Go client for Pilosa high performance distributed bitmap index.
-
Next:
- Dropped support for Go 1.7
- Added support for creating range encoded frames.
- Added
SetFieldValue
,Average
,Sum
andXor
calls. - Added support for excluding bits or attributes from bitmap calls. In order to exclude bits, pass
ExcludeBits: true
in yourQueryOptions
. In order to exclude attributes, passExcludeAttrs: true
.
-
v0.5.0 (2017-08-03):
- Supports imports and exports.
- Introduced schemas. No need to re-define already existing indexes and frames.
NewClientFromAddresses
convenience function added. Create a client for a cluster directly from a slice of strings.- Failover for connection errors.
- make commands are supported on Windows.
- Deprecation
NewIndex
. Useschema.Index
instead. - Deprecation
CreateIndex
,CreateFrame
,EnsureIndex
,EnsureFrame
. Use schemas andclient.SyncSchema
instead.
-
v0.4.0 (2017-06-09):
- Supports Pilosa Server v0.4.0.
- Updated the accepted values for index, frame names and labels to match with the Pilosa server.
Union
query now accepts zero or more variadic arguments.Intersect
andDifference
queries now accept one or more variadic arguments.- Added
inverse TopN
andinverse Range
calls. - Inverse enabled status of frames is not checked on the client side.
-
v0.3.1 (2017-05-01):
- Initial version
- Supports Pilosa Server v0.3.1
- Go 1.8 and higher
Download the library in your GOPATH
using:
go get github.com/pilosa/go-pilosa
After that, you can import that in your code using:
import pilosa "pilosa/go-pilosa"
Assuming Pilosa server is running at localhost:10101
(the default):
var err error
// Create the default client
client := pilosa.DefaultClient()
// Retrieve the schema
schema, err := client.Schema()
// Create an Index object
myindex, err := schema.Index("myindex", nil)
// Create a Frame object
myframe, err := myindex.Frame("myframe", nil)
// make sure the index and frame exists on the server
err = client.SyncSchema(schema)
// Send a SetBit query. PilosaException is thrown if execution of the query fails.
err = client.Query(myframe.SetBit(5, 42), nil)
// Send a Bitmap query. PilosaException is thrown if execution of the query fails.
response, err = client.Query(myframe.Bitmap(5), nil)
// Get the result
result := response.Result()
// Act on the result
if result != nil {
bits := result.Bitmap.Bits
fmt.Println("Got bits: %v", bits)
}
// You can batch queries to improve throughput
response, err = client.Query(
myindex.BatchQuery(
myframe.Bitmap(5),
myframe.Bitmap(10),
), nil
)
for _, result := range reponse.Results() {
// Act on the result
}
Index and frames are the main data models of Pilosa. You can check the Pilosa documentation for more detail about the data model.
schema.Index
function is used to create an index object. Note that this does not create an index on the server; the index object simply defines the schema.
schema := NewSchema()
repository, err := NewIndex("repository", nil)
Indexes support changing the column label and time quantum. In order to apply these custom options, pass an IndexOptions
struct as the second argument to NewIndex
:
options := &pilosa.IndexOptions{
ColumnLabel: "repo_id",
TimeQuantum: TimeQuantumYearMonth,
}
repository, err := schema.Index("repository", options);
Frames definitions are created with a call to Frame
function of an index:
stargazer, err := repository.Frame("stargazer", nil)
Similar to index objects, you can pass custom options to frames:
stargazerOptions, err := &pilosa.FrameOptions{
RowLabel: "stargazer_id",
TimeQuantum: TimeQuantumYearMonthDay,
}
stargazer, err := repository.Frame("stargazer", stargazerOptions);
Once you have indexes and frame structs created, you can create queries for them. Some of the queries work on the columns; corresponding methods are attached to the index. Other queries work on rows with related methods attached to frames.
