package
0.13.0
Repository: https://github.com/tencentblueking/influxdb.git
Documentation: pkg.go.dev

# README

Line Protocol

The line protocol is a text based format for writing points to InfluxDB. Each line defines a single point. Multiple lines must be separated by the newline character \n. The format of the line consists of three parts:

[key] [fields] [timestamp]

Each section is separated by spaces. The minimum required point consists of a measurement name and at least one field. Points without a specified timestamp will be written using the server's local timestamp. Timestamps are assumed to be in nanoseconds unless a precision value is passed in the query string.

Key

The key is the measurement name and any optional tags separated by commas. Measurement names, tag keys, and tag values must escape any spaces or commas using a backslash (\). For example: \ and \,. All tag values are stored as strings and should not be surrounded in quotes.

Tags should be sorted by key before being sent for best performance. The sort should match that from the Go bytes.Compare function (http://golang.org/pkg/bytes/#Compare).

Examples

# measurement only
cpu

# measurement and tags
cpu,host=serverA,region=us-west

# measurement with commas
cpu\,01,host=serverA,region=us-west

# tag value with spaces
cpu,host=server\ A,region=us\ west

Fields

Fields are key-value metrics associated with the measurement. Every line must have at least one field. Multiple fields must be separated with commas and not spaces.

Field keys are always strings and follow the same syntactical rules as described above for tag keys and values. Field values can be one of four types. The first value written for a given field on a given measurement defines the type of that field for all series under that measurement.

  • integer - Numeric values that do not include a decimal and are followed by a trailing i when inserted (e.g. 1i, 345i, 2015i, -10i). Note that all values must have a trailing i. If they do not they will be written as floats.
  • float - Numeric values that are not followed by a trailing i. (e.g. 1, 1.0, -3.14, 6.0+e5, 10).
  • boolean - A value indicating true or false. Valid boolean strings are (t, T, true, TRUE, f, F, false, and FALSE).
  • string - A text value. All string values must be surrounded in double-quotes ". If the string contains a double-quote or backslashes, it must be escaped with a backslash, e.g. \", \\.
# integer value
cpu value=1i

cpu value=1.1i # will result in a parse error

# float value
cpu_load value=1

cpu_load value=1.0

cpu_load value=1.2

# boolean value
error fatal=true

# string value
event msg="logged out"

# multiple values
cpu load=10,alert=true,reason="value above maximum threshold"

Timestamp

The timestamp section is optional but should be specified if possible. The value is an integer representing nanoseconds since the epoch. If the timestamp is not provided the point will inherit the server's local timestamp.

Some write APIs allow passing a lower precision. If the API supports a lower precision, the timestamp may also be an integer epoch in microseconds, milliseconds, seconds, minutes or hours.

Full Example

A full example is shown below.

cpu,host=server01,region=uswest value=1 1434055562000000000
cpu,host=server02,region=uswest value=3 1434055562000010000

In this example the first line shows a measurement of "cpu", there are two tags "host" and "region, the value is 1.0, and the timestamp is 1434055562000000000. Following this is a second line, also a point in the measurement "cpu" but belonging to a different "host".

cpu,host=server\ 01,region=uswest value=1,msg="all systems nominal"
cpu,host=server\ 01,region=us\,west value_int=1i

In these examples, the "host" is set to server 01. The field value associated with field key msg is double-quoted, as it is a string. The second example shows a region of us,west with the comma properly escaped. In the first example value is written as a floating point number. In the second, value_int is an integer.

