CouchDB-Golang Library v1.2
A Golang library for working with CouchDB 2.x
supported Golang version:

- Resource : a simple wrapper for HTTP requests and error handling
- Server : CouchDB server instance
- Database : CouchDB database instance
- ViewResults : a representation of the results produced by design document views
- ViewDefinition : a definition of view stored in a specific design document
- Document : a representation of document object in database
Inspired by CouchDB-Python
Documentation
package couchdb
import "github.com/leesper/couchdb"
Constants
const (
DefaultBaseURL = "http://localhost:5984"
)
Variables
var (
ErrBatchValue = errors.New("batch must be 1 or more")
ErrLimitValue = errors.New("limit must be 1 or more")
)
var (
ErrSetID = errors.New("id can only be set on new documents")
ErrNotStruct = errors.New("value not of struct type")
ErrNotDocumentEmbedded = errors.New("value not Document-embedded")
)
var (
ErrNotModified = errors.New("status 304 - not modified")
ErrBadRequest = errors.New("status 400 - bad request")
ErrUnauthorized = errors.New("status 401 - unauthorized")
ErrForbidden = errors.New("status 403 - forbidden")
ErrNotFound = errors.New("status 404 - not found")
ErrResourceNotAllowed = errors.New("status 405 - resource not allowed")
ErrNotAcceptable = errors.New("status 406 - not acceptable")
ErrConflict = errors.New("status 409 - conflict")
ErrPreconditionFailed = errors.New("status 412 - precondition failed")
ErrBadContentType = errors.New("status 415 - bad content type")
ErrRequestRangeNotSatisfiable = errors.New("status 416 - requested range not satisfiable")
ErrExpectationFailed = errors.New("status 417 - expectation failed")
ErrInternalServerError = errors.New("status 500 - internal server error")
)
func FromJSONCompatibleMap
func FromJSONCompatibleMap(obj interface{}, docMap map[string]interface{}) error
FromJSONCompatibleMap constructs a Document-embedded struct from a JSON-compatible map.
func GenerateUUID
func GenerateUUID() string
GenerateUUID returns a random 128-bit UUID
func Load
func Load(db *Database, docID string, obj interface{}) error
Load loads the document in specified database.
func Store
func Store(db *Database, obj interface{}) error
Store stores the document in specified database.
func SyncMany
func SyncMany(db *Database, viewDefns []*ViewDefinition, removeMissing bool, callback func(map[string]interface{})) ([]UpdateResult, error)
SyncMany ensures that the views stored in the database match the views defined by the corresponding view definitions. This function might update more than one design document. This is done using CouchDB's bulk update to ensure atomicity of the opeation. db: the corresponding database.
viewDefns: a sequence of *ViewDefinition instances.
removeMissing: whether to remove views found in a design document that are not found in the list of ViewDefinition instances, default false.
callback: a callback function invoked when a design document gets updated; it is called before the doc has actually been saved back to the database.
func ToJSONCompatibleMap
func ToJSONCompatibleMap(obj interface{}) (map[string]interface{}, error)
ToJSONCompatibleMap converts a Document-embedded struct into a JSON-compatible map, e.g. anything that cannot be jsonified will be ignored silently.
type Database
type Database struct {
}
Database represents a CouchDB database instance.
func NewDatabase
func NewDatabase(urlStr string) (*Database, error)
NewDatabase returns a CouchDB database instance.
func NewDatabaseWithResource
func NewDatabaseWithResource(res *Resource) (*Database, error)
NewDatabaseWithResource returns a CouchDB database instance with resource obj.
func (d *Database) Available
func (d *Database) Available() error
Available returns error if the database is not good to go.
func (d *Database) Changes
func (d *Database) Changes(options url.Values) (map[string]interface{}, error)
Changes returns a sorted list of changes feed made to documents in the database.
func (d *Database) Cleanup
func (d *Database) Cleanup() error
Cleanup removes all view index files no longer required by CouchDB.
func (d *Database) Commit
func (d *Database) Commit() error
Commit flushes any recent changes to the specified database to disk. If the server is configured to delay commits or previous requests use the special "X-Couch-Full-Commit: false" header to disable immediate commits, this method can be used to ensure that non-commited changes are commited to physical storage.
func (d *Database) Compact
func (d *Database) Compact() error
Compact compacts the database by compressing the disk database file.
func (d *Database) Contains
func (d *Database) Contains(docid string) error
Contains returns true if the database contains a document with the specified ID.
