* move evaluation function out of loop
* extract updateRule function
* isolate alertRule change. update returns new rule and the evaluation accepts the rule as argument
* extract retry loop into a function
* add function wide log context.
* refactor metrics + add tests + replace timeNow with schedule.clock
* TimeZonePicker: Allow specifying internal timezones to display
* Elasticsearch: Add time zone setting to Date Histogram aggregation
* rename time_zone to timeZone
* Add tests
* fix typo
* Update packages/grafana-data/src/datetime/timezones.ts
Co-authored-by: Chris Cowan <chris@chriscowan.us>
Co-authored-by: Chris Cowan <chris@chriscowan.us>
* Navigation: Remove plus button behind feature toggle
* Navigation: Add home button behind feature toggle
* Navigation: Move settings/admin to bottom section behind feature toggle
* Navigation: Refactor grafana logo to be a NavBarItem
* Navigation: Create new PluginSection and styling changes to support new sections
* Navigation: Hack to use mobile menu as a mega menu for now
* Navigation: Only render plugin section if there are items
* Navigation: mobile menu is always 100% width if toggle is off
* Navigation: Reset width back to 48 and fix broken css property
* Navigation: Create generic NavBarSection component to reduce repetition
* Navigation: Don't show sublinks for core items
* Navigation: Comments from UX review
* Navigation: Remove mobile menu hack
* Navigation: Unit tests for enrichConfigItems and other minor review comments
* Navigation: Move section logic to backend
* Navigation: Refactor alerting links out into a separate function
* Navigation: More tests for isLinkActive
* Linting...
* Navigation: Create new NavBar component for when feature toggle is enabled
* refactor goconvey in some provisioning subpackages
* fix goconvey in provisioning/datasources
* remove goconvey from notifiers subpackage
* finally resolve goconvey in dashboards subpackage
* Align range to seconds in log queries
* Use default display processor if there is none in FieldDisplayProxy
* Allow links defined in dataframe
* Remove debug log
* Fix typings for span links
* Lint go
* Fix tests
* Update tests
* Add test for the display proxy
* Streamline the fallback for diplayProcessor
* AccessControl: Create FGAC roles for orgs
Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com>
Co-authored-by: Ursula Kallio <73951760+osg-grafana@users.noreply.github.com>
* Added an option to discord notifier to use discord's webhook name (useful for customizing notifications).
* Support ngalert system with discord username toggle
* Added ngalert discord test
* Apply suggestions from code review
Co-authored-by: gotjosh <josue.abreu@gmail.com>
* Docs updated with discord username setting
* Fix api integration test
Co-authored-by: Marcus Efraimsson <marcus.efraimsson@gmail.com>
Co-authored-by: gotjosh <josue.abreu@gmail.com>
* refactor goconvey in teamguardian package
* use proper order of parameters in equality assertion
Co-authored-by: ying-jeanne <74549700+ying-jeanne@users.noreply.github.com>
Co-authored-by: ying-jeanne <74549700+ying-jeanne@users.noreply.github.com>
* Alerting: Validate contact point configuration during the migration
This minimises the chances of generating broken configuration as part of the migration. Originally, we wanted to generate it and not produce a hard stop in Grafana but this strategy has the chance to avoid delivering notifications for our users.
We now think it's better to hard stop the migration and let the user take care of resolving the configuration manually.
