiate between multiple instances of the same (named) log writing service/application. Its value is set at instance creation time (and read by it, e.g., at start/initialization time from the environment). This value should be picked up by the component instance from its configuration file and subsequently used to enable differentiation of log records created by multiple, locally load balanced ONAP component or subcomponent instances that are otherwise identically configured. | | | | | |
495 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
496 | 12 | Severity | Optional: 0, 1, 2, 3 see \ `*Nagios* <https://en.wikipedia.org/wiki/Nagios>`__ monitoring/alerting for specifics/details. | | | | | |
497 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
498 | 13 | TargetEntity | It contains the name of the ONAP component or sub-component, or external entity, at which the operation activities captured in this metrics log record is invoked. | Y | | | | |
499 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
500 | 14 | TargetServiceName | It contains the name of the API or operation activities invoked at the TargetEntity. | Y | | | | |
501 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
502 | 15 | Server | This field contains the Virtual Machine (VM) Fully Qualified Domain Name (FQDN) if the server is virtualized. Otherwise, it contains the host name of the logging component. | Y | | | | |
503 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
504 | 16 | ServerIPAddress | This field contains the logging component host servers IP address if known (e.g. Jetty containers listening IP address). Otherwise it is empty. | | | | | |
505 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
506 | 17 | ServerFQDN | Unclear, but possibly duplicating one or both of \ **Server** and **ServerIPAddress**. | | | | | |
507 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
508 | 18 | ClientIPAddress | This field contains the requesting remote client applications IP address if known. Otherwise this field can be empty. | | | | | |
509 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
510 | 19 | ProcessKey | This field can be used to capture the flow of a transaction through the system by indicating the components and operations involved in processing. If present, it can be denoted by a comma separated list of components and applications. | | | | | |
511 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
512 | 20 | RemoteHost | Unknown. | | | | | |
513 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
514 | 21 | AlertSeverity | Unknown. | | | | | |
515 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
516 | 22 | TargetVirtualEntity | Unknown | | | | | |
517 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
518 | 23 | ClassName | Defunct. Doesn't require an MDC. | | | | | |
519 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
520 | 24 | ThreadID | Defunct. Doesn't require an MDC. | | | | | |
521 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
522 | 25 | CustomField1 | (Defunct now that MDCs are serialized as NVPs.) | | | | | |
523 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
524 | 26 | CustomField2 | (Defunct now that MDCs are serialized as NVPs.) | | | | | |
525 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
526 | 27 | CustomField3 | (Defunct now that MDCs are serialized as NVPs.) | | | | | |
527 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
528 | 28 | CustomField4 | (Defunct now that MDCs are serialized as NVPs.) | | | | | |
529 +----------+-----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------+------------------+-------------------+------------------+------------------+
540 +-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
541 | root@ip-172-31-93-160:/dockerdata-nfs/onap/sdc/logs/SDC/SDC-BE# tail -f audit.log |
543 | 2017-09-07T18:04:03.679Z\|\|\|\|\|qtp1013423070-72297\|\|ASDC\|SDC-BE\|\|\|\|\|\|\|N/A\|INFO\|\|\|\|10.42.88.30\|\|o.o.s.v.r.s.VendorLicenseModelsImpl\|\|ActivityType=<audit>, Desc=< --Audit-- Create VLM. VLM Name: lm4> |
544 +-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
546 **TODO: this is the earlier output format. Let's find an example which matches the latest line format.**
551 Markers differ from MDCs in two important ways:
553 1. They have a name, but no value. They are a tag.
555 2. Their scope is limited to logger calls which specifically reference
557 not \ `*ThreadLocal* <https://docs.oracle.com/javase/8/docs/api/java/lang/ThreadLocal.html>`__.
566 +-----+-----------------------------------------------------------------------+
567 | 1 | import org.slf4j.Logger; |
569 | 2 | import org.slf4j.LoggerFactory; |
571 | 3 | import org.slf4j.Marker; |
573 | 4 | import org.slf4j.MarkerFactory; |
577 | 6 | final Logger logger = LoggerFactory.getLogger(this.getClass()); |
579 | 7 | final Marker marker = MarkerFactory.getMarker("MY\_MARKER"); |
581 | 8 | logger.warn(marker, "This warning has a 'MY\_MARKER' annotation."); |
582 +-----+-----------------------------------------------------------------------+
584 EELF does not allow Markers to be set directly. See notes on
585 the \ **InvocationID** MDC.
590 Marker names also need to be escaped, though they're much less likely to
591 contain problematic characters than MDC values.