func (d *Database) Copy
func (d *Database) Copy(srcID, destID, destRev string) (string, error)
Copy copies an existing document to a new or existing document.
func (d *Database) Delete
func (d *Database) Delete(docid string) error
Delete deletes the document with the specified ID.
func (d *Database) DeleteAttachment
func (d *Database) DeleteAttachment(doc map[string]interface{}, name string) error
DeleteAttachment deletes the specified attachment.
func (d *Database) DeleteDoc
func (d *Database) DeleteDoc(doc map[string]interface{}) error
DeleteDoc deletes the specified document
func (d *Database) DeleteIndex
func (d *Database) DeleteIndex(ddoc, name string) error
DeleteIndex deletes index in database.
func (d *Database) DocIDs
func (d *Database) DocIDs() ([]string, error)
DocIDs returns the IDs of all documents in database.
func (d *Database) Get
func (d *Database) Get(docid string, options url.Values) (map[string]interface{}, error)
Get returns the document with the specified ID.
func (d *Database) GetAttachment
func (d *Database) GetAttachment(doc map[string]interface{}, name string) ([]byte, error)
GetAttachment returns the file attachment associated with the document. The raw data is returned as a []byte.
func (d *Database) GetAttachmentID
func (d *Database) GetAttachmentID(docid, name string) ([]byte, error)
GetAttachmentID returns the file attachment associated with the document ID. The raw data is returned as []byte.
func (d *Database) GetIndex
func (d *Database) GetIndex() (map[string]*json.RawMessage, error)
GetIndex gets all indexes created in database.
func (d *Database) GetRevsLimit
func (d *Database) GetRevsLimit() (int, error)
GetRevsLimit gets the current revs_limit(revision limit) setting.
func (d *Database) GetSecurity
func (d *Database) GetSecurity() (map[string]interface{}, error)
GetSecurity returns the current security object from the given database.
func (d *Database) Info
func (d *Database) Info() (map[string]interface{}, error)
Info returns the information about the database.
func (*Database) IterView
func (d *Database) IterView(name string, batch int, wrapper func(Row) Row, options map[string]interface{}) (<-chan Row, error)
IterView returns a channel fetching rows in batches which iterates a row at a time(pagination).
name: the name of the view, for user-defined views use the format "design_docid/viewname", that is, the document ID of the design document and the name of the view, separated by a /.
wrapper: an optional function for processing the result rows after retrieved.
options: optional query parameters.
func (d *Database) Len
func (d *Database) Len() (int, error)
Len returns the number of documents stored in it.
func (*Database) List
func (d *Database) List(name, view string, options map[string]interface{}) (http.Header, []byte, error)
List formats a view using a server-side 'list' function.
name: the name of the list function in the format "designdoc/listname"
view: the name of the view in the format "designdoc/viewname"
options: optional query parameters
func (d *Database) Name
func (d *Database) Name() (string, error)
Name returns the name of database.
func (d *Database) Purge
func (d *Database) Purge(docs []map[string]interface{}) (map[string]interface{}, error)
Purge performs complete removing of the given documents.
func (d *Database) PutAttachment
func (d *Database) PutAttachment(doc map[string]interface{}, content []byte, name, mimeType string) error
PutAttachment uploads the supplied []byte as an attachment to the specified document. doc: the document that the attachment belongs to. Must have _id and _rev inside. content: the data to be attached to doc. name: name of attachment. mimeType: MIME type of content.
func (d *Database) PutIndex
func (d *Database) PutIndex(indexFields []string, ddoc, name string) (string, string, error)
PutIndex creates a new index in database. indexFields: a JSON array of field names following the sort syntax. ddoc: optional, name of the design document in which the index will be created. By default each index will be created in its own design document. Indexes can be grouped into design documents for efficiency. However a change to one index in a design document will invalidate all other indexes in the same document. name: optional, name of the index. A name generated automatically if not provided.
func (d *Database) Query
func (d *Database) Query(fields []string, selector string, sorts []string, limit, skip, index interface{}) ([]map[string]interface{}, error)
Query returns documents using a conditional selector statement in Golang.
selector: A filter string declaring which documents to return, formatted as a Golang statement.
fields: Specifying which fields to be returned, if passing nil the entire is returned, no automatic inclusion of _id or other metadata fields.
sorts: How to order the documents returned, formatted as ["desc(fieldName1)", "desc(fieldName2)"] or ["fieldNameA", "fieldNameB"] of which "asc" is used by default, passing nil to disable ordering.
limit: Maximum number of results returned, passing nil to use default value(25).
skip: Skip the first 'n' results, where 'n' is the number specified, passing nil for no-skip.
index: Instruct a query to use a specific index, specified either as "<design_document>" or ["<design_document>", "<index_name>"], passing nil to use primary index(_all_docs) by default.