For instance, Bitmap
queries work on rows; use a frame object to create those queries:
bitmapQuery := stargazer.Bitmap(1, 100) // corresponds to PQL: Bitmap(frame='stargazer', stargazer_id=1)
Union
queries work on columns; use the index object to create them:
query := repository.Union(bitmapQuery1, bitmapQuery2)
In order to increase througput, you may want to batch queries sent to the Pilosa server. The index.BatchQuery
function is used for that purpose:
query := repository.BatchQuery(
stargazer.Bitmap(1, 100),
repository.Union(stargazer.Bitmap(100, 200), stargazer.Bitmap(5, 100))
)
The recommended way of creating query structs is, using dedicated methods attached to index and frame objects. But sometimes it would be desirable to send raw queries to Pilosa. You can use index.RawQuery
method for that. Note that query string is not validated before sending to the server:
query := repository.RawQuery("Bitmap(frame='stargazer', stargazer_id=5)")
Please check Pilosa documentation for PQL details. Here is a list of methods corresponding to PQL calls:
Index:
Union(bitmaps *PQLBitmapQuery...) *PQLBitmapQuery
Intersect(bitmaps *PQLBitmapQuery...) *PQLBitmapQuery
Difference(bitmaps *PQLBitmapQuery...) *PQLBitmapQuery
Xor(bitmaps ...*PQLBitmapQuery) *PQLBitmapQuery
Count(bitmap *PQLBitmapQuery) *PQLBaseQuery
SetColumnAttrs(columnID uint64, attrs map[string]interface{}) *PQLBaseQuery
Frame:
Bitmap(rowID uint64) *PQLBitmapQuery
InverseBitmap(columnID uint64) *PQLBitmapQuery
SetBit(rowID uint64, columnID uint64) *PQLBaseQuery
SetBitTimestamp(rowID uint64, columnID uint64, timestamp time.Time) *PQLBaseQuery
ClearBit(rowID uint64, columnID uint64) *PQLBaseQuery
TopN(n uint64) *PQLBitmapQuery
BitmapTopN(n uint64, bitmap *PQLBitmapQuery) *PQLBitmapQuery
FilterFieldTopN(n uint64, bitmap *PQLBitmapQuery, field string, values ...interface{}) *PQLBitmapQuery
InverseTopN(n uint64) *PQLBitmapQuery
InverseBitmapTopN(n uint64, bitmap *PQLBitmapQuery) *PQLBitmapQuery
InverseFilterFieldTopN(n uint64, bitmap *PQLBitmapQuery, field string, values ...interface{}) *PQLBitmapQuery
Range(rowID uint64, start time.Time, end time.Time) *PQLBitmapQuery
InverseRange(columnID uint64, start time.Time, end time.Time) *PQLBitmapQuery
SetRowAttrs(rowID uint64, attrs map[string]interface{}) *PQLBaseQuery
SumReduce(bitmap *PQLBitmapQuery, field string) *PQLBaseQuery
SetIntFieldValue(columnID uint64, field string, value int) *PQLBaseQuery
A Pilosa URI has the ${SCHEME}://${HOST}:${PORT}
format:
- Scheme: Protocol of the URI. Default:
http
. - Host: Hostname or ipv4/ipv6 IP address. Default: localhost.
- Port: Port number. Default:
10101
.
All parts of the URI are optional, but at least one of them must be specified. The following are equivalent:
http://localhost:10101
http://localhost
http://:10101
localhost:10101
localhost
:10101
A Pilosa URI is represented by the pilosa.URI
struct. Below are a few ways to create URI
objects:
// create the default URI: http://localhost:10101
uri1 := pilosa.DefaultURI()
// create a URI from string address
uri2, err := pilosa.NewURIFromAddress("index1.pilosa.com:20202");
// create a URI with the given host and port
uri3, err := pilosa.NewURIFromHostPort("index1.pilosa.com", 20202);
In order to interact with a Pilosa server, an instance of pilosa.Client
should be created. The client is thread-safe and uses a pool of connections to the server, so we recommend creating a single instance of the client and sharing it when necessary.
If the Pilosa server is running at the default address (http://localhost:10101
) you can create the client with default options using:
client := pilosa.DefaultClient()
To use a custom server address, use the NewClientWithURI
function:
uri, err := pilosa.NewURIFromAddress("http://index1.pilosa.com:15000")
if err != nil {
// Act on the error
}
client := pilosa.NewClientWithURI(uri)
If you are running a cluster of Pilosa servers, you can create a Cluster
struct that keeps addresses of those servers:
uri1, err := pilosa.NewURIFromAddress(":10101")
uri2, err := pilosa.NewURIFromAddress(":10110")
uri3, err := pilosa.NewURIFromAddress(":10111")
cluster := pilosa.NewClusterWithHost(uri1, uri2, uri3)
// Create a client with the cluster
client := pilosa.NewClientWithCluster(cluster, nil)
It is possible to customize the behaviour of the underlying HTTP client by passing a ClientOptions
struct to the NewClientWithCluster
function:
options = &pilosa.ClientOptions{
ConnectTimeout: 1000, // if can't connect in a second, close the connection
setSocketTimeout: 10000, // if no response received in 10 seconds, close the connection
PoolSizePerRoute: 3, // number of connections in the pool per host
TotalPoolSize: 10, // number of total connections in the pool
}
client := pilosa.NewClientWithCluster(cluster, options)
Once you create a client, you can create indexes, frames or start sending queries.