593 Escaping in Logback configuration can be achieved with:
595 +-----+---------------------------------------------------------------------+
596 | 1 | %replace(%replace(%marker){'\\t','\\\\\\\\t'}){'\\n','\\\\\\\\n'} |
597 +-----+---------------------------------------------------------------------+
602 This should be reported as early in invocation as possible, immediately
603 after setting the \ **RequestID** and **InvocationID** MDCs.
605 It can be automatically set by EELF, and written to the AUDIT log.
607 It must be manually set otherwise.
625 +-----+------------------------------------------------------------------------+
626 | 1 | public static final Marker ENTRY = MarkerFactory.getMarker("ENTRY"); |
630 | 3 | final Logger logger = LoggerFactory.getLogger(this.getClass()); |
632 | 4 | logger.debug(ENTRY, "Entering."); |
633 +-----+------------------------------------------------------------------------+
638 This should be reported as late in invocation as possible, immediately
639 before unsetting the \ **RequestID** and **InvocationID** MDCs.
641 It can be automatically reported by EELF, and written to the METRIC
644 It must be manually set otherwise.
662 +-----+----------------------------------------------------------------------+
663 | 1 | public static final Marker EXIT = MarkerFactory.getMarker("EXIT"); |
667 | 3 | final Logger logger = LoggerFactory.getLogger(this.getClass()); |
669 | 4 | logger.debug(EXIT, "Exiting."); |
670 +-----+----------------------------------------------------------------------+
675 This should be reported by the caller of another ONAP component via
676 REST, including a newly allocated \ **InvocationID**, which will be
677 passed to the caller.
685 +------+--------------------------------------------------------------------------+
686 | 1 | public static final Marker INVOKE = MarkerFactory.getMarker("INVOKE"); |
692 | 4 | // Generate and report invocation ID. |
696 | 6 | final String invocationID = UUID.randomUUID().toString(); |
698 | 7 | MDC.put(MDC\_INVOCATION\_ID, invocationID); |
702 | 9 | logger.debug(INVOKE\_SYNCHRONOUS, "Invoking synchronously ... "); |
708 | 12 | MDC.remove(MDC\_INVOCATION\_ID); |
714 | 15 | // Pass invocationID as HTTP X-InvocationID header. |
718 | 17 | callDownstreamSystem(invocationID, ... ); |
719 +------+--------------------------------------------------------------------------+
721 **TODO: EELF, without changing published APIs.**
724 ------------------------
726 This should accompany \ **INVOKE** when the invocation is synchronous.
734 +------+-------------------------------------------------------------------------+
735 | 1 | public static final Marker INVOKE\_SYNCHRONOUS; |
739 | 3 | INVOKE\_SYNCHRONOUS = MarkerFactory.getMarker("INVOKE"); |
741 | 4 | INVOKE\_SYNCHRONOUS.add(MarkerFactory.getMarker("SYNCHRONOUS")); |
749 | 8 | // Generate and report invocation ID. |
753 | 10 | final String invocationID = UUID.randomUUID().toString(); |
755 | 11 | MDC.put(MDC\_INVOCATION\_ID, invocationID); |
759 | 13 | logger.debug(INVOKE\_SYNCHRONOUS, "Invoking synchronously ... "); |
765 | 16 | MDC.remove(MDC\_INVOCATION\_ID); |
771 | 19 | // Pass invocationID as HTTP X-InvocationID header. |
775 | 21 | callDownstreamSystem(invocationID, ... ); |
776 +------+-------------------------------------------------------------------------+
778 **TODO: EELF, without changing published APIs.**
783 Errorcodes are reported as MDCs.
785 Exceptions should be accompanied by an errrorcode. Typically this is
786 achieved by incorporating errorcodes into your exception hierarchy and
787 error handling. ONAP components generally do not share this kind of
788 code, though EELF defines a marker interface (meaning it has no
789 methods) \ **EELFResolvableErrorEnum**.
791 A common convention is for errorcodes to have two components:
793 1. A \ **prefix**, which identifies the origin of the error.
795 2. A \ **suffix**, which identifies the kind of error.
797 Suffixes may be numeric or text. They may also be common to more than
802 +-----+-------------------------------+
803 | 1 | COMPONENT\_X.STORAGE\_ERROR |
804 +-----+-------------------------------+
809 Several considerations:
811 1. Logs should be human-readable (within reason).
813 2. Shipper and indexing performance and durability depends on logs that
814 can be parsed quickly and reliably.
816 3. Consistency means fewer shipping and indexing rules are required.
822 ONAP needs to strike a balance between human-readable and
823 machine-readable logs. This means:
825 - The use of tab (**\\t**) as a delimiter.
827 - Escaping all messages, exceptions, MDC values, Markers, etc. to
828 replace tabs in their content.