Inner functions for selector syntax
nor(condexprs...) matches if none of the conditions in condexprs match($nor).
For example: nor(year == 1990, year == 1989, year == 1997) returns all documents whose year field not in 1989, 1990 and 1997.
all(field, array) matches an array value if it contains all the elements of the argument array($all).
For example: all(genre, []string{"Comedy", "Short"} returns all documents whose genre field contains "Comedy" and "Short".
any(field, condexpr) matches an array field with at least one element meets the specified condition($elemMatch).
For example: any(genre, genre == "Short" || genre == "Horror") returns all documents whose genre field contains "Short" or "Horror" or both.
exists(field, boolean) checks whether the field exists or not, regardless of its value($exists).
For example: exists(director, false) returns all documents who does not have a director field.
typeof(field, type) checks the document field's type, valid types are "null", "boolean", "number", "string", "array", "object"($type).
For example: typeof(genre, "array") returns all documents whose genre field is of array type.
in(field, array) the field must exist in the array provided($in).
For example: in(director, []string{"Mike Portnoy", "Vitali Kanevsky"}) returns all documents whose director field is "Mike Portnoy" or "Vitali Kanevsky".
nin(field, array) the document field must not exist in the array provided($nin).
For example: nin(year, []int{1990, 1992, 1998}) returns all documents whose year field is not in 1990, 1992 or 1998.
size(field, int) matches the length of an array field in a document($size).
For example: size(genre, 2) returns all documents whose genre field is of length 2.
mod(field, divisor, remainder) matches documents where field % divisor == remainder($mod).
For example: mod(year, 2, 1) returns all documents whose year field is an odd number.
regex(field, regexstr) a regular expression pattern to match against the document field.
For example: regex(title, "^A") returns all documents whose title is begin with an "A".
##Inner functions for sort syntax
asc(field) sorts the field in ascending order, this is the default option while desc(field) sorts the field in descending order.
func (d *Database) QueryJSON
func (d *Database) QueryJSON(query string) ([]map[string]interface{}, error)
QueryJSON returns documents using a declarative JSON querying syntax.
func (d *Database) Revisions
func (d *Database) Revisions(docid string, options url.Values) ([]map[string]interface{}, error)
Revisions returns all available revisions of the given document in reverse order, e.g. latest first.
func (d *Database) Save
func (d *Database) Save(doc map[string]interface{}, options url.Values) (string, string, error)
Save creates a new document or update an existing document. If doc has no _id the server will generate a random UUID and a new document will be created. Otherwise the doc's _id will be used to identify the document to create or update. Trying to update an existing document with an incorrect _rev will cause failure. NOTE It is recommended to avoid saving doc without _id and instead generate document ID on client side. To avoid such problems you can generate a UUID on the client side. GenerateUUID provides a simple, platform-independent implementation. You can also use other third-party packages instead. doc: the document to create or update.
func (d *Database) Set
func (d *Database) Set(docid string, doc map[string]interface{}) error
Set creates or updates a document with the specified ID.
func (d *Database) SetRevsLimit
func (d *Database) SetRevsLimit(limit int) error
SetRevsLimit sets the maximum number of document revisions that will be tracked by CouchDB.
func (d *Database) SetSecurity
func (d *Database) SetSecurity(securityDoc map[string]interface{}) error
SetSecurity sets the security object for the given database.
func (*Database) Show
func (d *Database) Show(name, docID string, params url.Values) (http.Header, []byte, error)
Show calls a server-side 'show' function.
name: the name of the show function in the format "designdoc/showname"
docID: optional document ID to pass to the show function
params: optional query parameters
func (d *Database) String
func (d *Database) String() string
func (d *Database) Update
func (d *Database) Update(docs []map[string]interface{}, options map[string]interface{}) ([]UpdateResult, error)
Update performs a bulk update or creation of the given documents in a single HTTP request. It returns a 3-tuple (id, rev, error)
func (*Database) UpdateDoc
func (d *Database) UpdateDoc(name, docID string, params url.Values) (http.Header, []byte, error)
UpdateDoc calls server-side update handler.
name: the name of the update handler function in the format "designdoc/updatename".
