A Golang library for CouchDB 2.x, inspired by CouchDB-Python.
- 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
- tools/replicate : a command-line tool for replicating
func (d *Database) Query(fields []string, selector string, sorts []string, limit, skip, index interface{}) ([]map[string]interface{}, error)You can query documents using a conditional selector statement in Golang. It will converts to the corresponding JSON query string.
- 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.
For example:
docsQuery, err := movieDB.Query(nil, `year == 1989 && (director == "Ademir Kenovic" || director == "Dezs Garas")`, nil, nil, nil, nil)equals to:
docsRaw, err := movieDB.QueryJSON(`
{
"selector": {
"year": 1989,
"$or": [
{ "director": "Ademir Kenovic" },
{ "director": "Dezs Garas" }
]
}
}`)-
nor(condexprs...) matches if none of the conditions in condexprs match($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".
asc(field) sorts the field in ascending order, this is the default option while desc(field) sorts the field in descending order.
- Golang 1.7.x and above
go get -u -v github.com/leesper/couchdb-golang
Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change. Please make sure to update unit tests as appropriate.