830 - Escaping all newlines with \ **\\n** so that each entry is on one
833 In logback, this looks like:
835 +-----+-------------------------------------------------------------------------------+
836 | 1 | <property name="defaultPattern" value="%nopexception%logger |
838 | 2 | \\t%date{yyyy-MM-dd'T'HH:mm:ss.SSSXXX,UTC} |
842 | 4 | \\t%replace(%replace(%message){'\\t','\\\\\\\\t'}){'\\n','\\\\\\\\n'} |
844 | 5 | \\t%replace(%replace(%mdc){'\\t','\\\\\\\\t'}){'\\n','\\\\\\\\n'} |
846 | 6 | \\t%replace(%replace(%rootException){'\\t','\\\\\\\\t'}){'\\n','\\\\\\\\n'} |
848 | 7 | \\t%replace(%replace(%marker){'\\t','\\\\\\\\t'}){'\\n','\\\\\\\\n'} |
853 +-----+-------------------------------------------------------------------------------+
855 The output of which, with MDCs, a Marker and a nested exception, with newlines added for readability looks like:
857 TODO: remove tab below
859 +------+-----------------------------------------------------------------------------------------------------------------------------+
860 | 1 | org.onap.example.component1.subcomponent1.LogbackTest |
862 | 2 | \\t2017-08-06T16:09:03.594Z |
866 | 4 | \\tHere's an error, that's usually bad |
868 | 5 | \\tkey1=value1, key2=value2 with space, key5=value5"with"quotes, key3=value3\\nwith\\nnewlines, key4=value4\\twith\\ttabs |
870 | 6 | \\tjava.lang.RuntimeException: Here's Johnny |
872 | 7 | \\n\\tat org.onap.example.component1.subcomponent1.LogbackTest.main(LogbackTest.java:24) |
874 | 8 | \\nWrapped by: java.lang.RuntimeException: Little pigs, little pigs, let me come in |
876 | 9 | \\n\\tat org.onap.example.component1.subcomponent1.LogbackTest.main(LogbackTest.java:27) |
881 +------+-----------------------------------------------------------------------------------------------------------------------------+
883 Default Logstash indexing rules understand output in this format.
889 For Log4j 1.X output, since escaping is not supported, the best
890 alternative is to emit logs in XML format.
892 There may be other instances where XML (or JSON) output may be
893 desirable. Default indexing rules support
895 Default Logstash indexing rules understand the XML output of \ `*Log4J's
896 XMLLayout* <https://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/xml/XMLLayout.html>`__.
901 Standardization of output locations makes logs easier to locate and ship
904 Logfiles should default to beneath \ **/var/log**, and
905 beneath \ **/var/log/ONAP** in the case of core ONAP components:
907 +-----+-----------------------------------------------------+
908 | 1 | /var/log/ONAP/<component>[/<subcomponent>]/\*.log |
909 +-----+-----------------------------------------------------+
914 Logging providers should be configured by file. Files should be at a
915 predictable, static location, so that they can be written by deployment
916 automation. Ideally this should be under \ **/etc/ONAP**, but compliance
922 All logger provider configuration document locations namespaced by
923 component and (if applicable) subcomponent by default:
925 +-----+---------------------------------------------------------+
926 | 1 | /etc/onap/<component>[/<subcomponent>]/<provider>.xml |
927 +-----+---------------------------------------------------------+
929 Where \ **<provider>.xml**, will typically be one of:
940 Logger providers should reconfigure themselves automatically when their
941 configuration file is rewritten. All major providers should support
944 The default interval is 10s.
949 The location of the configuration file MAY be overrideable, for example
950 by an environment variable, but this is left for individual components
956 Configuration archetypes can be found in the ONAP codebase. Choose
957 according to your provider, and whether you're logging via EELF. Efforts
958 to standardize them are underway, so the ones you should be looking for
959 are where pipe (\|) is used as a separator. (Previously it was "\|").
964 Logfiles are often large. Logging providers allow retention policies to
967 Retention has to balance:
969 - The need to index logs before they're removed.
971 - The need to retain logs for other (including regulatory) purposes.
973 Defaults are subject to change. Currently they are:
975 1. Files <= 50MB before rollover.
977 2. Files retain for 30 days.
979 3. Total files capped at 10GB.