* Protect datasource tsdb and proxy endpoints with access control
* Add datasource query permissions to fixed admin role
Co-authored-by: Gabriel MABILLE <gamab@users.noreply.github.com>
Co-authored-by: Mitch Seaman <mjseaman@users.noreply.github.com>
* avoid duplicate allocations
* set labels
* Replace NaN in matrix with null
* Refactor and add test
* Update test
* Append response only if no error
Co-authored-by: Ryan McKinley <ryantxu@gmail.com>
* Add extra fields to OSS types to support enterprise
* Create a service account at the same time as the API key
* Use service account credentials when accessing API with APIkey
* Add GetRole to service, merge RoleDTO and Role structs
This patch merges the identical OSS and Enterprise data structures, which improves the code for two reasons:
1. Makes switching between OSS and Enterprise easier
2. Reduces the chance of incompatibilities developing between the same functions in OSS and Enterprise
* If API key is not linked to a service account, continue login as usual
* Fallback to old auth if no service account linked to key
* Add CloneUserToServiceAccount
* Adding LinkAPIKeyToServiceAccount
* Handle api key link error
* Better error messages for OSS accesscontrol
* Set an invalid user id as default
* Re-arrange field names
* ServiceAccountId is integer
* Better error messages
Co-authored-by: Hugo Häggmark <hugo.haggmark@grafana.com>
Co-authored-by: Eric Leijonmarck <eric.leijonmarck@gmail.com>
Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com>
Co-authored-by: Ieva <ieva.vasiljeva@grafana.com>
Co-authored-by: Gabriel MABILLE <gamab@users.noreply.github.com>
* update loki
* install openssl from alpine's edge repository
* extracttraceid moved to tracing package
* remove exit if warning limit is exceeded
* disable flaky libraryelements test
* context all the things
* apply feedback
* rollback some alerting changes
* rollback some alerting changes #2
* more rollbacks
* more rollbacks #2
* more rollbacks #3
* more rollbacks #4
* fix integration test
* add missing context
* add missing and remove incorrect dispatch
* Add global week start option to shared preferences
* Add default_week_start to configuration docs
* Add week start option to dashboards
* Add week start argument to tsdb time range parser
* Fix strict check issues
* Add tests for week start
* Change wording on default_week_start documentation
Co-authored-by: achatterjee-grafana <70489351+achatterjee-grafana@users.noreply.github.com>
* Update week_start column to be a nullable field
Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com>
* Update configuration to include browser option
* Update WeekStartPicker container selector
Co-authored-by: Hugo Häggmark <hugo.haggmark@grafana.com>
* Add menuShouldPortal to WeekStartPicker to remove deprecation warning
Co-authored-by: Alex Khomenko <Clarity-89@users.noreply.github.com>
* Add inputId to WeekStartPicker
* Use e2e selector on WeekStartPicker aria-label
* Simplify WeekStartPicker onChange condition
* Specify value type on WeekStartPicker weekStarts
* Remove setWeekStart side effect from reducer
* Fix updateLocale failing to reset week start
* Store week start as string to handle empty values
Co-authored-by: achatterjee-grafana <70489351+achatterjee-grafana@users.noreply.github.com>
Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com>
Co-authored-by: Hugo Häggmark <hugo.haggmark@grafana.com>
Co-authored-by: Alex Khomenko <Clarity-89@users.noreply.github.com>
* Remove Convey from dashboards
* Add context for dashboards
* Remove Convey from dashboards
* refactor tests to run setup each time
* Fix last tests
* Adjust after rebase
* Remove print statement
Co-authored-by: Serge Zaitsev <serge.zaitsev@grafana.com>
* Fix processing for table in dashboard - expolre compatible
* Add processing of histograms
* Interpolsate rate_interval in step field
* Add tests
* Fix function name
* Extract internal range and interval variables to constants
* Fix typings, refactor, simplify
* Fix constant that was missing _ms
* Alerting: Remove invalid Slack URL as we migrate notification channels
Grafana will accept any type of utf8 valid string as the Slack URL and will simply fail as we try to deliver the notification of the channel. The Alertmanager will fail to apply a configuration if the URL of the Slack Receiver is invalid.
This change takes that into account by removing the URL for the receiver as we migrate notification channels that do not pass the url validation. As we assume the notification was not being delivered to being with.
* Add a log line when we modify the channel
Co-authored-by: Yuriy Tseretyan <yuriy.tseretyan@grafana.com>
* Alerting: Fixes a bug when trying to sync broken alertmanager config
Broken alertmanager configuration has the potential to be introduced as part of a migration e.g. due to incompatible data between what grafana accepts and what the Alertmanager expects. When this happens, we expect an eventually consistent behaviour where we'll keep trying to apply the configuration until it works.
As part of change in https://github.com/grafana/grafana/pull/39237 we introduced a regression that modified this behaviour and instead tried to create a new Alertmanager for that organization everytime, which eventually ended up in a panic due to a duplicate metrics being registered.
This PR fixes that and introduces a test to catch further regressions.