docID: optional document ID to pass to the show function
params: optional query parameters
func (*Database) View
func (d *Database) View(name string, wrapper func(Row) Row, options map[string]interface{}) (*ViewResults, error)
View executes a predefined design document view and returns the results.
name: the name of the view, for user-defined views use the format "design_docid/viewname", that is, the document ID of the design document and the name of the view, separated by a /.
wrapper: an optional function for processing the result rows after retrieved.
options: optional query parameters.
type Document
type Document struct {
ID string `json:"_id,omitempty"`
Rev string `json:"_rev,omitempty"`
}
Document represents a document object in database.
func DocumentWithID
func DocumentWithID(id string) Document
DocumentWithID returns a new Document with ID.
func (*Document) GetID
func (d *Document) GetID() string
GetID returns the document ID.
func (*Document) GetRev
func (d *Document) GetRev() string
GetRev returns the document revision.
func (*Document) SetID
func (d *Document) SetID(id string) error
SetID sets ID for new document or return error.
func (*Document) SetRev
func (d *Document) SetRev(rev string)
SetRev sets revision for document.
type Resource
type Resource struct {
}
Resource handles all requests to CouchDB.
func NewResource
func NewResource(urlStr string, header http.Header) (*Resource, error)
NewResource returns a newly-created Resource instance.
func (r *Resource) Delete
func (r *Resource) Delete(path string, header http.Header, params url.Values) (http.Header, []byte, error)
Delete is a wrapper around http.Delete.
func (r *Resource) DeleteJSON
func (r *Resource) DeleteJSON(path string, header http.Header, params url.Values) (http.Header, []byte, error)
DeleteJSON issues a DELETE to the specified URL, with data returned as json.
func (r *Resource) Get
func (r *Resource) Get(path string, header http.Header, params url.Values) (http.Header, []byte, error)
Get is a wrapper around http.Get.
func (r *Resource) GetJSON
func (r *Resource) GetJSON(path string, header http.Header, params url.Values) (http.Header, []byte, error)
GetJSON issues a GET to the specified URL, with data returned as json.
func (r *Resource) Head
func (r *Resource) Head(path string, header http.Header, params url.Values) (http.Header, []byte, error)
Head is a wrapper around http.Head.
func (r *Resource) NewResourceWithURL
func (r *Resource) NewResourceWithURL(resStr string) (*Resource, error)
NewResourceWithURL returns newly created *Resource combined with resource string.
func (r *Resource) Post
func (r *Resource) Post(path string, header http.Header, body []byte, params url.Values) (http.Header, []byte, error)
Post is a wrapper around http.Post.
func (r *Resource) PostJSON
func (r *Resource) PostJSON(path string, header http.Header, body map[string]interface{}, params url.Values) (http.Header, []byte, error)
PostJSON issues a POST to the specified URL, with data returned as json.
func (r *Resource) Put
func (r *Resource) Put(path string, header http.Header, body []byte, params url.Values) (http.Header, []byte, error)
Put is a wrapper around http.Put.
func (r *Resource) PutJSON
func (r *Resource) PutJSON(path string, header http.Header, body map[string]interface{}, params url.Values) (http.Header, []byte, error)
PutJSON issues a PUT to the specified URL, with data returned as json.
type Row
type Row struct {
ID string
Key interface{}
Val interface{}
Doc interface{}
Err error
}
Row represents a row returned by database views.
func (Row) String
func (r Row) String() string
String returns a string representation for Row
type Server
type Server struct {
}
Server represents a CouchDB server instance.
func NewServer
func NewServer(urlStr string) (*Server, error)
NewServer creates a CouchDB server instance in address urlStr.
func NewServerNoFullCommit
func NewServerNoFullCommit(urlStr string) (*Server, error)
NewServerNoFullCommit creates a CouchDB server instance in address urlStr with X-Couch-Full-Commit disabled.
func (s *Server) ActiveTasks
func (s *Server) ActiveTasks() ([]interface{}, error)
ActiveTasks lists of running tasks.
func (s *Server) AddUser
func (s *Server) AddUser(name, password string, roles []string) (string, string, error)
AddUser adds regular user in authentication database. Returns id and rev of the registered user.
func (s *Server) Config
func (s *Server) Config(node string) (map[string]map[string]string, error)
Config returns the entire CouchDB server configuration as JSON structure.
func (s *Server) Contains
func (s *Server) Contains(name string) bool
Contains returns true if a db with given name exsited.
func (s *Server) Create
func (s *Server) Create(name string) (*Database, error)
Create returns a database instance with the given name, returns true if created, if database already existed, returns false, *Database will be nil if failed.