Distributed Queries

# Packages

No description provided by the author

# Functions

DecodeStorePath extracts the database and retention policy names from a given shard or WAL path.
DedupeEntries returns slices with unique keys (the first 8 bytes).
IsNumeric returns whether a given aggregate can only be run on numeric fields.
IsRetryable returns true if this error is temporary and could be retried.
MarshalTags converts a tag set to bytes for use as a lookup key.
MeasurementFromSeriesKey returns the name of the measurement from a key that contains a measurement name.
MultiCursor returns a single cursor that combines the results of all cursors in order.
NewConfig returns the default configuration for tsdb.
NewDatabaseIndex returns a new initialized DatabaseIndex.
NewEngine returns an instance of an engine based on its format.
NewEngineOptions returns the default options.
NewFieldCodec returns a FieldCodec for the given Measurement.
No description provided by the author
NewFloatCursorIterator returns a new instance of FloatCursorIterator.
NewMeasurement allocates and initializes a new Measurement.
No description provided by the author
NewMeasurementIterator returns a new instance of MeasurementIterator.
NewPointBatcher returns a new PointBatcher.
NewSeries returns an initialized series struct.
NewSeriesIterator returns a new instance of SeriesIterator.
NewShard returns a new initialized Shard.
NewShardError returns a new ShardError.
NewStore returns a new store with the given path and a default configuration.
NewTagKeysIterator returns a new instance of TagKeysIterator.
NewTagValuesIterator returns a new instance of TagValuesIterator.
RegisteredEngines returns the slice of currently registered engines.
RegisterEngine registers a storage engine initializer by name.

# Constants

500MB.
25MB.
DefaultCacheSnapshotWriteColdDuration is the length of time at which the engine will snapshot the cache and write it to a new TSM file if the shard hasn't received writes or deletes.
DefaultCompactFullWriteColdDuration is the duration at which the engine will compact all TSM files in a shard if it hasn't received a write or delete.
DefaultEngine is the default engine for new shards.
DefaultMaxPointsPerBlock is the maximum number of points in an encoded block in a TSM file.
EOF represents a "not found" key returned by a Cursor.
TSM1Format is the format used by the tsm1 engine.

# Variables

ErrEngineClosed is returned when a caller attempts indirectly to access the shard's underlying engine.
ErrFieldNotFound is returned when a field cannot be found.
ErrFieldOverflow is returned when too many fields are created on a measurement.
ErrFieldTypeConflict is returned when a new field already exists with a different type.
ErrFieldUnmappedID is returned when the system is presented, during decode, with a field ID there is no mapping for.
ErrFormatNotFound is returned when no format can be determined from a path.
ErrShardNotFound gets returned when trying to get a non existing shard.
ErrStoreClosed gets returned when trying to use a closed Store.
ErrUnknownEngineFormat is returned when the engine format is unknown.

# Structs

Config holds the configuration for the tsbd package.
DatabaseIndex is the in memory index of a collection of measurements, time series, and their tags.
EngineOptions represents the options used to initialize the engine.
Field represents a series field.
FieldCodec provides encoding and decoding functionality for the fields of a given Measurement.
FieldCreate holds information for a field to create on a measurement.
FloatCursorIterator represents a wrapper for Cursor to produce an influxql.FloatIterator.
Measurement represents a collection of time series in a database.
MeasurementFields holds the fields of a measurement and their codec.
MeasurementIterator represents a string iterator that emits all measurement names in a shard.
PointBatcher accepts Points and will emit a batch of those points when either a) the batch reaches a certain size, or b) a certain time passes.
PointBatcherStats are the statistics each batcher tracks.
Series belong to a Measurement and represent unique time series in a database.
SeriesCreate holds information for a series to create.
Shard represents a self-contained time series database.
A ShardError implements the error interface, and contains extra context about the shard that generated the error.
Store manages shards and indexes for databases.
TagFilter represents a tag filter when looking up other tags or measurements.

# Interfaces

Cursor represents an iterator over a series.
Engine represents a swappable storage engine for the shard.

# Type aliases

ByteSlices wraps a list of byte-slices for sorting.
EngineFormat represents the format for an engine.
FilterExprs represents a map of series IDs to filter expressions.
Measurements represents a list of *Measurement.
NewEngineFunc creates a new engine.
SeriesIDs is a convenience type for sorting, checking equality, and doing union and intersection of collections of series ids.
Shards represents a sortable list of shards.