* Remove disable orgs
* Prometheus: Run Explore both queries trough backend
* Refactor, simplify
* Set default values for query type selector
* Run multiple queries as one query trough backend
* Remove trailing newlines
* Pass utcOffset
* Remove trailing comma
* WIP: Implementatioon of exemplars
* add sampling for exemplars
* Refactor to use response as custom metadata
* Simplify processing of exemplars
* Update, clean up
* Refactor the way how we get available exemplars
* Simplify exemplars disabling and running on frontend
* Add tests
* Update toggle
* Remove console log
* Fix go linting
* Fix e2e test
* Trigger Build
* Compare lengts, small fix
* Remove duplicated time check
* Address feedback
* Remove redundant ! as not needed
* Update
* Add file blacklist to `grafana-cli cue gen-ts` cmd
* Add CI step checking all cuetsification is done
* Add dummy command to make the next one fail
* Generate drone bits
* Check diff output failure
* Echo list of untracked files, for failure locality
* Move git cleanness checking into script
* Blacklist of cue files is complete and correct
* Remove news panel plugin from cuetsify blacklist
* Dummy commit, check that untracked gen still fail
* Tie off remaining errors
* Re-add barchart to blacklist
* Remove file left around by earlier pipeline
* Commit generated news models.gen.ts
* Include eslint as part of cuetsified output gen
* Update pkg/cmd/grafana-cli/commands/cuetsify_command.go
Co-authored-by: Ashley Harrison <ashley.harrison@grafana.com>
* Update scripts/drone/steps/lib.star
Co-authored-by: Maria Alexandra <239999+axelavargas@users.noreply.github.com>
* Update drone.yml
* Last fix on .drone.yml
Co-authored-by: Ashley Harrison <ashley.harrison@grafana.com>
Co-authored-by: Maria Alexandra <239999+axelavargas@users.noreply.github.com>
* Encryption: Add support to encrypt/decrypt sjd
* Add datasources.Service as a proxy to datasources db operations
* Encrypt ds.SecureJsonData before calling SQLStore
* Move ds cache code into ds service
* Fix tlsmanager tests
* Fix pluginproxy tests
* Remove some securejsondata.GetEncryptedJsonData usages
* Add pluginsettings.Service as a proxy for plugin settings db operations
* Add AlertNotificationService as a proxy for alert notification db operations
* Remove some securejsondata.GetEncryptedJsonData usages
* Remove more securejsondata.GetEncryptedJsonData usages
* Fix lint errors
* Minor fixes
* Remove encryption global functions usages from ngalert
* Fix lint errors
* Minor fixes
* Minor fixes
* Remove securejsondata.DecryptedValue usage
* Refactor the refactor
* Remove securejsondata.DecryptedValue usage
* Move securejsondata to migrations package
* Move securejsondata to migrations package
* Minor fix
* Fix integration test
* Fix integration tests
* Undo undesired changes
* Fix tests
* Add context.Context into encryption methods
* Fix tests
* Fix tests
* Fix tests
* Trigger CI
* Fix test
* Add names to params of encryption service interface
* Remove bus from CacheServiceImpl
* Add logging
* Add keys to logger
Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com>
* Add missing key to logger
Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com>
* Undo changes in markdown files
* Fix formatting
* Add context to secrets service
* Rename decryptSecureJsonData to decryptSecureJsonDataFn
* Name args in GetDecryptedValueFn
* Add template back to NewAlertmanagerNotifier
* Copy GetDecryptedValueFn to ngalert
* Add logging to pluginsettings
* Fix pluginsettings test
Co-authored-by: Tania B <yalyna.ts@gmail.com>
Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com>
* Extract search users to a new service
* Fix wire provider
* Fix common_test and remove RouteRegister
* Remove old endpoints
* Fix test
* Create search filters using interfaces
* Move Enterprise filter, rename filter for filters and allow use filters with params
* Each filter has unique key
* Back activeLast30Days filter to OSS
* Fix tests
* Delete unusued param
* Move filters to searchusers service and small refactor
* Fix tests
* rename Bind to BindMiddleware
* make things private
* removed unused part of data bindings
* provide json and form binding helpers
* add example of binding migration in login api
* implement validation
* fix tests
* remove debug output
* put new bind api into macaron pacakge
* revert bind api breaking change