981 In Logback configuration XML:
983 +------+-------------------------------------------------------------------------------------------------------------+
984 | 1 | <appender name="file" class="ch.qos.logback.core.rolling.RollingFileAppender"> |
986 | 2 | <file>${outputDirectory}/${outputFilename}.log</file> |
988 | 3 | <rollingPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy"> |
990 | 4 | <fileNamePattern>${outputDirectory}/${outputFilename}.%d{yyyy-MM-dd}.%i.log.zip</fileNamePattern> |
992 | 5 | <maxFileSize>50MB</maxFileSize> |
994 | 6 | <maxHistory>30</maxHistory> |
996 | 7 | <totalSizeCap>10GB</totalSizeCap> |
998 | 8 | </rollingPolicy> |
1002 | 10 | <!-- ... --> |
1006 | 12 | </appender> |
1007 +------+-------------------------------------------------------------------------------------------------------------+
1012 EELF guidelines stipulate that an application should output log records
1013 to four separate files:
1023 This applies only to EELF logging. Components which log directly to a
1024 provider may choose to emit the same set of logs, but most do not.
1029 An audit log is required for EELF-enabled components, and provides a
1030 summary view of the processing of a (e.g., transaction) request within
1031 an application. It captures activity requests that are received by an
1032 ONAP component, and includes such information as the time the activity
1033 is initiated, then it finishes, and the API that is invoked at the
1036 Audit log records are intended to capture the high level view of
1037 activity within an ONAP component. Specifically, an API request handled
1038 by an ONAP component is reflected in a single Audit log record that
1039 captures the time the request was received, the time that processing was
1040 completed, as well as other information about the API request (e.g., API
1041 name, on whose behalf it was invoked, etc).
1046 A metric log is required for EELF-enabled components, and provides a
1047 more detailed view into the processing of a transaction within an
1048 application. It captures the beginning and ending of activities needed
1049 to complete it. These can include calls to or interactions with other
1050 ONAP or non-ONAP entities.
1052 Suboperations invoked as part of the processing of the API request are
1053 logged in the Metrics log. For example, when a call is made to another
1054 ONAP component or external (i.e., non-ONAP) entity, a Metrics log record
1055 captures that call. In such a case, the Metrics log record indicates
1056 (among other things) the time the call is made, when it returns, the
1057 entity that is called, and the API invoked on that entity. The Metrics
1058 log record contain the same RequestID as the Audit log record so the two
1061 Note that a single request may result in multiple Audit log records at
1062 an ONAP component and may result in multiple Metrics log records
1063 generated by the component when multiple suboperations are required to
1064 satisfy the API request captured in the Audit log record.
1069 An error log is required for EELF-enabled components, and is intended to
1070 capture info, warn, error and fatal conditions sensed (œexception
1071 handled
\9d) by the software components.
1076 A debug log is optional for EELF-enabled components, and is intended to
1077 capture whatever data may be needed to debug and correct abnormal
1078 conditions of the application.
1083 Console logging may also be present, and is intended to capture
1084 system/infrastructure records. That is stdout and stderr assigned to a
1085 single œengine.out file in a directory configurable (e.g. as an
1086 environment/shell variable) by operations personnel.
1088 New ONAP Component Checklist
1089 ============================
1091 By following a few simple rules:
1093 - Your component's output will be indexed automatically.
1095 - Analytics will be able to trace invocation through your component.
1097 Obligations fall into two categories:
1099 1. Conventions regarding configuration, line format and output.
1101 2. Ensuring the propagation of contextual information.
1105 1. Choose a Logging provider and/or EELF. Decisions, decisions.
1107 2. Create a configuration file based on an existing
1108 archetype. See \ `*Configuration* <https://wiki.onap.org/display/DW/ONAP+Application+Logging+Guidelines+v1.1#ONAPApplicationLoggingGuidelinesv1.1-Configuration>`__.
1110 3. Read your configuration file when your components initialize logging.
1112 4. Write logs to a standard location so that they can be shipped by
1113 Filebeat for indexing. See \ `*Output
1114 Location* <https://wiki.onap.org/display/DW/ONAP+Application+Logging+Guidelines+v1.1#ONAPApplicationLoggingGuidelinesv1.1-OutputLocation>`__.
1116 5. Report transaction state:
1118 a. Retrieve, default and propagate \ **RequestID**. See \ `*MDC -
1119 RequestID* <https://wiki.onap.org/display/DW/ONAP+Application+Logging+Guidelines+v1.1#ONAPApplicationLoggingGuidelinesv1.1-MDC-RequestID>`__.
1121 b. At each invocation of one ONAP component by another:
1123 i. Initialize and propagate \ **InvocationID**. See \ `*MDC -
1125 ID* <https://wiki.onap.org/display/DW/ONAP+Application+Logging+Guidelines+v1.1#ONAPApplicationLoggingGuidelinesv1.1-MDC-InvocationID>`__.
1127 ii. Report \ **INVOKE** and **SYNCHRONOUS** markers in caller.
1129 iii. Report \ **ENTRY** and **EXIT** markers in recipient.
1131 6. Write useful logs!
Code Review / logging-analytics.git / blob