Here is how you would create a index and frame:
// materialize repository index definition and stargazer frame definition initialized before
err := client.SyncSchema(schema)
You can send queries to a Pilosa server using the Query
function of the Client
struct:
response, err := client.Query(frame.Bitmap(5), nil);
The second argument of Query
function is of type QueryOptions
:
options = &pilosa.QueryOptions{
Columns: true, // return column data in the response
}
response := client.Query(frame.Bitmap(5), options)
When a query is sent to a Pilosa server, the server either fulfills the query or sends an error message. In the case of an error, a pilosa.Error
struct is returned, otherwise a QueryResponse
struct is returned.
A QueryResponse
struct may contain zero or more results of QueryResult
type. You can access all results using the Results
function of QueryResponse
(which returns a list of QueryResult
objects), or you can use the Result
method (which returns either the first result or nil
if there are no results):
response, err := client.Query(frame.Bitmap(5). nil)
if err != nil {
// Act on the error
}
// check that there's a result and act on it
result := response.Result()
if result != nil {
// Act on the result
}
// iterate over all results
for result := range response.Results() {
// Act on the result
}
Similarly, a QueryResponse
struct may include a number of columns (column objects) if Columns
query option was set to true
:
var column *pilosa.ColumnItem
// check that there's a column and act on it
column = response.Column()
if (column != null) {
// Act on the column
}
// iterate over all columns
for column = range response.Columns() {
// Act on the column
}
QueryResult
objects contain:
Bitmap
field to retrieve a bitmap result,CountItems
fied to retrieve column count per row ID entries returned fromTopN
queries,Count
field to retrieve the number of rows per the given row ID returned fromCount
queries.
bitmap := result.Bitmap
bits := bitmap.Bits
attributes := bitmap.Attributes
countItems := result.CountItems
count := result.Count
If you have large amounts of data, it is more efficient to import it into Pilosa instead of using multiple SetBit queries. This library supports importing bits into an existing frame.
Before starting the import, create an instance of a struct which implements BitIterator
and pass it to the client.ImportFrame
function. This library ships with the CSVBitIterator
struct which supports importing bits in the CSV (comma separated values) format:
ROW_ID,COLUMN_ID
Optionally, a timestamp can be added. Note that Pilosa is not time zone aware:
ROW_ID,COLUMN_ID,TIMESTAMP
Note that each line corresponds to a single bit and ends with a new line (\n
or \r\n
).
Here's some sample code:
text := `10,7
10,5
2,3
7,1`
iterator := NewCSVBitIterator(strings.NewReader(text))
After creating the iterator you can pass it to client.ImportFrame
together with the frame and batch size. The following sample sends batches with size 10000 bits:
err = client.ImportFrame(frame, iterator, 10000)
if err != nil {
panic(err)
}
You can define a custom BitIterator
by including a function with the signature NextBit() (Bit, error)
in your struct.
type StaticBitIterator struct {
NextBit() (Bit, error)
bits []Bit
index int
}
func NewStaticBitIterator() *StaticBitIterator {
return &StaticBitIterator{
bits: []Bit{
Bit{RowID: 1, ColumnID: 1, Timestamp: 683793200},
Bit{RowID: 5, ColumnID: 20, Timestamp: 683793300},
Bit{RowID: 3, ColumnID: 41, Timestamp: 683793385},
}
}
}
func (it *StatiBitIterator) NextBit(Bit, error) {
if it.index < len(it.bits) {
return Bit{}, io.EOF
}
return it.bits[it.index++], nil
}
You can export a view of a frame from Pilosa using client.ExportFrame
function which returns a BitIterator
. Use the NextBit
function of this iterator to receive all bits for the specified frame. When there are no more bits, io.EOF
is returned.
The PilosaClient
struct has the Views
function which returns all of the views for a particular frame. You can use this function to retrieve view names:
views, err := client.Views(frame)
Here's sample code which retrieves bits of the standard
view:
bits := []Bit{}
iterator, err := client.ExportFrame(frame, "standard")
if err != nil {
t.Fatal(err)
}
for {
bit, err := iterator.NextBit()
if err == io.EOF {
break
}
if err != nil {
t.Fatal(err)
}
bits = append(bits, bit)
}
Please check our Contributor's Guidelines.
- Fork this repo and add it as upstream:
git remote add upstream git@github.com:pilosa/go-pilosa.git
. - Make sure all tests pass (use
make test-all
) and be sure that the tests cover all statements in your code (we aim for 100% test coverage). - Commit your code to a feature branch and send a pull request to the
master
branch of our repo.
You can run unit tests with:
make test
And both unit and integration tests with:
make test-all
Check the test coverage:
make cover
Protobuf classes are already checked in to source control, so this step is only needed when the upstream public.proto
changes.
Before running the following step, make sure you have the Protobuf compiler and Go protobuf support is installed:
make generate
Copyright 2017 Pilosa Corp.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
3. Neither the name of the copyright holder nor the names of its
contributors may be used to endorse or promote products derived
from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
DAMAGE.