* refactor licenseURL function to use context and export permission evaluation fction
* remove provisioning file
* refactor licenseURL to take in a bool to avoid circular dependencies
* remove function for appending nav link, as it was only used once and move the function to create admin node
* better argument names
* create a function for permission checking
* extend permission checking when displaying server stats
* enable the use of enterprise access control actions when evaluating permissions
* import ordering
* move licensing FGAC action definitions to models package to allow access from oss
* move evaluatePermissions for routes to context serve
* change permission evaluator to take in more permissions
* move licensing FGAC actions again to appease wire
* avoid index out of bounds issue in case no children are passed in when creating server admin node
* simplify syntax for permission checking
Co-authored-by: Alex Khomenko <Clarity-89@users.noreply.github.com>
* update loading state for server stats
* linting
* more linting
* fix test
* fix a frontend test
* update "licensing.reports:read" action naming
* UI doesn't allow reading only licensing reports and not the rest of licensing info
Co-authored-by: Alex Khomenko <Clarity-89@users.noreply.github.com>
* feat: add displayname
* refactor: marshal role for fallback displayname
* refactor: moved to private heuristic function for displaynames
* refactor: display name trimspace and remove prefix
* refactor: renaming of fallbackFunction
* refactor: moved methods below struct types
* Alerting: (wip) add template funcs
* Alerting: (wip) numeric template functions
* Alerting: (wip) template functions
* Test for the "args" function
* Alerting: (wip) Documentation for template functions
* Alerting: template functions - refactor
* code review changes
* disable linter error
* Use Prometheus implementation of TemplateExpander
* Update docs/sources/alerting/unified-alerting/alerting-rules/create-grafana-managed-rule.md
Co-authored-by: achatterjee-grafana <70489351+achatterjee-grafana@users.noreply.github.com>
* change templateCaptureValue to support using template functions
* Update pkg/services/ngalert/state/template.go
Co-authored-by: gotjosh <josue.abreu@gmail.com>
* Test and documentation added for reReplaceAll template function
* complete missing functions, documentation and tests
* Use the alert instance's evaluation time for expanding the template
* strvalue graphlink and tablelink functions
* delete duplicate test
* make strvalue return an empty string
Co-authored-by: achatterjee-grafana <70489351+achatterjee-grafana@users.noreply.github.com>
Co-authored-by: gotjosh <josue.abreu@gmail.com>
Remove validation for labels to be accepted in the Alertmanager, This helps with datasources that produce non-compatible labels.
Adds an "object_matchers" to alert manager routers so we can support labels names with extended characters beyond prometheus/openmetrics. It only does this for the internal Grafana managed Alert Manager.
This requires a change to alert manager, so for now we use grafana/alertmanager which is a slight fork, with the intention of going back to upstream.
The frontend handles the migration of "matchers" -> "object_matchers" when the route is edited and saved. Once this is done, downgrades will not work old versions will not recognize the "object_matchers".
Co-authored-by: Kyle Brandt <kyle@grafana.com>
Co-authored-by: Nathan Rodman <nathanrodman@gmail.com>
* Add secrets service
* Revert accidental changes in util encryption
* Make minor changes
Move functional options to models
Revert renaming types to models
* Add context
* Minor change in GetDataKey
* Use CreateDataKeyWithDBSession in CreateDataKey
* Handle empty DEK name in DeleteDataKey
* Rename defaultProvider
* Remove secrets store service
* chore(Plugins/Admin): make the Plugins Catalog the default way to interact with plugins
* chore(defaults.ini): change the default value for `plugin_admin_enabled`
* test(Plugins): make the tests pass
* Prometheus: Run Explore both queries trough backend
* Refactor, simplify
* Set default values for query type selector
* Run multiple queries as one query trough backend
* Remove trailing newlines
* Pass utcOffset
* Remove trailing comma
* Add meta to frames only at 1 place
* Set exemplars to falsee if they are disabled
* Revert "Set exemplars to falsee if they are disabled"
This reverts commit e7b697c9f3.