func (s *Server) DBs
func (s *Server) DBs() ([]string, error)
DBs returns a list of all the databases in the CouchDB server instance.
func (s *Server) Delete
func (s *Server) Delete(name string) error
Delete deletes a database with the given name. Return false if failed.
func (s *Server) Get
func (s *Server) Get(name string) (*Database, error)
Get gets a database instance with the given name. Return nil if failed.
func (s *Server) Len
func (s *Server) Len() (int, error)
Len returns the number of dbs in CouchDB server instance.
func (s *Server) Login
func (s *Server) Login(name, password string) (string, error)
Login regular user in CouchDB, returns authentication token.
func (s *Server) Logout
func (s *Server) Logout(token string) error
Logout regular user in CouchDB.
func (s *Server) Membership
func (s *Server) Membership() ([]string, []string, error)
Membership displays the nodes that are part of the cluster as clusterNodes. The field allNodes displays all nodes this node knows about, including the ones that are part of cluster.
func (s *Server) RemoveUser
func (s *Server) RemoveUser(name string) error
RemoveUser removes regular user in authentication database.
func (s *Server) Replicate
func (s *Server) Replicate(source, target string, options map[string]interface{}) (map[string]interface{}, error)
Replicate requests, configure or stop a replication operation.
func (s *Server) Stats
func (s *Server) Stats(node, entry string) (map[string]interface{}, error)
Stats returns a JSON object containing the statistics for the running server.
func (s *Server) String
func (s *Server) String() string
func (s *Server) UUIDs
func (s *Server) UUIDs(count int) ([]string, error)
UUIDs requests one or more Universally Unique Identifiers from the CouchDB instance. The response is a JSON object providing a list of UUIDs. count - Number of UUIDs to return. Default is 1.
func (s *Server) VerifyToken
func (s *Server) VerifyToken(token string) error
VerifyToken returns error if user's token is invalid.
func (s *Server) Version
func (s *Server) Version() (string, error)
Version returns the version info about CouchDB instance.
type UpdateResult
type UpdateResult struct {
ID, Rev string
Err error
}
UpdateResult represents result of an update.
type ViewDefinition
type ViewDefinition struct {
}
ViewDefinition is a definition of view stored in a specific design document.
func NewViewDefinition
func NewViewDefinition(design, name, mapFun, reduceFun, language string, wrapper func(Row) Row, options map[string]interface{}) (*ViewDefinition, error)
NewViewDefinition returns a newly-created *ViewDefinition. design: the name of the design document.
name: the name of the view.
mapFun: the map function code.
reduceFun: the reduce function code(optional).
language: the name of the programming language used, default is javascript.
wrapper: an optional function for processing the result rows after retrieved.
options: view specific options.
func (*ViewDefinition) GetDoc
func (vd *ViewDefinition) GetDoc(db *Database) (map[string]interface{}, error)
GetDoc retrieves the design document corresponding to this view definition from the given database.
func (*ViewDefinition) Sync
func (vd *ViewDefinition) Sync(db *Database) ([]UpdateResult, error)
Sync ensures that the view stored in the database matches the view defined by this instance.
func (*ViewDefinition) View
func (vd *ViewDefinition) View(db *Database, options map[string]interface{}) (*ViewResults, error)
View executes the view definition in the given database.
type ViewField
type ViewField func() (*ViewDefinition, error)
ViewField represents a view definition value bound to Document.
func NewViewField
func NewViewField(design, name, mapFun, reduceFun, language string, wrapper func(Row) Row, options map[string]interface{}) ViewField
NewViewField returns a ViewField function. design: the name of the design document.
name: the name of the view.
mapFun: the map function code.
reduceFun: the reduce function code(optional).
language: the name of the programming language used, default is javascript.
wrapper: an optional function for processing the result rows after retrieved.
options: view specific options.
type ViewResults
type ViewResults struct {
}
ViewResults represents the results produced by design document views.
func (*ViewResults) Offset
func (vr *ViewResults) Offset() (int, error)
Offset returns offset of ViewResults
func (*ViewResults) Rows
func (vr *ViewResults) Rows() ([]Row, error)
Rows returns a slice of rows mapped (and reduced) by the view.
func (*ViewResults) TotalRows
func (vr *ViewResults) TotalRows() (int, error)
TotalRows returns total rows of ViewResults
func (*ViewResults) UpdateSeq
func (vr *ViewResults) UpdateSeq() (int, error)
UpdateSeq returns update sequence of ViewResults