* Extract search users to a new service
* Fix wire provider
* Fix common_test and remove RouteRegister
* Remove old endpoints
* Fix test
* Add indexes to dashboards and orgs tables
* Fix lint
* Add context to star and stats
* Use WithTransactionalDbSession
* Add additional ctx
* Remove convey
* Fix star handler name
* Use WithDbSession, use DispatchCtx
* Remove xorm from star
* change global flag to flagset
* update pr with comments
* replace flag.args by flagset
* fix build
* migrate the schema package to use cue 4.0
* fix the load package
* keep existing unified alert rules untouched
* move silences and other alertmanager files to the organization directory (only if it is a single organization deployment)
* assign the existing notification settings and routes to the first organization
* create default notification settings for each organization in the case of multi org deployment
* influxdb: flux: handle $__interval and $__interval_ms in alert-queries
* influxdb: flux: do not handle interval-variable in the frontend
* $__interval should be rounded
* added comment
Require guardian.New to take context.Context as first argument.
Migrates the GetDashboardAclInfoListQuery to be dispatched using context.
Ref #36734
Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com>
Co-authored-by: sam boyer <sam.boyer@grafana.com>
* PlaylistPage: removes search due to no wildcard support
* PlaylistPage: adds back search input and wildcard search support
* makes banner to appear only when playlist does not exist
* Chore: small refactor
* Chore: some code refactoring to make it readable
* fixes focus leaving input when query is cleared
* adds styling to the emptyQueryList banner
* extracts emptyQueryListBanner component to a separate file
* adds debounce to search
* use new theme for styling
* Chore: some nit fix
* fixes empty list banner showing for a second before the full list is loaded
* Fix: removes search when playlist is empty
Co-authored-by: Ash <ashharrison90@gmail.com>
Co-authored-by: Hugo Häggmark <hugo.haggmark@gmail.com>
* Add method GetAllLatestAlertmanagerConfiguration to DBStore
* add method ApplyConfig to AlertManager
* update multiorg alert manager to load all alertmanager configs at once
* Prometheus: Add running of instant queries trough backend
* Rename response, keep zero length frames
* Remove debug log
* Simplify and fix value text
* Update duplicated and redundant go test
* Update public/app/plugins/datasource/prometheus/datasource.ts
Co-authored-by: Giordano Ricci <me@giordanoricci.com>
* Refactor using model to create Promquery
* Fix the response length
Co-authored-by: Giordano Ricci <me@giordanoricci.com>
* added errors in plugin list.
* added error to details page.
* adding badge on details page.
* added some more tests.
* Renamed to disabled and will handle the scenario in the plugin catalog.
* Update public/app/features/plugins/admin/components/PluginDetailsDisabledError.tsx
Co-authored-by: Levente Balogh <balogh.levente.hu@gmail.com>
* fixing some nits
* added missing isDisabeld to the mock.
* adding tests to verify scenarios when plugin is disabled.
* fixed issue with formatting after file changed on GH.
Co-authored-by: Levente Balogh <balogh.levente.hu@gmail.com>
* Update embeds with new paths, remove deprefixing
* Add dist dashboard scuemata, in CUE
Also add tests that ensure all panel plugins with models.cue are
imported by this file, so that we can't go out of sync.
* Remove comment detritus
* Check error return
* Remove hardcoded path prefix from cli validator
* Run Explore range queries trough backend
* Remove trailing comma
* Add timeRange step alignment to backend
* Remove creation of instant query on backend as it is not supported ATM
* Remove non-related frontend changes
* Pass offset to calculate aligned range trough prom query
* Update order in query error message
* tableRefIds shouldn't contain undefined refIds
* Remove cloning of dataframes when processing
* Don't mutate response
* Remove ordering of processed frames
* Remove df because not needed
* Move legacy accesscontrol to middleware layer
* Remove bus usage for this endpoint
* Add tests for legacy accesscontrol
* Fix tests for org user and remove one more bus usage
* Added test for FolderAdmin as suggested in the review
Fix bug with engine cache not updating after data source updated, introduced in #36635.
Removes the SQL engine cache because since #36635 we already have instance caching in place using the SDK instance manager.
This also adds support for disposing cached SQL/xorm engines before a query happens to a data source that has been updated. Done by letting the SQL engine implementing the InstanceDisposer interface.
Fixes#37299
* pass url parameters through context.Context
* fix url param names without colon prefix
* change context params to vars
* replace url vars in tests using new api
* rename vars to params
* add some comments
* rename seturlvars to seturlparams
* Chore: GetDashboardQuery should be dispatched using DispatchCtx
* Fix after merge
* Changes after review
* Various fixes
* Use GetDashboardCtx function instead of GetDashboard
* Alerting: Refactor & fix unified alerting metrics structure
Fixes and refactors the metrics structure we have for the ngalert service. Now, each component has its own metric struct that includes the JUST the metrics it uses. Additionally, I have fixed the configuration metrics and added new metrics to determine if we have discovered and started all the necessary configurations of an instance.
This allows us to alert on `grafana_alerting_discovered_configurations - grafana_alerting_active_configurations != 0` to know whether an alertmanager instance did not start successfully.
* Support `role_attribute_path` for GitLab OAuth
Allow role mapping for GitLab accounts.
Example:
[auth.gitlab]
role_attribute_path = is_admin && 'Admin' || 'Viewer'
* Support `role_attribute_path` for GitLab OAuth
Allow role mapping for GitLab accounts.
Example:
[auth.gitlab]
role_attribute_path = is_admin && 'Admin' || 'Viewer'
* docs: add docs for role_attribute_path
* Apply suggestions from code review
Co-authored-by: Peter Leitzen <splattael@users.noreply.github.com>
* docs: update example
example should suggest a full configuration
* Apply suggestions from code review
Co-authored-by: Marcus Efraimsson <marcus.efraimsson@gmail.com>
* Apply suggestions from code review
Co-authored-by: Fiona Artiaga <89225282+GrafanaWriter@users.noreply.github.com>
* docs: add suggestions from tech writers
Co-authored-by: Henry Sachs <Henry.Sachs@deutschebahn.com>
Co-authored-by: Henry Sachs <henrysachs@gmail.com>
Co-authored-by: Marcus Efraimsson <marcus.efraimsson@gmail.com>
Co-authored-by: Fiona Artiaga <89225282+GrafanaWriter@users.noreply.github.com>
* OAuth: clarify role & group paths prefer id_token over userinfo api (#39066)
Co-authored-by: achatterjee-grafana <70489351+achatterjee-grafana@users.noreply.github.com>
Co-authored-by: Kevin Minehart <kmineh0151@gmail.com>
* warn on linux
* add warning for grpc plugins
* add windows support
* update go.mod
* reorganize imports
* update naming
* remove Windows logic
* simplify and add check for when UID and EUID don't match
* fix build
* tidy go.mod
* feedback
* cleanup + migrate
Adds a new setting dataproxy.row_limit that allows an operator to limit the
amount of rows being processed/accepted in response to database queries
originating from SQL data sources.
Closes#38975
Ref #39095
Co-authored-by: achatterjee-grafana <70489351+achatterjee-grafana@users.noreply.github.com>
* Introduce response_limit for datasource responses
* Fix lint
* Fix tests
* Add case where limit <= 0 - added parametrized tests
* Add max_bytes_reader.go
* Use new httpclient.MaxBytesReader instead of net/http one
* Fixes according to reviewer's comments
* Add tests for max_bytes_reader
* Add small piece in configuration.md
* Further fixes according to reviewer's comments
* Fix linting - fix test
* Alerting: Persist notification log and silences to the database
This removes the dependency of having persistent disk to run grafana alerting. Instead of regularly flushing the notification log and silences to disk we now flush the binary content of those files to the database encoded as a base64 string.
* Revert "Prometheus: add functionality to specify desired step interval in dashboards panels (#36422)"
This reverts commit ddf5b65c51.
Co-authored-by: Ivana Huckova <ivana.huckova@gmail.com>
* Revert "Explore: add functionality for supporting different step modes in prometheus (#37829)"
This reverts commit f433cfd8d9.
Co-authored-by: Ivana Huckova <ivana.huckova@gmail.com>
* Revert stepMode BE implementation from #36796
Co-authored-by: "Ivana Huckova" <ivana.huckova@gmail.com>
* Change templateCaptureValue to support using template functions
This commit changes templateCaptureValue to use float64 for the value
instead of *float64. This change means that annotations and labels can
use the float64 value with functions such as printf and avoid having to
check for nil. It also means that absent values are now printed as 0.
* Use math.NaN() instead of 0 for absent value
